The Aetiology, Diagnosis and Management of Mandibular Asymmetry

An understanding of the aetiology of mandibular asymmetry and a thorough methodical diagnostic approach is essential for the appropriate management of patients presenting with dentofacial asymmetry. The aim of this review article is to describe the developmental, pathological, traumatic and functional causes of mandibular asymmetry, to provide a guide to diagnosis through clinical examination and special investigations and, finally, to outline the management of patients presenting with a mandibular asymmetry, focusing particularly on the treatment of developmental asymmetries. Clinical Relevance: This article presents a review of the aetiology, diagnosis and management of mandibular asymmetries with a particular focus on developmental asymmetries. Ortho Update 2008; 1: 44-52 Matthew SY Chia, BDS, MFDS RCS(Eng), MSc, MOrth, FTTA in Orthodontics, Eastman Dental Hospital and Mayday Hospital, London, Farhad B Naini, BDS, FDS RCS, MSc, MOrth RCS, FDSOrth RCS, Consultant Orthodontist, St George’s and Kingston Hospitals and Daljit S Gill, BDS(Hons), BSc(Hons), MSc, FDS RCS, MOrth, FDSOrth RCS, Consultant Orthodontist/Hon Senior Lecturer, UCL Eastman Dental Institute, London, Honorary Consultant Orthodontist, Great Ormond Street Hospital, London, UK. The word symmetry is derived from the Greek word symmetria which means ‘of like measure’. Symmetry is defined as correspondence in size, shape and relative position of parts on opposite sides of a dividing line or median plane. Asymmetry is described as a lack or absence of symmetry. When applying this to the human face, it illustrates an imbalance or disproportionality between the right and left sides. A degree of asymmetry is normal and acceptable in the average face. It may be caused by a range of factors that affect the underlying skeletal structure or soft tissue drape. However, the importance of early diagnosis and the detection of progressive causative conditions is essential for the management of facial asymmetry. This article will focus on asymmetries of the mandible and on some of the aspects of maxillary asymmetry. The causes of mandibular asymmetry can be divided into (Table 1):  Developmental;  Pathological;  Traumatic;  Functional. Matthew SY Chia