Academic literature on the topic 'Interceptive Orthodontics. Maxillary expansion. Hyrax'

A expansão rápida da maxila, ERM, é uma técnica interceptora utilizada na correção de problemas transversais do arco superior, já bastante estudada e difundida, a qual promove uma disjunção da sutura palatina mediana através de aparelhos ortopédicos como o Hyrax. Sua melhor indicação se dá em crianças em desenvolvimento, mais precisamente antes do término do pico de crescimento puberal, para tratar problemas resultantes de atresias maxilares, a qual é um estreitamento da arcada superior no sentido transversal, causando uma divergência em relação à mandíbula. As atresias maxilares podem resultar em mordidas cruzadas posteriores, apinhamentos dos dentes, falta de espaço no arco  para irrupção dos dentes decíduos, interferência na fonação, mastigação, respiração e comprometimento da estética do paciente. O Hyrax é um aparelho mais bem aceito por ser dentosuportado, portanto sem contato íntimo com a mucosa palatina, causando menos irritações na mucosa e de mais fácil higienização, cumprindo com sucesso sua função de corrigir as constrições maxilares. Portanto, este trabalho, apresenta um caso clínico de expansão rápida da maxila com o aparelho Hyrax, para correção de uma atresia maxilar de uma paciente de 9 anos e 2 meses de idade, que se encontrava no início do surto de crescimento puberal; tal tratamento proporcionou a expansão esperada, obtendo um ganho de espaço e um melhor contorno do arco superior, favorecendo assim uma melhor relação dos arcos dentários.

ABSTRACTObjective: To evaluate the anterior and posterior maxillary width, the nasal passage volume, the oropharyngeal minimum axial area, and volume changes in unilateral cleft lip and palate patients treated with one of the following four expanders: Hyrax, Fan-Type, inverted mini-hyrax supported on the first permanent molars (iMini-M), or inverted mini-hyrax supported on the first premolars (iMini-B).Materials and Methods: A total of 40 patients with transverse maxillary deficiency who were submitted for rapid maxillary expansion were divided in four groups according to type of expander used. Cone-beam computed tomography images were taken before and 3 months after expansion. One-way analysis of variance was used to analyze the differences among the groups, and paired t-tests were used to evaluate the changes in each group.Results: All groups showed a significant increase in the anterior maxillary width, with no intergroup differences. The iMini-B was the only group that did not show a significant increase in the posterior maxillary width. The intergroup comparison demonstrated differences among all groups except between Hyrax and iMini-M, which showed the greatest posterior expansions. The intragroup analysis showed a significant increase in the nasal passage volume in hyrax and inverted mini-hyrax on the molar groups, but the intergroup comparison revealed a significant difference only between Fan-Type and inverted mini-hyrax on the molars. None of the expanders caused significant changes in the oropharyngeal measurements.Conclusions: Only the Hyrax and inverted mini-hyrax on the molar expanders effectively increased the nasal passage volume, and none of the expanders evaluated in this study modified the oropharyngeal airway.

ABSTRACT Objective To investigate the efficacy of microimplant-assisted rapid palatal expansion (MARPE) to treat skeletal maxillary discrepancies during the post-pubertal growth spurt stage. Materials and Methods Sixty patients with skeletal maxillary transverse deficiency during the post-pubertal growth spurt stage were randomly divided into MARPE and Hyrax groups. Thirty patients (mean age: 15.1 ± 1.6 years) were treated using the four-point MARPE appliance; 30 patients (mean age, 14.8 ± 1.5 years) were treated using the Hyrax expander. Cone beam computed tomography scans and dental casts were obtained before and after expansion. The data were analyzed using paired t-tests and independent t-tests. Results The success rates of midpalatal suture separation were 100% and 86.7% for MARPE and Hyrax groups, respectively. Palatal expansion and skeletal to dental ratio at the first molar level were greater in the MARPE group (3.82 mm and 61.4%, respectively) than in the Hyrax group (2.20 mm and 32.3%, respectively) (P < .01). Reductions in buccal alveolar bone height and buccal tipping of the first molars were less in the MARPE group than in the Hyrax group (P < .01). Conclusions MARPE enabled more predictable and greater skeletal expansion, as well as less buccal tipping and alveolar height loss on anchorage teeth. Thus, MARPE is a better alternative for patients with skeletal maxillary deficiency during the post-pubertal growth spurt stage.

ABSTRACT Objectives To evaluate and compare the intensity of pain caused by rapid maxillary expansion (RME) with two expanders: Hyrax and Haas type, in growing patients. Materials and Methods Thirty-nine patients (23 girls and 16 boys) with an average age of 9.3 years (SD = 1.39 years) were randomized into two groups and treated with Hyrax- and Haas-type expanders. In both groups, initial activation of the expander screw was one full turn on the first day followed by 2/4 of a turn two times a day (morning and night) for 7 days. Inclusion criteria were patients presenting with a posterior crossbite or maxillary atresia between 7 and 12 years old. To evaluate the intensity of pain during the active phase of the treatment, a combination of the Numerical Rating Scale and Wong-Baker Faces Pain Scale was used. Mann-Whitney test was used to compare the two treatment groups. Results There was significant inverse correlation between days following insertion and pain. During the expansion period, 100% of the children reported some pain. Hyrax expander subjects reported greater pain than those treated with the Haas-type expander only on the first day. The level of pain remained greater in girls throughout treatment. Conclusions Pain was reported regardless of the type of expander and was higher in the Hyrax group only on the first day of activation.

Objective: The aim of the present study was to evaluate the transverse effect of rapid maxillary expansion in patients with unilateral complete cleft lip and palate while comparing the Haas and Hyrax appliances. Methods: The sample consisted of 48 patients divided into two groups: Group I - 25 patients treated with modified Haas appliance (mean age: 10 years 8 months); and Group II - 23 patients treated with Hyrax appliance (mean age: 10 years 6 months). Casts were taken during pre-expansion and after removal of the appliance at the end of the retention period. The models were scanned with the aid of the 3 Shape R700 3D scanner. Initial and final transverse distances were measured at cusp tips and cervical-palatal points of maxillary teeth by using the Ortho Analyzer(tm) 3D software. Results: The mean expansion obtained between cusp tips and cervical-palatal points for inter-canine width was 4.80 mm and 4.35 mm with the Haas appliance and 5.91 mm and 5.91 mm with the Hyrax appliance. As for first premolars or first deciduous molars, the values obtained were 6.46 mm and 5.90 mm in the Haas group and 7.11 mm and 6.65 mm in the Hyrax group. With regard to first molars, values were 6.11 mm and 5.24 mm in the Haas group and 7.55 mm and 6.31 mm in the Hyrax group. Conclusion: Rapid maxillary expansion significantly increased the transverse dimensions of the upper dental arch in patients with cleft palate, with no significant differences between the Hass and Hyrax expanders.

ABSTRACT Objectives To compare the effects of a hybrid miniscrew-supported expander versus a conventional Hyrax (CH) expander in growing patients. Materials and Methods Forty patients were randomized into two groups: a hybrid Hyrax (HH) expander group using a Hyrax expander with two miniscrews and a CH expander group. The final sample had 18 subjects (8 female, 10 male; initial age of 10.8 years) in the HH group and 14 subjects (6 female, 8 male; initial age of 11.4 years) in the CH group. Cone-beam computed tomography examinations and digital dental models were obtained before expansion and 11 months postexpansion. The primary outcomes included the orthopedic transverse effects of expansion. Intergroup comparison was performed using analysis of covariance (P < .05). Results Significantly greater increases in the nasal cavity width, maxillary width, and buccal alveolar crest width were found for the HH group. No intergroup differences were observed for dental arch width or shape changes. Conclusions The HH group showed greater increases in the nasal cavity width, maxillary width, and buccal alveolar crest width. No differences were observed for intermolar, interpremolar, or intercanine widths; arch length; or arch perimeter. Arch size and shape showed similar changes in both groups.

ABSTRACT Objective: To compare the dentoskeletal effects of rapid (RME) and slow (SME) maxillary expansion in patients with bilateral complete cleft lip and palate (BCLP). Materials and Methods: This was a secondary analysis of a previous randomized controlled trial (RCT). Forty-six patients (34 male, 12 female) with BCLP and posterior crossbite (mean age of 9.2 years) were randomly assigned to two study groups. Group RME comprised subjects treated with Haas/Hyrax expander. Group SME included patients treated with quad-helix appliance. Cone-beam computed tomography (CBCT) was performed before expansion (T1) and after appliance removal at the end of a 6-month retention period (T2) for a previous RCT that compared the transverse skeletal effects of RME and SME. CBCT-derived cephalometric images were generated and cephalometric analysis was performed using Dolphin Imaging Software (Chatsworth, Calif). Intergroup comparisons were performed using t tests (P < .05). Results: Baseline forms were similar between groups. No significant differences between RME and SME groups were found. Conclusions: Rapid and slow maxillary expansion produced similar sagittal and vertical changes in patients with BCLP. Both Haas/Hyrax and quad-helix appliances can be used in patients with vertical facial pattern. Clinical relevance: RME and SME can be equally indicated in the treatment of maxillary arch constriction in patients with BCLP.

ABSTRACT Objectives To evaluate the volume, amount, and localization of root resorption in the upper first premolars by micro–computed tomography (micro-CT) after three different rapid maxillary expansion appliances and two different activation rhythms. Materials and Methods The patients were divided into three groups; Hyrax, acrylic cap splint (ACS), and full coverage acrylic bonded (FCAB) appliances. Each group was then divided into the following two subgroups: rapid maxillary expansion (RME) and semirapid maxillary expansion (SRME). After expansion was completed, the appliances were stabilized for 12 weeks during the retention period. For each group, 10 premolars (for a total of 60 premolars) were scanned with the micro-CT (SkyScan). The reconstructed 3D images of each root sample were divided into six regions. The resorption craters on these six different root surfaces were analyzed by special CTAn (SkyScan) software for direct volumetric measurements. Kruskal-Wallis one-way analysis of variance and Mann-Whitney U tests were used for statistical analysis. Results The total volume of root resorption was less with FCAB than with ACS and Hyrax (P < .001). In all groups, a greater volume of resorption was found on the buccal surface than on the lingual surface (P < .001). No significant differences were found between the RME and SRME groups (P > .05). Conclusions All expansion appliances caused root resorption in the upper first premolar teeth, but FCAB may be safer in terms of root resorption. The resorption craters were generally concentrated on the buccal surface. There was no effect of activation rhythm on root resorption.

ABSTRACT Objective: To compare volumetric root resorption after rapid maxillary expansion (RME) between tooth-borne and tissue-borne appliances using CBCT. Repair in resorption cavities after 6 months of fixed retention was also compared. Materials and Methods: A sample of 33 subjects were randomly divided into two groups: Hyrax (n = 16) and Haas (n = 17). CBCT scans were taken 6 months before expansion, immediately after expansion, and 6 months after fixed retention. Mimics Innovation V 16.0 software was used for segmentation and volumetric measurement of 198 teeth. Bland-Altman plots, independent samples t test, repeated measures analysis of variance, and the Friedman test were used for statistical analysis. Results: Differences in root resorption after RME and repair after retention were not significant between the hyrax and Haas appliances or between male and female. Significant differences were found between preexpansion and postexpansion root volumes in the first premolars and molars—even in unattached second premolars. When the percentage of root volume loss is considered, no significant difference was found between the first premolar, second premolar, and first molar. Volumetric changes after 6 months of retention were not statistically significant. Conclusions: More resorption was observed in the Hyrax expander group. But it was not statistically significant. Repair was observed after 6 months of retention. Heavy RME forces affected premolars and molar similarly.

O objetivo deste estudo foi analisar os ruídos das articulações temporomandibulares (ATM) e a atividade eletromiográfica (EMG) dos músculos masseteres (MM) e temporais anteriores (TA) nos momentos pré e pós correção da mordida cruzada posterior funcional (MCPF) por meio da expansão rápida da maxila (ERM) com o uso do aparelho ortopédico Haas modificado. A amostra foi composta por 20 crianças (entre 6 e 12 anos de idade, de ambos gêneros) portadoras de MCPF. A eletrovibratografia (EVG) avaliou a presença de ruídos articulares. A eletromiografia (EMG) foi analisada nas situações clínicas de máxima contração voluntária em máxima intercuspidação habitual e mastigação habitual, direita e esquerda nos momentos pré tratamento (T1) e após três meses da finalização da ERM (T2). Os resultados mostraram que: não houve diferença estatística nos ruídos articulares entre o lado afetado e não afetado pela MCPF nos momentos T1 e T2, houve uma melhora do ruído articular com diminuição no pico de amplitude da vibração do lado da MCPF na comparação dos lados não afetados pela MCPF. No teste da EMG a avaliação em repouso e no teste funcional não mostrou diferenças estatisticamente significantes entre lado afetado e não afetado pela MCPF. Houve diferença estatística nas mastigações direita e esquerda tanto para MM como para os TA na mastigação do lado da MCPF sendo que atividade EMG aumentou para estes músculos no T1 do lado não afetado. Na comparação entre o lado afetado e não afetado, os MM e os TA aumentaram sua atividade EMG no T1 na mastigação do lado da MCPF e somente o MM apresentou aumento da atividade EMG na mastigação do lado não afetado pela MCPF. Na comparação entre os lados de MCPF no T1 com T2 e na comparação entre os lados não afetados pela MCPF na avaliação da mastigação de ambos os lados o MM apresentou aumento da atividade EMG nos momentos T1 e T2, com diferenças estatísticas significantes. Em conclusão, o tratamento precoce da ERM diminui a intensidade dos ruídos articulares do lado afetado pela MCPF e gera um equilíbrio nas funções mastigatórias após tratamento ortopédico da MCPF. Estes achados indicam que o tratamento precoce da MCPF favorece a obtenção de condições morfológicas e funcionais adequadas para um melhor desenvolvimento do sistema estomatognático.<br>The objective of this study was to analyze the temporomandibular joint (TMJ) noise and the electromyographic (EMG) activity of the masseter (MM) and anterior temporal (TA) muscles at the moments before and after correction of functional posterior crossbite (MCPF) by rapid expansion of the maxilla (ERM) with the use of the modified Haas orthopedic device. The sample consisted of 20 children (between 6 and 12 years of age, of both genders) with MCPF. Electrovibratography (EVG) evaluated the presence of joint noises. Electromyography (EMG) was analyzed in the clinical situations of maximum voluntary contraction in maximal habitual intercuspation and habitual chewing, right and left at the pre-treatment (T1) moments and after three months of the completion of ERM (T2). The results showed that: there was no statistical difference in articular noise between the affected and unaffected side of the MCPF at moments T1 and T2, there was an improvement in articular noise with a decrease in the peak of vibration amplitude on the MCPF side in the comparison of the non- affected side of the MCPF. In the EMG test, the evaluation at rest and in the functional test did not show statistically significant differences between the affected and non-affected side of the MCPF. There was a statistically significant difference in right and left chewing for both MM and TA in chewing on the MCPF side and EMG activity increased for these muscles in T1 on the unaffected side. In the comparison between the affected and unaffected side, MM and TA increased their EMG activity in T1 in chewing on the MCPF side and only MM showed increased EMG activity in chewing on the side not affected by MCPF. In the comparison between the MCPF sides in T1 with T2 and in the comparison between the sides not affected by MCPF in the chewing evaluation of both sides, the MM showed an increase in EMG activity at moments T1 and T2, with significant statistical differences. In conclusion, early treatment of MRE reduces the intensity of articular noises on the MCPF affected side and generates a balance in masticatory functions after orthopedic treatment of MCPF. These findings indicate that the early treatment of MCPF favors the achievement of morphological and functional conditions adequate for a better development of the stomatognathic system.

Objetivo: O objetivo deste trabalho é realçar a importância do tratamento ortodôntico intercetivo. Materiais e Métodos: Efetuou-se uma pesquisa na PubMed com as palavras-chave: ortodontia, má-oclusão, ortodontia intercetiva, expansão maxilar, combinadas em pares com o operador booleano «AND». O limite temporal foi de 1961 a 2019. As seleções dos estudos obedeceram aos critérios de inclusão e exclusão previamente definidos. Obtiveram-se sessenta e três referências bibliográficas. Incluíram-se livros e artigos considerados pertinentes para esta pesquisa. Resultados: Verificou-se que a disjunção da sutura maxilar é o tratamento de referência para as anomalias transversais, especialmente a endognatia maxilar. Em relação às anomalias alveolares, os dois aparelhos mais utilizados são a placa palatina com ou sem planos de elevação de mordida e o quadrihélice. Conclusão: A ortodontia intercetiva é essencial para evitar graves problemas dentários, alveolares e esqueléticos. O diagnóstico precoce na observação das dismorfoses e deteção das etiologias é fundamental.<br>Objective: The aim of this work is to highlight the importance of interceptive orthodontic treatment. Materials and Methods: A search was carried out in PubMed with the keywords: orthodontics, malocclusion, interceptive orthodontics, maxillary expansion, combined in pairs with the Boolean operator «AND». The time limit was from 1961 to 2019. The selections of studies followed the inclusion and exclusion criteria previously defined. Sixty-three bibliographical references were obtained. Books and articles considered relevant to this research were included. Results: It was found that maxillary suture disjunction is the reference treatment for transverse anomalies, especially maxillary endognathia. Regarding alveolar anomalies, the two most used devices are the palatal plate with or without bite elevation planes and the quadrihelix. Conclusion: Interceptive orthodontics is essential to avoid serious dental, alveolar and skeletal problems. Early diagnosis in the observation of dysmorphosis and detection of etiologies is essential.