Richman Colin
Medical College of Georgia, Augusta, Georgia, USA.
Compend Contin Educ Dent. 2011 May;32(4):e73-9.
Gingival recession (GR) is a commonly observed dental lesion. The underlying etiology has not been clearly identified, although several theories have been suggested. Tooth crowding or tooth malalignment is also frequently observed, with both conditions appearing to be more prevalent in developed countries with heterogeneous populations.
A total of 25 consecutively treated patients representing 72 teeth and demonstrating facial clinical GR of > 3 mm were examined clinically, photographically, and with 3-dimensional radiology using cone-beam computed tomography. All examined teeth presented with normal interproximal probing depths and attachment levels (less than 4 mm). Tooth position or tooth volume plus the associated adjacent alveolar bone volume and GR were analyzed. This group was further evaluated during periodontal surgery for associated alveolar bone fenestrations or dehiscences.
All teeth demonstrating > 3 mm of GR presented with significantly prominent facial tooth contours and associated alveolar bone dehiscences. Most involved teeth presented with their root structures extending beyond the facial alveolar bony housing (fenestrations). This represents a discrepancy between tooth size and alveolar bone dimensions in the buccolingual, axial, and sagittal orientation. Fewer involved teeth were malpositioned toward the buccal aspect. Both conditions were associated with facial alveolar bone dehiscences and associated GR.
This study suggests tooth volume and/or tooth position within the alveolar bony housing strongly correlate with GR. All nonperiodontitis-involved teeth with GR were associated with either wider teeth or facially aligned teeth. However, it is emphasized that all facially aligned teeth, or "larger" teeth, do not necessarily present with GR. Based on these findings, the radiographic-supporting bone index is proposed. This index should facilitate appropriate evaluation of the alveolar bone supporting the mucogingival complex, both on the facial and lingual aspect of teeth. Further investigations are needed to support these preliminary data.
牙龈退缩（GR）是一种常见的牙齿病变。尽管已经提出了几种理论，但其潜在病因尚未明确。牙齿拥挤或牙齿排列不齐也经常出现，这两种情况在人口多样化的发达国家似乎更为普遍。
对连续治疗的25例患者共72颗牙齿进行了临床、摄影及三维放射学检查，采用锥形束计算机断层扫描。所有检查的牙齿邻面探诊深度和附着水平均正常（小于4mm）。分析牙齿位置或牙齿体积以及相关的相邻牙槽骨体积和牙龈退缩情况。在牙周手术期间对该组患者进行进一步评估，以检查相关的牙槽骨开窗或骨裂。
所有牙龈退缩超过3mm的牙齿均表现出明显突出的面部牙齿轮廓和相关的牙槽骨骨裂。大多数受累牙齿的牙根结构延伸至面部牙槽骨包绕之外（开窗）。这代表了牙齿大小与颊舌向、轴向和矢状向牙槽骨尺寸之间的差异。较少受累牙齿向颊侧错位。这两种情况均与面部牙槽骨骨裂和相关的牙龈退缩有关。
本研究表明牙槽骨包绕内的牙齿体积和/或牙齿位置与牙龈退缩密切相关。所有非牙周炎累及的牙龈退缩牙齿均与牙齿较宽或面部排列的牙齿有关。然而，需要强调的是，所有面部排列的牙齿或“较大”的牙齿不一定都会出现牙龈退缩。基于这些发现，提出了影像学支持的骨指数。该指数应有助于对面部和舌侧牙齿的牙槽骨支持龈黏膜复合体进行适当评估。需要进一步的研究来支持这些初步数据。
