RESUMO
INTRODUCTION: The aim of this cross-sectional study was to investigate maxillomandibular morphology in hyperdivergent and hypodivergent individuals, using 3D surface models generated by cone-beam computed tomography (CBCT). METHODS: The sample consisted of 60 CBCTs (30 males, 30 females) patients aged 12-30 years, divided into two groups comprising hyperdivergent (≥35°) and hypodivergent (≤30°) individuals, according to the mandibular plane (MP) angle. Multiplanar reconstructions were used to mark the landmarks, and 3D surface models were created to evaluate structures of the maxillomandibular complex, including condyle, ramus, symphysis and palatal height. Intergroup comparisons were performed by independent t-test. Pearson's correlation test was used (P < .05) to evaluate the correlation of the MP angle with the angles and linear measurements of other structures. RESULTS: Significant differences were found between the groups regarding condylar width, ramus height, condylar plus ramus height, mandibular length, gonial angle, palatal plane angle and palatal-mandibular angle. No differences (P > .05) were found for the condylar height, symphysis inclination angle or palatal height. Correlations (P < .05) were found between the MP angle and structures of the maxillomandibular complex. CONCLUSIONS: Hyperdivergent (MP ≥ 35°) and hypodivergent (MP ≤ 30°) individuals present different skeletal morphology regarding condylar width, ramus height, condylar plus ramus height, mandibular length, gonial angle, palatal plane angle and palatal-mandibular angle. There is a significant correlation between MP angle and morphological structures such as condyle, ramus, symphysis, palatal plane angle and palatal-mandibular angle.
Assuntos
Tomografia Computadorizada de Feixe Cônico , Mandíbula , Masculino , Feminino , Humanos , Estudos Transversais , Mandíbula/diagnóstico por imagem , Mandíbula/anatomia & histologia , Tomografia Computadorizada de Feixe Cônico/métodos , Cefalometria/métodos , Côndilo Mandibular/diagnóstico por imagemRESUMO
Implants obtained popularity in Orthodontics by to make easy the maximum anchorage with the minimal patient׳s compliance. In this context, osseointegrated implants has been frequently used as auxiliaries of orthodontic treatments, substituting in some cases inter maxillaries elastics and extra oral appliances. These implants show as advantage a independence in opposite the patient׳s compliance, the anchorage possibility in periodontal loss cases, over there an esthetic improvement and the comfort propitiated, showing more expected results. This article approach the orthodontic treatment of a clinic case of Class II, division 1 malocclusion, non-extraction accomplished and with palatal implant to distalization of latter teeth.
RESUMO
OBJECTIVE: The aim of this study was to assess the magnitude of occlusal changes in individuals with unilateral cleft lip and palate (CLP). The study was conducted on study cast models of 25 subjects, 14 men and 11 women aged from 7 to 20 years, without previous orthodontic treatment and with surgical repair carried out at São Marcos Hospital, Teresina, Piauí State, Brazil. METHODS: The cast models were assessed by three orthodontists based on the occlusal scores established by Atack et al., whose scores range from 1 to 5, according to the magnitude of transverse and sagittal changes. RESULTS: Intra and inter-observer reproducibility of occlusal scores was satisfactory and statistically significant according to the Spearman correlation test with significance level set at 5%. With regard to the distribution of occlusal scores, 30.67% of the subjects achieved scores 1 and 2, 22% score 3 and 47.53% achieved scores 4 and 5. CONCLUSIONS: Four was the score most frequently assigned by the observers, disclosing a high degree of transverse and sagittal disorders in the occlusion of patients.
Assuntos
Fenda Labial/complicações , Fissura Palatina/complicações , Oclusão Dentária , Má Oclusão/etiologia , Maxila/crescimento & desenvolvimento , Adolescente , Criança , Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Técnica de Fundição Odontológica , Feminino , Humanos , Masculino , Má Oclusão/diagnóstico , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Adulto JovemRESUMO
OBJECTIVE: The purpose of this study was to evaluate, in vitro, the bond strength of brackets bonded to premolars previously subjected to bleaching with a 35% hydrogen peroxide. METHODS: Twenty one healthy premolars were selected and randomly divided into three groups (n = 7). Group I (G1) included teeth that were not submitted to bleaching. The enamel surfaces of Groups II (G2) and III (G3) were submitted to a bleaching process with 35% hydrogen peroxide (Whiteness HP Maxx). On Group II (G2), after bleaching, the teeth were stored for 24 hours in distilled water at 98.6 °F, and then, premolar metallic brackets were bonded using Transbond XT (3M) resin. Group III (G3) was submitted to the same procedure seven days after bleaching. After bonding, all teeth were stored in distilled water at 98.6 °F for 24 hours. All groups were submitted to a traction test using an EMIC DL2000 universal testing machine at a speed of 0.5 mm/min. RESULTS AND CONCLUSION: The bracket resistance to debonding was compared between the groups by the Kruskal-Wallis nonparametric test (p < 0.05) and it was verified that the bleaching agent significantly reduced bracket adhesion when bonded 24 hours after bleaching. However, seven days after bleaching, there was no significant difference on the resistance to debonding among groups G1 (19,52 kgf) and G3 (18,44 kgf), meaning that it is necessary to wait longer after bleaching to bond brackets.
Assuntos
Colagem Dentária/métodos , Descolagem Dentária/métodos , Esmalte Dentário/efeitos dos fármacos , Peróxido de Hidrogênio/química , Braquetes Ortodônticos , Clareadores Dentários/química , Clareamento Dental/métodos , Dente Pré-Molar , Humanos , Resistência ao Cisalhamento , Estatísticas não ParamétricasRESUMO
The objective of this clinical case is to suggest a treatment approach for impaction of the maxillary first permanent molars. This approach allows access to the partially erupted tooth for orthodontic bonding and utilization of loops for distalization. An important detail is the non inclusion of the primary second molar in the orthodontic mechanics, in order to reduce the risk of early loss and preserve this tooth until exfoliation.
Assuntos
Dente Molar/fisiopatologia , Técnicas de Movimentação Dentária/métodos , Dente Impactado/terapia , Criança , Dentição Permanente , Humanos , Maxila , Aparelhos Ortodônticos , Técnicas de Movimentação Dentária/instrumentação , Dente DecíduoRESUMO
OBJECTIVES: To determine the mechanical characteristics of beta-titanium T-loops with and without helices, with 0 and 180 degree gable bends and constructed from 0.017 inch x 0.025 inch and 0.019 inch x 0.025 inch wire. METHODS: Forty beta-titanium T-loops were centrally positioned in a universal testing machine. The horizontal force and the moment/force ratios during activation were recorded at 1 mm intervals, up to a maximum of 7 mm. The data were analysed with analysis of variance complemented by the Tukey test for multiple comparisons. RESULTS: The results demonstrated that the transverse section of the wire had the greatest effect on the horizontal force produced by the loops. Significantly lower levels of horizontal force were obtained with loops made with the smaller 0.017 inch x 0.025 inch wire. Loops with gable bends yielded high moment/force ratios, whereas loops without gable bends had low moment/force ratios. In general, T-loops with helices yielded lower magnitudes of horizontal force and moment/force ratios than plain T-loops. CONCLUSIONS: The horizontal forces and moment/force ratios generated by plain T-loops with 180 degree gable bends yielded more adequate force systems. Incorporation of helices in the design of T-loops seems to be unnecessary.