Effect Of First Premolar Extraction On The Smile Micro-aesthetics In The Treatment Of Bimaxillary Protrusion

INTRODUCTION:Bimaxillary protrusion is a malocclusion wherein the patient presents with increased lip procumbency and increased proclination of maxillary and mandibular incisor teeth giving a bad appearance to the patient.The patient‘s main concern and goal in seeking orthodontic treatment is the betterment of facial and dental appearance.The aim of this case report is to evaluate the pre-and post-treatment microaesthetics in a patient treated with the extraction of maxillary first premolars and mandibular second premolars METHODOLOGY:A female patient aged 11 years attended the Second Affiliated Hospital of Dalian Medical University complaining of protrusive lips.The clinical and radiographic evaluations lead to the diagnosis of bimaxillary protrusion on a class II skeletal base.The four pre-and post-treatment microaesthetic components were assessed by measuring maxillary central incisor crown width-height ratio,connectors in the proximal contact areas of maxillary anterior teeth,level of the gingival zenith of the maxillary lateral incisor and golden percentage of the anterior teeth using the patient‘s plaster casts and intraoral frontal photographs.The patient was treated with extraction of upper first bicuspids and lower second bicuspids and fixed pre-adjusted edgewise appliance.Result:Total treatment time was 21 months,post-treatment cephalometric analysis showed upper and lower incisor uprighting(?SN 93?,IMPA 93?)which resulted in a betterment of facial profile.Post-treatment measurements of the smile microaesthetic components show a considerable difference with the pre-treatment values.Discussion:The effect of extraction of upper first premolar on the smile microaesthetics was evaluated during this case.To achieve maximum aesthetics for an ideal smile is not possible unless all the components making up the smile are analyzed pre-and post-treatment and more realistic treatment goals are set.The numerical values used to measure the aesthetics always remain in a range rather than being a fixed value.Conclusion:It can be concluded that premolar extraction to decrease the facial convexity is an acceptable treatment method.Post-treatment evaluation of the microaesthetic components revealed that ideal values are difficult to achieve.It becomes imperative to focus on the microaesthetics of the smile in the finishing stages of the treatment especially in extraction cases.