chapter14,牙周牙髓联合病变Stillwatersrundeep.流静水深流静水深,人静心深人静心深Wherethereislife,thereishope。有生命必有希望。有生命必有希望根管侧支根管侧支Lateral root canal或副根管或副根管Accessory canal根尖1/3处最多根分叉区20-60%有 The pulp was non-vital and the tooth was endodontically treated. After prosthetic therapy The pulp was non-vital and the tooth was endodontically treated. After prosthetic therapy (c), the 2 -year follow-up radiograph in (d) shows bone fill in the previous angular bony defect, whereas the marginal bone remains at the same level. On careful examination one can see that a lateral canal communicating with the lateral bone defect was filled. 牙本质小管牙本质小管 Dentinal tubules解剖异常解剖异常 Anatomical abnormalities 腭侧沟 牙根外吸收 根裂14-2 牙周牙周-牙髓联合病变的临床类型牙髓联合病变的临床类型 Clinical Patterns of Periodontal-Endodontic Combined Lesions1，根尖感染经牙周组织途径排除，有人称之为逆行性牙根尖感染经牙周组织途径排除，有人称之为逆行性牙周炎周炎 (retrograde periodontitis)牙髓根尖周病对牙周组织的影响牙髓根尖周病对牙周组织的影响 influence of endodontic lesions on the periodontium根尖脓肿沿牙周的可能排脓途径Schematic illustration demonstrating possible pathways for drainage of a periapical abscess into the gingival sulcus/pocket. (a) periodontal ligament fistulation. (b) extraosseous fistulationperiodontal ligament fistulation.此型在临床上易被误诊为牙周脓肿特点：特点：死髓牙 窄而深的牙周袋，无明显的牙槽嵴吸收 only a narrow opening of the fistula into the gingival sulcus/pocket and may not be detected unless careful probing of the sulcus is carried out at multiple sites.邻牙一般无严重的牙周炎 X片显示烧杯型或日晕型病变 after 18 M In multirooted teeth a periodontal ligament fistulation can drain off into the furcation area，牙髓治疗过程中或治疗后造成的牙周病变，牙髓治疗过程中或治疗后造成的牙周病变根管侧穿，髓室底穿，髓室或根管内的药物（砷戊二醛塑化液干髓剂等）During endodontic treatment, and in conjunction with preparation of root canals for the insertion of posts, instrumentation can accidentally cause perforation of the root and wounding of the periodontal ligamentAngular bone defect at the distal root surface of a mandibular premolar (arrows). The root is perforated. Conceivably, this occurred in conjunction withpreparation of the root canal for a post and core. Clinicalsymptoms included drainage of pus from the pocket and increased tooth mobility. The tooth was extracted.Perforation of the pulpal floor of the mandibular first molar occurred in conjunction with a search for root canal openings (a). The perforation was immediately sealed with gutta-percha (b). One month after treatment a slight radiolucency appeared at the perforation site (arrow) in the periodontium (c). After an observation period of 2 years, normal periodontal conditions were re-established both clinically and radiographicallyRCT治疗后可发生牙根纵裂治疗后可发生牙根纵裂: 主要由于扩根过度主要由于扩根过度,桩核不当桩核不当, 过大合力过大合力等等共同特点共同特点:牙髓无活力牙髓无活力病变局限于单个牙，局限于患牙的局部病变局限于单个牙，局限于患牙的局部病变呈烧杯状，病变呈烧杯状，邻牙基本正常邻牙基本正常Vertical root fracture结局结局: Vertical root fractures that involve the gingival sulcus/pocket area usually have a hopeless prognosis due to continuous bacterial invasion of the fracture space from the oral environment.External Root resorption Surface resorptionA surface resorption is initiated subsequent to injury of the cementoblastic cell layer. Osteoclasts are attracted by substances from the damaged tissue on the denuded root surface and resorb the hard tissueThese resorptions may be caused by a localizedinjury in conjunction with external trauma (Andreasen1981) and by trauma from occlusion. Resorptionmay also result from excessive orthodontic forces.This type of resorption is common, self-limiting and reversibleReplacement resorptionThis type of resorptive process results in a replacement of the dental hard tissues by bone, hence the name Replacement resorption and ankylosis are often used as synonyms.Clinically, ankylosis is diagnosed by absent tooth mobility and by a percussion tone that is higher than in a normal toothExternal inflammatory resorptionThe term external inflammatory resorption suggests the presence of an inflammatory lesion in the periodontal tissues adjacent to a resorptive process牙周病变对牙髓的影响牙周病变对牙髓的影响 Iinfluence of periodontal disease on the pulp1, 逆行性牙髓炎 Retrospective pulpitis 2，长期存在的牙周病变：轻者 修复性牙本质 重者 炎症 变性 钙化 坏死 因牙周炎拔除的无龋牙，64%有牙髓的炎症或坏 死，与PD成正比 3，牙周治疗对牙髓的影响 Influence of periodontal treatment measures on the pulp14-3 治疗原则治疗原则 Treatment strategies for vombined endodontic and periodontal lesions确定原发原因。 联合病变的预后往往取决于牙周病损的预后，牙周破坏不严重，牙齿不松动，预后较好1，由牙髓根尖病变引起的牙周病变 清除感染源的牙髓消除袋内感染完善RCTFirst observe the result of this therapy and institute periodontal therapy later if necessary2，逆行性牙髓炎主要看患牙能否保留牙髓初步治疗，如病变可以控制，牙髓牙周同时治疗