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Background: Age estimation is important not only in identifying dead body of a person but also in living persons since there is an increasing rate of juvenile delinquencies recorded every year. To avoid foul play by age fabrication, legal age estimation becomes important. Facial growth alteration takes place in the jawbones as age advances which can be observed with lateral cephalometry. Thus, the aim of the study is to create a regression formula for age estimation using cephalometrics of teenagers in Salem population. Materials and Methods: A cross-sectional study was done using 770 lateral cephalometrics of teenagers (13-19 yrs) in Salem population. Nine cephalometric points with two linear hard tissue measurements (condylion to mandibular plane (AFH) and palatal plane to menton (PFH)) and one angular soft tissue measurement (z angle) were recorded as predictor variables using a digital lateral cephalometric software (Carestream CS8100 SC) which were subjected to regression analysis using SPSS version 21.0 to develop a formula for age estimation. Results: Significant association on age was obtained for the two linear measurements. The regression formula generated for estimating the age was Age = 7.146 + 0.044 (AFH) + 0.146 (PFH) with R2 value = 0.674. Conclusion: Within the limitations of the present study, age estimation of teenagers in Salem population can be estimated. The predictability of the age can be increased by taking more cephalometric variables in generating the formula with increase in sample size.
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INTRODUCTION: Three-dimensional finite elemental analysis (FEA) is a contemporary research instrument for the numeric simulation of a real physical system's mechanical process. FEA can be used as a very effective tool to analyze and compare various aspects of rapid palatal expanders and to determine the stress distribution in maxillofacial bones and displacement and the biomechanical effects it has on the circummaxillary sutures. This study evaluates the effects of different modes of rapid palatal expansion on maxillary protraction as a treatment modality in skeletal Class III malocclusion by determining the stress and displacement along the circummaxillary sutures using the FEA. MATERIALS AND METHODS: Initially, a three-dimensional finite element simulation of the maxillofacial skeleton and sutures was obtained by Mimics software (Leuven, Belgium) from the cone-beam computed tomography (Dentsply Sirona, USA) images of a 30-year-old adult with normal occlusion. A geometrical preparation of the three expansion appliances, (A) hybrid MARPE (miniscrew-assisted rapid palatal expander) appliance (Fav anchor, India), (B) tooth-borne HYRAX (hygenic rapid expander) appliance (Welcare orthodontics, Kerela), and (C) bone-borne modified MARPE appliance (Biomaterials, Korea), was transferred to ANSYS WORKBENCH, 2020 R1 software (ANSYS, Inc., USA), and three finite element models with each appliance were prepared. A protraction force of 500g was applied to the occlusal plane that is directed 20 degrees inferiorly. The tensile stress, compressive stress, and the amount of displacement on the circummaxillary sutures were assessed and compared in all the three appliances. Young's modulus (kg/mm2) and Poisson's ratio (V) were used to calculate the stress and displacement in sutures adjacent to the maxilla in different aspects. RESULTS: On analyzing the stress distribution, the tensile stress was found to be maximum in the medial aspect of the frontomaxillary suture of the bone-borne modified MARPE appliance (C), and the minimum tensile stress was found in the lateral aspect of the sphenozygomatic suture in hybrid MARPE (A). Again, the compressive stress distribution was found to be maximum in the medial aspect of the frontomaxillary suture in all three simulations and the minimum compressive stress in the superior aspect of the internasal suture in hybrid MARPE (A) along with the frontonasal suture at its medial aspect for tooth-borne HYRAX (B) and bone-borne modified MARPE (C). Displacement of the maxilla in all the planes was observed to be the largest for the bone-borne modified MARPE (C) appliance. On the contrary, the minimum displacement was found in the tooth-borne HYRAX (B) appliance. Conclusion: The findings reveal that all three modes of rapid palatal expanders produced stress and displacement along the circummaxillary sutures on the application of protraction force with bone-borne modified MARPE being more effective in treating posterior crossbites thereby correcting the skeletal Class III malocclusions successfully.
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Introduction: The novel COVID-19 which spread's primarily through oral and nasal passage poses a major threat of spread during dental treatments. It is important for dental practitioners to use minimal aerosol techniques. The aim of this study is to compare the time taken, efficiency and aerosol generated between modified and conventional technique (CT) of bracket bonding. Methods: This study includes 40 patients who required complete orthodontic treatment. In all 40 patients, one of the arches was bonded with modified technique (MT) and the opposing with CT. The time taken to prepare tooth in both the techniques were accessed. The efficiency of bond was seen over a period of 6 months. The amount of aerosol particulate matter generated during CT and MT was observed using a laser air quality monitor. Conclusion: There is no significant difference in the bond failure and time taken between both the techniques. The aerosol generated in MT was minimal or almost negligible when compared to the use of CT.
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BACKGROUND: Extraction in orthodontics are carried out in the cases where there is space deficiency to align the teeth. The elective extraction of first or second premolars has been discussed in the literature for more than 50 years. In the 1940s and 1950s Nance, Dewel and Carey reviewed this as a useful option, and in the 1970s Logan and other leading orthodontists favoured the extraction as choice. It is not always the elective extraction of premolar is a smooth drive for the surgeon as well as to patient. Sometimes the elective extraction of premolar result in complications, which might be due to both anatomical and surgical factors. METHODOLOGY: The study sample consisted of 100 patients referred for one or more orthodontic extractions to the department of oral and maxillofacial surgery were included in this retrospective study at the vivekanandha dental college for women tiruchengode between November 2014 and May 2016. All referrals were from the department of orthodontics. A survey was carried out to record the intraoperative risks and correlated with its morbidity as when occured. All intraoperative morbities were managed appropriately as required. RESULT AND CONCLUSION: Between November 2014 and May 2016, 100 patients had one or more premolar teeth removed by the oral surgeons. The sample size was 100 patients who had a total of 334 premolars removed. The sample's mean age was 11.4+\- 8.4 years, and 57.0% were male. The average number of teeth extracted per patient was 2.34 +\- 1.46, and 73.8% had complete root development. More than 93.4% of subjects had normal root and bone morphology, whereas 35.65% had variations in root forms and bone texture. The intra-operative and post operative complication rates were 7.4% and 1.9%, respectively. Complications were generally minor (91.9%) and were managed nonoperatively on an outpatient basis. There were no case of oral antral communication.
