Main clinical approaches to orthognathic surgery for class II open bite and genioplasty patients: a brief systematic review

Abstract

Introduction: Orthognathic surgery (OS) is used to improve the patient's facial appearance and to correct maxillary and mandibular deformities resulting from malocclusions, disease, or trauma. In this context, genioplasty is a procedure to correct an aesthetic and functional deformity of the chin region, improving the contour. Moreover, anterior open bite (AOB) is the lack of vertical contact or negative overbite between the anterior teeth of the superior and inferior arches when the posterior teeth are in occlusion. Objective: The present study aimed to perform a brief systematic review with risk of bias analysis by funnel plot to highlight the main clinical approaches of orthognathic surgery in class II patients with open bites and also concerning genioplasty. Methods: The research was carried out from February 2022 to May 2022 and developed based on Scopus, PubMed, Science Direct, Scielo, and Google Scholar. The quality of the studies was based on the GRADE instrument and the risk of bias was analyzed according to the Cochrane instrument. Results and Conclusion: A total of 115 articles were found. In total, 57 articles were fully evaluated and 34 were included and evaluated in this study. And of the total of 34 articles, only 11 articles were developed as the main clinical results. A total of 32 articles were excluded because they did not meet the GRADE classification, and 16 were excluded because they were at risk of bias. The symmetric funnel plot does not suggest a risk of bias between the small sample size studies. A retrospective observational study compared 57 patient charts on treatment outcomes for anterior occlusion and vertical skeletal stability after maxillary or mandibular surgery to correct Class II malocclusion with a mild to moderate open bite. After surgery, 87% of Le Fort I patients and 63% of patients with bilateral sagittal split osteotomy had a positive overbite, and at the 6-month follow-up, the percentages were 90% and 74%, respectively. Another study showed Class II patients had significantly greater amounts of lateral and lower translation than class III patients. Also, genioplasty represents one of the most common auxiliary procedures and may be associated with corrective surgery for dentofacial dysmorphisms. However, care must be taken with mental nerve injuries, asymmetries, and intraoperative bleeding are the main immediate complications.