本文基于牙周的观点,讨论了覆盖义齿的适应征和禁忌征、基牙的选择和预备及修复前后的牙周治疗。覆盖义齿适用于余留牙不能再支持可摘局部义齿或固定义齿者。因牙丧失后,下颌骨吸收比上颌多,故它更适于下颌弓。Tallgren观察到戴义齿后7年中,下颌牙槽嵴高度的降低是上颌的4倍多。Crum等测量了两组病人牙槽骨垂直高度的降低:一组用常规上下颌义齿,另一组为常规上颌义齿和下颌覆盖义齿。5年后,发现下颌骨垂直高度的吸收,常规义齿组是覆盖义齿组的8倍多,而上颌两组类似。Ⅲ类错(牙合)或仅有下前牙余留时,上前牙区(牙合)力较大,宜选用覆盖义齿。覆盖义 Based on the periodontal view, this article discusses the indications and contraindications of overdenture, choice and preparation of abutments and periodontal treatment before and after repair. Overdenture for residual teeth can no longer support the removable partial denture or fixed denture. After loss of teeth, the mandible absorbs more than the maxillary, so it is more suitable for the mandibular arch. In the seven years after Tallgren observed the denture, the height of the mandibular alveolar ridge decreased more than four times that of the maxillary. Crum et al. Measured the reduction in vertical height of the alveolar bone in both groups: one with a conventional maxillary denture and the other with a conventional maxillary dentition and a mandibular overdenture. Five years later, the vertical height of the mandible was found to be more than eight times greater than in the conventional denture group, while the maxillary and mandibular groups were similar. Ⅲ class of malocclusion (occlusion) or only the remaining anterior teeth, the anterior teeth (occlusal) force larger, should use overdenture. Cover justice