ABSTRACT
Four premolar extractions is a successful protocol to treat Class I malocclusion, but it is a less efficient way when compared with other Class II treatment protocols. Objective: The objective of this study was to evaluate the influence of anteroposterior discrepancy on the success of four premolar extractions protocol. For that, treatment efficiency of Class I and complete Class II malocclusions, treated with four premolar extractions were compared. Methods: A sample of 107 records from 75 Class I (mean age of 13.98 years - group 1) and 32 Class II (mean age of 13.19 years - group 2) malocclusion patients treated with four premolar extractions was selected. The initial and final occlusal status of each patient was evaluated on dental casts with the PAR index. The treatment time was calculated based on the clinical charts, and the treatment efficiency was obtained by the ratio between the percentage of PAR reduction and treatment time. The PAR index and its components, the treatment time and the treatment efficiency of the groups were statistically compared with t tests and Mann-Whitney U-test. Results: The Class II malocclusion patients had a greater final PAR index than Class I malocclusion patients, and similar duration (Class I - 28.95 mo. and Class II - 28.10 mo.) and treatment efficiency. Conclusion: The treatment of the complete Class II malocclusion with four premolar extractions presented worse occlusal results than Class I malocclusion owing to incomplete molar relationship correction. .
Subject(s)
Humans , Male , Female , Child , Adolescent , Adult , Young Adult , Bicuspid/surgery , Malocclusion, Angle Class I/therapy , Malocclusion, Angle Class II/therapy , Serial Extraction/methods , Age Factors , Regression Analysis , Retrospective Studies , Severity of Illness Index , Sex Factors , Statistics, Nonparametric , Time Factors , Treatment OutcomeABSTRACT
Class III malocclusions are considered one of the most complex and difficult orthodontic problems to diagnose and treat. Skeletal and/or dental asymmetries in patients presenting with Class III malocclusions can worsen the prognosis. Recognizing the dentoalveolar and skeletal characteristics of subdivision malocclusions and their treatment possibilities is essential for a favorable nonsurgical correction. Therefore, this article presents a nonsurgical asymmetric extraction approach to Class III subdivision malocclusion treatment which can significantly improve the occlusal and facial discrepancies.
Subject(s)
Adolescent , Child , Humans , Dental Cements , Malocclusion/therapy , OrthopedicsABSTRACT
This article reports the case of a 19-year-old young man with Class III malocclusion and posterior crossbite with concerns about temporomandibular disorder (TMD), esthetics and functional problems. Surgical-orthodontic treatment was carried out by decompensation of the mandibular incisors and segmentation of the maxilla in 4 pieces, which allowed expansion and advancement. Remission of the signs and symptoms occurred after surgical-orthodontic intervention. The maxillary dental arch presented normal transverse dimension. Satisfactory static and functional occlusion and esthetic results were achieved and remained stable. Three years after the surgical-orthodontic treatment, no TMD sign or symptom was observed and the occlusal results had not changed. When vertical or horizontal movements of the maxilla in the presence of moderate maxillary constriction are necessary, segmental LeFort I osteotomy can be an important part of treatment planning.
Subject(s)
Humans , Male , Young Adult , Malocclusion, Angle Class III/surgery , Osteotomy, Le Fort/methods , Temporomandibular Joint Disorders/surgery , Malocclusion, Angle Class III/complications , Palatal Expansion Technique , Temporomandibular Joint Disorders/etiology , Young AdultABSTRACT
O objetivo deste estudo retrospectivo foi comparar os resultados oclusais e a eficiência do tratamento das más oclusões de Classe I e de Classe II completa, ambas tratadas com extrações de quatro pré-molares. A eficiência do tratamento foi definida como a porcentagem de alterações oclusais pelo tempo de tratamento. O Grupo 1, constituído por 75 pacientes que apresentavam inicialmente má oclusão de Classe I, apresentava idade inicial média de 13.98 anos (D.P.: 2.08, mín.: 10.54 e máx.: 23.13), e o Grupo 2, composto por 32 pacientes que apresentavam inicialmente má oclusão de Classe II completa, bilateral, apresentava idade inicial média de 13.19 anos (D.P.: 1.58, mín.: 10.48 anos e máx.: 18.58 anos). As avaliações oclusais foram realizadas em modelos de gesso dos pacientes nas fases inicial e final utilizando os índices PAR e IPT. Os índices oclusais, o tempo de tratamento e o grau de eficiência dos grupos foram comparados pelo teste t. Os resultados demonstraram que o Grupo 1 obteve melhores resultados oclusais e maior porcentagem de alterações oclusais do que o Grupo 2. Entretanto, não houve diferença significante no tempo de tratamento e na eficiência dos protocolos de tratamento entre os grupos avaliados.
The objective of this retrospective study was to compare the occlusal outcomes and the treatment efficiency in the treatment of the Class I and Class II complete malocclusions, both treated with extraction of four premolars. The treatment efficiency was defined as the percentage of occlusal changes by the treatment time. The Group 1, composed by 75 patients who presented initially Class I malocclusion, presented initial mean age of 13.98 years (S.D.: 2.08, min.: 10.54 years and max.: 23.13 years), and the Group 2, composed by 32 patients who presented initially complete Class II, bilateral, presented initial mean age of 13.19 years (S.D.: 1.58, min.: 10.48 years and max.: 18.58 years). The occlusal evaluations were accomplished in study models of the patients in the initial and final phases using the indexes PAR and TPI. The occlusal indexes, the treatment time and efficiency of the groups were compared with the t test. The results demonstrated that the Group 1 achieved better occlusal outcomes and greater percentage of occlusal changes than the Group 2. However, there was no significant difference in the treatment time and efficiency in the treatment protocols between the groups considered.
Subject(s)
Humans , Adolescent , Bicuspid , Malocclusion, Angle Class I , Malocclusion, Angle Class II , Occlusal Adjustment , Serial ExtractionABSTRACT
A dificuldade no correto registro de relação cêntrica opõe-se ao fato de que o cirurgião-dentista necessita realizar a maioria dos seus trabalhos nessa posição craniomandibular. O sistema R.O.C.A. (Relacion Oclusal Centrica Armonica) é proposto para ser utilizado pelo clínico, para obter o registro preciso da relação cêntrica. Propriamente empregado, o paciente é capaz de fechar a mandíbula em relação cêntrica sem auxílio, eliminando a possibilidade do erro operatório durante as manobras de manipulação mandibular. Seu uso clínico é simples e eficiente, facilitando o trabalho do profissional.