Scheffler Nicole R, Proffit William R, Phillips Ceib
Adjunct associate professor, Department of Orthodontics, School of Dentistry, University of North Carolina, Chapel Hill, NC.
Kenan distinguished professor, Department of Orthodontics, School of Dentistry, University of North Carolina, Chapel Hill, NC.
Am J Orthod Dentofacial Orthop. 2014 Nov;146(5):594-602. doi: 10.1016/j.ajodo.2014.07.020. Epub 2014 Oct 28.
Temporary skeletal anchorage devices now offer the possibility of closing anterior open bites and decreasing anterior face height by intruding maxillary posterior teeth, but data for treatment outcomes are lacking. This article presents outcomes and posttreatment changes for consecutive patients treated with a standardized technique.
The sample included 33 consecutive patients who had intrusion of maxillary posterior teeth with a maxillary occlusal splint and nickel-titanium coil springs to temporary anchorage devices in the zygomatic buttress area, buccal and apical to the maxillary molars. Of this group, 30 had adequate cephalograms available for the period of treatment, 27 had cephalograms including 1-year posttreatment, and 25 had cephalograms from 2 years or longer.
During splint therapy, the mean molar intrusion was 2.3 mm. The mean decrease in anterior face height was 1.6 mm, less than expected because of a 0.6-mm mean eruption of the mandibular molars. During the postintrusion orthodontics, the mean change in maxillary molar position was a 0.2-mm extrusion, and there was a mean 0.5-mm increase in face height. Positive overbite was maintained in all patients, with a slight elongation (<2 mm) of the incisors contributing to this. During the 1 year of posttreatment retention, the mean changes were a further eruption of 0.5 mm of the maxillary molars, whereas the mandibular molars intruded by 0.6 mm, and there was a small decrease in anterior face height. Changes beyond 1 year posttreatment were small and attributable to growth rather than relapse in tooth positions.
Intrusion of the maxillary posterior teeth can give satisfactory correction of moderately severe anterior open bites, but 0.5 to 1.5 mm of reeruption of these teeth is likely to occur. Controlling the vertical position of the mandibular molars so that they do not erupt as the maxillary teeth are intruded is important in obtaining a decrease in face height.
临时骨锚固装置现在为通过压低上颌后牙来关闭前牙开颌和降低前面高提供了可能性，但缺乏治疗结果的数据。本文介绍了采用标准化技术治疗的连续患者的治疗结果和治疗后变化。
样本包括33例连续患者，他们使用上颌咬合板和镍钛螺旋弹簧将上颌后牙压低至颧骨支柱区域、上颌磨牙颊侧和根尖的临时锚固装置。在该组中，30例患者在治疗期间有足够的头颅侧位片，27例患者有包括治疗后1年的头颅侧位片，25例患者有2年或更长时间的头颅侧位片。
在咬合板治疗期间，磨牙平均压低2.3毫米。前面高平均降低1.6毫米，由于下颌磨牙平均萌出0.6毫米，低于预期。在压低后正畸治疗期间，上颌磨牙位置的平均变化是伸长0.2毫米，面高平均增加0.5毫米。所有患者均保持了正覆合，切牙轻微伸长（<2毫米）对此有贡献。在治疗后保持的1年中，平均变化是上颌磨牙进一步萌出0.5毫米，而下颌磨牙压低0.6毫米，前面高略有降低。治疗后1年以上的变化很小，归因于生长而非牙齿位置的复发。
上颌后牙压低可以令人满意地矫正中度严重的前牙开颌，但这些牙齿可能会再次萌出0.5至1.5毫米。控制下颌磨牙的垂直位置，使其在上颌牙齿压低时不萌出，对于降低面高很重要。
