Association of Class II Division 2 malocclusion with dental development anomalies

Aim: The aim of this study is to investigate the existence of an association between Class II Division 2 malocclusion and some dental development anomalies.Materials and methods: Using the initial orthodontic records, 137 Class II Division 2 malocclusions were examined. For each patient, the presence of the following dental development anomalies was determined: tooth impaction, tooth agenesis, upper lateral incisor microdontia, tooth transpositions and supernumerary teeth.Results: 57,7% of patients were diagnosed with at least one of the dental anomalies studied. In the total sample the prevalence rates were determined as follows: 20,4% of palatal maxillary canine impaction, 27,6% of third molar agenesis, 9,5% of upper lateral incisor agenesis, 37,0% of total tooth agenesis and 13,9% of upper lateral incisor microdontia. No tooth transpositions or supernumerary teeth were found in any patient.Conclusions: By comparing our results with prevalence studies of the dental anomalies studied in the general population, we can conclude that palatal maxillary canine impaction, tooth agenesis and upper lateral incisor microdontia are strongly associated with Class II Division 2 malocclusion.Objetivo O objetivo deste estudo é investigar a existência de uma associação da má oclusão de Classe II Divisão 2 com algumas anomalias do desenvolvimento dentário. Materiais e métodos Recorrendo aos registos ortodônticos iniciais, foram examinadas 137 más oclusões de Classe II Divisão 2. Para cada paciente, foi determinada a presença das seguintes anomalias do desenvolvimento dentário: inclusão dentária, agenesia dentária, microdontia do incisivo lateral superior, transposições dentárias e dentes supranumerários. Resultados Em 57,7% dos pacientes foi diagnosticada a presença de pelo menos uma das anomalias dentárias estudadas. Na amostra total foram determinadas prevalências de 20,4% de inclusão canina maxilar por palatino, 27,6% de agenesia do terceiro molar, 9,5% de agenesia do incisivo lateral superior, 37,0% de agenesia dentária total e 13,9% de microdontia do incisivo lateral superior. Nenhum paciente exibia transposições ou dentes supranumerários. Conclusões Da comparação dos resultados obtidos com estudos de prevalência na população geral das anomalias dentárias avaliadas é possível concluir que existe uma forte associação da inclusão canina maxilar por palatino, da agenesia dentária e da microdontia do incisivo lateral superior com a má oclusão de Classe II Divisão 2

Skeletal and dental changes following functional regulator therapy on class II patients

Craniofacial growth in 100 patients treated with the functional regulator of Frankel for about 24 months was compared with craniofacial growth seen in a matched group of untreated persons with Class II malocclusion. Both conventional and geometric cephalometric analyses were used to evaluate the skeletal and dental adaptations. This study shows several clear effects of treatment in either of two age ranges considered. The principal skeletal effect was advancement of the mandible along the direction of the facial axis. This advancement resulted in increases in mandibular length and in vertical facial dimensions. There was little effect of treatment upon maxillary skeletal structures with the exception of point A, which moved slightly posteriorly. Dentoalveolar adaptations due to treatment included a decrease in the normal forward movement of the upper molar and an increase in the normal vertical movement of the lower molar. There was a 2-mm posterior movement of the tip of the upper incisor but minimal anterior tipping of the lower incisor.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/25601/1/0000148.pd