Effect of piezoincision on the rate of mandibular molar mesialization: A randomised clinical trial.

Background and Aim: The aim of this clinic study was to investigate the effect of piezoincision on the rate of mandibular molar mesialization using clinical, radiological, and biochemical methods. Materials and Methods: Twenty-one patients requiring mandibular first molar extraction and second molar mesialization were included in the study which was designed as split-mouth study. Piezoincision was performed on the buccal surface of alveolar bone following regional alignment to the randomly selected side. 150 g of force was applied to the second molar teeth using mini-screw-supported anchorage after the piezoincision. Cone beam computed tomography (CBCT), gingival crevicular fluid (GCF) and digital model records of the patients were obtained. Two- and three-dimensional measurements were performed and compared on the CBCT images in a study which lasted 24 weeks. Results: According to the model analysis, the canine-second molar distance was consistently reduced and a greater decrease was measured on the experimental group (p < 0.05). Second molar mesial rotations increased in both groups (p < 0.001). Two-dimensional measurements on CBCT images showed increased mesial and buccal tipping of second molars in experimental group (p < 0.001). There was a significant increase in mesialization measurements of experimental group (p < 0.001). Three-dimensional measurements on the CBCT images showed a decrease of root length in both groups (p < 0.001), and a greater decrease was found in the experimental group (p < 0.001). When intra-group changes in GCF results were examined, it was observed that there was no significant change in osteoprotegerin (OPG) values over time in experimental group (p = 0.148). Conclusion: The piezoincision technique provided acceleration of mandibular molar mesialization and did not cause further damage to the buccal alveolar bone. Piezoincision can be used as a safe method in the mandibular molar region.

Effects of curcumin and melatonin on bone formation in orthopedically expanded suture in rats: A biochemical, histological and immunohistochemical study.

OBJECTS: To investigate the effects of curcumin (CUR) and melatonin (MEL) on new bone formation following rapid maxillary expansion (RME) in rats. SETTING AND SAMPLE POPULATION: For this study, 24 12-week-old adult male Wistar albino rats from the Animal Laboratory at Adnan Menderes University, Faculty of Medicine, were used. MATERIALS AND METHODS: The rats were randomly divided into the following 3 groups (n = 8 each): only expansion (OE), expansion plus MEL (MEL) and expansion plus CUR (CUR). CUR and MEL were given to the rats during the study period. After the sacrifice of the animals, biochemical, histological and immunohistochemical examinations were performed. RESULTS: Serum bone alkaline phosphatase levels in the MEL group were statistically (P = .007) higher than in the OE group. Serum glutathione peroxidase and catalase activities in the CUR and MEL groups were significantly higher than in the OE group (P = .007 and P = .021, respectively). Inflammatory cell infiltration, new bone formation and capillary intensity parameters did not demonstrate statistically significant differences between the groups (P = .865, P = .067 and P = .055, respectively). The immunohistochemical findings revealed that IL-1, IL-6 and TNF-α H scores showed considerable differences between the groups (all P < .001). The highest IL-1, IL-6 and TNF-α H scores were found in the OE groups rather than in the other groups (P < .001). CONCLUSION: CUR and MEL treatments may be effective in accelerating new bone formation and beneficial in preventing relapse following the RME procedures.

Evaluation of digital model accuracy and time-dependent deformation of alginate impressions.

OBJECTIVES: The aim of this study was to evaluate the accuracy of digital models produced with the three-dimensional dental scanner, and to test the dimensional stability of alginate impressions for durations of immediately (T0), 1 day (T1), and 2 days (T2). MATERIALS AND METHODS: A total of sixty impressions were taken from a master model with an alginate, and were poured into plaster models in three different storage periods. Twenty impressions were directly scanned (negative digital models), after which plaster models were poured and scanned (positive digital models) immediately. The remaining 40 impressions were poured after 1 and 2 days. In total, 9 points and 11 linear measurements were used to analyze the plaster models, and negative and positive digital models. Time-dependent deformation of the alginate impressions and the accuracy of the conventional plaster models and digital models were evaluated separately. RESULTS: Plaster models, negative and positive digital models showed significant differences in nearly all measurements at T (0), T (1), and T (2) times (P < 0.01, P < 0.05, and P < 0.001). Arch perimeter measurements did not differ at T (0) and T (1) times (P > 0.05), but they demonstrated statistically significant differences at T (2) time (P < 0.05) between the models. CONCLUSIONS: This study showed that measurements on negative digital models offer a high degree of validity when compared to measurements on positive digital models and plaster models; differences between the techniques are clinically acceptable. Direct scanning of the impressions is practicable method for orthodontists.