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24 Dental Tribune Middle East & Africa Edition | November-December 2014CLINICAL Case report surgical correction of a class III malocclusion in an adult Figure 1. Pre-treatment extra-oral Figure 2. Pre-treatment intra-oral no other abnormal signs. After the analysis of the pho- tographs, the casts and ra- diographs, it was decided to approach his problems as a skeletal Class III malocclusion with an anterior cross bite and a lower deviated midline (2). Treatment Objectives The treatment objectives (3) were to obtain a harmonious facial profile by decreasing the protusion of the mandible, im- prove the occlusion, including correction of the anterior cross- bite, establishment of ideal over- jet and overbite, achievement of a functional molar relationship; and place the dental midlines in the middle of the patient’s face. We planned: • To set back the mandible to correct the prognathism and the midline deviation. • To relieve the proclined max- illary incisor position and to re- lieve the dental compensations. • To relieve the dental com- pensations by straightening the mandibular incisors to an up- right position over basal bone. Treatment Alternatives The first alternative was ortho- dontic treatment with extraction of 4 premolars. Through the re- traction of the mandibular ante- rior teeth, the anterior crossbite and Class III molar relationships would be corrected and the concave facial profile would be camouflaged. Nevertheless, the mandibular incisors were not suitable for much distal move- ment because of the thin tra- becular bone in the mandibular anterior area that could damage the periodontal tissues by gin- gival recession, fenestration or dehiscence. The second alternative was combined surgical and ortho- dontic treatment. The anterior crossbite would be corrected with a single-jaw surgery: a mandibular setback. The con- cave profile would be improved By Dr. Fabien Depardieu T his case report describes a successful orthognath- ic treatment of a skel- etal Class III malocclusion with mandibular prognathism in an adult individual. The patient with Class III malocclusion, having mandibular excess in sagittal and vertical plane was treated with orthodontics, bi- lateral sagittal split osteotomy. The surgical-orthodontic com- bination therapy has resulted in near-normal skeletal, dental and soft tissue relationship, with marked improvement in the fa- cial esthetics in turn, has helped the patient to improve the self- confidence level. The interdis- ciplinary approach is the treat- ment of choice in most of the skeletal malocclusions (1). Keywords: Class III malocclu- sion, decompensation, Orthog- nathic Surgery, Bilateral sagittal split osteotomy, prognathism, surgical orthodontic treatment. Introduction The Skeletal Class III malocclu- sion is characterized by mandib- ular prognathism, maxillary de- ficiency or both. Clinically, these patients exhibit a concave facial profile, a retrusive nasomaxil- lary area and a prominent lower third of the face. The lower lip is often protruded relative to the upper lip. The upper arch is usu- ally narrower than the lower, and the overjet and overbite can range from reduced to reverse. The effect of environmental factors and oral function on the etiological factors of a Class III malocclusion is not completely understood. However, there is a definite familial and racial tendency to mandibular progna- thism. For many Class III maloc- clusions, surgical treatment can be the best alternative. Depend- ing on the amount of skeletal discrepancy, surgical correction may consist of mandibular set- back, maxillary advancement or a combination of mandibular and maxillary procedures. After surgical correction of the skel- etal discrepancy, the occlusion is usually finished orthodontically to a Class I relationship. How- ever, if surgical treatment is not performed, and the final molar relationship is Class III or Class I, there are challenges specific to the static and functional Class III occlusion that must be consid- ered. Sometimes a Class III rela- tionship is caused by a forward shift of the mandible to avoid incisal interferences. This is a pseudo-Class III malocclusion. In these cases, it is important to establish the inter-occlusal re- lationship with the teeth in the retruded contact position. In this paper, the surgical or- thodontic treatment of a young adult patient with a Class III malocclusion is illustrated Diagnostic and Etiology The patient was a 28 year-old man who had a Class III facial type and slight crowding with a complete Class III relationship. His chief complaint was an un- esthetic facial and un-even bite. His medical history showed no contraindication for orthodontic therapy and orthognathic treat- ment. No one in his direct family had a skeletal Class III features. The pretreatment extra-oral photographs showed symmet- ric facial structures (Fig 1). The patient had a concave profile, a decreased nasolabial angle and a protusive lower lip. The intra-oral photographs (Fig 2) showed a Class III occlusion on each side with an anterior crossbite and without apparent crowding. Overjet was -2.0 mm, and overbite was -3,5 mm. His maxillary anterior teeth were prognathic, with inadequate dis- play when smiling. The mandibular dental mid- line was deviated 2,5 mm to the right, although the maxillary dental midline was coincident with the facial midline. There were no signs or symp- toms of temporomandibular joint dysfunction. Mandibular movements, such as maximal opening and lateral and ante- rior displacement were within normal limits. No deviation and pain were discovered during the border movement of the mandi- ble. A cephalogram and a panoramic radiograph were taken before treatment. The cephalometric analysis and its tracing showed that the mandible protruded relative to the cranial base (SNB angle, 82; ANB angle -2). The panoramic radiograph showed > Page 25