However, preparing the restseat on the lingual surface of a mandibular canine risks perforating the enamel.
然而，准备其余席位的舌表面的风险射孔犬下颌骨的珐琅质。
2
An alternative rest-seat preparation, on the marginal ridge of the canine crown, conserves tooth structure and provides a restseat of adequate length and depth to ensure support for a cast framework.