Class II malocclusion with deep overbite: a sequential approach

Abstract

Objective: The aim of this case report was to evaluate the results of deep overbite correction by the segmented arch technique. Methods: The first stage of the treatment was performed with this technique to intrude incisors and canines. A maxillary transpalatal bar and a mandibular lingual arch using 0.051-in archwire were employed associated to a facial bow, anchored primarily with occipital pull and, after molar relationship correction, changed to high pull. Results: Upper incisors presented a great amount of intrusion and some palatal root inclination as programmed in the treatment plan. The skeletal mandibular response was favorable to achieve profile balance. Periapical radiograph showed rounded apex of incisor roots, expected in any orthodontic intrusion movement. Conclusion:The clinical results present the successful approach to deep overbite malocclusion.Keywords: Angle Class II malocclusion. Extraoral traction appliances. Tooth movement. Objetivo: o objetivo desse relato de caso clínico foi avaliar os resultados da correção da sobremordida exagerada por meio da técnica do arco segmentado. Métodos: na primeira etapa do tratamento, utilizou-se essa técnica para intrusão dos incisivos e caninos. Em seguida, foram confeccionados e instalados uma barra transpalatina superior e um arco lingual inferior, ambos com fio de 0,051" de espessura, sendo associados ao arco facial ancorado, primeiramente, em tração occipital e, após a correção da chave de oclusão, foi modificada para tração parietal. Resultados: os incisivos superiores apresentaram grande quantidade de intrusão com discreta inclinação palatal das raí-zes, conforme determinado no plano de tratamento. A resposta mandibular foi favorável, possibilitando o alcance de perfil mais harmonioso. Nas radiografias periapicais, observou-se suave arredondamento apical nas raízes dos incisivos, compatível com movimento de intrusão. Conclusão: os resultados clínicos conferem sucesso na abordagem da correção da sobremordida exagerada.Palavras-chave: Má oclusão de Angle Classe II. Aparelhos de tração extrabucal. Movimentação dentária.

Comparison of two types of biomecanics for deep overbite correction

“…The anti-clockwise rotation during puberal growth spurt, representative of brachiocephalic pattern, was not observed probably due the molar extrusions, corroborating with the studies of some authors [13][14][15][16][17][18][19] . The total cephalometric superimposition between T 0 and T 1 of Group 2 showed forward displacement and anticlockwise rotation of the mandible, together with profile improvement.…”

“…Nevertheless, in the mandibular arch molar intrusion was observed to decrease the Spee curve, contributing for an average 0.4 º decrease of SN.GoGn and anti-clockwise rotation of the mandible (Tables 2 and 3) (Figure 6). These data were corroborated by Baccetti et al 15 and Martinelli et al 19 , who reported that the overbite correction resulted of the intrusion of maxillary incisors as well as mandibular incisors accompanied by mandibular growth.…”

“…After this, in Groups 1 and 2 continuous arches of leveling were sequentially used to maintain Spee curve alterations and obtain the best possible mandibular displacement in downward and forward directions during growth spurt. This approach is corroborated by Martinelli et al 19 , who reported that the favorable mandibular displacement enables achieving the best harmonious profile, and by Woods 18 who affirmed that the extrusive movement of only 1 mm of maxillary and mandibular molars reduces effectively the overbite between 1.5 to 2.5 mm.…”

“…The main strategy of deep bite treatment for both groups consisted of combined extrusion of the posterior teeth, intrusion and vestibular inclination of the anterior teeth (maxillary and mandibular incisors). This is confirmed in the literature because the decision of extrusion or intrusion should be based on skeletal pattern, vertical pattern, facial esthetic, growth spurt, occlusal plane, severity of final malocclusion, occlusion stability or the combination of these factors 1,4-7,10, [13][14][15][16][17][18][19] . At first in Group 1 segmented arches (Rickets' technique) 0.018´x 0.025´ were used for intrusion and projection of maxillary and mandibular incisors, enabling the decrease of deep overbite, with anterior brackets glued in the most possible incisal level.…”

“…For Nanda 4 , the stability of deep bite treatment depends on specific dental correction (intrusion, extrusion or inclination), growth spurt and neuromuscular adaptation. The few studies that dealt with this subject indicate that active treatment is able to induce a moderate improvement of the overbite, but unfortunately the few studies assessing the effects of orthodontic treatment in deep bite patients either did not include untreated control subjects [13][14][15][16][17][18] or used controls with normal overbite values 19 . Due to the scarcity of studies investigating skeletal and dental modifications caused by deep overbite treatment, two types of biomechanics with fixed appliances were searched.…”