Intrasulcular injection of hydrogel CHA incorporated aPRF can locally reduce orthodontic relapse in rabbits.

Objective The study aimed to determine the effect of carbonate apatite (CHA) hydrogel-aPRF on osteoblastogenesis during relapse in rabbits. Materials and Methods Forty-five rabbits were divided into three groups (n = 15): the control, CHA, and CHA-autologous platelet-rich fibrin (aPRF) groups. An open-coil spring was compressed between brackets to distalize the lower incisors of the rabbits by delivering a force of 50 cN for 1 week. The new position of the teeth was retained for 14 days, and CHA hydrogel-aPRF was injected every 7 days. The appliances were then debonded to allow relapse. On days 0, 3, 7, 14, and 21 after debonding, transforming growth factor (TGF)-β1 and bone morphogenetic protein (BMP)-2 expression was examined using immunohistochemistry staining and Runx-2 levels were analyzed by enzyme-linked immunosorbent assay. The data collected were analyzed using analysis of variance and a post hoc Tukey’s test (p < 0.05). Results Histomorphometric analysis revealed that TGF-β1 expression in the CHA-aPRF group is statistically higher than that in other groups on days 0, 3, and 7 after debonding (p < 0.05). BMP-2 expression in the CHA-aPRF group was also statistically higher than that in the other groups on days 3, 14, and 21 after debonding (p < 0.05). ELISA showed that Runx-2 levels are slightly higher in the CHA-aPRF group than in the other groups (p > 0.05). Conclusion Although injection of CHA-aPRF aids in osteoblastogenesis associated with enhancing TGF-β1 and BMP-2 expressions, it does not significantly upregulate Runx-2 levels.

Objective The aim of this study was to analyze the effect of grape seed extract containing cyanidin on osteoclastogenesis (by means of receptor activator of nuclear factor-κ B ligand [RANKL] and osteoprotegerin [OPG] levels) and the number of osteoclasts during orthodontic relapse in Wistar rats. Materials and Methods This study is an in vivo quasi experimental research. A total of 32 male Wistar rats were used in the study, which were randomly split equally into two groups, grape seed (GS) and control group (CG). All rats were given an orthodontic force of 35 cN using a stainless steel 3-spin coil spring that was activated for 7 days and then conditioned to be passive. During this phase, the GS group was administered grape seed extract containing cyanidin once per day. Orthodontic appliances were removed from both groups afterward, and then the alveolar bone tissue was isolated consecutively according to observation days (days 1, 3, 7, and 14), while OPG and RANKL levels were analyzed in their gingival crevicular fluid using a specific enzyme-linked immunosorbent assay (ELISA). Tissues were then stained with hematoxylin–eosin (H&E) and observed under a light microscope to count the number of osteoclast cells. Data were analyzed statistically using an independent t-test (p < 0.05). Results The number of osteoclasts in the GS group was significantly lower than that in the CG group on all experiment days (p = 0.021; p = 0.001; p = 0.024; p = 0.001; p < 0.05). ELISA results showed that the RANKL level of the GS group was significantly lower on days 3 and 7 (p = 0.025; p = 0.039; p < 0.05), while the OPG level was significantly higher on days 1 and 3 in the GS group than in the CG group (p = 0.039; p = 0.021; p < 0.05). Conclusion Grape seed extract can prevent postorthodontic relapse movement by inhibiting osteoclastogenesis and reducing the number of osteoclasts in Wistar rats.

Relapse is considered a significant failure after orthodontic treatment. In response to relapse, RANKL expressions will increase, while OPG expressions will decrease. CHA is thought to be one of an ideal candidate for enhancing bone formation. Moreover, a-PRF is a source high levels of growth factors that play a central role in the bone remodeling. This research was intended to investigate the effect of hydrogel CHA-aPRF in preventing relapse. Hydrogel-CHA was initially designed, with its degradation profile and FTIR (Fourie’s Transform Infrared) spectra were investigated as the basis to find out optimum formulation before incorporated with aPRF. Hydrogel-CHA microspheres were prepared in 3 different compositions: those were encoded 30-CHA, 40-CHA, and 50-CHA. After the hydrogel formulation and characterization were completed, 10 mL blood samples were collected, then centrifuged at 1500 rpm for 14 min. At the end of the centrifugation process, the aPRF clot was isolated and then pressed to obtain their releasate. The releasate aPRF was then loaded into the best formulation candidate of hydrogel CHA. The hydrogel incorporated aPRF was then gently injected on the mesial side of incisor gingival sulcus of the rabbit after orthodontic tooth movement. The FTIR analysis showed that carbonated apatite was successfully developed during the fabrication process of hydrogel-CHA microspheres. It was also known that degradation profile of 30-CHA was considered ideal compared to the other compositions. The application of CHA-aPRF (group C) was proven to significantly prevent relapse, indicated by lowest percentage of relapse 21 days after debonding (29.95±3.91%) compared to control group. Furthermore, it has been found that expressions of RANKL were significantly lowest (p<0.05) in group C on day 0, 3, and 7, while OPG expressions showed significantly highest (p<0.05) in group C on day 14 and 21 after debonding. These results indicate that incorporation of hydrogel-CHA has potential effect to enhance alveolar bone remodeling and prevent orthodontic relapse by stimulates OPG expression and suppresses RANKL expression.

Background: A smile constitutes a form of measurement as to whether or not an orthodontic treatment has proved successful. A smile is said to be ideal if a balance exists between the shape of the face and teeth. One benchmark used to assess the quality of an ideal smile is that of buccal corridors. These are formed of the black space between the lateral edge of maxillary posterior teeth and the corner of the lip which appears during the action of smiling. Evaluating the contrasting perceptions of male and female smiles based on buccal corridor aspects is considered important to identifying the specific qualities an ideal smile. Purpose: The purpose of this study was to determine the difference between the perceptions of an ideal smile held by Indonesian dental students of both genders based on buccal corridors. Methods: A total of 36 dental students, equally divided between male and female students and ranging in age from 18-21 years old, were enrolled in this study. The smiles of all subjects were photographed from the front for later assessment by the subjects themselves. Assessment was undertaken twice, with a two-week interval between the first and second, by comparing subjects’ photographs with reference pictures of buccal corridors. Data gathered were analyzed by using kappa-statistic and U-Mann Whitney. Results: The results indicated that all the subjects showed a good level of coincidence in their analysis (κ=0.76). Statistical analysis showed that the score of 0.123 (p>0.05) was shown in U-Mann Whitney. Conclusion: Indonesian male and female dental students have the same perception of an aesthetic smile with regard to its buccal corridor.