Based on our collective experiences with gap management around immediate dental implants, we have proposed a classification of gap type based on the location in relation to implant periphery. Seven types are proposed, and all but one type should heal without gap grafting provided that flap-less surgery and atraumatic extraction have been achieved. The exception is our Type II gap where the implant has been placed too far buccally leaving a gap only on the lingual/palatal. In this case, the lingual/palatal gap need not be grafted, but the buccal aspect of the implant should best to augmented to avoid the complications.

Tooth nonvitality is one of the frequently seen consequences of dental trauma that causes the arrest of root development. Amniotic membrane has received a lot of attention for its use in transplantation and regeneration procedures. This article reports a unique and novel case of successful regenerative endodontic procedure done using amniotic membrane in a traumatized immature right maxillary central incisor of an 8-year-old girl. The clinical and radiographic evaluation done during the recall visits at 1, 3, 6, 9 and 12 months showed a progressive root growth with apical closure.

Background: Association of cuspid impaction with adjacent lateral incisor anomalies is under controversy. The aim of this study was to investigate the correlation between maxillary cuspid impaction with dental anomalies. Material and Methods: In this in vitro experimental study, the material consisted of pretreatment dental records of 102 patients with at least one palatally or buccally displaced impacted permanent cuspid (palatal and buccal impaction groups). They were matched with a comparison control group of 102 patients having normally erupted maxillary cuspids. Available space, mesiodistal dimensions of teeth, and morphologic parameters of lateral incisors were measured using the digital caliper. Comparison of mean values of lateral incisors anomalies and severity of crowding between different groups were performed using the one-way ANOVA test, and the analysis of associations between position of the impaction and anomaly of the lateral incisors and severity of crowding was performed using the Chi-square test. P < 0.05 was considered statistically significant. Results: There was no statistically significant difference in the arch length–tooth size discrepancy between the cuspid impaction groups and control group. The impaction group (buccal or palatal) presented statistically significant differences in terms of anomalies of maxillary lateral incisor compared to the control group. Peg-shaped lateral incisor was related to buccal cuspid impaction and microdontia had relationship with palatal cuspid impaction. Conclusion: There is the relationship between cuspid impaction and adjacent lateral incisor abnormality, but no difference was observed between buccal and palatal cuspid impactions. Crowding revealed no relationship with cuspid impaction (buccal or palatal) in this study.

Background: Although dental care attendance during pregnancy has been recommended by guidelines and institutions, the demand for dental services is still low among pregnant women. The aim of this study was to examine the prevalence of not receipt dental care and also determinants of that during pregnancy. Materials and Methods: This population-based study was conducted on 4071 mothers in 10 provinces of Iran, during 2014–2015. We calculated the prevalence of not receipt of dental care, and reasons for nonreceipt of care. We used logistic regression to estimate odds of nonreceipt of care by demographics variables. In the analyses, the level of statistical significance was set at P < 0.05. Results: Overall, 54.70% of women had no dental visit during pregnancy. In mothers who had a history of stillbirth, neonatal death and live birth, the prevalence of not receipt dental care during pregnancy were 54.56%, 48.92%, and 58.76%, respectively. The logistic regression analyses showed that parity second-to-fourth birth than first birth (odds ratio [OR] 1.37 confidence interval [CI] 95% 1.17–1.59, residence in rural (OR 1.68 CI 95% 1.45–1.95), and not intended pregnancy (OR 1.32 CI 95% 1.03–1.68) associated with not received dental care during pregnancy. Conclusion: Most pregnant women in this study received insufficient dental care. The need for dental care during pregnancy must be promoted widely among women of reproductive age, and family barriers to dental care should be addressed.

Background: Despite the many advantages of simplified adhesive systems, there are concerns about the durability of the adhesive layer over time. The aim was to investigate the effects of various aging methods and double application of an adhesive layer on the bond strength of the universal adhesive system using etch-and-rinse (ER) and self-etch (SE) strategies. Materials and Methods: In this in vitro study, the occlusal enamel of 120 extracted, intact human third molars was removed to expose the dentin. Then, the samples were randomly divided into four groups of thirty according to All-Bond Universal (ABU) adhesive application strategy (ER and SE) and the number of adhesive layers (1 or 2). Then, each group was subdivided into three subgroups of ten according to aging method (control, thermal cycling, and 10% sodium hypochlorite [NaOCl]). The shear bond strength was measured at the strain rate of 0.5 mm/min. Data were analyzed using three-way ANOVA and Tukey's post hoc tests (P < 0.05). Results: The effect of adhesive application strategy (P < 0.001) and aging method (P < 0.001) on the bond strength was statistically significant, but the effect of the double application was not statistically significant (P > 0.05). In addition, the interactive effect of adhesive application strategy–aging method was significant (P = 0.005). Conclusion: Using ABU with ER strategy leads to higher dentin bond strength compared to the SE method in the control and thermal cycling groups. However, no significant differences were observed between ER and SE strategies after aging with the NaOCl. Furthermore, the double application might not have any effect on the bond strength and durability.

Background: Soft skills are the key indicators of success and quality of performance in various professions, including the dental profession. The skills are the main tools for enhancing the quality of technical work in Dentistry. Hence, the aim of this study was to identify and prioritize the soft skills in dental profession. Materials and Methods: The study employed a mixed methods research. In the qualitative phase, the dental skills were identified using a semi-structured interview with faculty members and dental students. In the quantitative phase, the soft skills were prioritized with Analytical Hierarchical Process (AHP). The data analysis was using Expert Choice software. Results: The results showed that the dental profession to improve the quality of performance needs to 29 soft skills in six categories. In professional ethics, work ethics (with weight of 0.212) and responsibility (0.188); in artistic skills, handicrafts (0.616); in cognitive skills, decision-making ability (0.290) and spatial thinking (0.249); in communication skills, verbal/nonverbal communication and listening (0.266), and patience (0.240); in individual characteristics, stress management (0.381) and self-esteem (0.260); and finally, in management skills, time management (0.481) are among the most important soft skills in dental profession. Conclusion: Identify and prioritize the soft skills can help to improve the quality of performance the dental profession. Therefore, it is recommended to integrate these skills into the dentistry curriculum. Moreover, by increasing the number of studies the essential backgrounds for developing soft skills in dentistry education will be provided.

The use of computer-aided design/computer-aided manufacturing technology simplifies the laboratory and clinical steps for the fabrication of implant prostheses. It also reduces additional costs for the prosthetic components and technical procedures. This article describes a modified impression technique using an impression metal jig to enhance the accuracy of final impression and also to eliminate the need for the try-in of resin pattern of the milled bar.

Background: This study aimed to compare the effect of four temporary luting agents on preventing the coronal microleakage of teeth restored with custom cast post and core. Materials and Methods: In this in vitro original study, after removing 9 mm of gutta percha from root canals of 32 single-canaled premolars, the acrylic resin patterns of the post and core were fabricated. Patterns were cast with Ni-Cr metal alloy and then cemented with glass ionomer. Using self-curing acrylic resin, provisional restorations were made. Then, teeth were randomly allocated to four groups for each temporary cement including zinc oxide eugenol (Temp Bond), zinc oxide noneugenol (Temp Bond NE), noneugenol resin-based temporary luting agent (Temp Bond Clear), and noneugenol urethane methacrylate polymer-based temporary luting agent (Dento temp). Teeth were subjected to thermocycling, immersed in silver nitrate for 6 h and then sectioned. The amount of dye penetration in the margin of provisional crown and into the coronal part of the root canals was measured using a stereomicroscope. Data were analyzed using the Kruskal–Wallis and Dunn tests with significance level of 0.05. Results: All the luting agents showed some degree of microleakage (Group 1 showed the most microleakage). According to the pair comparison between the groups, Group 1 revealed a significant difference with others (P < 0.05). Furthermore, Group 2 showed more microleakage as compared to Group 4 (P = 0.037). Conclusion: Temp Bond showed the highest microleakage as compared to other luting agents. Furthermore, Temp Bond NE revealed a weaker sealability as compared to Dento temp.

Background: The aim of this study was to compare the effect of chlorhexidine- and Persica-containing mouthrinses on the surface characterization of orthodontic appliance and friction between the orthodontic stainless steel wires and brackets. Materials and Methods: In this randomized controlled trial, 75 orthodontic patients (aged 13–30) were allocated (n = 25) into two experimental groups (prescribed by Persica- or chlorhexidine-containing mouthrinse) and one control group (no prescription). The ovoid stainless steel archwires were placed, and the maxillary first premolar stainless steel edgewise brackets were ligated to wires by elastomeric rings. The patients were recalled after 2 weeks, and then, the archwires were removed and replaced. The surface analysis of archwires and brackets was evaluated using scanning electron microscopy and atomic force microscopy. The frictional forces between the archwires and brackets were measured using a universal testing machine. The data for surface roughness were analyzed by the nonparametric Kruskal–Wallis and Mann–Whitney tests. The frictional forces data were analyzed using a two-way analysis of variance and Tukey's post hoc test using SPSS software. The level of significance was P < 0.05. Results: The retrieved brackets showed minor changes in their surface topography. The surface roughness of archwires after the intervention was significantly greater for the chlorhexidine than that of Persica (P < 0.05). The friction force between the archwires and brackets was also significantly higher for the chlorhexidine than that of Persica (P < 0.05). Conclusion: The Persica-containing mouthrinse from the biomechanical and biochemical standpoints may be a better option for oral hygiene in orthodontic patients compared with the chlorhexidine.

Background: Laser therapy, along with the use of fluoridated compounds is a novel technique suggested for caries prevention. Casein phosphopeptide amorphous calcium phosphate (CPP-ACP) is another product suggested for this purpose. This study compared the effect of CPP-ACP and fluoride with/without Erbium, chromium-doped yttrium, scandium, gallium, and garnet laser irradiation on enamel microhardness of permanent teeth. Materials and Methods: This in vitro experimental study evaluated 35 extracted third molars. The teeth were decoronated, and the crowns were split into buccal and lingual halves. The samples were randomly divided into seven groups (n = 10) of GC Tooth Mousse, MI Paste Plus, laser, fluoride varnish, laser + GC Tooth Mousse, laser + MI Paste Plus, and laser + fluoride varnish. The baseline microhardness was measured before the intervention. After the intervention, the samples were kept in artificial saliva for 1 h and were then immersed in the demineralizing solution for 3 h followed by 21 h of immersion in the remineralizing solution for a total period of 12 days. Finally, the teeth were kept in the remineralizing solution for 2 more days. The secondary microhardness of the teeth was then measured. Data were analyzed using the Shapiro–Wilk test, two-way ANOVA, and Tukey's Honestly Significant Difference test. Results: The fluoride varnish (14.31%) and laser + fluoride varnish (18.79%) groups experienced minimum reduction in microhardness, while the GC Tooth Mousse group experienced maximum reduction in microhardness (91.64%) (P < 0.001). Laser irradiation before the application of remineralizing agents increased the microhardness only in laser + GC Tooth Mousse group (P < 0.001). Conclusion: Fluoride varnish increased the enamel microhardness, while GC Tooth Mousse had no such effect. Laser therapy before the application of remineralizing agents did not significantly enhance enamel resistance to demineralization.

Background: This study aimed to evaluate the use of artificial teeth for endodontic training for dental students. Materials and Methods: The following aspects of the artificial teeth were approved by the endodontists in Isfahan University of Medical Science: internal and external anatomy; coronal pulp chambers regarding their size, shape, and canal path; the root canals regarding their size, shape, and position; filling the pulp chamber and root canals by considering the texture, quantity, color, and ease of handling; and resin hardness and visualization of the radiographic image. Results: The results showed favorable opinions regarding the internal and external anatomy, coronal pulp chamber, root canal (s), handling, and radiographic imaging. The contents of the pulp space and hardness of the teeth were satisfactory. Conclusion: The artificial teeth tested have the potential to replace the natural teeth in preclinical training.

Background: The aim of this study was to investigate whether boron nitride (BN) and BN–chromium (BN–Cr) coatings applied with the sputtering method would change the characteristics of hardness and discoloration of the ceramic veneer surface. Materials and Methods: In this experimental study, thirty disc-shaped cores (10 mm in diameter and 0.8 mm in thickness) were prepared. Three different ceramic systems, IPS Empress (E) (Ivoclar Vivadent, Schaan, Liechntenstein), IPS e.max Press (EP) (Ivoclar Vivadent, Schaan, Liechntenstein), and Turkom Cera (T) (Turcom-Ceramic SDN-BHD, Kuala Lumpur, Malaysia), were tested, each with n = 10. The specimens were divided into two subgroups (n = 5) according to the coating on the veneering ceramic: BN or BN–Cr. The Vickers hardness and color differences (ΔE) values were measured before and after coating. Surface analysis was performed with X-ray diffraction, X-ray photoelectron spectroscopy, and scanning electron microscopic. The Wilcoxon signed-rank test was performed to compare hardness values. The Kruskal–Wallis test was performed to compare ΔE values among all groups. The post hoc tests was used after Kruskal–Wallis, with level of statistical significance set at P ≤ 0.05. Results: BN–Cr coating statistically significantly increased the hardness of all types of ceramics (P < 0.05). BN coating did not change the hardness statistically significantly (P > 0.05). The mean ΔE values indicated clinically noticeable (over the limit of 3.7) color change in all groups except for the EP-BN and T-BN groups. Conclusion: Although BN–Cr coating in this thickness had a negative effect on color, it increased the hardness of the ceramics and could be useful in the palatal region.

Background: This study investigated the influence of erbium-doped: yttrium aluminum garnet (Er:YAG) laser on the pull-out fracture load of fiber-reinforced composite (FRC) posts luted to dentin with different resin cements. Materials and Methods: In this in vitro experimental study, 90 premolars were endodontically treated. The post spaces were prepared, and the teeth were divided into three groups dependent on the cement applied for luting FRC posts: Group 1: An etch-and-rinse system, Group 2: A self-etch cement, and Group 3: A self-adhesive cement. After 6 months' storage and thermocycling, each group was divided into three subgroups (n = 10) according to the treatment applied for removing the posts; subgroup 1: Control, subgroup 2: Treatment with Er:YAG laser at 250 mJ, 20 Hz, and subgroup 3: Treatment by Er:YAG laser at 300 mJ, 10 Hz. The pull-out load was recorded in Newton. The data were analyzed by two-way ANOVA at P < 0.05. Results: The fracture load was significantly affected by the cementation group (P = 0.005) and treatment subgroup (P = 0.008). The pull-out load of self-etch cement was significantly greater than that of the self-adhesive and etch-and-rinse systems (P < 0.05). Treatment with Er:YAG laser caused a significant reduction in pull-out load of FRC posts (P < 0.05). Conclusion: The fracture load of fiber posts is influenced by the type of cement and treatment applied. Post removal would be less challenging when using a self-adhesive or conventional etch-and-rinse cement or using Er:YAG laser at the FRC-resin interface.

Background: Remineralization is currently considered a treatment option for many clinicians. The present study was conducted to compare the effect of three remineralizing agents on microhardness of initial caries lesions in primary teeth. Materials and Methods: In this in vitro study, 96 enamel samples were prepared. Microhardness was first measured for all the samples using the Vickers microhardness test. After developing the initial caries lesions, the microhardness of all the demineralized samples was measured, and the samples were then divided into four groups (n = 24). Casein phosphopeptide–amorphous calcium phosphate in Group 1, Remin Pro in Group 2, and acidulated phosphate fluoride gel in Group 3 were placed on the samples for 4 min. The control group received no treatments. The microhardness of the samples was measured again following a pH cycle of 5 days. The data were analyzed by ANOVA and the post hoc test at the significance level of P < 0.05. Results: The mean microhardness reduced significantly in all the groups following the development of initial caries lesions and after the pH cycle of 3 days (P < 0.001). After the remineralization and pH cycle of 5 days, the mean microhardness was significantly lower in the control group compared to the other three groups (P < 0.001) and had increased in the three treated groups. The microhardness recovery rate also increased in the treated groups compared to the control group, but no significant differences were observed between the three groups themselves (P > 0.05). Conclusion: Remin Pro can be used as an effective substance for preventing tooth caries in children.

Canalicular adenoma (CA) is a rare, benign salivary gland tumor that has special tendency to occur in the upper lip. Buccal mucosa is the second most common site. It occurs more often in older patients with peak prevalence in the seventh decade of life. A definitive female predominance has been reported. According to the latest English published literature, 531 cases of CA have been reported. We present a case of CA of the hard palate that presented in a 29-year-old female patient. The histopathological and immunohistochemical findings showed typical features of CA and intense expression of pan-cytokeratin and S-100 protein. We also review its differential diagnosis from other salivary gland tumors.

Background: The maximum conservation of tooth structure and the use of restorative materials with elastic modulus close to the dental structure may promote greater longevity of the tooth/restoration complex. This study was conducted to evaluate the effect of cavity design and material type on fracture resistance and failure pattern of molars restored by computer-aided design/computer-aided manufacturing (CAD/CAM) inlays/onlays. Materials and Methods: In this in vitro study, 55 human maxillary molars were embedded in resin blocks and divided into control group (CG) and five main groups: Group 1: Inlay, Group 2: Conventional onlay/mesiobuccal (MB), Group 3: Conservative onlay/MB, Group 4: Conventional onlay/MB and distobuccal (DB), and Group 5: Conservative onlay/MB and DB. Then, each group was divided into two subgroups: (A) CeraSmart (CS) and (B) Katana Zirconia (KZ). Restorations were cemented by RelyX Ultimate and then thermocycled. The universal testing machine was used to measure fracture loads. Failure was determined using a magnifying lens. Data were statistically analyzed using ANOVA followed by Tukey's post hoc test (P < 0.05). Results: Group 5 showed the highest significant fracture load, whereas the least significant value was recorded in Group 2. KZ recorded higher significant fracture loads than CS in all tested groups. Groups 1, 2, and 3 restored by CS showed lower fracture load than CG, but the difference was insignificant with Group 1. CS restorations showed restorable failure, while unrestorable pattern was predominant in KZ restorations (P < 0.05). Conclusion: KZ inlays and onlays can be used safely in terms of fracture resistance as both have values exceed the physiologic requirements. CS inlays and onlays/MB and DB are of fracture resistance comparable to intact teeth. The use of conservative onlay design with more cusp coverage guarantees better resistance of CS restorations. Being force absorbing material, the predominant failure of teeth restored by CS was restorable.

Background: The relative high caries risk of pits and fissures highlights the importance of protecting these areas. The aim is to determine the effect of sodium hypochlorite (NaOCl) on the shear bond strength (SBS) of resin-based pit and fissure sealant (RBPFS) material to enamel using resin-modified glass ionomer cement (RMGIC) and fluoride-releasing self-etch resin (FRSE) adhesives. Materials and Methods: In this in vitro study extracted third molar teeth without carious lesions or defects were divided into five experimental groups (n = 20). Group A: (Control group) etch (35% phosphoric acid) for 15 s and RBPFS applied. Group B: Etch for 15 s, FRSE and RBPFS applied. Group C: Pretreated with 5% NaOCl and similar steps to Group B. Group D: Etch for 15 s then RMGIC bonding agent and RBPFS applied. Group E: Pretreated with 5% NaOCl and then similar steps to Group D. SBS was determined using a universal testing machine. The tested specimens were examined under a field-emission scanning electron microscope. Data were analyzed using one-way ANOVA and post hoc Tukey's tests (P=0.05). Results: A statistically significant difference between the test groups was observed; Group C showed the highest SBS mean value (7.52 ± 2.74 MPa) and Group D showed the lowest (4.48 ± 1.81 MPa) (P < 0.001). Pretreatment with NaOCl increased the SBS of fissure sealant when Riva bond LC was used (P = 0.049). Conclusion: The use of NaOCl as pretreatment can increase the SBS of RBPFS to enamel using RMGIC adhesive. FRSE adhesive did not show improvement in SBS values using pretreatment.

Background: Various factors affect child behavior in different situations such as in a dental clinic. The purpose of this study was to investigate the relationship between temperament and child behavior during routine dental treatment. Materials and Methods: The present study is a descriptive-analytic study that included 199 children aged 3–7-years from patients referred to a dental clinic of Guilan University of Medical Sciences in 2017–2018. The Children's Behavior Questionnaire, which is specific to children aged 3–7 years, was used to assess children's dental temperament. Children's behaviors during dental treatment were recorded using Frankl scale. Finally, the data were analyzed by the SPSS-16 statistical software. Results: About 47.9% of the samples were female, with a mean temperament score of 4.79 which was significantly higher than males (P < 0.05). Almost 2.4% of children had completely negative behaviors and 2.8% had a completely positive behavior. The mean scores of fear (P = 0.008) and anger (P = 0.004) in children with completely negative behavior were higher than those with completely positive behavior. Moreover, the average scores of inhibitory control (P = 0.003) and perceptual sensitivity (P = 0.001) in completely positive children were higher than completely negative children. Conclusion: The results of the present study showed that girls had a better mean score of temperament than boys. The inhibitory control and perceptual sensitivity in completely positive children were significantly higher than negative children. In addition, a higher mean score of fear and anger was observed in completely negative children.

The current global spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its associated coronavirus disease (COVID-19), has grasped the attention of entire international community and has caused widespread public health concerns. All the efforts taken globally to curtail the novel COVID-19; the outbreak is still on a rise owing to the community spread pattern of this infection. COVID-19 is a zoonotic infection that, like other coronavirus infections, is believed to have been originated in bats and pangolins, and later transmitted to humans. Once in the human body, this coronavirus (SARS-CoV-2) is abundantly present in nasopharyngeal and salivary secretions of affected patients and its spread is predominantly thought to be respiratory droplet in nature. Dental professionals may soon encounter patients with suspected or confirmed SARS-CoV-2 infection and will have to act carefully not only to provide care but at the same time prevent spread of infection. Thus, the aim of this article is to provide a brief overview of the epidemiology, symptoms and routes of spread of the novel COVID-19 infection. In addition to this, specific recommendations for dental practice are prescribed for patient screening, infection control strategies, and patient management protocol.

Background: Glass fiber posts, along with their esthetic properties, may have a better stress distribution than cast posts, Therefore, the aim of the present study was to investigate the effect of glass fiber, casting, titanium, and zirconia posts on stress distribution in maxillary central tooth treated with different amounts of ferrule using finite-element analysis. Materials and Methods: In this experimental study, three-dimensional models of maxillary central incisors that have undergone root canal treatment were designed. Then, the models were divided into four groups according to the type of post (Ni-Cr casting, glass fiber, titanium, and zirconia) used. Zirconia monolithic crowns were used in all the four groups. Ferrule heights were repeated at 0 and 2 mm in all models. Models were entered into COMSOL Metaphysics software. Then, the force of 100 N with the angle of 135° on the palatal surface was applied to the longitudinal axis of the tooth, and the stress distribution in the models was investigated. Results: Maximum stress was observed in the middle third of posts. Stress distribution in glass fiber post was better than zirconia and casting posts. Stress accumulation in models with zirconia, titanium, and casting posts was also found in the site between the middle third and coronal third, whereas in models with glass fiber post, stress accumulation was found between the crown and the cemento-enamel junction. In models without ferrule, stress accumulation was observed in one-third of the coronal, especially in glass fiber posts. Conclusion: The post material and ferrule height affected stress concentration. The stress in the cervical area of the dentin was more for glass fiber post when compared to other posts. The use of glass fiber post in teeth with no ferrule results in lower stress along the post, but greater stress in the simulated tooth region.

Background: This study was conducted to compare the shear bond strength (SBS) of orthodontic brackets to amalgam surfaces by two surface treatment methods, two different adhesives, and one intermediate resin and also to evaluate surface roughness after two preparation methods as well as bond failure mode. Materials and Methods: In this in-vitro study forty-eight amalgam samples were randomly allocated to four groups. In Groups 1–3, specimens were sandblasted with 50 μm aluminum oxide, followed by application of Alloy primer in Groups 1 and 2. In Group 3 Alloy primer had not used. In Group 4, samples were prepared by silica coating using a silane coupling agent. Surface roughness analysis was performed in 10 additional samples after two surface treatments. The brackets in Group 1 were bonded with Transbond XT and those in other groups were bonded with Panavia V5. All specimens were examined for SBS following 5000 times thermocycling at 5°C–50°C. Modified adhesive remnant index was utilized for the bond failure mode. Data analysis was done by one-way analysis of variance, post hoc Tukey, Kruskal–Walli and Mann–Whitney U tests. Statistical significance was set at P < 0.05. Results: The findings indicated the mean SBS were low (ranged from 0.19 to 4.66 MPa) and significantly lower in Group 3 than in Group 4 (P = 0.009). Bond failure occurred in adhesive/amalgam interface in nearly all samples. Silica coating produced significantly lower roughness than sandblast (P = 0.009). Conclusion: Silica coating had a significant higher bond strength than sandblast without application of Alloy primer. However compared to sandblast with Alloy primer, silica coating did not significantly improve the bond strength. Chemical bond between PanaviaV5 and sandblasted amalgam was not considerable.

Background: There is little information concerning the biocompatibility of mouthwashes containing metal nanoparticles. This study was conducted to assess the biocompatibility of colloidal solutions containing zinc oxide (ZnO), copper oxide (CuO), titanium dioxide (TiO2), and silver (Ag) nanoparticles compared with chlorhexidine (CHX) in a culture of human gingival fibroblasts (HGFs). Materials and Methods: This was an in vitro, experimental study. Nanoparticles, including ZnO, CuO, TiO2, and Ag, were purchased and added to a water-based solution to produce mouthwashes. The colloidal solutions and CHX were prepared at the minimum inhibitory concentration (MIC) against Streptococcus mutans and Streptococcus sanguis. Cytotoxicity was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay on HGFs at the concentrations of MIC, 0.1 MIC, and 0.01 MIC. To determine apoptosis, DNA fragmentation was assessed as “sub-G1” peak on DNA content histogram. The data were analyzed using repeated measures analysis at P < 0.05. Results: At all concentrations, the highest and lowest mean of cell viability was related to TiO2 and ZnO groups, respectively. At MIC, the mean cell viability was significantly greater in the TiO2 group than the other groups (except the Ag group) (P < 0.05). At the concentration of 0.01 MIC, the mean cell viability in the colloidal solution containing ZnO nanoparticles was significantly lower than the other solutions (P < 0.05). The CHX and CuO-containing solution displayed the highest rate of apoptosis among the groups. Conclusion: The TiO2-containing solution can be suggested as a suitable alternative to CHX to provide antiseptic effects with minimal toxicity.

Background: Various iron drops are prescribed to children to prevent iron-deficiency anemia. The current study aimed to evaluate and compare the physicochemical profile of iron drops and the effect of these medicines on the color of primary teeth. Materials and Methods: On the commencement of this experimental study, the pH and viscosity of five types of iron drops were measured. For the purpose of the current study, sixty healthy anterior deciduous teeth were provided; thereafter, they were assigned to five groups and then exposed to iron drops. The color and color difference of each specimen were measured by VİTA Easyshade Compact after 2 weeks. The amount of absorbed iron was determined by atomic absorption. The data were analyzed using two-way ANOVA and Tukey's test (P < 0.05). Results: As evidenced by the obtained results, all medications demonstrated acidic pH and discoloration. The viscosity values of iron drops were reported to be within the range of 2.07–33.58 cP. Based on the results of Pearson's correlation coefficient test, discoloration showed a correlation with pH and atomic absorption (P < 0.05). Conclusion: Analyzed iron drops displayed low pH and discoloration higher than 3.3 which can be easily distinguished with naked eyes. Medicine labels should include warning statements on the feasibility of dental discoloration and erosion.

Background: Most parents believe that teething is associated with some symptoms and commonly use Internet to gain more information about the health of their children. Pediatricians can also serve as a source of information for health-related requirements of parents. This study aimed to compare the information provided by pediatricians regarding tooth eruption and the information available in Persian-language websites. Materials and Methods: This descriptive, analytical, cross-sectional study was performed in two phases. In the first phase, the questionnaire was designed by 85 pediatric pediatricians in Isfahan about children's dental eruption and internet resources. The second phase was the study of 22 Persian websites about children's tooth eruption using Google search engine and the keywords “tooth eruption,” “tooth eruption symptoms.” Then a checklist was prepared to evaluate the quality and completeness of the content. Data were analyzed by the Chi-square test and Fisher's exact test using SPSS (P < 0.05). Results: None of the retrieved websites had the health on the net code of conduct. The most common symptoms of teething reported by both pediatricians and websites included irritability, drooling, gingival tenderness, chewing tendency, decreased appetite and sleep disturbances. In non-pharmacological methods to control the symptoms related to tooth eruption in both groups, embracing the baby (P < 0.001), using soft tooth ring (P = 0.049) and chewing hard foods (0.016 P = significant. Use of oral pain medication (P = 0.01) and sedatives and medications (P = 0.04) were significant in the medication method. Conclusion: None of the websites reviewed had a valid source code and author. Although websites cannot replace the instructions of pediatricians regarding growth and development of children and their teething, supplementary information can be acquired from high-quality websites because there seems to be no significant difference between these two information sources regarding tooth eruption symptoms and their management.

Background: Nickel-titanium (NiTi) open coils are common tools in fixed orthodontic treatments to apply light and continuous forces. Their favorable mechanical properties and their relatively high cost have prompted many clinicians to decide to reuse them. Aim: The present study aimed to evaluate the effect of 10% hydrochloric acid (HCl) and 5.25% sodium hypochlorite (NaClO) solution and sterilization, on the unloading force of NiTi open-coils. Materials and Methods: This experimental in vitro study consisted of 160 NiTi open coils from two brands of Highland Metals and Masel were provided. Each group was randomly divided into four subgroups: control, three rounds of immersion, three rounds of autoclave sterilization, and three rounds of immersion and autoclaving. Each round of immersion process included 1 min in 10% HCl, followed by 5 min in 5.25% NaClO. Spring was compressed for 4 mm. Then, the unloading forces of each spring were recorded at 4, 3, 2, and 1 mm of compression, respectively. The data were analyzed with SPSS (P < 0.05), using one-way ANOVA and independent t-test. Results: One-way ANOVA showed a significant difference in the 2-mm compression of Group 1 and 3-mm compressions of Groups 1 and 2 compared to the control group in the Highland metals brand (P < 0.04, P < 0.014, and P < 0.007, respectively). There was no significant difference between the different compressed lengths and groups in the Masel brand. Conclusion: One-minute immersion in 10% HCL and 5-min immersion in 5.25% NaOCl, followed by autoclave sterilization, even after repeating the process three times, did not significantly change the force properties of NiTi open springs. Therefore, the re-use of these springs with the above-mentioned method as preparation can be recommended.

Background: Various systemic diseases can cause oral manifestations, such as inflammatory bowel disease (IBD). This study is designed to investigate the frequency of oral manifestations in patients with IBD referred to health centers and offices in Isfahan in 2018. Materials and Methods: This cross-sectional study was done among 161 patients suffering from IBD in Isfahan, Iran. They were chosen by the systematic randomized sampling. Finally, the data were analyzed using the logistic regression test in the SPSS software. Significance was assigned at P < 0.05. Results: The number of patients with ulcerative colitis and Crohn's syndrome was, respectively, 119 persons (73.9%) and 42 persons (26.1%). Oral manifestations were seen among 52 (32.3%) of the samples. The frequency of oral manifestations was 35.6% (31 cases) in males and 28.4% (21 cases) in females. Oral manifestations were seen in 29.4% of patients with ulcerative colitis and 40.5% of patients with Crohn's disease. Based on the logistic regression, there was a statistically significant relationship between the use of azathioprine and mesalazine with oral manifestations (P < 0.05), whereas the severity of disease and smoking were not statistically significantly related to oral manifestations (P > 0.05). Conclusion: The severity of the disease was not significantly correlated with oral manifestations, which are in agreement with the results of previous studies. It was also found that among patients with IBD, the oral aphthous ulcers can appear 1–3 years before the diagnosis of the disease. Besides that, some of the drugs used to treat the disease have a significant relationship with oral manifestations.

Background: This study assessed the antimicrobial activity of Biodentine, mineral trioxide aggregate (MTA), and calcium-enriched mixture (CEM) cement against Enterococcus faecalis, Streptococcus mutans , and Candida albicans. Materials and Methods: In this in vitro study, microbial suspensions were inoculated onto agar plates. The antimicrobial effects of MTA, Biodentine and CEM cement were assessed against E. faecalis, S. mutans, and C. albicans by the agar diffusion test. In each experimental group, 7 plates containing 3 wells were prepared and immediately filled with freshly mixed cements. Positive and negative control plates were prepared with/without the bacterial suspension, respectively. After 2 h of preincubation at room temperature, the plates were incubated at 37°C for 24 h. The diameter of growth inhibition zones was measured after 24 h. Data were analyzed using ANOVA and Tukey's test (α = 0.05). Results: Biodentine showed strong antimicrobial activity against all three microorganisms with an average inhibition zone of 9.10 mm. The inhibitory effect of Biodentine on E. faecalis and C. albicans was significantly superior to that of the other two cements (P < 0.05). MTA and CEM cement showed significantly higher antimicrobial activity against S. mutans (P < 0.05). The antimicrobial effects of Biodentine on S. mutans and E. faecalis were significantly greater than on C. albicans (P < 0.05). Conclusion: All cements revealed antimicrobial properties against the tested microbial strains. Biodentine had stronger antimicrobial effects against E. faecalis and C. albicans compared with MTA and CEM cement. Furthermore, the largest inhibition zones around all three cements belonged to S. mutans.

Background: The purpose of this study was to compare the microhardness values of ProRoot mineral trioxide aggregate (MTA), Biodentine, and total fill root repair material (TF-RRM) Putty at varying pH and times. Materials and Methods: In this laboratory experiment, materials were mixed and placed in cylinder blocks with internal dimensions of 6 mm × 4 mm. Ten samples of each material were soaked in buffered solutions of butyric acid with 4.4, 5.4, 6.4, and 7.4 pH values and stored at 37°C in 100% humidity. The samples were submitted to the microhardness test at the end of 1 week and then 1 month. Multivariate analysis of variance and Tukey honestly significant difference tests were carried out to compare the mean values at a significance level of P < 0.05. Results: Low pH caused a significant decrease in the microhardness values of all samples. Surface microhardness increased with time (P < 0.0001). The microhardness values of Biodentine were significantly greater than those of ProRoot MTA and TF-RRM putty (P < 0.0001). The lowest microhardness values were recorded for TF-RRM putty groups regardless of the pH of the environment and the evaluation time. Conclusion: An acidic environment impaired the surface microhardness of all root repair materials tested. Overall, the mean surface microhardness of TF-RRM Putty was lower than those of ProRoot MTA and Biodentine. Biodentine showed the greatest microhardness values at all pH values, regardless of the evaluation time.

Background: The “All-on-four” concept for treatment of edentulous arches incorporates four implants that are placed in between mental foramina in the mandible. The prosthetic framework is an important parameter in stress/strain concentration at the implants, prosthesis, and the underlying bone. Materials such as titanium, zirconia, and carbon fibers have been used for fabrication of framework in the past. The aim of this study was to analyze the effect of framework materials in the “All-on-four” implant system. Materials and Methods: Finite element three-dimensional (3D) model of edentulous mandible was simulated using a computerized tomographic scan data of an edentulous patient. Threaded implants were replicated along with the abutments using 3D modeling software and the framework was designed and simulated using material properties of titanium, zirconia, and polyetheretherketone (PEEK). Axial and nonaxial load of 200 N was applied at the abutment region of right distal implants. The computer-generated numerical values were tabulated and analysed by ANSYS software. Results: Principal strain, von Mises stress and micromotion were assessed in the peri-implant bone region to evaluate its stress condition. Zirconia framework showed the least stress/strain values at axial and oblique loading. Maximum strain values were seen at the PEEK framework material. Zirconia framework in all models showed the least micromotion/displacement. Conclusion: The stress distribution pattern at implant–bone interface was influenced by the framework material used. The framework material, loading site, and direction of forces influenced the stresses and displacement at the bone–implant interface.

Background: In December 2019, a series of unusual pneumonia has been reported in Wuhan, China. This pneumonia was related to beta-coronavirus cluster which was named COVID-19. The aim of this study is to review the published paper on COVID-19 protections guide lines and attempt to summarize different suggested guide lines in order to help dental/oral healthcare to have better protection against COVID -19 Materials and Methods: An electronic literature search was conducted via google scholar, PubMed, and dental associations' of different countries' website using the key word “COVID-19, Dental team, Guide lines and Recommendation”.A total of seven guidelines were found suitable to be included in this review. Conclusion: Individuals with 'possible' or 'confirmed' COVID-19 should not be seen for routine dental care. Multi-step approach should begin before the patient arrives on the office and includes guidance regarding their arrival and it should be completed duration of the affected patient's presence in the practice. Accurate travel history, fever or history of fever, acute respiratory infection and severe respiratory infection without fever requiring hospitalization should be checked by staff via patients telephoning to make an appointment and finally the primary infection control goal is to prevent transmission of disease. These treatment guidelines are based on very limited evidence from the literature and should be revised as soon as more evidence about the infection control advices for dental team regarding COVID-19.

Tricho–dento–osseous (TDO) syndrome is a multisystem congenital disorder that is known by bone, skin, and hair abnormalities. Primitive studies show different varieties of manifestations related to this disorder, which involve sclerotic bones, nail involvement, enamel hypoplasia, mandibular prognathism, and taurodontism. Although exploring different TDO cases revealed genetic mutations in all of them, they have many variations in phenotypic view. In this study, we report a case whose primary diagnosis was alopecia and came for extraction of her third molars, but after clinical and radiographic examination, it was found that the cause of her disease was something different.

Background: Interaction between 2% lidocaine HCl (with and without adrenaline) and sodium hypochlorite (NaOCl) resulted in a toxic precipitate formation. The aim of this in vitro study was to assess the interaction between 4% articaine hydrochloride with adrenaline (AHa) and commonly used endodontic irrigants 3% NaOCl, 2% chlorhexidine (CHX), and 17% ethylenediaminetetraacetic acid (EDTA) using spectroscopic analyses. Materials and Methods: In this in vitro study, 3% NaOCl, 2% CHX, and 17% EDTA were mixed with 4% AHa individually. 1.7 ml of 4% AHa from the cartridge was mixed with 1.7 ml of each test irrigants. The solutions were subjected to a preliminary ultraviolet spectroscopic (UVS) analysis to assess forpotential interactions (if any). If the interaction was detected, the test solutions were further subjected to nuclear magnetic resonance (NMR) analysis for characterization. The precipitate formed (if any) was then subjected to NMR analysis. Results: UVS analysis revealed a bathochromic shift when 3% NaOCl and 2% CHX were mixed with 4% AHa, respectively. This shift was not observed when EDTA was mixed with 4% AHa. 1H and 13C NMR spectra confirmed the interaction between 3% NaOCl with 4% AHa, which resulted in a precipitate formation, methyl 3-amino-4-methylthiophene-2-carboxylate (MAMC). The analysis of 1H NMR spectra showed peaks at 7.1 ppm, 2.21 ppm, and 9.93 ppm, respectively, which corresponds to aromatic ring protons. A peak at 3.8 ppm was assigned to methyl proton of methyl ester. The characteristic appearance of peaks at 14.82 and 51.16 ppm corresponds to aliphatic carbons. The five peaks occurring at 126, 134.5, 139.2, 156.5, and 162.9 ppm correspond to the aromatic carbon atoms present in the thiophene unit. NMR spectra revealed no interaction between 2% CHX and 4% AHa. 1H and 13C NMR spectra confirmed that 3% NaOCl interacted with 4% AHa, leading to the formation of a precipitate MAMC. Conclusion: 3% NaOCl interacted with 4% AHa leading to the formation of a precipitate MAMC which is reported to exhibit the least toxicity. Until the precipitate is studied further, it would be advisable to avoid the immediate use of NaOCl following administration of intrapulpal anesthetic solution with articaine hydrochloride (with adrenaline).

Background: The etiology of temporomandibular disorders (TMDs) is complex and associated with multiple predisposing and initiating factors. Articular eminence morphology and steep eminence inclination have been postulated as the etiological factors, but there has been no clear evidence of association of morphology of the temporomandibular joints (TMJ) complex as a probable predisposing factor in the pathogenesis of TMDs. Materials and Methods: This was a cross-sectional, case–control study, and cone-beam computed tomography scans, and the evaluation was performed for 60 joints in 30 patients with symptomatic TMDs and for 40 healthy joints of 20 age-matched patients. One-way ANOVA, post hoc, unpaired t-test, Chi-square, and intra-class correlation coefficient test were used to determine the correlation between the TMJ articular eminence inclination, height, condylar bone changes, condyle, and fossa shapes with symptomatic TMDs. The P < 0.05 were considered statistically significant. Results: There was a statistically significant difference of articular eminence inclination and height with a steeper eminence inclination in the control group (P = 0.044*, and 0.035*). The condylar bone changes were found to be significantly more in the TMJ disorder group (P = 0.001*). There was no significant association of condyle and fossa shapes (P = 0.482 and 0.689) and of articular eminence inclination and height with condylar bone changes (P = 0.695, 0.498, 0.192, and 0.823) and condyle shapes (P = 0.389, 0.521, 0.260, and 0.387). The eminence inclination was not associated with fossa shapes (P = 0.471 and 0.086), but eminence height was associated with fossa shapes in the TMJ disorder group (P = 0.043* and 0.111). Conclusion: The results depicted that there was no significant association between TMJ complex anatomy and TMJ disorders in the present study population.

The aim of this work is to describe a case of severe disparallelism between two implants supporting a cement-retained bridge, placed in the maxilla, employing two custom-angled abutments. Fractured abutment screw and fractured abutment involved two implant restorations in the maxilla. Once prosthetic components have been removed, a new prosthetic rehabilitation has been planned. The divergence between the implants was measured, obtaining an angle of divergence of 39°. Then, two custom-angled titanium abutments and two metal-ceramic splinted crowns were realized.

Background: Recently, inequality in dental care has become increasingly popular in both developed and developing countries as a matter of health policy. Thus, the aims of this study were examining inequality in dental care expenditures and assessing the effects of insurance coverage and other variables on these services. Materials and Methods: In this cross-sectional and descriptive-analytical study, we used secondary data of the National Health Accounts that has been conducted in 2008 in Iran. The sample size was 17,239 households in all over the country. All analyses were performed by Stata software using Mann–Whitney test and logistic regression. P < 0.05 was considered statistically significant. To determine inequality in dental services, the concentration index (CI) was used. Results: CI for total dental expenditures was 0.315 and for orthodontics was 0.6. Findings showed that out-of-pocket expenditure for dental care was progressive and there was a significant relationship between total dental expenditure with residence areas (odds ratio [OR] =1.3; P > 0.001), complementary insurance coverage (OR = 1.3; P > 0.001), family size (OR = 1.46; P > 0.001), and income (OR = 1.3; P > 0.001). Conclusion: Dental expenditures were progressive in Iran, and the rich have paid more share for these services. It seems that implementing insurance programs, changes in the financing of dental care, development of insurance basic benefits package, supporting programs for the poor, adopting educational policies, and promoting oral health for vulnerable people can have an effective role in decreasing inequality in using dental services.

Background: Cryogenic methods have been used to increase the wear, abrasion, corrosion resistance and to improve the strength of metals. The aim of this study was to evaluate the effect of cryogenic treatment on the cyclic fatigue resistance of rotary nickel-titanium (NiTi) instruments. Materials and Methods: In this in vitro study, 20 Hyflex (Coltene, Altstätten, Switzerland) nickel-titanium instruments, size 25, 0.06 taper, were randomly divided into two groups as follows: untreated NiTi rotary files (Group A) and cryotreated NiTi rotary files (Group B). The instruments of Group A were completely immersed in a cryocan containing liquid nitrogen (–196°C) for 24 h. After 24 h, the instruments were removed from the bath and were allowed to return to room temperature gradually. All files were used (at a speed of 500 rpm and a torque of 2.5 Ncm) in an artificial canal with a 60° curvature until fracture. Time to failure was recorded with a stopwatch in seconds and subsequently converted to number of cycles to fracture (NCF). Groups were compared using the independent-samples t-test. The level of statistical significance was set at 0.05. Results: Mean NFCs in Group A and B were 1576 and 1395, respectively. However, statistical analysis showed that there was no significant difference between the groups (P = 0.2). Conclusion: Deep cryotherapy of NiTi endodontic files cannot improve the cyclic fatigue resistance of HyFlex files, but further studies are required to evaluate these cryogenically treated NiTi files clinically.

Background: Light curing of resin composite is associated with a thermal rise that may have harmful effect on the health of the vital pulp. In addition, desirable polymerization is important to achieve mechanical properties and clinical function. The purpose of this in-vitro study was to compare the thermal rise under normal dentin during photopolymerization and degree of conversion (DC) of bulk fill and conventional resin composite using continuous high- and soft-start mode. Materials and Methods: In this in-vitro study, Cl I cavities with a dimension of 4 mm × 4 mm × 4 mm and remaining dentin thickness of 1 mm were prepared on 56 extracted human molars. The temperature rise during the light curing of conventional resin composite (Tetric N Ceram, Ivoclar Vivadent) by incremental filling technique and bulk-fill resin composite (Tetric N Ceram Bulk Fill, Ivoclar Vivadent) by bulk-filling technique were measured with a K-type thermocouple wire. DC of both resin composites was measured using Fourier-transform infrared spectroscopy. Data were analyzed using one-way ANOVA, Tamhane and Duncan post hoc, two-way ANOVA at the significance level of α = 0.05. Results: Photopolymerization temperature rise due to soft start mode and the first layer of conventional composite was higher than continuous high mode and bulk-filling technique, respectively (P < 0.001). DC of conventional resin composite was higher than bulk-fill composite (P < 0.001). Conclusion: Soft-start mode produced higher thermal rise than continuous high mode and conventional resin composite showed higher DC than bulk-fill composite.

Background: Gutta-percha has been the predominant root canal filling material which is developed with different taper. Canal obturation fixed with nickel–titanium (NiTi) instruments and tapered gutta-percha master cone and lateral condensation is advantageous because it is clinically effectual and appears to result in a radiographically acceptable outcome. The aim of this in vitro study was to determine the effect of tapered master gutta-percha cone on apical seal of straight and curved root canals using NiTi rotary files. Materials and Methods: In this in vitro study total of 130 mandibular molars were selected and divided into six experimental groups (n = 20) based on the degree of root canal curvatures (0°–20°and 20°–40°) and the taper of master cones (0.02, 0.04, and 0.06). The roots were immersed in the bacterial leakage model and monitored daily for a period of 70 days. Data were analyzed using Kaplan–Meier approach, log-rank test, and Chi-square tests. P < 0.05 was considered statistically significant. Results: The microleakage in the 0°–20° canal curvature using 0.02- and 0.04-tapered master cones was similar and considerably <0.06-tapered master cone (P < 0.05). However, the microleakage in the 20°–40° canal curvature using 0.02- and 0.04-tapered master cones was more than 0°–20° and for 0.06-tapered master cone was <0°–20°, but there was no statistical difference between the use of 0.02-, 0.04-, and 0.06-tapered master cones (P > 0.05). Conclusion: The lateral condensation filling technique using 0.02- and 0.04-tapered master cones is more effective in minimizing microbial leakage in straight canals than 0.06-tapered master cone.

Background: Regarding the prevalence and importance of periodontal disease and the potential of salivary biomarkers for the early diagnosis of these diseases, this study was conducted to compare salivary concentrations of Interleukin-17 (IL-17) and Interleukin-18 (IL-18) in patients with chronic periodontitis and healthy individuals. Materials and Methods: The present research was a descriptive–analytical and also a cross-sectional study. Unstimulated saliva with full-mouth clinical periodontal recordings were obtained from 20 healthy individuals and 20 individuals with chronic periodontitis. The concentrations of salivary IL-17 and IL-18 were determined using the enzyme-linked immunosorbent assays. The nonparametric Mann–Whitney U-test was used for statistical analysis of the findings. Alpha level was set at 0.05. Results: The mean salivary concentration of IL-18 in patients with chronic periodontitis was 143.10 pg/mL, which was higher than the same concentration in healthy controls (78.33 pg/mL), (P = 0.035). The mean salivary concentration of IL-17 in patients with chronic periodontitis and healthy controls was 3.51 and 4.57 pg/mL, respectively, and there was no difference between the two groups (P = 0.283). Conclusion: Within the limitations of the present study, it may be suggested that an elevated salivary IL-18 level in chronic periodontitis patients has the potential to be a biomarker for periodontal tissue destruction.

Background: This in vitro study was conducted to compare the effect of universal bonding application strategy (i.e., self-etch and etch-and-rinse) on marginal adaptation of bulk-fill and conventional composite resins in Class II restorations. Materials and Methods: In this in vitro study sixty sound premolars extracted for orthodontic reasons were selected. The samples were allocated to four groups based on the universal bonding application strategy (self-etch and etch and rinse) and type of composite (bulk-fill and conventional). In each group, boxes were prepared with a depth of 4 mm on the mesial surfaces. Finally, the marginal adaptation of the samples was evaluated under a stereomicroscope. Two-way ANOVA was used to compare the marginal adaptation data in the study. Statistical significance was set at P < 0.05. Results: Considering the type of universal bonding application strategy, there was a statistically significant difference in marginal adaptation. Etch-and-rinse strategy showed better marginal adaptation compared to self-etch strategy (P < 0.001). However, there was no statistically significant difference in marginal adaptation between the two composite resins (P = 0.829). Furthermore, the interaction between the two factors (type of universal bonding application strategy and type of composite resin) was not statistically significant (P = 0.629). Conclusion: Etch-and-rinse bonding application strategy in both the bulk-fill and conventional composite resins exhibited better marginal adaptation compared to self-etch bonding application strategy. However, the difference of marginal adaptation between the two types of composite resins (bulk and conventional) was not significant.

Background: Two-dimensional intraoral radiography is the most common tool for recognizing root fractures. Improving the quality of images by means of enhancement tools can increase the recognition power of them. The aim of this study is to evaluate the effect of digital image enhancement on vertical and horizontal root fractures (HRFs) diagnostic accuracy. Materials and Methods: In this in vitro study, 100 human extracted teeth, involving 50 mandibular premolars and 50 maxillary incisors, were investigated. In total, 25 premolar teeth were vertically fractured and other 25 sound teeth served as testing group. According to the verified methods, 25 incisor teeth were fractured and other 25 teeth of this group served as testing ones. Following, by using the charge-coupled device sensor, preapical digital images were recorded. The original images were altered using reverse-contrast and colorization enhancement tools. Two different observers independently investigated all of the images. Receiver operating characteristic analysis was used to calculate the area under the curve (AUC) and sensitivity and specificity of all images. Data analyzde using receiver operating characteristic (ROC) analysis. Two-ways variance analysis was used to assess differences in the values (P = 0.05 ). Results: AUC and sensitivity and specificity related to the original, reverse-contrast, and colorized images were calculated (0.84, 0.64, 0.99), (0.84, 0.64, 0.96), and (0.82, 0.64, 0.92) respectively, for vertically root fractured images. AUC and sensitivity and specificity related to the original, reverse-contrast, and colorized images were calculated (0.49, 0.44, 0.56), (0.50, 0.44, 0.60), and (0.48, 0.48, 0.48), respectively, for horizontally root-fractured images. Conclusion: The results of the present study revealed that reverse-contrast and colorized enhancement filters cannot be used as critical methods in detecting in vitro vertical and HRF.

Background: Results on the strength and displacement of internal fixation methods for bilateral sagittal split ramus osteotomy are controversial, and some designs have not been adequately studied. Therefore, this study was conducted to compare techniques using bicortical or monocortical screws. Materials and Methods: In this in vitro study, 35 sheep hemi-mandibles were randomly assigned to five groups of seven each: fixation using (1) a 13 × 2 screw, (2) two 13 × 2 screws (arranged vertically), (3) three 13 × 2 screws, (4) 1 plate with 4 holes and four monocortical screws, and (5) a Y-shaped plate and five monocortical screws. Specimens underwent vertical forces until failure. Breakage forces and displacements of groups were recorded and compared statistically. Using one-way analysis of variance (ANOVA) with a Tukey's post hoc test and Kruskal–Wallis test. Level of significance was predetermined as 0.05. Results: Strengths of Groups 1–5 were, respectively, 14.43 ± 4.35, 28.00 ± 8.89, 28.29 ± 8.01, 29.43 ± 8.24, and 61.29 ± 12.38 N, respectively (P = 0.000, analysis of variance). The corresponding displacement extents were 7.98 ± 0.04, 7.85 ± 0.26, 8.00 ± 0.00, 7.35 ± 1.73, and 6.79 ± 2.03 mm (P = 0.298, Kruskal–Wallis test). Conclusion: Use of a single bicortical screw is the weakest method, while Y-shaped plates might provide the highest strength. Using two or three bicortical screws or 4-hole plates might deliver similar strengths.

Background: The ideal maxillofacial prosthesis should have fine and thin boundaries that bind with the surrounding facial structures and possess high tear strength. This study aims to determine the best percentages of nanofiller (TiO₂) and intrinsic pigment (silicone functional intrinsic) that could be mixed in as additives to improve the tear strength of Cosmesil M511 and VST50F silicone elastomers with the least effect on their hardness. Materials and Methods: In this in vitro experimental study, a total of 80 samples, 40 for each elastomer, were fabricated. Each elastomer sample was split into two equal groups to test for tear strength and Shore A hardness. Each group consisted of 20 samples, including 10 control samples without additives and 10 experimental samples with additives (mixtures of 0.2 wt% nano-TiO₂ + 0.25 wt% intrinsic pigment and 0.25 wt% nano-TiO₂ +0.25 wt% intrinsic pigment for the Cosmesil M511 and VST50F silicone elastomers, respectively). Two-way ANOVA and Tukey test were used for comparison; P < 0.05 was considered statistically significant. Results: Significant differences in tear strength were found among all tested groups (P < 0.05). The tear strength of the experimental subgroups significantly increased compared with the control subgroups (P < 0.05). Significant differences in Shore A hardness were also observed among all tested groups (P < 0.05) except between the experimental subgroups of both materials, where a nonsignificant difference was obtained (P > 0.05). Conclusion: Incorporation of select percentages of TiO₂nanofiller and intrinsic pigment into Cosmesil M511 and VST50F silicone elastomers yields improvements in tear strength with a slight increase in hardness.

Background: Post and core treatment is commonly performed for endodontically treated teeth to replace the lost tooth structure and reinforce and protect the remaining dental tissue. This study aimed to compare the effect of three-core building materials on fracture resistance of endodontically-treated teeth restored with fiber-reinforced composite (FRC) posts and ParaPosts. Materials and Methods: This in vitro, experimental study evaluated 108 sound, single-rooted mandibular first premolars extracted for orthodontic purposes. The teeth were randomly divided into nine groups (n = 12) of control (no endodontic or restorative treatment), FRC + Photo Core (Group 2), FRC + LuxaCore (Group 3), FRC + Core Max II with bonding agent (Group 4), FRC + Core Max II without bonding agent (Group 5), ParaPost + Photo Core (Group 6), ParaPost + LuxaCore (Group 7), ParaPost + Core Max II with bonding agent (Group 8), and ParaPost + Core Max II without bonding agent (Group 9). The fracture resistance was measured by applying the load at 45° angle relative to the longitudinal axis of the tooth with a crosshead speed of 1 mm/min using a universal testing machine. Data were through descriptive statistics, Tukey's test, and one-way analysis of variance (α = 0.05). Results: The mean fracture resistance was 454.0 ± 62.7, 410.8 ± 48.3, 365.1 ± 42.1, 423.7 ± 111.7, 392.4 ± 90.0, 292.3 ± 83.9, 242.3 ± 73.4, 278.2 ± 67.9, and 247.3 ± 49.6 N in Groups 1–9, respectively. Group 4 showed the highest fracture resistance, which was significantly higher than this study the value in all ParaPost and control groups (P < 0.05) but had no significant difference with the fracture resistance of other groups (P > 0.05). Conclusion: Fracture resistance is independent of the type of core building material used, and the tested products had no superiority over each other. The mean fracture resistance of FRC post groups were significantly higher than that of ParaPost groups. Furthermore, Core Max II + bonding agent yielded insignificantly higher fracture resistance than Core Max II without bonding agent.

Background: Scaling and root planing (SRP) for the treatment of periodontitis may be less effective in some patients. This study evaluated the effectiveness of local doxycycline as an adjunct to SRP among smokers with periodontitis compared to SRP alone in randomized controlled trials (RCTs). Materials and Methods: For this systematic review and meta-analysis, PubMed and Scopus databases were searched till November 2018 for English publications. RCTs that compared the effect of local doxycycline adjunct to SRP among smokers with periodontitis were selected. Patient characteristics, disease characteristics, and outcome data on clinical attachment level (CAL) and periodontal probing depth at 1, 3- and 6-month follow-up was extracted. Quality of selected studies was assessed by the revised Cochrane Risk of Bias 2.0 tool. Random effects model and trial sequential analysis were performed. GRADE approach was used to assess the quality of evidence. P > 0.05 was considered as statistically significant. Results: Five trials were included in the review. Local use of doxycycline as an adjunct to SRP was effective in gain of 1.1 mm (0.47–1.74, P = 0.091) in CAL at 6 months calculated from two studies. The evidence was of low quality, and at least a total of 866 patients are required for conclusiveness. Conclusion: Local doxycycline as an adjunct to SRP significantly improved clinical attachment in smokers with periodontitis and can be recommended. Studies are required with long-term follow-up and patient-related outcome data.