Ross I F, Evanchik P A
J Periodontol. 1981 Nov;52(11):663-7. doi: 10.1902/jop.1981.52.11.663.
The study was done to determine the incidence and distribution of root fusion in 1340 maxillary and mandibular molars in 170 patients. A second objective was to determine whether root fusion of molars is sex-linked. A substantial percentage, 29% of all molars, had fused roots. Root fusion was found more frequently in maxillary than mandibular molars, 35% to 24%, and it occurred in many patients, rather than being limited to a few. Root fusion was most common in third molars, followed by second molars, in both jaws. It occurred in almost equal numbers in corresponding molars of opposite sides, approaching bilateral symmetry. The proportion of molars with root fusion was approximately 5% greater in females than in males, and about 13% more females had molar root fusion than males.
本研究旨在确定170例患者的1340颗上颌和下颌磨牙牙根融合的发生率及分布情况。第二个目的是确定磨牙牙根融合是否与性别有关。在所有磨牙中，有相当比例（29%）出现了牙根融合。上颌磨牙的牙根融合比下颌磨牙更常见，分别为35%和24%，并且在许多患者中都有发生，并非局限于少数患者。牙根融合在第三磨牙中最为常见，其次是第二磨牙，在上颌和下颌均如此。两侧相应磨牙的牙根融合数量几乎相等，接近双侧对称。女性磨牙牙根融合的比例比男性大约高5%，有磨牙牙根融合的女性比男性多约13%。
