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It is well known that the initiating factor for the biologic changes is the stress induced in the periodontal tissue; but as of now there is no gauge to measure the stress in the PDL directly. Therefore finite element model can be used to study the stress-strain relation through simulation of the PDL. The aim of the study was to simulate the stress response in the periodontium for different moment to farce ratios induced by tipping, translation, rotation, intrusion, extrusion and root torque by means of finite element method. The three-dimensional finite element model of the mandibular first molar was constructed. The pattern of Von misses stress and the maximum displacement of the mandibular molar was recorded on application of different combination of moment to force ratio. The periodontium was sensitive to changes in the load values. The stress pattern in the periodontal ligament for a lingually directed force without counterbalancing moments showed high concentration at the cervical level of the root. With addition of counter-tipping and counter-rotation moments, a relatively even distribution of stress throughout PDL was obtained. Additionally, high stress concentration was observed on the root surface at the furcation level for forces applied parallel to the long axis. Translation type of tooth movement showed relatively even distribution of the stress in the PDL and makes the tooth less susceptible to root resorption.

Objective: Work related musculo skeletal disorders (WMSD) are very common among dental practitioners who useprecise hand-wrist motions and prolonged static postures. The aim of this study was to develop an educative ergonomicplan and test its effectiveness in reducing symptoms of musculo-skeletal disorders among dental practitioners.Material and Methods: This study was conducted on a random sample of 50 dental practitioners of both genders(25 male, 25 female) practising for more than 4 years in urban Bengaluru, India and showing symptoms of neckpain, back pain or wrist pain. In the first round of the questionnaire data was collected from all 50 dentists. Nextan educative ergonomic plan was developed which included simple exercises and recommendations in the form ofdo’s and don’ts. The study population were asked to follow the guidelines given and perform the exercises givenin the poster daily for a period of 3 months. Then, the questions were again asked. The differences in responsesduring the first stage and second stage were analyzed. Results: The use of the ergonomic plan led to a statisticallysignificant improvement in certain ergonomic practises such as practise of changing their positions during clinicalpractice, keeping shoulders and arm at correct level while working and keeping instruments within hand reach.There was a statistically significant reduction in pain levels after the use of the ergonomic plan. Conclusion: Theergonomic plan in the form of recommendations and exercises were an effective tool in improving ergonomicpractises and reducing the symptoms of musculoskeletal disorders among dental practitioners.KEYWORDSErgonomics; Musculoskeletal disorders; Wrist pain; Back pain; Neck pain.

Aim: Temporomandibular disorders (TMD) are one of the main causes of non-dental orofacial pain. It has been reported that TMD occurred more frequently among individuals in stressful situations and that university students are more likely to have a high risk of anxiety related disorders. This study aims to assess the prevalence and severity of TMD in undiagnosed population consisting of students of different faculties in a university campus in Bengaluru using the Fonseca’s questionnaire.Material and Methods: Descriptive cross-sectional study conducted at a University Campus, Bengaluru. Completed forms of Fonseca’s questionnaire were collected from the sample consisted of 300 students. The questionnaire had two main parts. First part collected demographic information and past relevant histories. Second part had Fonseca’s 10 questions. The TMD severity was categorized as no TMD (0-15), mild TMD (20-40), moderate TMD (45-65) and severe TMD (70-100).Results: 33.3% on the sample showed varying signs of TMD. There was no statistically significant differences found between the TMD and non TMD groups with respect to age and sex. But when comparing varying grades of TMD there was a statistically highly significant difference seen in relation to age of the subjects.Conclusions:A high prevalence of TMD was found in the university students with majority of the cases having milder signs of TMD.

The aim of this finite element method (FEM) study was to assess the safety of 125-150 Hz vibrational frequency electric toothbrush on teeth and associated structures.A three-dimensional (3D) geometric model of entire skull having maxilla, mandible, and their dentitions was created using a computed tomography (CT) image of a healthy male patient. Linear static analysis was carried out by applying 15 g of force on anterior part of maxilla and mandible from labial and lingual sides each to calculate the primary displacement (sagittal, vertical, and transversal) and principal stress levels generated on the maxillary and mandibular dentition, on the maxilla and mandible and on the whole skull.A force of 15 g applied to maxillary anterior teeth from labial side caused a mean deflection of 0.003 mm and stress of 0.004 MPa on the teeth and supporting structures. A force of 15 g applied to maxillary anterior teeth from palatal side caused a mean deflection of 0.017 mm and stress of 0.017 MPa on the teeth and supporting structures. A force of 15 g applied to mandibular anterior teeth from labial side caused a mean deflection of 0.078 mm and stress of 0.051 MPa on the teeth and supporting structures. A force of 15 g applied to mandibular anterior teeth from lingual side caused a mean deflection of 0.077 mm and stress of 0.051 MPa on the teeth and supporting structures.For the applied loads and boundary conditions, very small or negligible amount of stresses were observed in maxilla, mandible, and their dentitions. The vibrational frequency of 150 Hz producing 15 g of force did not produce any harmful effects on maxilla, mandible, and their dentitions. Hence, 125-150 Hz of vibrational frequency can be considered optimum.An electric toothbrush using the vibration of 125-150 Hz produces negligible stress on teeth and associated structures.

Introduction: Micro-osteoperforation (MOP) and Low Level Laser Therapy (LLLT) are rapidly gaining popularity in clinical practice due their proven success in accelerating tooth movement and acceptable patient compliance. However, literature shows an inconsistent and variable evidence of their iatrogenic effects on the root and pulp due to biological variations of the samples chosen by the previously studies. Aim: To evaluate and compare the rate of tooth movement, changes in amount of external root resorption and pulp vitality in teeth during en masse anterior retraction associated with MOP and LLLT using split mouth technique. Materials and Methods: This was a double blinded, single center split mouth randomised clinical trial conducted at Faculty of Dental Sciences, MS Ramaiah University of Applied Sciences, Bangalore, Karnataka, India from March 2019 to October 2019. Total of 11 patients with bimaxillary dentoalveolar protrusion which required all four first premolar extractions were included in the study. Nickel Titanium (NiTi) closed coil springs were used for en masse retraction in upper and lower arches with force of 150g per side. Root resorption of all anterior teeth was evaluated using Cone Beam Computed Tomography systems (CBCT) and pulp vitality was checked using cold test after 4 months. The data was entered in Microsoft excel and the Statistical Package for Social Sciences software (SPSS) version 18.5 (SPSS Inc, Chicago) software was used for data entry and statistical analysis. A p-value of less than 0.05 was considered as statistically significant. Results: Total of 11 patients in which 9 were females and 2 males aged between 18-30 years with mean age 19±4.21 year, participated in this trial. LLLT (4 mm) and MOP (4.05 mm) showed similar performance in acceleration of tooth compared to each other. The overall root resorption was more in the experimental groups (LLLT- 2.60 mm, MOP- 2.84 mm) compared to the allotted controls. However, the canine showed less root resorption in both the experimental groups compared to the control. The overall root resorption was similar in both the experimental groups. The canine in LLLT group (0.30 mm) showed less root resorption compared to canine in MOP group (0.59 mm). There was no change in the pulp vitality status in both the experimental groups and the control groups. Conclusion: The overall root resorption in a given quadrant increases with increased rate of tooth movement. The tooth which was subjected to acceleratory orthodontic technique showed less root resorption compared to control. The tooth subjected to LLLT showed less root resorption as compared to the tooth subjected to MOP.

Introduction: Knowledge of transverse dentofacial dimensions is crucial for accurate diagnosis and treatment planning. Periodontitis can alter the widths of the arches by causing pathological migration of teeth and the concurrent bone loss can affect the transverse width of the arches. Aim: To compare the transverse dentofacial widths in adults with skeletal class I and class II malocclusions with horizontal growth pattern and with mild to moderate periodontitis using Cone Beam Computed Tomography (CBCT). Materials and Methods: This retrospective observational study was conducted in Department of Orthodontics, Faculty of Dental Sciences, Ramaiah University of Applied Sciences, Bengaluru, Karnataka, India, from January 2019 to January 2021. Total 96 CBCT samples (48 skeletal Class I, 48 skeletal Class II) of patients between age group of 25-35 years, patients having mild to moderate periodontitis based on bone loss seen on CBCT and patients having a horizontal growth pattern with the angle between sella-nasion and mandibular plane less than 320 degrees were included in the study. Transverse dentofacial measurements were made on the coronal plane of the CBCT scans. Data were analysed using Statistical Package for Social Sciences (SPSS) version 20. Chi-square test and Student’s t-test were used to compare age, linear measurements and angular measurements between the skeletal class I and skeletal Class II groups. A p-value of

Introduction: In adult patients seeking orthodontic treatment, some common reasons include unesthetic appearance and functional impairment such as difficulty in speaking or breathing. Thus, malocclusion and orthodontic care have become a Quality of Life (QoL) issue. Aim: To investigate the oral health-related quality of life in adults before and after orthodontic treatment. Materials and Methods: This quasi-experimental study was conducted in Faculty of Dental Sciences, M.S. Ramaiah University of Applied Sciences, Bangalore, India over a 2 year period from December 2014 to October 2016. Finally, 34 patients were included in the study. Longitudinal data which included OHRQoL(Oral Health-Related Quality of Life) and study casts for assessing the outcome by the Peer Assessment Rating (PAR) index was collected from two periods: (i) pretreatment data (T1), and (ii) post-treatment data (T2) collected 1 month after fixed orthodontic appliance debonding. Pretreatment and post-treatment Oral Health Impact Profile (OHIP-14) and PAR scores were compared using Paired t-test. Correlations between occlusal indices (PAR) and OHRQoL (OHIP-14) were determined by Spearman’s rank correlation coefficient. Results: Total of 42 patients were included in the study, out of which 34 patients responded to the questionnaire in which 11 were males and 23 females in the age range 18-30 years. From pre to postorthodontic treatment mean OHIP-14 summary score had significantly improved (score reduced) from 30.3 to 16.0. Similarly, mean PAR scores had reduced from 17.62 to 3.44. Significant correlation (p-value

Background. Although there are various intraoral and extraoral appliances for anchorage management in orthodontics, most fail to preserve the anchorage efficiently. Thus, there is a need for an appliance that can preserve anchorage in the sagittal, vertical, and transverse directions with good patience compliance and cost-effectiveness. This study compared the efficacy of butterfly arch and transpalatal arch (TPA) as an anchorage reinforcing unit during orthodontic space closure using a linear finite element model. Methods. A 3D model of the maxilla and associated structures was developed from CT images of an individual’s skull at a slice thickness of 1 mm. The magnitude of movements of anchor teeth in vertical, horizontal, and transverse directions was calculated in first premolar extraction cases during anterior retraction using a linear finite element model analysis and compared in two situations―butterfly arch and TPA attached to maxillary first molar for anchorage. Results. The anterior teeth had similar movements in the case of TPA and butterfly arch. There was more mesial and lingual movement in the first molars with TPA than in the butterfly arch, which had buccal but no mesial movement. The anterior teeth showed extrusion and the second premolars showed intrusion with TPA. Also, the von Mises stress and maximum principal stress were maximum with TPA at the cervical region of anterior and posterior teeth compared to the butterfly arch, where both stresses were uniformly distributed all over the teeth. Conclusion. A butterfly arch with its unique design, configuration, and biomechanical properties can be used as a device that can maintain the posterior anchorage efficiently

Resume Objectif Le traitement orthodontique tend a ameliorer l’apparence esthetique ; par consequent, connaitre quelles en sont les caracteristiques significatives est un objectif important en orthodontie. Cette etude visait a evaluer dans trois categories, profanes, dentistes et orthodontistes, la part de l’esthetique dentaire versus celle de la face dans le jugement esthetique. Materiel et methode Cette etude utilisait des photographies du sourire de face de huit volontaires (4 hommes et 4 femmes), âges de 16 a 24 ans. Il a ete demande a 150 evaluateurs (50 profanes, 50 dentistes et 50 orthodontistes) de selectionner quel visage etait le plus seduisant, celui aux traits esthetiquement agreables mais avec un sourire presentant une malocclusion evidente et celui aux traits ordinaires mais avec un sourire esthetique. La methodologie utilisee reposait sur un questionnaire. Resultats On observe une difference statistiquement significative de perception des visages entre les differents groupes d’evaluateurs. Un encombrement ou un diasteme interincisif figurent parmi les defauts ayant le plus d’impact sur la perception de l’attractivite d’un visage pour les profanes, plus qu’un sourire gingival ou des corridors labiaux sombres. Conclusion L’attrait du visage reste plus important que l’esthetique dentaire, dans les cas de malocclusion discrete.

Introduction: Application of orthodontic forces to a tooth is characterised by extensive macroscopic and microscopic changes during remodelling which occurs in the Periodontal Ligament (PDL), alveolar bone and gingiva. This occurs mainly due to the local stresses and strains subjected on the supporting tissues. As direct measurement of these parameters is almost impossible, Finite Element Method (FEM) is an effective method for calculating stress and strain distribution on the alveolar bone. Aim: To assess the stress and strain distribution in the cortical and cancellous bone around maxillary central incisors during the process of diastema closure with a constant force using FEM. Materials and Methods: A three-dimensional computer model of anterior segment of the maxilla simulated from a CBCT scan was reproduced using MIMICS software and they had varying width of midline diastema of 4 mm, 3 mm and 2 mm. Each tooth was designed with a bracket on the labial surface and a 0.019×0.025 orthodontic stainless steel wire. A 1.5 N of force was applied on the labial surface of the brackets. Stresses and strains around the two central incisors on the alveolar bone were calculated. Results: In the cortical bone, maximum compressive stress (Von-Mises stress) was concentrated at the mesial side and tensile stress (principle stress) on the distal side near the cervical region of the central incisors in all the 3 models. Maximum stress was seen in the 2mm midline diastema model. In the cancellous bone, both these stresses were concentrated along the roots of central incisor cavity more towards the middle of the tooth in all the 3 models. In the longitudinal section, stress and strain was more concentrated at the cervical region gradually decreasing as they reached apex of the tooth in cortical bone and in the cancellous bone maximum stress was observed in the middle third. Conclusion: Stresses in the cortical bone increases when the diastema gap is small while strain in cancellous bone increases when the midline diastema width is large. The stresses in cancellous bone remain constant in all the 3 models. Graphically the strains were more concentrated near cervical region of the teeth in both the cortical and in cancellous bone maximum stress was observed in the middle third.

Torque control of individual incisors using pre-adjusted edgewise (PAE) appliance is a common clinical challenge. In order to overcome the inherent disadvantages of the PAE appliance in efficiency of torque delivery, the use of light wire auxiliaries for early control of the roots of the instanding tooth in the alignment stage itself has been described using the case report. A case of an 18-year-old female patient with the chief complaint of irregularly placed upper front teeth has been described. Treatment was carried out by extraction of four premolars and the resolution of crowding and the incorporation of light wire auxiliaries with PAE appliance has been described. For the alignment of 42 which was lingually displaced, and to bring it into the arch by bodily displacement rather than labial tipping, a LIght wire auxiliary (Mollenhauer aligning auxiliary) was used in conjunction with PAE appliance. The biomechanical advantages of the procedure have been highlighted. The use of light wire auxiliaries have definite advantages and hence should be a part of our armamentarium to handle such cases. Light wire auxiliaries offer us a biomechanically superior and economical alternative to apply torque forces on incisors.

Objective: The aim of the study was to analyze the displacement and stress pattern in periodontal ligament (PDL) of palatally impacted canines (PIC) lateral incisors (LI) and first premolars (FP) adjacent to the impacted teeth when different magnitudes of orthodontic extrusion forces were applied along with variation in the inclination of the impacted teeth. Methodology: A three-dimensional finite element model of a maxilla containing a palatally impacted canine was made with three different inclinations of the palatally impacted canine (model one, model two, and model three). Forces of 50, 70, and 100 g were loaded on the impacted tooth. Results: There was steady increase in the initial rate of displacement in the three teeth when the magnitude of the force that was applied on to the PIC increased. The initial rate of displacement was more in the FP tooth as compared to LI and the impacted teeth. The von Mises stress on the PDL varied along with the variation in the inclination of the impacted canine. Conclusion: The study showed that there was variation in the displacement and the stress distribution in the impacted canine when it was placed in different angulations. The rate of displacement of the impacted teeth reduced when the crown of the palatally impacted canines (PIC) was inclined more mesial. The use of minimal forces is ideal to extrude the impacted canines as observed from the study that the PDL stress increases with increase in the magnitude of force.

Conventionally the use of surgical assisted tooth movement is to hasten orthodontic tooth movement. In this article, a case of 13 year-old male with oligodontia has been described in whom piezocision has been used to improve bone turnover and remodeling in long standing edentulous spaces which have less medullary bone and more cortical bone.

OBJECTIVE: To determine the prevalence of malocclusion and orthodontic treatment need in a sample of Omani adolescents aged 11–16 years. MATERIALS AND METHODS: The total sample included 854 adolescents with 387 boys and 467 girls between the age of 11 and 16 years with no previous orthodontic treatment history. The study design was cross-sectional. The parameters studied were skeletal relationship, lip competency, teeth impactions, missing teeth, contact point displacement, crowding, spacing, incisors and molars classification, overjet, overbite, crossbite, oral hygiene and caries. The Index of Orthodontic Treatment Need (IOTN) was used to study the need for orthodontic treatment for the total sample. RESULTS: There was a high prevalence of Class I jaw relationship (86.2%). About 81.6% of the sample studied had Class I molar relationship and 73.8% had Class I incisors relationship. About 61.4% of the sample had no contact displacement, while 5.2% had contact displacement >4 mm. Severe crowding in the maxilla was found in 2.3% while spacing was found in 24.2%. Around 11% of the sample studied had Class II div 1 incisors relationship, 13.5% Class III and only 1.8% had Class II div 2 incisors relationship. Only 8.6% of the sample studied had an overjet >6 mm while 16.3% had a deep bite and 0.2% had anterior open bite of >4 mm. Teeth impaction was found in 11.7% while permanent missing teeth was present in 1.8%. The results showed that 13.9% had a very great need for treatment while 43.2% of the sample did not need any treatment. CONCLUSION: Among the Omani adolescents, there was a high prevalence of Class I jaw relations and Class I molar relationship. The prevalence of malocclusion and treatment need in Omanis shows some variation when compared to other ethnicities.

The direct bonding of a fixed wire retainer often poses clinical difficulties. While there are several possible techniques, the present paper describes a simple method employing a ball clasp (S handle) to assist in the stabilisation of the wire to be attached. The advantages and disadvantages are indicated.

Diabetes mellitus (DM) is a chronic disorder of carbohydrate, fat and protein metabolism. The prevalence of DM is growing rapidly worldwide and is reaching epidemic proportions. Traditionally, orthodontic treatment was considered to be a treatment modality for healthy young people. However, with increasing patient awareness the trend has changed with adults now seeking orthodontic treatment. Approximately, half of the patients with diabetes are undiagnosed and a dental examination may provide the first indication of the disease, and therefore a clinician must have a basic knowledge of the oral manifestations of DM. This article briefly deals with the medical aspects of DM, its oral manifestations and orthodontic treatment considerations.

Objective: To evaluate the ratio of the condylar axis and corpus axis of the mandible in subjects with different growth pattern and sagittal skeletal relation. To assess if the above ratio is similar to the golden ratio in all the groups of patients. Materials and Methods: pretreatment lateral cephalograms of adult patients were analyzed and six groups were selected with 30 patients in each group. (male: 15, female: 15). The characteristics of each group were: Group 1 - patients with average growth pattern, Group 2 - horizontal growth pattern, Group 3 - vertical growth pattern, Group 4 - class-I skeletal bases, Group 5 - class-II skeletal bases, and Group 6 - class-III skeletal bases. The cephalograms were traced manually and the ratio between condylar and corpus axis was calculated using Golden ratio software ( http://www.markuswelz.de/software2/index.html ). The mean ratio for each group was calculated and this ratio was compared with the golden ratio (0.6180) using sample t test. P value was set at 0.05. Results: No statistically significant difference ( P > 0.05) was found between the mean value of the ratio of condylar to corpus axis of the mandibles and the golden ratio in all groups except the vertical growth pattern group ( P Conclusion: In the sample studied, the ratio of condylar axis to corpus axis in all groups closely matches the golden ratio except in the vertical growth pattern patients where the ratio was significantly reduced (0.6151).