Improvement of chin profile after mandibular setback and reduction genioplasty for correction of prognathism and long chin

Background: This study evaluated the changes in the chin profile after using mandibular setback and vertical chin reduction genioplasty to correct mandibular prognathism associated with a long and flat chin. Methods: Sixteen consecutive patients (6 male and 10 female) underwent surgery at a mean age of 22.6 years (range = 18.2-27.8 years). The evaluation consisted of hard and soft tissue analysis before and after treatment. Results: The results showed that improvement in facial profile, chin contour, and dental occlusion was achieved. After an average of 9.4-mm mandibular setback and 5.1- mm vertical osseous chin reduction, the thickness of soft tissue pogonion was increased by 4.0 mm, the supramentale thickness was increased by 1.8 mm, and lower-lip thickness was increased by 1.6 mm. Thus, the mentolabial fold increased from 3.4 to 4.7 mm and the mentolabial angle decreased from 153.4 to 136.9°. The vertical lip:chin ratio became normal. Conclusion: The results of this study demonstrated that mandibular setback combined with vertical chin reduction genioplasty offers an alternative for the treatment of patients suffering from mandibular prognathism with a long, nonprojecting chin. Level of Evidence IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.