乳歯列、混合歯列および永久歯列における咀嚼側嗜好とう蝕の関連性

Association between Chewing Side Preference and Dental Caries among Deciduous, Mixed and Permanent Dentition.

抄録

はじめに:

咀嚼側嗜好（CSP）とは、咀嚼が専ら／一貫して、あるいは優位に同じ側の顎で認識される場合に生じると言われている。咀嚼側嗜好は、視覚による直接法と、シネマトグラフ、キネトグラフ、コンピュータ筋電図などの電気プログラムによる間接法で評価することができる。

INTRODUCTION: Chewing Side Preference (CSP) is said to occur when mastication is recognized exclusively/consistently or predominantly on the same side of the jaw. It can be assessed by using the direct method - visual observation and indirect methods by electric programs, such as cinematography, kinetography and computerized electromyography.

研究の目的:

本研究は、乳歯、混合歯、永久歯におけるCSPの有病率を評価し、う蝕との関連性を検討することを目的とした。

AIM: The present study was aimed at evaluating the prevalence of CSP in deciduous, mixed and permanent dentitions and relating its association with dental caries.

材料と方法:

3 歳から 18 歳の就学児童 240 名を乳歯列期、混合歯列期、永久歯列期の 3 群に無作為に振り分け、横断的観察研究 を行った。CSPの有無は、ガム（トライデント・シュガーレス）を噛んでもらうという直接的な方法で判定した。CSPの比較にはMann Whitney U-testを用い，また，男女間の比較にも用いた．Spearmanの相関係数は、3つの研究グループ間およびグループ間のCSPとう蝕の相関に使用された。

MATERIALS AND METHODS: In a cross-sectional observational study, 240 school going children aged 3 to 18years were randomly allocated to three experimental groups according to the deciduous dentition, mixed dentition and permanent dentition period. The existence of a CSP was determined using a direct method by asking the children to chew on a piece of gum (trident sugarless). The Mann Whitney U-test was used to compare the CSP and also among the boys and girls. The Spearman's Correlation Coefficient was used to correlate CSP and dental caries among the three study groups and also among the groups.

結果:

CSPは，乳歯列，混合歯列，永久歯列のそれぞれ69％，83％，76％の小児に認められた（p＞0.05）．また，3群間でCSPの有無とう蝕の有無に統計学的に有意な関連は認められなかった．

RESULTS: CSP was observed in 69%, 83% and 76% of children with primary, mixed and permanent dentition respectively (p>0.05). There was no statistically significant association between the presence of CSP and dental caries among the three study groups.

結論:

CSP の有無と性別，CSP の有無とう蝕の有無には相関がない，あるいは弱い相関が認められた．

CONCLUSION: There was a weak or no correlation between gender and distribution of CSP and between presence of CSP and dental caries.