Overbite Correction and Smile Aesthetics

Achievement of optimum smile aesthetics during orthodontic treatment has recently been the focus of several published articles in the orthodontic literature. Authors speculate that overbite correction, specifically maxillary incisor intrusion, will lead to flattening of the smile arc and consequently reduce smile attractiveness. The purpose of this prospective clinical study was to investigate differences in outcomes from two common procedures used to reduce deep overbite: maxillary incisor intrusion using an intrusion arch and posterior tooth eruption using an anterior bite plate. Pretreatment and postoverbite correction records were gathered from 20 patients who presented with deep overbite malocclusions to the Virginia Commonwealth University orthodontic clinic. Both the intrusion arch and bite plate procedures effectively reduced overbite significantly over a relatively short period of treatment. Intrusion arch patients displayed significant reductions in maxillary incisor display (lip to tooth) accompanying documented incisor intrusion. Half of the patients in both groups experienced flattening of the smile arc in agreement with previous studies showing similar changes in orthodontic patients in general. There was no greater tendency for flattening to occur in either group. Changes in the smile arc are likely due to other factors involved in orthodontic tooth alignment and are not necessarily attributable to the overbite correction method employed during treatment.