A cone-beam computed tomography-based morphometric comparison of mandibular molars between Han Chinese and Malays
Jacob John1, Wei Cheong Ngeow2, Ting-Chun Shen3
1Department of Restorative Dentistry, Faculty of Dentistry, Universiti of Malaya, Kuala Lumpur, Malaysia.
Journal of dental sciences
|January 26, 2026
まとめ
Malays exhibit significantly higher tooth and root-to-crown ratios (RCR) in mandibular molars compared to Han Chinese. However, Han Chinese show a higher root-to-mandible ratio (R: Mand) at M2 due to shorter mandibular height.
科学分野:
- 人類学; 歯科; 遺伝学
背景:
- 歯および下顎の形態における民族差は重要です。; これらの差異は、臨床実践および人類学研究に影響を与えます。
研究 の 目的:
- 漢民族とマレー人における下顎第一(M1)および第二(M2)大臼歯の歯長と歯根長歯冠長比(RCR)を比較すること。; これらの民族グループにおける顎骨高に対する歯根長の相対比(歯根-顎骨比またはR: Mand)を評価すること。
主な方法:
- 121件のコーンビームCT(CBCT)スキャン(漢民族60件、マレー人61件)を使用しました。; CBCTソフトウェアを使用して、解剖学的および臨床的な歯冠および歯根の長さを測定しました。; 遠心および近心の歯根測定値の平均を使用して、RCRおよびR: Mandを計算しました。
主要な成果:
- マレー人は、M2臨床歯根長歯冠長比(c-RCR)を除き、漢民族よりも有意に高い歯の形態計測値とRCRを示しました。; M1は一般的にM2よりも大きなパラメータを持っていました。; 漢民族は、グループ間でM1の顎骨高が類似しているにもかかわらず、顎骨高が短いため、M2で有意に高いR: Mand(50.69%)を示しました。
結論:
- 漢民族とマレー人の間で観察された形態計測の違いは、遺伝的および/または環境的要因に由来する可能性があります。; これらの違いは、臨床歯科における顔面形態および咬合に影響を与える可能性があります。
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