치경부 굴곡파절의 형태학적 특성 분석 및 치주낭 깊이와의 연관성 평가 = Morphologic Analysis of Abfraction and Evaluation of Its Association with Probing Depth

다국어 초록 (Multilingual Abstract)

This study aimed to quantitatively evaluate the three-dimensional morphologic characteristics of abfraction lesions using STL-based geometric analysis and to assess the association between abfraction and probing depth (PD), while accounting for the repeated-measures structure of the data.
For the morphologic analysis, 77 abfraction lesions on maxillary and mandibular first and second premolars were analyzed using digital intraoral scan data. Four reference points were defined on the cross-sectional view of each lesion, and OC length, DH depth, angle ODC, and HL ratio were calculated. Lesion orientation was classified according to the position of the deepest point relative to the OC line segment, and lesions were categorized into shallow, moderate, and deep types based on HL ratio.
For the periodontal analysis, 327 permanent teeth and 981 buccal measurement sites from 31 patients were included. Teeth diagnosed with periodontitis or gingivitis, as well as teeth showing clinical signs of gingival inflammation, were excluded to minimize the influence of inflammatory periodontal conditions. PD was measured at the buccal mesial, central, and distal sites. The association between abfraction and PD was analyzed using generalized estimating equations (GEE).
In the morphologic analysis, OC length was positively correlated with DH depth, whereas DH depth was negatively correlated with angle ODC. Mandibular lesions showed greater OC length than maxillary lesions, and second premolars exhibited greater DH depth, smaller angle ODC, and higher HL ratio than first premolars. Root-oriented lesions and moderate-type lesions were the most frequent, but their distributions did not differ significantly according to jaw or tooth type.
In the periodontal analysis, unadjusted mean PD showed minimal difference between teeth with and without abfraction. However, after adjustment for covariates and repeated-measures structure, abfraction was significantly associated with increased PD. This association was significant in the mandible, and a significant interaction was observed between abfraction and jaw. Among teeth with abfraction, most subgroups showed no significant site-specific differences in PD, except for the mandibular posterior subgroup, in which the central site showed significantly greater PD than the mesial site.
Within the limitations of this cross-sectional study, the three-dimensional morphologic features of abfraction lesions were partially interrelated. Abfraction was also significantly associated with increased PD in the adjusted GEE analysis. These findings suggest that abfraction should be evaluated in relation to both lesion morphology and associated periodontal status.

목차 (Table of Contents)

• Ⅰ. 서론 1
• Ⅱ. 연구 대상 및 방법 3
• Ⅲ. 연구 결과 9
• Ⅳ. 총괄 및 고찰 20
• Ⅴ. 결론 25
• 참고 문헌 26