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本文对４２０颗上颌第三磨牙面牙尖与牙根关系进行了探讨。结果表明：面牙尖呈四型，依次为三尖型（５２．３８％）、四尖型（３４．５３％）、双尖型（９．５２％）和五尖型（３．５７％）。牙根呈三型，依次为融合根（４８．５７％），双棍（３２．８６％）和三根（１８；５７％）。面牙尖为二尖型和三尖型的上颌第三磨牙，其牙很多为融合根，占６８％，而多根占３２％（其中双根为２５％、三根为７％）；面牙尖为四尖型和五尖型的上颌第三磨牙，其牙根常为多根（双根或三根），占８０％，而融合根仅占２０％。
In this paper, the relationship between the cusp tip and root of 420 maxillary third molars was studied. The results showed that there are four types of cusp tip, which are trilobular type (52.38%), tetrapod type (34.53%), bipolar type (9.52%) and pentapoda type ). Three types of root were found, followed by fusion root (48.57%), double stick (32.86%) and three root (18.57%). The maxillary third molars with apical cusp and apical cusps are 68% of the maxillary teeth, while the majority of the teeth are 32% (25% for double root and 7% for three). The cusp tip For the four-pointed and five-pointed maxillary third molar, the root is often multiple (double root or three root), accounting for 80%, while the fusion root only accounts for 20%.