6～14歳の小児における上顎犬歯、側切歯、第一小臼歯の正常な発音前傾斜

Normal pre-eruptive inclinations of maxillary canine, lateral incisor, and first premolar in children aged 6-14 years.

抄録

背景:

上顎犬歯はⅢ大臼歯に次いで2番目に多く咬合する歯である。第一小臼歯の発育前早期の傾斜変化と犬歯の傾斜との関連変化は、上顎犬歯の運命を予測する重要な因子である。そこで、6～14歳の小児の上顎永久犬歯、第一小臼歯、側切歯の正常な発育前中切歯傾斜をオルソパントモグラムを用いて評価するための横断的研究を計画した。

BACKGROUND: Maxillary canine is the second most common tooth that gets impacted after III molars. Early pre-eruptive inclination changes of first premolar and its associative changes with canine inclination are an important factor that predicts the fate of maxillary canines. Hence, a cross-sectional study was planned to evaluate the normal pre-eruptive mesiodistal inclinations of maxillary permanent canine, first premolar, and lateral incisor in children aged 6-14 years using orthopantomogram.

材料と方法:

参加者は296名であった。各グループは、6～8歳、8～10歳、10～12歳、13～14歳の各年齢グループ37名から構成され、合計で男子148名、女子148名であった。通常の臨床検査が行われ、X線検査のためにオルソパントモグラフが撮影された。これらの参加者全員のオルソパントモグラフが収集された。オルソパントモグラム上で、側切歯の傾斜、犬歯の傾斜、小臼歯の正中線に対する傾斜を測定した。また、犬歯と側切歯、犬歯と第一小臼歯の角度も測定した。また、犬歯と側切歯の動きと犬歯と第一小臼歯の動きの間にピアソン相関を評価した。

MATERIALS AND METHODS: The total number of participants was 296. Each group of boys and girls consisted of 37 participants in each of the age groups 6-8 years, 8-10 years, 10-12 years, and 13-14 years, making up a total of 148 boys and 148 girls. Routine clinical examination was conducted, and orthopantomograph was taken for radiographic examination. Orthopantomographs of all these participants were collected. Inclination of lateral incisor, inclination of canine, and inclination of premolar with midline were measured on the orthopantomogram. Also, the angles between the canine with lateral incisor and canine with first premolar were measured. Pearson correlation was also evaluated between the movement of canine with lateral incisor and canine with first premolar.

結果:

側切歯、犬歯および第一小臼歯と正中線との平均角度をすべて記録した。また、犬歯と側切歯、犬歯と第一小臼歯の角度も記録した。側切歯、犬歯、第一小臼歯の動きは、6歳から12歳まで中程度の相関があった。

RESULTS: All the mean angles related to lateral incisor, canine, and first premolar with midline were recorded. Also, the angles between the canine with lateral incisor and the canine with first premolar were recorded. The movements between lateral incisor, canine, and first premolar were moderately correlated from 6 to 12 years of age.

結論:

犬歯が鼻の下から萌出するまでには、側切歯と第一小臼歯に同期した影響を与える。

CONCLUSION: The eruption of canine from the floor of the nose till it erupts has its synchronized influence on the lateral incisor and the first premolar.