Construction of Customized Palatal Orthodontic Devices on Skeletal Anchorage Using Biomechanical Modeling

Orthodontic implants have been developed for the implementation of skeletal anchorage and are effectively used in the design of individual orthodontic devices. However, despite a significant amount of clinical research, the biomechanical aspects of the use of skeletal anchorage have not been adequately studied. The aim of this work was to numerically investigate the stress–strain state of the developed palatal orthodontic device supported by mini-implants. Four possible options for the placement of mini-implants in the bone were analyzed. The effect of a chewing load of 100 N on the bite plane was investigated. The study was carried out using biomechanical modeling based on the finite element method. The installation of the palatal orthodontic device fixed on mini-implants with an individual bite plane positioned on was simulated. The dependence of equivalent stresses and deformation changes on the number and location of the supporting mini-implants of the palatal orthodontic device was investigated. Two materials (titanium alloy and stainless steel) of the palatal orthodontic device were also investigated. The choice of a successful treatment option was based on the developed biomechanical criteria for assessing the surgical treatment success. Application of the criteria made it possible to estimate the stability and strength of fixation of each of the considered mini-implants installation options. As a result, options for the mini-implants optimal placement were identified (the first and the fourth which provide distributed front and side support of the device), as well as the preferred material (titanium alloy) for the manufacture of the palatal orthodontic device.

Use of domestic light-cured polymer at production of removable orthodontic devices

The purpose of work was the clinical laboratory research, identification of reaction of local immunity mucous a mouth, indicators of globulins fraction on carrying within 6 months of the removable orthodontic device from domestic light-cured polymer at children. Immunoglobulins of three classes IgM, IgG, IGA and calculated values of sIgA and sc (free secretory component) were investigated. Contents sekretorny IgA (sIgA) and a free secretory component (sc) is especially important. Results were estimated by V.V. Zverev’s technique et al. (2011) [6]. Results showed that immunoglobulins changed individually at each patient within one extent of dysbiotic disorders that is connected with an initial situation of a condition of oropharynx of the child which had no considerable fluctuations within one degree of a condition of a microbiota of a mucous oropharynx of the child. The bioinertness of Nolatek photopolymer in the form of basic material of the orthodontic device is established. Light-cured domestic nanostructural polymer has high quality of the operational properties in children’s practice of clinic of orthodontics conforming to modern requirements for bioinertness, an esthetics and functionality.

Presurgical Alignment of Bilateral Cleft Segments With 3D Simulation Under Special Consideration of the Vomer: A Technical Note

Background: The main goal of presurgical orthopedics (PSO) for patients with bilateral cleft lip and palate is to correct the protruded and/or twisted premaxilla. However, PSO is associated with the risk of uncontrolled development of the vomer, which has received little attention to date. Solution: We present a removable orthodontic device that can be used to keep or align the vomer and the premaxilla in the midline during preoperative molding of cleft segments independently and 3 dimensionally.

The effect of rotation upon dental structure components following orthodontic fix appliance

Background and aims. The purpose of the study is to evaluate through a FEM (Finite Element Method) the effects of the rotation movement upon a complex structure (enamel– pulp -alveolar bone, PDL), for external load. Method. The progressive action of a fixed orthodontic device on three teeth: first molar, first and second premolar is modeled and simulated with the components placed on the buccal and palatal surfaces of the tooth. For the reproduction of a situation similar to the real one, the loading of the model was performed through a nodal force applied at a height of the crown, of various amplitudes, F = 1 N; 2, 3 and 4 N. The values of stress are: maximum stress of the whole structure and the shearing effect for the pulp. Results. The characteristics of the material are Young’s E modulus and Poisson’s ratio of the components of the modeled structure. The most stressed elements of the structure are the pulp and the ligament, revealed by von Mises stress. The elements of the structure are mainly stressed in fiber compression in the direction of the moment’s action given by the orthodontic forces and in fiber stretching in the opposite direction. Out of the orthodontic movements: translation, tipping, intrusion-extrusion , rotation is the most dangerous. Conclusions. The accumulated stress effect in the pulp becomes dangerous. The orthodontic movements given by dental force values higher than 1.5-2N are to be avoided.

Gambaran Kesehatan Gingivitis Pengguna Alat Ortodontik Yang Memasang Pada Tukang Gigi

ABSTRAK Perawatan gigi ditentukan oleh kesehatan gingival. Rendahnya pemeliharaan kesehatan gigi dan mulut akan mempengaruhi kesehatan jaringan periodontal. Pemakaian Alat ortodontik berhubungan dengan peningkatan kejadian gingiva dan perdarahan. Penelitian ini bertujuan untuk menggambarkan gingiva pengguna alat ortodontik yang memasang pada tukang gigi swasta. Jenis penelitian ialah deskriptif dengan desain cross sectional. Penelitian dilakukan di salah satu praktek tukang gigi swasta dan rumah. Responden penelitian berjumlah 40 orang. Teknik pengambilan sampel ialah total sampling. Analisis data secara deskriptif dan dijabarkan dalam bentuk narasi. Hasil penelitian menunjukkan pengguna alat ortondontik yaitu perempuan sebanyak 29 orang ( 72,5%), dan laki-laki sebanyak 11 orang (27,5%). Kejadian gingivitas berdasarkan umur paling banyak pada usia 7-12 tahun sebanyak 9 orang (27,5%) dan 13 – 18 sebanyak 14 orang (43,75%). Kejadian gingivitis berdasarkan jenis kelamin, laki-laki sebanyak 10 orang (90,9%) dan perempuan sebanyak 22 orang (75,86%). Kata kunci ; , tukang gigi, gingivitis, gigi dan mulut ABSTRACT Orthodontic treatment is determined by gingival health. The low maintenance of oral health will affect the health of periodontal tissue. The use of orthodontic devices is associated with an increased incidence of gingiva and bleeding. This study aims to describe the gingivitis of orthodontic appliance users who install it on private dental artisans. This type of research is descriptive with a cross-sectional design. The study was conducted at one of the private and home dental practice. Research respondents numbered 40 people. The sampling technique is total sampling. Data analysis is descriptive and described in narrative form. The results showed orthodontic device users, namely 29 women (72.5%), and 11 men (27.5%). The incidence of gingivitis based on age at most at the age of 7-12 years was 9 people (27.5%) and 13-18 were 14 people (43.75%). The incidence of gingivitis based on sex, men as many as 10 people (90.9%) and women as many as 22 people (75.86%). Keywords; Orthodontics, dental artisan, gingivitis, teeth, and mouth

Minimally Invasive Adhesive Rehabilitation for a Patient With Tooth Erosion: Seven-year Follow-up

SUMMARY Tooth wear is a multifactorial condition of growing concern. In clinical practice, it is often a challenge for prevention and treatment since many etiological factors may be involved. This case report describes an esthetic rehabilitation of a young patient presenting tooth wear due to erosion. The etiological factor of this case was the patient sucking on lemons, an acidic fruit. The main complaint of the patient was the appearance of short maxillary incisors. The treatment involved orthodontic and restorative dentistry techniques. First of all, an orthodontic device was used to increase the vertical dimension of occlusion and create an adequate space for the direct restorations. The posterior teeth were restored with two direct composite resin techniques; the anterior teeth were then restored using a balanced occlusion. The seven-year follow-up of the case is presented. Replicas of the restorations were made and visualized under scanning electron microscopy up to the 12-month evaluation. In the clinical follow-up at seven years, maintenance of the results and restorations can be clearly seen.

Unwanted tooth movement produced by the bonded retention wire : the “wire syndrome,” observations, theories, clinical consequences : second part

Sometimes teeth can move even if they seem to have been perfectly stabilised by a retention wire. We call this phenomenon the “wire syndrome”. It has been well described both in the mandibular and maxillary arches in part one of this article. For the moment, there has been no mechanical explanation for this phenomenon in the scientific literature. After an analysis of photographic documents from fellow specialists and an examination of cases from our own office, we have developed a theory to explain the mechanical element involved. We will divide our analysis into two hypotheses. They could be inter-connected. The first so-called “intrinsic” hypothesis groups together procedural erreurs which all lead to the use of an active bonded wire. In such cases, the wire is directly responsible for the movements. Its action is the same as that of an orthodontic device directly bonded on the teeth. The second “extrinsic” hypothesis shows that a tooth with a well bonded wire can rotate if the link between the wire and the composite is broken and if force is present. The clinical evidence we have gathered could allow us to combat this phenomenon efficiently.

CRANIOFACIAL STRESS PATTERNS AND DISPLACEMENTS AFTER ACTIVATION OF HYRAX DEVICE: FINITE ELEMENT MODELLING

Rapid maxillary expansion is employed for the treatment of cross-bite and deficiency of transversal dimension of the maxilla in patients with and without cleft of palate and lip. For this procedure, generally, different orthodontic appliances and devices generating significant transversal forces are used. The aim of this study is the finite-element analysis of stresses and displacements of the skull without palate cleft and the skull with unilateral and bilateral cleft after activation of the Hyrax orthodontic device. Two different constructions of the orthodontic device Hyrax with different positions of the screw relative palate are considered. In the first case, the screw is in the occlusal horizontal plane, and in the other, the screw is located near the palate. Activation of the orthodontic device corresponds to the rotation of the screw on one-quarter turn. It is established that the screw position significantly affects the distributions of stresses in skull and displacements of the cranium without palate cleft and with unilateral or bilateral palate cleft. Stresses in the bone structures of the craniums without cleft and with cleft are transferred from the maxilla to the pterygoid plate and pharyngeal tubercle if the screw displaces from the occlusal plane to the palate. Depending on the construction of the orthodontic appliance, the maxilla halves in the transversal plane are unfolded or the whole skull is entirely rotated in the sagittal plane. The stresses patterns and displacements of the skull with bilateral palate cleft are almost unchanged after activation of the orthodontic devices with different positions of the screw, only magnitudes of stresses and displacements are changed. The obtained results can be used for design of orthodontic appliances with the Hyrax screw, as well as for planning of osteotomies during the surgical assistance of the rapid maxillary expansion.