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BackgroundThe study aimed to evaluate and compare the stress distribution and 3-dimensional displacements along the craniofacial sutures in between the Rapid maxillary Expansion (RME) and Implant supported RME (I-RME).MethodsFinite element model of the skull and the implants were created using ANSYS software. The finite element model thus built composed of 537692 elements and 115694 nodes in RME model & 543078 elements and 117948 nodes with implants model. The forces were applied on the palatal surface of the posterior teeth to cause 5mm of transverse displacement on either side of the palatal halves, making it a total of 10mm. The stresses and the displacement values were obtained and interpreted.ResultsVarying pattern of stress and the displacements with both positive and negative values were seen. The maximum displacement was seen in the case of plain RME model and that too at Pterygomaxillary suture and Mid-palatal suture in descending order. In the case of I-RME maximum displacement was seen at Zygomaticomaxillary suture followed by Pterygomaxillary suture. The displacements produced in all the three planes of space for the plain RME model were greater in comparison to the Implant Supported RME model. And the stresses remained high for all the sutures in case of an I-RME.ConclusionsThere is a definite difference in the stress and the displacement pattern produced by RME and I-RME model and each can be used according to the need of the patient. The stresses generated in case of conventional RME were considerably less than that of the I-RME for all the sutures.

Engineering has not only developed in the field of medicine but has also become quite established in the field of dentistry, especially Orthodontics. Finite element analysis (FEA) is a computational procedure to calculate the stress in an element, which performs a model solution. This structural analysis allows the determination of stress resulting from external force, pressure, thermal change, and other factors. This method is extremely useful for indicating mechanical aspects of biomaterials and human tissues that can hardly be measured in vivo. The results obtained can then be studied using visualization software within the finite element method (FEM) to view a variety of parameters, and to fully identify implications of the analysis. This is a review to show the applications of FEM in Orthodontics. It is extremely important to verify what the purpose of the study is in order to correctly apply FEM.

Objective:To investigate the influence of silver (Ag), zinc oxide (ZnO), and titanium dioxide (TiO2) nanoparticles on shear bond strength (SBS).Materials and Methods:One hundred and twenty extracted premolars divided into four groups with thirty specimens in each group. Group 1 (control): brackets (American Orthodontics) were bonded with Transbond XT primer. Groups 2, 3, and 4: brackets (American Orthodontics) were bonded with adhesives incorporated with Ag, ZnO, and TiO2 nanoparticles in the concentration of 1.0% nanoparticles of Ag, 1.0% TiO2, and 1.0% ZnO weight/weight, respectively. An Instron universal testing machine AGS-10k NG (SHIMADZU) was used to measure the SBS. The data were analyzed by SPSS software and then, the normal distribution of the data was confirmed by Kolmogorov–Smirnov test. One-way ANOVA test and Tukey's multiple post hoc procedures were used to compare between groups. In all statistical tests, the significance level was set at 5% (P < 0.05).Results:A significant difference was observed between control (mean [standard deviation (SD)] 9.43 [3.03], confidence interval [CI]: 8.30–10.56), Ag (mean [SD]: 7.55 [1.29], CI: 7.07–8.03), ZnO (mean [SD]: 6.50 [1.15], CI: 6.07–6.93), and TiO2 (mean [SD]: 6.33 [1.51], CI: 5.77–0.89) with SBS (F = 16.8453, P < 0.05) at 5% level of significance.Conclusion:Incorporation of various nanoparticles into adhesive materials in minimal amounts may decrease SBS and may lead to the failure of bracket or adhesive. The limitation of this study is that it is an in vitro research and these results may not be comparable to what the expected bond strengths observed in vivo. Further clinical studies are needed to evaluate biological effects of adding such amounts of nanoparticles and approve such adhesives as clinically sustainable.

Context: Periodontally accelerated osteogenic orthodontics (PAOO) combines alveolar corticotomy, bone graft materials, and the application of orthodontic forces for rapid correction of malocclusions. Aims: The present study aims to primarily assess differences in orthodontic treatment duration, bone quality around corticotomy sites, postoperative healing, and subjective pain when corticotomy was done conventionally and with the placement of recombinant human bone morphogenetic protein-2 (rhBMP-2). Settings and Design: Thirty individuals participated in this study. Individuals were randomly assigned into each of the following experimental groups; C + BMP: Corticotomy with 0.5 μg/mL rhBMP-2 and C: Corticotomy only. Materials and Methods: Clinical parameters included recording the duration of the treatment period, visual analog scale scores and early wound healing index scores. The evaluation of bone density was performed at baseline, 3 months, and 6 months by using RVG. Statistical Analysis Used: Two-way analysis of variance and post hoc multiple comparison tests were used to compare data between test and control groups at different time points. Results: rhBMP-2 application was effective in reducing the overall treatment time and resulted in an increase in bone density around corticotomy sites at the end of the treatment period when compared to conventional corticotomy procedure. Placement of rhBMP-2 neither delayed wound healing nor affected participant pain scores. Conclusions: From this trial conducted over a period of 6 months, rhBMP-2 has the potential to function as a regenerative material in PAOO.