Abstract: The teeth with severe periodontitis are often accompanied by severe infection and alveolar bone defects，and further physiological absorption and remodeling of the alveolar ridge after tooth extraction，which will increase the difficulty in prosthetically driven implant placement. Especially，the maxillary molar region is close to the maxillary sinus，maxillary sinus floor elevation is usually required to compensate for insufficient vertical bone. This paper presents the clinical outcome of alveolar ridge preservation with flapless techniques in maxillary molar extrication sockets suffering from severe periodontitis. Atraumatic extraction and flapless techniques for alveolar ridge preservation were used to preserve the extraction socket，which effectively reduced bone absorption and achieved the preservation and reconstruction of alveolar ridge，providing a good three-dimensional condition of bone tissue for implant placement. This method advances the process of bone augmentation in the maxillary molar region and simplifies the complexity of implant treatment，which is worthy of clinical application.

Key words: maxillary molar, severe periodontitis, ridge preservation, dental implantation

摘要： 罹患重度牙周炎的患牙常伴有严重的感染和牙槽骨破坏，而且拔牙后牙槽窝在愈合过程中进一步骨吸收和改建，增加了后期以修复为导向的种植治疗难度。在上颌磨牙区因毗邻上颌窦，种植治疗常需要进行上颌窦提升术来弥补垂直骨量不足。文章展示了1例罹患重度牙周炎的上颌磨牙，通过微创拔牙后彻底清除牙槽窝感染，结合微翻瓣牙槽嵴保存术，有效减少牙槽窝愈合过程中的骨吸收，实现牙槽嵴的保存和重建，为后期种植修复提供了良好的硬组织三维条件。这一方法将上颌磨牙区骨增量术前移，简化了后续种植治疗的复杂性，值得临床推广应用。

关键词: 上颌磨牙, 重度牙周炎, 牙槽嵴保存, 牙种植