[Soft and hard tissue changes after maxillary protraction with skeletal anchorage implant in treatment of Class III malocclusion].

OBJECTIVE

To evaluate the soft profile and hard tissue changes after maxillary protraction with skeletal anchorage implant in treatment of Class III malocclusion during growth period.

METHODS

18 patients with skeletal Class III malocclusion were treated with maxillary protraction for about 9 months, (3.5 +/- 0.1) N, with skeletal anchorage implant and face mask. Cephalometric records were analyzed to assess the changes of maxillo-facial structure of the hard and soft tissue before and after treatment.

RESULTS

All patients' Class III profiles were corrected. Maxillary growth increased, chin clockwise rotated, facial convexity angle increased, lower lip protrusion decreased. Facial vertical height ratio, nasolabial angle, upper lip protrusion and mentolabial sulcus changed unconspicuously. Upper incisors kept in sites, lower incisor upright, maxilla moved forwards. SNA, ANB significantly increased. SNB decreased and the mandible clockwise rotated.

CONCLUSION

The maxilla is effectively protracted without significant rotation by using skeletal anchorage implant. The undesired effects of conventional protraction therapies, such as labial tilt of upper anterior teeth and extrusion of the maxillary molars, are reduced or eliminated with skeletal anchorage implant. These effects can conspicuously correct profiles of the patients with skeletal Class III malocclusion, make the profile more harmonious and aesthetic.