RESUMO
Growth modification is a feasible approach for the treatment of skeletal Class II malocclusion. A positive association was found between the lateral functional shift of the mandible due to occlusal prematurities and skeletal changes. This finding is reminiscent of an equivalent anteroposterior skeletal effect of the anterior functional shift of the mandible. Inclined planes can be considered as a form of premature contact. In this case, bonded occlusal maxillary and mandibular bite raisers were used to create occlusal prematurities artificially. These bonded inclined bite raisers are used in conjunction with full-time light short Class II elastics. The results showed an improvement in profile convexity and achievement of Class I canines and molars. The bonded inclined bite raisers combined with light and short intermaxillary elastics can correct Class II malocclusion and improve the soft tissue profile.
Assuntos
Má Oclusão Classe II de Angle/diagnóstico por imagem , Má Oclusão Classe II de Angle/terapia , Cefalometria , Oclusão Dentária , Humanos , Mandíbula , MaxilaRESUMO
INTRODUCTION: This study aimed to identify significant factors affecting the spontaneous angular changes of impacted mandibular third molars as a result of second molar protraction. Temporary skeletal anchorage devices in the missing mandibular first molar (ML-6) or missing deciduous mandibular second molar (ML-E) with missing succedaneous premolar spaces provided traction. METHODS: Forty-one mandibular third molars of 34 patients (10 male and 24 female; mean age 18.3 ± 3.7 years) that erupted after second molar protraction were included in this study. They were classified into upright (U) and tilted (T) groups. Linear and angular measurements were performed at the time of treatment initiation (T1) and of ML-6 or ML-E space closure (T2). Regression analyses were used to identify significant factors related to third molar uprighting. RESULTS: Nolla stage (odds ratio [OR] 4.1), sex (OR 0.003 for male), third molar angulation at T1 (OR 1.1), missing tooth space (OR 0.006), rate of third molar eruption (OR 23.3), and rate of second molar protraction (OR 0.2) significantly affected third molar uprighting. Age, third molar angulation at T1, rate of third molar eruption, and rate of second molar protraction were significant factors for predicting third molar angulation at T2. CONCLUSIONS: Available space for third molar eruption before and after second molar protraction is not associated with uprighting of erupting third molars. Older patients whose third molars are in greater Nolla stage, are in a more upright position at T1, and have a greater eruption rate have a greater chance for third molar uprighting. Alternatively, an increase in second molar protraction rate results in mesial tipping of the third molars.
Assuntos
Má Oclusão/prevenção & controle , Má Oclusão/fisiopatologia , Mandíbula/fisiopatologia , Dente Serotino/fisiopatologia , Dente Impactado/fisiopatologia , Adolescente , Adulto , Pontos de Referência Anatômicos , Dente Pré-Molar , Feminino , Humanos , Masculino , Má Oclusão/diagnóstico por imagem , Mandíbula/anatomia & histologia , Mandíbula/diagnóstico por imagem , Dente Molar/anatomia & histologia , Dente Molar/diagnóstico por imagem , Dente Molar/fisiopatologia , Dente Serotino/anatomia & histologia , Dente Serotino/diagnóstico por imagem , Aparelhos Ortodônticos , Fechamento de Espaço Ortodôntico , Ortodontia Corretiva , Erupção Dentária , Dente Decíduo , Dente Impactado/complicações , Dente Impactado/diagnóstico por imagem , Adulto JovemRESUMO
INTRODUCTION: The purpose of this study was to evaluate the efficiency of corticotomy-facilitated orthodontics and piezocision in rapid canine retraction. METHODS: The sample consisted of 20 patients (15-25 years old) with Class II Division 1 malocclusions. The suggested treatment plan was extraction of the maxillary first premolars with subsequent canine retraction. The sample was divided into 2 equal groups. In the first group, 1 side of the maxillary arch was randomly chosen for treatment with corticotomy, and in the second group, piezocision treatment was used. The contralateral sides of both groups served as the controls. Cuts and perforations were performed with a piezotome, and canine retraction was initiated bilaterally in both groups with closed-coil nickel-titanium springs that applied 150 g of force on each side. The following variables were examined over a 3-month follow-up period: rate of canine crown tip, molar anchorage loss, canine rotation, canine inclination, canine root resorption, plaque index, gingival index, probing depth, attachment level, and gingival recession. The rate of canine crown tip was assessed every 2 weeks after the start of canine retraction at 6 time points. RESULTS: The rates of canine crown tip were greater in the experimental sides than in the control sides in both groups. Corticotomies produced greater rates of canine movement than did piezocision at 4 time points. Canine root resorption was greater in the control sides. The remaining studied variables exhibited no differences between the control and the experimental sides. CONCLUSIONS: Corticotomy-facilitated orthodontics and piezocision are efficient treatment modalities for accelerating canine retraction.