低出生体重児における下顎中切歯の晩期破折：コホート研究

Late Eruption of Mandibular Central Incisor in Small for-Gestational-Age Infants: A Cohort Study.

抄録

早産で低体重（PLBW）で出生した乳児における下顎第一中切歯の萌出の年代と、出生時の妊娠年齢（GA）に対する体重/体長比、個体特性、出生時の入院との関連を評価すること。 ブラジルのベロオリゾンテにある大学病院の集学的レファレンスセンターで、46人の乳児のコホートを追跡調査した。組み入れ基準は、低出生体重児/超低出生体重児/極低出生体重児の早産児で、生後4ヵ月以上の乳児とした。口腔臨床検査は、第一下顎中切歯の萌出の年代を確認するために、各検査の間隔を1ヵ月とし、計8ヵ月間、校正された歯科医によって実施された。養育者は社会人口統計学的質問票および健康質問票に記入した。新生児の入院に関するデータは医療記録から収集した。データはKaplan-Meier法と対数順位検定で分析し、二変量解析はMann-Whitney法とKruskal-Wallis検定で行った（<0.05）。 下中切歯萌出時期の平均年齢は男女とも11ヵ月であった。歯の萌出と子どもの入院や個人の特性との間に関連は認められなかった（＞0.05）。妊娠月齢が大きい乳幼児（9.3±1.41ヵ月）は、妊娠月齢が小さい乳幼児（13.6±3.29ヵ月）よりも歯の萌出が早かった（<0.05）。早産で低体重で出生した乳児の最初の乳歯萌出の可能性が最も高い年齢は11ヵ月であり，個人差や出生時の入院の影響は認められなかった．低体重児は低体重児に比べて歯の萌出が遅れていた。

To evaluate the chronology of the eruption of primary mandibular central incisors in infants born preterm and with low weight (PLBW) and its association with weight/length ratio for gestational age (GA) at birth, individual characteristics and hospitalization at birth. A cohort of 46 infants was followed at a multidisciplinary reference center at a university hospital in Belo Horizonte, Brazil. The inclusion criteria were infants born preterm with low/very low/extreme low birth weight and at least four months of age. Oral clinical examinations were carried out by a calibrated dentist for a total of eight months, with a one-month interval between each examination, to verify the chrono- logy of eruption of the primary mandibular central incisors. Caregivers completed a sociodemographic and health questionnaire. Data on neonatal hospitalization were collected from medical records. Data were analyzed with the Kaplan-Meier method and log rank test, and bivariate analysis was done using the Mann-Whitney method and Kruskal-Wallis test ( <0.05). The average age at eruption of primary lower central incisors was 11 months for both sexes. No association was found between tooth eruption and child hospitalization or individual characteristics ( >0.05). Infants large for gestational age had earlier tooth eruption (9.3±1.41 months) than infants small for gestational age (13.6±3.29 months; <0.05). The most likely age for the eruption of the first primary teeth in infants born preterm and with low weight was 11 months, and there was no influence of individual characteristics and hospitalization at birth. Small-for-gestational age infants experienced delayed tooth eruption compared to large-for-GA infants.