How to cite this article: Rivis O, Potapchuk A, Goncharuk-Khomyn M, Bokoch A. Use of mini-implant anchorage for second molar mesialization: comprehensive approach for treatment efficiency analysis. Pesqui Bras Odontopediatria Clín Integr. 2020; 20:e5262. https://doi. AbstractObjective: To approbate the complex approach for assessment of second molar mesialization outcomes with the use of orthodontic mini-implants. Material and Methods: The sample consisted of 62 patients, divided into study (n=32) and control group (n=30). Mesialization procedure in the study group was conducted with the use of braces system and orthodontic mini-implants as additional anchorage devices, while in control group mesialization was provided only with the use of the brace system. Dynamic registration of bone level changes and the entire range of tooth movement were carried out on digital orthopantomograms obtained with the use of Planmeca ProMax 2D. Results: Findings of orthopantomographic (OPG) analysis have shown that cases of second molar mesialization with the use of mini-implants as temporary anchorage characterized with more stable conditions of bone levels around displaced teeth compare to cases, where mesialization was provided only with the use of braces systems without any additional anchorage. The terms of treatment in the study group with the use of dental mini-implants as the anchorage was reduced by 8.8 ± 0.12 months compared to the control group (p<0.05). Conclusion: The use of orthodontic miniimplants as anchorage constructions during the mesialization of the mandibular second molars contributes to the reduction of treatment duration and support the more prognostic movement of teeth, that does not provoke significant pathological changes in the levels of the surrounded alveolar ridge and minimize the risk of associated periodontal complication occurrence.

The health of the oral cavity is an important component of the overall physical, mental and social well- being of each person. It is known that untimely detection and treatment of patients with dentoalveolar anomalies can lead not only to social maladaptation of this category of people but also to an increase in the risk of developing a carious process, periodontal diseases, as well as dysfunction of the temporomandibular joint. The presence of a dentoalveolar anomaly in a child can lead to a social disadvantage of patients among peers, as well as loss of active career growth in young and mature age. The incidence rate may vary considerably depending not only on the country of research but also on its region, as well as sex and age of the studied categories of people. The patients' parents specify the type and duration of feeding, the presence of such bad habits as sucking fingers, lips, or the tongue, respiratory features (sleeping with an open mouth), whether a child was followed up by otolaryngologist or neurologist for adenoids, sinusitis, rhinitis, as well as other diseases that can negatively affect the development of the patient's chewing apparatus. In an objective examination, attention was paid to the disturbance of nasal breathing, visually evaluated the amplitude and TMJ movement range. With an increase in age in the examined children there was a de- crease in the prevalence of deep bite, while the frequency of detecting mesial, open bite, as well as the dis- placement of dental arches from the middle line, increased. Rotated teeth, as well as disturbance of interdental gaps was detected more frequently with age while diastems were detected less frequently. The sharp decrease in the frequency of dental anomalies is observed in the transition from the II period of a variable bite (11-13 years) to the period of a constant bite (14-17 years). The study showed that regular check-ups are the most effective methods for identifying patients with tooth anomalies in schoolchildren and can significantly reduce the number of patients who need this type of treatment with an adequate orthodontic care management. The purpose of the study is to analyze the prevalence of dentoalveolar anomalies in schoolchildren of Uzhgorod. Material and methods. The study involved 339 schoolchildren in Uzhgorod. An analysis of the prevalence of dentoalveolar anomalies was carried out in three age groups: the first period of the mixed bite (6–9 years), the second period of the mixed bite (10–13 years), and the permanent bite (14–17 years). Results. It has been shown that dentoalveolar anomalies occur in the majority (78.6%) of school-age children. The most common anomalies of the teeth position (47.1%) and anomalies are the ratios of dental arches (37.3%). Anomalies in the size of the jaws (11.5%) and dentoalveolar anomalies of functional origin (4.1%) occur less often. However, 70.4% of all dentoalveolar anomalies are combined. Dentofacial anomalies were observed in children aged 10 to 13 years (II period of a shifting bite) more often. A sharp decrease in the frequency of dentoalveolar anomalies is observed during the transition from the II period of a mixed bite (11-13 years) to the I period (14-17 years) of a permanent bite. Conclusion. The study showed that medical examinations and preventive examinations are the most effective methods for identifying patients with dentoalveolar anomalies in schoolchildren and, with the adequate orthodontic care management, can significantly reduce the number of patients requiring this type of treatment.

The aim of the study. Conduct a digital analysis of the distribution of relative force occlusal load in the area of the second permanent mandibular molars before and after their mesialization. Research methods. In order to evaluate the distribution of inter-occlusal force load in the process of mesialization of molars on the mandible, two clinical study groups were formed. The first group consisted of 32 persons (18 women / 56.25% and 14 men / 43.75%) aged from 18 to 25 years, who had orthodontic treatment using braces and mini-implants. The second group included 30 people (19 women / 63.33% and 11 men / 36.67%), orthodontic treatment was performed using a brace system without additional intraosseous support on the mini-implants. T-scan apparatus investigated the distribution of relative force occlusal load in the area of the second permanent mandibular molars before and after orthodontic intervention. Results of the study. The use of the T-scan apparatus is an accurate and informative tool for analyzing the distribution of functional occlusal force load within the dentition. During the analysis of the parameters of the chewing load in the area of the second permanent molars on the mandible before orthodontic treatment, an increase of this index was found in almost all patients of both study groups. In the first group in 4 (12.5%) persons the maximum relative occlusive force load in the area of the second permanent molars on the mandible was 10–20%, which is the range of the norm; in 15 (46.9%) cases this indicator was 20–30. %, in 10 (31.2%) patients had 30-40%, and in 3 (9.4%) exceeded 40%. In the second group, the parameters of the relative force occlusal load in the area of the second permanent molar on the mandible were as follows: in 5 (16.7%) persons in the range of 10-20%, in 13 (43.3%) persons - 20-30%, in 10 (33.3%) patients - 30-40% and in 2 (6.7%) patients more than 40%. After treatment, normalization of the relative occlusal force load was observed in the area of the second permanent molars on the lower jaw in the majority of patients of both study groups. In particular, in the first group in 21 (65.6%) persons the parameters of occlusal load were in the range of 10–20%, in 11 (34.4%) persons were 20–30%. In the second study group, 17 (56.7) patients observed parameters of the occlusal load on the second molar in the range of 10-20%, in 12 (40%) persons - 20-30% and in one (3.3%) patient 30-40%. In addition, moving molars involves changing the usual occlusal ratios associated with the non-identity factor in the shape and size of the first and second molars. At the same time, occlusal contacts on all other teeth are altered due to their alignment with the orthodontic equipment and the appearance of new contact points that did not interact before the start of treatment. Conclusions. The analysis of the distribution of the relative occlusal load in the area of the second permanent molars on the lower jaw with the help of T-scan after orthodontic treatment revealed the normalization of this indicator in the majority of patients in both study groups. Specifically, in the first group, 21 (65.6%) subjects had parameters of relative occlusal load within the range of 10–20%, and in 11 (34.4%) individuals were 20–30%. In the second study group, 17 (56.7%) patients were in the range of 10–20%, 12 (40%) patients - 20–30% and one (3.3%) patients 30–40%. The data obtained in both the first and second study groups indicate the need to perform procedures of grinding after orthodontic intervention to achieve appropriate occlusive normalization, the volume of which in each clinical situation is determined individually under the control of the T-scan apparatus.

The aim: To substantiate the need for a combination of interdisciplinary approaches to diagnosis, treatment and correction of dento-maxillofacial anomalies of teenagers based on the analysis of the need for orthodontic treatment using the DAI, IOTN, ICON aesthetic indices. Materials and methods: Empirical, epidemiological, clinical, analytical-synthetic, sociological, psychological research methods, questionnaires, dental indexeshave been used in various combinations. Results: As a result of a clinical examination of 2,260 teenagers (1,096 boys and 1,124 girls), 1,474 individuals have been bselected for orthodontic treatment with the following degree of complexity: mild – in 25 examined (35.71±4.95%), moderate – in 31 individuals (44.28± 5.48%), heavy – 14 (20.00±3.11%). After an in-depth dental examination and determination of the psychological profile, 70 teenagers have been selected for treatment. Conclusions: The effectiveness of the use of dental indices as a screening tool to eliminate the discrepancy between objective medical indicators of the level of need for correction of dento-maxillofacial anomalies and the level of expected results in adolescents has been proven.

The aim of the study. Carry out a comparative analysis of the support ability of human jaw bone tissue in monocortical and bicortical installation of a mini-implant of own design OMG. Research methods. In order to study biomechanical characteristics of developed OMG mini-implant and bone tissue capacity during monocortical and bicortical installation, the finite element method (MSE) was used. The scheme and finite element 2-D model of bicortical installation of OMG mini-implant (length 8 mm, diameter 1.8 mm) provided full penetration through one layer of cortical bone equal to 1 mm, the entire cancellous bone and immersion in the second layer of cortical bone by 0, 5 mm. No implantation was immersed in the second cortical layer of bone during monocortical installation. A single force load of 1 N was applied in the horizontal direction parallel to the cortical plate of the bone. Results of the study. One of the most important factors leading to the success of the use of a mini-implant is its stability in the process of orthodontic treatment. Quite a high level of failure in the monocortical installation of mini-screws has led to the search for better methods to ensure the stability of their use. This was a bicortical method of fixation, based on the placement of the minig screw in the thickness of the two cortical plates of the jaws. Area for such installation of mini-screws can be a site of a palate and alveolar sprouts at installation of miniimplants through all its thickness. As shown by our data on the use of the finite element method under the force load of the biomechanical system "bone - mini-implant", the stress concentration zone is located in the area of the cortical bone of the jaw. The results of the calculation of the maximum stresses (σmax, MPa) and the maximum possible displacements (umax, mm) of the mini-implant in the biomechanical system "bone - mini-implant" in monocortical installation were, respectively, 8.27 MPa and 0.300 * 10-8 mm and in bicortical installation 6.00 MPa and 0.201 * 10-8 mm. The bicortical method of fixing the mini-implant in the jaw bones significantly increases the ability to resist deformation of this type of biomechanical system under force loads of the mini-implant. In the bicortical method of mini-implant placement, the extreme values of equivalent according to Mises stresses in the upper part of the cortical bone of the jaw are reduced by 27%. This can be explained by a significant increase in the area of contact due to the two layers of the cortical bone of the jaw with the surface of the mini-implant. Conclusion. The bicortical method of installing mini-implants is a more effective and reliable way to provide skeletal support during orthodontic treatment.