Calcitonin and vitamin D3 have high therapeutic potential for improving diabetic mandibular growth

The goal of this study was to assess the effect of the intermittent combination of an antiresorptive agent （calcitonin） and an anabolic agent （vitamin D3） on treating the detrimental effects of Type 1 diabetes mellitus （DM） on mandibular bone formation and growth. Forty 3-week-old male Wistar rats were divided into four groups： the control group （normal rats）, the control C＋D group （normal rats injected with calcitonin and vitamin D3）, the diabetic C＋D group （diabetic rats injected with calcitonin and vitamin D3） and the diabetic group （uncontrolled diabetic rats）. An experimental DM condition was induced in the male Wistar rats in the diabetic and diabetic C＋ D groups using a single dose of 60 mg.kg-1 body weight of streptozotocin. Calcitonin and vitamin D3 were simultaneously injected in the rats of the control C＋D and diabetic C＋D groups. All rats were killed after 4 weeks, and the right mandibles were evaluated by micro-computed tomography and histomorphometric analysis. Diabetic rats showed a significant deterioration in bone quality and bone formation （diabetic group）. By contrast, with the injection of calcitonin and vitamin D3, both bone parameters and bone formation significantly improved （diabetic C＋ D group） （P 〈 0.05）. These findings suggest that these two hormones might potentially improve various bone properties.

Evaluation of Micro Leakage of Two Direct Esthetic Restorations with Different Preparation Techniques

Objectives: In recent times, the term “minimal intervention dentistry” has coined to describe a new approach to the treatment of the disease of caries. This study was carried out to evaluate the marginal integrity of class V cavity in permanent posterior teeth prepared with different air abrasion parameters compared with classical rotary cavity preparation. Methods: A total number of 150 sound caries for free human posterior teeth were used in this study. Teeth were extracted for periodontal disease or orthodontic reasons and the average age of patients between 20 - 35 years. Teeth were divided according to the type of restoration into two main groups: Group I (n = 75) restored with low shrinkable posterior composite (P90) and Group II (n = 75) restored with Ketac nano ionomer (N100). Each main group was divided into five groups (n = 15), then each group was further subdivided into three subgroups (n = 5) according to the storage time (immediately, three months, and six months). All teeth would be tested at both occlusal and gingival margins of prepared class V cavity according to the method of cavity preparation. Results: A high significant difference was found in the mean ranks of micro-leakageat both occlusal enamel and gingival dentin walls among Groups 1 - 5 (p-value of Conclusion: Low shrinkable silorane based composite yielded better results of micro-leakage scores along the occlusal enamel and gingival dentin walls when the cavity of class V was prepared with air abrasion technique with large size alumina particles under high pressure at immediate storage time as compared with Ketac N100.

Comparison of resin composite restorations microleakage: An <i>in-vitro</i>study

The aim of this study was to compare the microleakage of total-etch and self-etch adhesives by three methods including dye extraction, dye penetration and fluid filtration with determining the correlation value among these techniques. Seventy-two premolar teeth were selected for this in vitro study and Class 5 cavities were prepared on the buccal surface of these at the cementoenamel junction area. It was applied for half of these cavities, Optibond Solo Plus (OSP) (two-step etch & rinse) and another half, Optibond All-in-One (OA) (one-step self-etch) and then all of them were restored with a light cure resin composite;Herculite XRV. Then samples were divided randomly into three subgroups based on the method of microleakage measurement (n = 12). In the first pair group, leakage was assessed by the dye extraction method. Dye penetration and fluid filtration methods were used in the second and third pair groups for the same purpose respectively. Data were analyzed by Paired t-test and Wilcoxon test and correlation coefficients (α = 0.05). There was no significant difference in the dye extraction (P = 0.657) and dye penetration (P = 0.732) methods between the microleakage of total-etch and self-etch adhesives. Microleakage of self-etch adhesive in fluid filtration technique was significantly more than total-etch adhesive (P = 0.012). No significant correlation was found among the results obtained with the three methods of microleakage evaluation. Adhesive systems showed variously behave in different methods of microleakage assessment.