Effectiveness of amine fluoride mouthwash in preventing white spot lesions during fixed orthodontic therapy - A randomized control trial.

Background and Aim: One of the main reasons that patients seek orthodontic treatment is aesthetics. Unfortunately, treatment with fixed orthodontic appliances can at times increase the chances of developing white spot lesions on the surfaces of teeth, thus creating a new aesthetic issue for the patient. The prevalence of white spot lesions (WSL) reported after treatment varies from 2% to 97%, and these lesions can occur despite increased attention to hygiene. Hence the aim of this study was to assess the effect of Amine fluoride mouthwash in preventing white spot lesions during fixed orthodontic therapy. Materials and Methods: Study participants were randomly divided into two groups (Group A - experimental 25 patients and Group B - control 25 patients). The pre-intervention and post-intervention intra-oral digital photographs were analysed by using ImageJ software to assess the percentage of the facial surface affected on the teeth (10 maxillary teeth), which had white spot lesions. Results: The mean value of WSLs showed significant difference between the experimental and control groups. Mean values of WSL in the experimental group decreased from 2 to 1.54 with a mean difference of 0.46 after 6 months of follow-up which indicated that amine fluoride mouthwash was effective in preventing WSLs during fixed orthodontic treatment. Conclusion: WSLs scores were significantly reduced in patients who received the mouthwash when compared to patients who followed standard oral hygiene regimen with fluoridated toothpaste only. In clinical practice, amine fluoride mouthwash is an effective method for the prevention of WSLs during fixed orthodontic treatment.

Comparison of the effectiveness of butterfly arch versus transpalatal arch in anchorage reinforcement: A linear 3D finite element study.

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.

Comparison of mandibular buccal shelf bone characteristics between two facial types using cone beam computed tomography.

Background: Mandibular buccal shelf (MBS) offers good quality and quantity of bone for orthodontic bone screw (OBS) insertion. Despite several reports of treated patients, there are numerous variables in selecting the exact placement site for OBS placement in the MBS. There are also anatomical variations in this area which must be considered. Objectives: This study aims to measure and compare the MBS bone characteristics for OBS placement using cone beam computed tomography (CBCT) between two different facial types. Materials and Methods: Eighty CBCT samples were collected (40 samples of group A horizontal growers and 40 of group B vertical growers). Each CBCT image was reconstructed and oriented with CS 3D CBCT software. The cortical bone thickness, the slope of the MBS, and buccolingual inclination of mandibular second molar were measured and analysed. Result: Cortical bone thickness among horizontal growers was 5.23 ± 0.58 mm and among vertical growers was 4.85 ± 0.37 mm. The slope of MBS among horizontal growers was 60.83 ± 6.15 degrees and among vertical growers was 66.75 ± 6.27 degrees. In both the parameters there was a statistically significant difference between the groups. There was no significant difference between the groups for the buccolingual inclination of 2nd molar. Conclusion: Increased cortical bone thickness and the flatter slope of MBS at the 2nd molar region allows for easier placement of OBS in horizontal growers than in vertical growers.

Effectiveness of an educative ergonomic plan in reducing musculo-skeletal disorders among dental practitioners / Efetividade de um plano ergonômico educativo na redução de distúrbios osteormusculares entre dentistas

Objective: Work related musculo skeletal disorders (WMSD) are very common among dental practitioners who use precise hand-wrist motions and prolonged static postures. The aim of this study was to develop an educative ergonomic plan 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 neck pain, back pain or wrist pain. In the first round of the questionnaire data was collected from all 50 dentists. Next an educative ergonomic plan was developed which included simple exercises and recommendations in the form of do's and don'ts. The study population were asked to follow the guidelines given and perform the exercises given in the poster daily for a period of 3 months. Then, the questions were again asked. The differences in responses during the first stage and second stage were analyzed. Results: The use of the ergonomic plan led to a statistically significant improvement in certain ergonomic practises such as practise of changing their positions during clinical practice, 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: The ergonomic plan in the form of recommendations and exercises were an effective tool in improving ergonomic practises and reducing the symptoms of musculoskeletal disorders among dental practitioners. (AU)

Objetivo: Distúrbios osteomusculares relacionados ao trabalho (DORT) são muito comuns entre os dentistas que usam movimentos precisos de mão e punho e posturas estáticas prolongadas. O objetivo deste estudo foi desenvolver um plano ergonômico educativo e testar sua eficácia na redução de sintomas de distúrbios osteomusculares em dentistas. Material e Métodos: Este estudo foi realizado em uma amostra aleatória de 50 dentistas de ambos os sexos (25 homens, 25 mulheres) trabalhando há mais de 4 anos na área urbana de Bengaluru, Índia e apresentando sintomas de dor no pescoço, dor nas costas ou dor no punho. Na primeira etapa do questionário foram coletados dados de todos os 50 dentistas. Em seguida, foi desenvolvido um plano ergonômico educativo que incluía exercícios simples e recomendações na forma de fazer e não fazer. Os participantes foram solicitados a seguir as orientações dadas e realizar os exercícios indicados no pôster diariamente por um período de 3 meses. Em seguida, as perguntas foram feitas novamente. Foram analisadas as diferenças nas respostas durante a primeira etapa e a segunda etapa. Resultados: A utilização do plano ergonômico levou a uma melhora estatisticamente significativa em algumas práticas ergonômicas, como a prática de mudar de posição durante o atendimento clínico, manter ombros e braços no nível correto durante o trabalho e manter os instrumentos ao alcance das mãos. Houve redução estatisticamente significativa dos níveis de dor após a utilização do plano ergonômico. Conclusão: O plano ergonômico na forma de recomendações e exercícios foi uma ferramenta eficaz na melhoria das práticas ergonômicas e na redução dos sintomas de distúrbios osteomusculares entre os cirurgiões-dentistas. (AU)

Analysis of stress in periodontium associated with orthodontic tooth movement: a three dimensional finite element analysis.

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.

Effect of 125-150 Hz Vibrational Frequency Electric Toothbrush on Teeth and Supporting Structures: A Finite Element Method Study.

AIM AND OBJECTIVE: 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. MATERIALS AND METHODS: 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. RESULTS: 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. CONCLUSION: 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. CLINICAL SIGNIFICANCE: An electric toothbrush using the vibration of 125-150 Hz produces negligible stress on teeth and associated structures.

Displacement and periodontal stress analysis on palatally impacted canine - A finite element analysis.

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.

The prevalence of malocclusion and orthodontic treatment need in Omani adolescent population.

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.

Comparison of the influence of dental and facial aesthetics in determining overall attractiveness.

OBJECTIVE: Orthodontic treatment aims at improving the perceived aesthetics; hence knowing which characteristics play a significant role in determining aesthetics is an important orthodontic objective. The aim of this study was to evaluate among laypersons, general dentists and orthodontists the importance of dental versus facial aesthetics. MATERIALS AND METHODS: Frontal face smile photographs of eight volunteers (4 males & 4 females), age group ranging from 16 to 24 years were used for the study. One hundred and fifty evaluators (50 - lay people, 50 general dentists and 50 orthodontists) were asked to select which face they found most attractive - an aesthetically pleasing face with a malocclusion evident in their smile or an average face with an aesthetic smile. A questionnaire method was followed. RESULTS: There was a statistical significant difference in the perception of the faces among the group of the evaluators. Crowding and midline diastema have more of an effect on the perception of attractiveness by laypersons than gumminess or increased buccal corridor space. CONCLUSION: Facial attractiveness is the dominating factor compared to dental aesthetics in cases where the malocclusion is less noticeable.

Surgically Assisted Orthodontics: Use of Piezocision in a Case of Oligodontia to Accelerate the Rate of Tooth Movement.

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.

A simple technique for the direct bonding of a lingual retainer: a clinical hint.

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.