Context: Lower degree of conversion (DC%) of monomer to polymer in a resin composite restoration could be a health hazard for the patient as well as it could affect the longevity of the restoration. Aims: This study is aimed to compare and evaluate the DC% of four different composites polymerized using ultrafast photopolymerization. Settings and Design: In-vitro study. Materials and Methods: A total of 40 disc-shaped composite samples were used in the study. Twenty samples were prepared for each group using 2 mm height and 6 mm diameter Tygon tube as a matrix. All of the composites were cured using the Woodpecker i Led light-curing unit with an intensity of 2300–2500 mW/cm 2 (TURBO mode). Samples in Group 1 were cured for 1 s and samples in Group 2 were cured for 3 s. Each group had 4 subgroups of five samples of the 4 resin composites tested. After photo-activation, the specimens were stored under dark dry conditions at room temperature for 24 h before testing. The DC% was measured using Fourier-transform infrared spectroscopy. Statistical Analysis Used: The DC% were analyzed using ANOVA, and Tukey HSD post hoc test using IBM SPSS 21 software. Results: Among the experimental groups, Group 2 showed a higher DC% which ranges from 93.7% to 95.4% than Group 1 which ranges from 58.5% to 65.5%. There was a statistically significant difference in the DC% among the materials tested ( P < 0.05). Conclusions: Within the limitations of the study, it was concluded that composites cured for 3 s showed a higher DC% which ranges from 93.7% to 95.4% than those cured for 1 s. The DC% also varied among the four different composites tested.

Introduction:Comparing ante-mortem and post-mortem dental data is a principal method of identification in forensic odontology. Radiographic images of amalgam have been used in dental forensics for identification due to their unique appearance.Aim:The aim of this study was to investigate whether radio-opaque composite restorations have a potential for identification in forensic odontology.Materials and Methods:Thirty typodont mandibular first molar teeth were prepared with Class-II (proximo-occlusal) cavities and restored with a radio-opaque composite (Tetric N-Ceram). Two sets of standardized radiographs were taken from the 30 teeth, keeping the radiological parameters constant. One set of these 30 radiographs was named as SET 1. Ten randomly chosen radiographs from the other set and two other radiographs of Class-II composite restorations in typodont teeth constituted SET 2. Thirty dentally trained examiners were asked to match the 12 radiographic images of SET 2 with those of SET 1.Results:The results show that 15 examiners were able to correctly match all the 12 images. Statistical analysis was done using kappa statistical test.Conclusion:This study shows that, if the post-mortem radiographs are accurate duplicates of ante-mortem radiographs of composite restorations, then the shape of the composite restoration is unique and can be used for identification.

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Aim: The aim of the study was to evaluate the shear bond strength of composite to dentin with 2 different dentin bonding agents after dry dentin is rewetted with a desensitizer. Materials and Methods: Sixty human mandibular molars were taken and the occlusal surface was ground to expose flat dentinal surface.  The samples were divided into two major groups Group I and Group II based on the bonding agent used. In Group I Gluma Bond5 was used and in Group II Adper Single Bond 2 was used.  Each major group is subdivided into three subgroups a, b and c with ten samples each.  Sub Group ‘a’ is moist dentin group. Sub Group ‘b’ is dry dentin group, Sub Group ‘c’ is rewetted dentin group. The desensitizer used is GLUMA Desensitizer. All these samples were thermocycled and the shear bond test was performed using Instron Universal Testing Machine. Results: Dry dentin rewetted with GLUMA Desensitizer followed by GLUMA Bond5 showed highest shear bond strength than that of other subgroups. The data was analysed using ANOVA and Tukeys honestly significant test. Conclusion: Desensitizer used as a rewetting agent increases the shear bond strength of composite on dry dentin. Keywords: Glutaraldehyde, rewetting.

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