日本語AIでPubMedを検索
片側口唇口蓋裂患者における拡大後の上顎歯槽弓の変化の三次元評価
Three-Dimensional Evaluation of Change in Maxillary Alveolar Arch after Expansion in Unilateral Cleft Lip and Palate Patients.
PMID: 32522935 DOI: 10.2209/tdcpublication.2019-0019.
抄録
上顎歯列弓の狭窄は、口唇口蓋裂患者の咬合異常の主な原因である。このような症例では歯列弓が拡大することがあるが、その後の保定期に再発することが多い。本研究では、治療期と保定期後の上顎弓の3次元変化を調べることで、上顎弓の拡大の安定性を検討した。エッジワイズ・アプライアンスとクワッドヘリックス（CLP群）を用いて上顎弓拡大術を受けた片側口唇口蓋裂患者8名（平均年齢12.5歳）の上顎石膏模型を用いて3次元測定を行った。対照群は、片側唇口蓋裂および歯槽膿漏患者8名（平均年齢12.9歳）であった。測定は、治療前、治療後、保存期間中に行われた。CLP群では、第二小臼歯間の歯槽骨と歯列弓に水平方向の再発が認められ、中切歯、側切歯、犬歯の口唇裂側に垂直方向の再発が認められた。再発が認められた部位では、矯正治療前に成長が低下していた。また，拡大の程度と再発との間には相関関係が認められた．以上のことから，矯正治療後の安定性を高めるためには，発達障害が認められた部位での過剰な水平・垂直方向の歯の移動は避けるべきであることが示唆された．
Narrowing of the maxillary dental arch is a major cause of occlusal abnormalities in cleft lip and palate patients. Although the dental arch may be expanded in such cases, relapse will often occur during the subsequent retention period. In this study, the stability of expansion of the maxillary arch was investigated by examining 3-dimensional change in the maxillary arch during the treatment and post-retention periods. Three-dimensional measurements was performed on maxillary plaster models obtained from 8 unilateral cleft lip and palate patients (mean age, 12.5 years) who had undergone maxillary arch expansion using an edgewise appliance and quad helix (CLP group). The controls consisted of 8 unilateral cleft lip and alveolus patients (mean age, 12.9 years). Measurements were made during the pretreatment, post-treatment, and post-retention periods. In the CLP group, horizontal relapse was observed in the alveolar and dental arches between the second premolars, together with vertical relapse on the cleft side of the central incisor, lateral incisor, and canine. The sites where relapse occurred demonstrated decreased growth before orthodontic treatment. A correlation was observed between the extents of expansion and relapse. These findings suggest that excessive horizontal or vertical tooth movement in areas showing developmental failure should be avoided in order to increase stability after orthodontic treatment.