Background: The aim of this study was to assess the effect of increasing the drilling speed and depth during implant site preparation on bone viability. Materials and Methods: In this prospective cohort study, participants were divided into four groups based on the speed and depth of drilling at the first molar site in the mandible. Participants underwent drilling at Group 1: 1000 rpm and 10 mm depth, Group 2: 1500 rpm and 10 mm, Group 3: 1000 rpm and 13 mm, and Group 4: 1500 rpm and 13 mm. Obtained specimens were assessed histologically to the qualitative measurement of bone viability, and the percentage of vital bone were evaluated by histomorphometric analysis. ANOVA was used to compare age and the mean percentage of vital bone and Tukey's test as post hoc was applied for pairwise comparison of groups. Results: A total of 100 participants were studied in four groups (25 subjects in each group). Histological evaluation revealed a low level of bone viability maintenance in all groups. Histomorphometric analysis showed the mean percentage of vital bone was 9.5 ± 3.91% in Group 1, 8.86 ± 3.84% in Group 2, 8.32 ± 3.80% in Group 3, and 4.27 ± 3.22% in Group 4. A significant difference was noted in the mean percentage of bone viability among the four groups (P = 0.001). Conclusion: It seems that increasing the drilling speed or depth during dental implant site preparation does not affect the mean percentage of cell viability, while the increase in both depth and speed may decrease the percentage of viable cells.

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Background: Surface roughness associated with improper finishing/polishing of restorations can result in plaque accumulation, gingival irritation, surface staining, and poor esthetic of restored teeth. The study aimed to evaluate the efficiency of various finishing and polishing systems and time using various procedures on surface roughness of some esthetic restorative materials. Materials and Methods: In this in vitro study, samples of two composite materials, compomer and glass ionomer cement (GIC) materials, were fabricated. Finishing and polishing were done immediately (n = 40) and after 1 week (n = 40) using four systems (diamond bur + soflex discs; diamond bur + Astropol polishing brush; tungsten carbide bur + soflex discs; tungsten carbide bur + Astropol polishing brush). Surface roughness was measured using surface profilometer. Data were statistically analyzed by t-test (for each material and time period) and one-way analysis of variance followed by Tukey's post hoc (for finishing and polishing systems) at a significant level of P < 0.05. Results: Analysis of time period, irrespective of finishing and polishing system showed that Ra values were greater (P < 0.05) in delayed polishing in GIC > Z100 > Filtek P90 > Dyract AP, suggesting immediate polishing is better. Among the materials, Filtek P90 had the least Ra values indicating the smoothest surface among all materials, followed by Z100, Dyract AP, and GIC. Comparison of polishing and finishing systems irrespective of materials showed that Ra values were lower (P > 0.05) in diamond + Astropol combination whereas diamond + soflex had the greatest Ra values. Conclusion: It might be concluded that: (i) Filtek P90 showed least Ra values followed by < Z100 < Dyract < GIC; (ii) immediate (24 h) finishing/polishing of materials is better than delayed; and (iii) among all these polishing systems, diamond bur–Astropol and Astrobrush showed good surface finish.

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Pharmacological sedation is one of the effective ways of prevention of gag reflex development in patients experiencing anxiety and fright before dental treatment. We are reporting a case where we could successfully eliminate exaggerated gag reflex (intravenous [IV] Gagging Severity Index) in a dental patient using IV sedation with dexmedetomidine. IV administration of dexmedetomidine provided elimination of gag reflex at a depth of sedation for the patient with the Richmond Agitation-Sedation Scale score of −2 and −1. The patient received dexmedetomidine 1.0 μg/kg for 10 min and then a continuous infusion of dexmedetomidine 0.4 μg/kg/h. The use of dexmedetomidine for sedation may be an alternative to other pharmacological agents in patients with dental anxiety accompanied by exaggerated gag reflex.

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Background: The aim of this study was to compare microbial microleakage of class V cavities restored with different materials and techniques using a microbial leakage assessment method. Materials and Methods: One hundred extracted, caries-free, human maxillary premolars were randomly divided into five groups. Group 1: Resin-modified glass ionomer (RMGI), Group 2: Closed sandwich with flowable composite + nanohybrid composite, Group 3: Nanohybrid composite, Group 4: Closed sandwich with RMGI + nanohybrid composite, and Group 5: Flowable composite + nanohybrid composite that were co-cured together (“snow-plow” technique). A microbial penetration method utilizing Streptococcus mutans as an indicator was tested for leakage assessment. Data were analyzed and the significance level was α =0.05. Results: The log-rank test indicated a statistically significant difference in leakage rates among the five groups (P = 0.008). Mantel–Cox log-rank test indicated statistically significant differences in microleakage rates between Groups 1 and 3 (P = 0.029), between Groups 2 and 5 (P = 0.005), and between Groups 3 and 5 (P = 0.002). Conclusion: With respect to the limitations of an in vitro study, our findings suggest that adding a thin layer of flowable composite or RMGI under nanohybrid composite in class V cavities did not decrease the bacterial leakage rate, whereas use of the “snow-plow” technique caused an increase in the microleakage rate.

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Background: There is a two-way relationship between periodontal disease and diabetes. The purpose of this study was to evaluate the clinical and metabolic effects of a xanthan-based chlorhexidine (CHX) gel used as an adjunct to nonsurgical periodontal therapy in Type II diabetic patients with chronic periodontitis. Materials and Methods: Sixty-eight diabetic patients with moderate to advanced periodontitis and glycated hemoglobin (HbA1c) ≥6% were selected. The test group (n = 34) received scaling and root planning (SRP) plus xanthan-based CHX gel. The control group (n = 34) received single SRP. Fasting blood sugar (FBS) and HbA1c tests were done at the baseline and after 3 and 6 months. Data from the study were analyzed using descriptive statistics (mean ± standard deviation and frequency), ANOVA test by SPSS.15 software (SPSS Inc. Chicago, IL, USA). P < 0.05 was considered statistically significant. Results: Patients in test group exhibited a decrease in FBS from the baseline (227 ± 64.97) to the 3 and 6 months follow-up (208 ± 61.95 and 201 ± 61.33; P < 0.001). HbA1cb levels decreased from 7.72 ± 0.99 to 6.20 ± 0.97 and 6.06 ± 1.04 after 3 and 6 months follow-up (P < 0.001), respectively. Reduction of FBS and HbA1c was statistically significant after 3 and 6 months in the control group (P < 0.001). Conclusion: Considering the limitations of this study, the application of CHX gel might improve the effects of nonsurgical periodontal treatment in diabetic patients with periodontitis.

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Background: Nitric oxide (NO) has many functions in wound healing and bone metabolism. This study sought to assess the local effect of aminoguanidine (AG), a selective inducible NO synthase (iNOS) inhibitor, on the rate of bone healing. Materials and Methods: This experimental interventional study was conducted on 36 rats, which were randomly divided into three groups of control, placebo, and AG. Bone defects measuring 5 mm × 5 mm were created in the femur. In control group, bone defects remained empty. A placebo gel was applied to defects in the placebo group. AG gel was placed in bone defects in AG group. New bone formation and healing were assessed using histological and histomorphometric analyses. The healing score and the percentage of new bone formation (total bone mass, immature bone, and mature bone) were compared among the three groups using the Kruskal–Wallis test and analysis of variance, respectively. A P < 0.05 was statistically significant. Results: The mean healing score in AG group (3.17 ± 0.577) was significantly higher than that in control (2.67 ± 0.49) and the placebo (2.58 ± 0.515) groups (P = 0.036). The percentage of new mature (lamellar) bone in AG group (22.06 ± 1.90) was significantly higher than that in control (20.94 ± 2.03) and the placebo (20.53 ± 1.20) groups (P = 0.008). Conclusion: The rate of bone healing was faster in the AG compared to the other two groups. Local application of selective iNOS inhibitors like AG may be efficient as an adjunct in the clinical setting where local bone formation is required.

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Background: Oral submucous fibrosis (OSMF) is a chronic debilitating disease of the oral cavity having premalignant potential and unclear pathogenesis. Recently, myofibroblast has been postulated to play an important role in its pathogenesis and in the process of carcinogenesis. The purpose of this study was to evaluate and compare the presence of myofibroblasts in normal mucosa, different grades of OSMF, and oral squamous cell carcinoma (OSCC). Materials and Methods: The present in vitro cross-sectional descriptive study sample consisted of three groups, including 40 OSCCs, 40 OSMF, and 10 sections of normal oral epithelium taken as control group. Alpha-smooth muscle actin was used to identify myofibroblasts using immunohistochemical technique. P < 0.05 was taken as statistically significant. Results: The presence of myofibroblasts was significantly higher in OSMF cases when compared with normal epithelium specimens. The presence of myofibroblasts was significantly higher in OSCC compared to OSMF cases. A significant difference was not observed between the different grades of OSCC. Conclusion: These findings favor the possibility that OSMF actually represents an abnormal healing process in response irritation caused by areca nut. A significant increase in myofibroblasts in OSCC as compared to OSMF also highlights the possible role it may play in the malignant transformation of OSMF.

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Background: Different techniques are used to evaluate the anatomy of root canal system. The present study was aimed to evaluate the root canal morphology of mandibular premolars using clearing and cone beam computed tomography (CBCT) techniques. Materials and Methods: A total of 182 mandibular first and second premolars were evaluated in vitro using 100 μm CBCT cross sections. The root canal morphology of the teeth was determined based on Vertucci classification in relation to the prevalence of C-shaped canals, lateral canals, and furcation location. Having removed the pulp tissue with NaOCl solution and staining the root canals with India ink, the samples were decalcified with 5% nitric acid and dehydrated with isopropyl alcohol. Finally, the samples were cleared with methyl salicylate. Data were analyzed by SPSS 16 software using McNamara, t-test, and Kappa coefficient. Results: After Type I, the most frequent morphologies in both first and second premolars were Type V followed by Type IV. The prevalence rates of C-shaped morphology in first premolars using clearing and CBCT were 4.4% and 6.6%, respectively. However, no C-shaped morphology was found in second premolars. The maximum and minimum levels of agreement between the two techniques were observed in Type IV and Type V root canal morphologies, respectively. Extra root canals were identified in 25% and 13% of the first and second premolars, respectively. Conclusion: CBCT showed a higher accuracy in determining C-shaped root canal morphology than the clearing technique. It also showed the least accuracy in diagnosing lateral root canals.

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Background: There are some factors which can affect preoperative patient anxiety such as the necessity of procedure, postoperative pain, and patient's conception of his body image. The aim of this study was to assess the relation of patients' preoperative anxiety and postoperative patients' satisfaction in dental implant surgery. Materials and Methods: Dental implants were placed in 40 patients (19 male and 21 female) who were referred to Dental Implant Surgery Department in Imam Reza clinic, during March–December of 2014 in Shiraz. The procedures were performed with or without bone regeneration. Preoperative anxiety was evaluated using Corah Dental Anxiety Scale, and postoperative satisfaction was determined on the basis of pain intensity, bleeding tendency, inability to eating, and overall satisfaction by filling a questionnaire in the 2^nd or 3^rd week after surgery. Data were collected and analyzed using Mann-Whitney test. Results: Preoperative anxiety was detected as high in 10%, mild in 85%, and moderate in 5% of patients. Anxiety and depression score did not differ in both genders. There was no statistical difference between neither level of anxiety nor depression in both high and low educated patients. Postoperative bleeding, difficulty in eating, and overall satisfaction was nearly the same in both genders. Statistical analysis demonstrated a lower pain level and higher pain threshold in men than women (P = 0.007). Patients' age was not related to anxiety, depression, amount of bleeding, pain, and difficulty in eating. Overall dental care satisfaction was similar in both men and women. Conclusion: The results of the study indicated that while anxiety does play a role in the perception of pain by patients undergoing implant surgery, overall patient satisfaction and post surgical outcomes did not significantly differ.

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Agenesis of permanent canines is a rare condition, and that of both maxillary and mandibular permanent canines is extremely rare. It may occur either isolated or in association with other dental anomalies. Reports of such cases are very scarce in the literature. Need for early diagnosis of such conditions should be emphasized because of functional, esthetic, and psychological problems which should be evaluated and treated appropriately. The present paper presents a report of bilaterally missing permanent maxillary and mandibular canines. This case might contribute in the future studies of incidence of agenesis of permanent canines.

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Background: This study was carried out to evaluate the effect of root canal filling on the bond strength of three intracanal posts in the primary incisors. Materials and Methods: Sixty primary incisors were prepared and then divided into two groups (n = 30). The first group canals obturated with zinc oxide eugenol (ZOE) and Group 2 canals obturated with Metapex. Further, the two group categories were divided into three subgroups (n = 10): (1) short composite post (SCP), (2) glass fiber posts (GFPs) cemented with flowable composite, and (3) GFP with glass ionomer cement (GFP + GIC). The push-out test was performed with a universal testing machine. The results were statistically analyzed with two-way analysis of variance.(α = 0.05). Results: The mean bond strength of the first group obturated with ZOE was lower than that of the second group obturated with Metapex (P = 0.046). Moreover, from a statistical point of view, in all three subgroups, the correlation of mean push-out bond strength between SCP and GFP coated with flowable composite was not substantial at P = 0.97. However, the mean bond strength of SCP was in fact significantly greater than that of the GFP coated with GIC since P = 0.034. Conclusion: Using ZOE resulted in the significant reduction of the mean bond strength of the intracanal posts when utilized in the primary anterior teeth. Likewise, SCP and GFP coated with flowable composite showed higher push-out bond strengths for restoring primary anterior teeth.

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