Launching a new fellowship in microrestorative and endodontics for postgraduates in conservative dentistry and endodontics.

Expanding and refining the skill sets of postgraduates specialists is required by the many current and changing demands of dental science education and research. To meet this challenge, the Indian Board of Micro Restorative and Endodontics under the aegis of the Indian Association of Conservative Dentistry and Endodontics has begun a fellowship program in Micro Restorative and Endodontics; the main aim being to improve the knowledge and skills of these specialists empowering them to go a step higher and beyond their areas of specialization. The objectives of the fellowship course are as follows: (1) Achieving necessary skills in managing routine and advanced restorative and endodontic scenarios using modern magnification technology. (2) Constantly enhancing the existing knowledge by pursuing new arenas in magnification technology. (3) Complete understanding and application of cutting edge research in the practice of microrestorative and endodontics. (4) Ensuring the highest possible patient-centric quality of care. Learning experiences shall be provided under the guidance and supervision of competent mentors at predesignated centers all over India. The learning strategies will be through workshops, contact sessions, and learning assignments. The carefully designed curriculum shall prepare the restorative dentists and endodontists, to be an autonomous, effective, safe, and a compassionate professional, who practices collaboratively in a variety of clinical and academic setups, responsive to the current and future needs of the restorative and endodontic health-care system. A passion for microdentistry would be a great way to make a positive difference to your patient care and creative work.

Comparative evaluation of the sealing ability of different obturation systems used over apically separated rotary nickel-titanium files: An in vitro study.

AIM: The study was designed to investigate the sealing ability of two obturation systems (cold laterally compacted gutta percha and Obtura II) over different apically separated rotary nickel-titanium files (RACE and K3 system) using dye extraction method. MATERIALS AND METHODS: Sixty-two mandibular premolars were divided into 2 groups of 30 teeth each, and 2 teeth served as negative controls. In Groups A and B, roots were prepared using RACE and K3 system, respectively, and were further subdivided into 4 subgroups. In subgroups A1, B1 and A2, B2 (n = 10 each), files were separated at 3 mm from the tip in apical 3(rd) of the canal. In subgroups A3, B3 and A4, B4 (n = 5), instruments were not separated. Subgroups A1, A3, B1, B3 and A2, A4, B2, B4 were obturated by lateral condensation method and Obtura II techniques, respectively. The sealing ability of the obturated specimens were tested using dye extraction method. The values for each group were recorded and analysis of variance (ANOVA), Student "t" test (two-tailed, independent), and Leven's test were performed. RESULTS: Group A1 showed significantly less leakage than B1. No statistical significant difference between Groups A2 and B2 and Groups A3 and B3, respectively, were observed. Group A4 showed significantly less leakage than B4. CONCLUSION: Groups obturated with Obtura II showed less leakage than the lateral condensation technique irrespective of presence or absence of fractured NiTi rotary system.

The prevalence of bilateral three-rooted mandibular first molar in Indian population.

INTRODUCTION: The purpose of the present study was to evaluate the prevalence of bilateral three-rooted mandibular first and second molars in Indian population. MATERIALS AND METHODS: A total of 215 patients were screened bilaterally for mandibular first and second molar and 430 samples of periapical radiographs were obtained. The gender, symmetry, and prevalence of three-rooted mandibular first and second molars were recorded. The correlation between left and right side occurrences and distribution were recorded and analysed using Z-test. RESULTS: The results showed that 33 teeth had three-rooted mandibular first molars, 16 male and 17 female (P=0.442). Overall, 21 teeth of right jaw and 12 teeth of left jaw (P=0.103) showed presence of an extra-root. The prevalence of three-rooted mandibular first molars was 7.67% and second molar was 0.23%. The bilateral frequency distribution was 3.72% for the first molar. There was no statistically significant difference between right side and left side mandibular molars. Also, gender did not show a significant relationship with this variant. CONCLUSION: The endodontic treatments of first mandibular molars require a careful clinical approach in Indian population as a high racial prevalence of 7.67% three-rooted molars was found. However, in the same population, 0.23% mandibular second molars had three roots.

Microleakage evaluation of Silorane-based composite and methacrylate-based composite in class II box preparations using two different layering techniques: an in vitro study.

AIM: The aim of this study was to compare the microleakage in Class II box preparations with the gingival margin above and below the cemento-enamel junction (CEJ) restored with Silorane composite and methacrylate composite using two different layering techniques. MATERIALS AND METHODS: Standardized box preparations (mesial box 1 mm above the CEJ and distal box 1 mm below the CEJ) were prepared in 60 upper premolars. The teeth were randomly divided into four groups containing 15 samples each; Group I: Restored with a Silorane composite using an oblique layering technique, Group II: Restored with Silorane composite using a vertical layering technique, Group III: Restored with methacrylate composite using the oblique layering technique, and Group IV: Restored with methacrylate composite using the vertical layering technique. The samples were stored in distilled water, followed by thermocycling and immersed in 2% methylene blue. The samples were sectioned and evaluated for microleakage at the gingival margin. STATISTICAL ANALYSIS: Kruskal-Wallis, Fischer exact test, Wilicoxon test, and Mann-Whitney U test. RESULTS: Silorane composite had significantly lesser microleakage. No significant difference in microleakage was observed above and below the CEJ for Silorane-based composite. CONCLUSION: Silorane composite resin showed lesser microleakage compared to methacrylate composite resin. CLINICAL SIGNIFICANCE: The Silorane-based composites improve the marginal adaptation due to their reduced shrinkage, thereby decreasing the residual stress at the adhesive-tooth interface.

An in vitro evaluation of passive ultrasonic agitation of different irrigants on smear layer removal after post space preparation: a scanning electron microscopic study.

This study evaluated the removal of debris and smear layer after post space preparation using different irrigations and passive ultrasonic agitation. Sixty human premolars were decoronated and post space prepared after endodontic therapy. The samples were then randomly divided into three experimental groups (Groups A, B, C) and one control group (Group D) with fifteen samples in each group. Groups A and B samples were treated with 10 % citric acid and 17 % ethylenediamintetraacetic acid (EDTA), respectively and passive ultrasonic agitation was done, rinsed with sodium hypochlorite and finally flushed with saline. Group C samples were conditioned with 36 % phosphoric acid and then rinsed with saline. The control group was treated with 3 % sodium hypochlorite, passive ultrasonic agitation done and flushed with saline. The samples were sectioned and evaluated for debris and smear layer removal under scanning electron microscope. 10 % citric acid showed the best removal of smear layer when compared with 17 % EDTA and 36 % phosphoric acid, but was not statistically significant (p > 0.05). The difference in scoring for debris and smear layer removal in the coronal, middle and apical third of post space of experimental groups in comparison with control group was statistically significant (p < 0.001).

The reinforcement effect of polyethylene fibre and composite impregnated glass fibre on fracture resistance of endodontically treated teeth: An in vitro study.

AIM: The aim of this study was to evaluate the fracture resistance of endodontically treated maxillary premolars with wide mesio-occluso-distal (MOD) cavities restored with either composite resin, or composite resin reinforced with different types of fibres. MATERIALS AND METHODS: Fifty human maxillary premolars were selected. Five intact teeth served as positive controls. Endodontic therapy was carried out in the remaining forty-five teeth. Standardized MOD cavities were prepared in all the teeth. The teeth were restored with a nanocomposite using an incremental technique. These forty five teeth were randomly divided into three experimental groups (Group A, B and C) (n = 15). The teeth in Group A did not undergo any further procedures. The teeth in Group B and C were reinforced with composite impregnated glass fibre and polyethylene fibre, respectively. Fracture resistance was measured in Newtons (N). RESULTS: The positive controls showed the highest mean fracture resistance (811.90 N), followed by Group B (600.49N), Group A (516.96N) and Group C (514.64N), respectively. One Way analysis of variance (ANOVA) test revealed a statistically significant difference between all the groups (P = 0.001). Post-hoc Tukey test revealed a moderately significant difference (P = 0.034) between Control and Group B, and a strongly significant difference between Control and Group A (P = 0.002), and Control and Group C (P = 0.001). CONCLUSIONS: Endodontic therapy and MOD cavity preparation significantly reduced the fracture resistance of endodontically treated maxillary premolars (P = 0.001). No statistically significant difference was found between the experimental groups (Group A, B and C) (P > 0.1). However, the fracture resistance of the composite impregnated glass fibre reinforced group was much higher than the others.

An in vitro evaluation of fracture strength of endodontically treated teeth with simulated flared root canals restored with different post and core systems.

PURPOSE: The objective of this study is to evaluate the fracture strength and mode of failure of endodontically treated teeth with flared canals restored with two fiber reinforced systems (glass fiber and quartz fiber) and one base metal cast post and core system. MATERIALS AND METHODS: Forty five anterior teeth were decoronated at cemento-enamel junction and were endodontically treated. Post space was prepared and randomly divided into three groups according to post system. Specimens were loaded at 45° in a universal testing machine at a cross head speed of 0.5 mm/min until failure. The mode of failure was classified as repairable or non-repairable. RESULTS: Teeth restored with cast posts have fracture strength twice that of teeth restored with fiber posts. Fiber-reinforced posts failed at a certain compressive force but they were repairable unlike the non-repairable fracture seen with cast posts. CONCLUSION: The results of this study showed that, fracture strength and mode of failure in anterior teeth with flared canals varied according to the type of post used to support a crown.

Caries-risk assessment with a chairside optical spectroscopic sensor by monitoring bacterial-mediated acidogenic-profile of saliva in children.

OBJECTIVE: This study aimed to evaluate the ability of an optical spectroscopic sensor (OSS) to monitor bacterial-mediated acidogenic-profile of saliva resulting from bacteria-sucrose interaction. MATERIALS AND METHODS: Stage-1, characterization experiments were conducted to standardize the OSS. Stage-2 clinical experiments were carried out on stimulated saliva samples from 70 children of age-group 1-12 years. The bacterial-mediated acidogenic-profile of saliva mixed with sucrose was monitored using the OSS for 180 minutes. RESULTS: The clinical patients were categorized based on the dmfs score as caries-active, caries-inactive and caries-free. The bacterial-mediated acidogenic-profile measured in terms of t1/2 monitored using the OSS was significantly different between the caries-free and caries-active (P<0.05); and caries-free and caries-inactive groups (P<0.005). CONCLUSIONS: The significant correlation of the acidogenic-profile determined using the OSS and the caries-status highlighted the OSS as a sensitive and rapid chairside tool for the quantification of the acidogenic-profile of saliva that could help in monitoring the caries-risk in children.

An in vitro comparison of adhesive techniques and rotary instrumentation on shear bond strength of nanocomposite with simulated pulpal pressure.

AIM: The aim of this study is to evaluate the shear bond strength of composite to tooth using different adhesive techniques and rotary instruments under simulated pulpal pressure. MATERIALS AND METHODS: Sixty extracted human molars were randomly divided into two groups of 30 samples each (group I and II), according to the adhesive technique followed (i.e. total etch and self etch groups). Each group was further divided into two sub-groups (Sub-groups A and B) of 15 samples each according to the cutting instrument (diamond abrasive or carbide burs) used. Class II cavities were made with diamond abrasive or carbide burs, and restored with nano-composite under positive intra-pulpal pressure. Shear bond strength of the specimens were recorded simultaneously. RESULTS: After statistical evaluation using two-way ANOVA and t-test, the mean shear bond strength values of the groups are as follows: Group IA- 4.69 MPa, Group IB-6.15 MPa, Group IIA-4.3 MPa, and Group IIB-6.24 MPa. It was seen that group IIB showed highest bond strength followed by group IB. Group II A showed the least bond strength. CONCLUSIONS: Within the limitations of the study, diamond abrasive gave better bond strength than carbide bur with both the adhesive techniques.

Comparison of 2% chlorhexidine and 5.25% sodium hypochlorite irrigating solutions on postoperative pain: a randomized clinical trial.

AIM: To compare the levels of postoperative pain after cleaning and shaping of root canals using two different root canal irrigants for debridement. MATERIALS AND METHODS: Forty patients with irreversible pulpitis, pulp necrosis and non-vital teeth exhibiting acute apical periodontitis requiring root canal treatment were included. At random, canals were cleaned and shaped with the following protocols. 2% chlorhexidine solution in group I and 5.25% sodium hypochlorite solution in group II were used as an irrigants. Access cavities were closed with a sterile cotton pellet and cavit. The patients recorded degree of pain at various time intervals after cleaning and shaping on a visual analogue scale for 1 week. RESULTS: The mean pain score for group I was between 0.65 and 3.35 and for group II was between 0.95 and 4.50. There was significant difference in the pain level between the two groups only at 6 th hour postoperatively (P<0.05) and the pain was more in sodium hypochlorite group. CONCLUSIONS: More pain was present in teeth irrigated using 5.25% sodium hypochlorite when compared to that in teeth irrigated using 2% chlorhexidine solution. Significant difference in pain level was present only at 6th hour postoperatively, and at all other periods (24 th hour, 4 th and 7 th days) there was no significant difference in pain level between the two groups.