【作者】 何金梅；

【导师】 边专；

【作者基本信息】 武汉大学 ， 口腔临床医学， 2004， 博士

【摘要】 在牙髓病的治疗中，根管阻塞是经常遇到的较为棘手的问题。造成根管阻塞的原因主要有牙髓钙化、根管内充填物和异物等。目前大多数研究主要集中在根管治疗失败后根管的重新疏通，而塑化治疗失败后根管再治疗和钙化根管的研究较少。因此，探讨有效地疏通塑化治疗根管和钙化根管的方法，将有助于提高根管治疗的成功率。 1 塑化治疗失败牙齿的临床研究 研究塑化治疗失败的牙齿去除根管内塑化物，疏通根管的方法，探讨影响再治疗的因素。收集有塑化治疗史而需要重新根管治疗的牙齿56例，记录临床症状和牙位，拍初始X线片并记录根尖情况。进行再治疗前，仔细阅读X线片，明确根管的弯曲角度和部位，如果根管有弯曲，则在疏通前G钻1～3#首先磨除根管口的塑化物，敞开根管上段，减小或消除弯曲。去除冠部充填物，显微镜下牙髓探针探察根管口。15# K锉探查根管内充填物的固化情况，如根管锉能进入根管，根管通畅，用#15 K锉去除根管内的酚醛树脂。如根管不通，确定根管口后用小球钻磨除根管口的充填物，G钻1～3#敞开根管上段，小号LN或超声根管锉沿着酚醛树脂的痕迹去除根管内的充填物。如果是弯曲根管，疏通至根管中份时，换用手用器械疏通根管，使用15# K锉运用凿的方法，上下摆动幅度为1mm左右疏通根管，直到到达根尖，2.5％NaOCl冲洗根管。治疗过程中，及时拍摄x线片观察和调整根管疏通方向。根管壁光滑，锉上没有塑化物，则为塑化物去除干净。疏通根管，并拍X线片确定是否达工作长度。如不能到根尖，则认为根管不通。采用混合根管预备技术重新预备根管，冷牙胶侧方加压法充填根管，牙冠修复，并定期复查。记录根管疏通，器械折断，侧穿和术后疼痛的情况，统计分析影响疏通的原因。结果42例患牙成功进行再治疗，14例患牙失败，其中3例出现侧穿，1例器械折断。16例患牙出现术后疼痛。所有前磨牙都治疗成功。有根尖暗影患牙根管疏通率显著高于无根尖暗影牙齿(p＜0.05)。初次治疗史时间对根管疏通所需的就诊次数有显著影响。术后疼痛的发生与根尖病变和术前症状有显著性联系(p＜0.05)。表明塑化治疗的牙齿再治疗时，初次治疗史的时间、根尖病变情况和牙位对根管疏通有显著性地影响。2钙化根管的临床研究 通过研究钙化根管的临床治疗，探讨根管钙化的原因和治疗方法，保存患牙。选择根管钙化不通的病例35例，询问治疗史、外伤史及其他病史，拍不同角度的牙片，分析钙化程度和部位，记录患牙牙冠，根尖和牙周情况，制定治疗计划。常规开髓，髓腔钙化时，参考X光片，慢速球钻修整洞型，使髓腔完全暴露，至正常髓腔位置。2.5%NaOCI冲洗髓腔，显微镜下牙髓探针检查髓腔，观察牙本质色泽和质地的不同，寻找根管口位置。发现细小的根管口时，用06#或08#SSK锉直接疏通根管。有明显钙化的痕迹如颜色或质地的改变时，用超声工作尖和LN球钻沿钙化痕迹去除钙化牙髓组织，牙髓探针，OS#K锉探查根管并疏通。如没有明显的钙化痕迹，则用LN球钻从髓腔中央沿着牙齿长轴，慢慢地向根尖方向磨去钙化物，17%EDTA和2.5%NaOCI冲洗，随时用牙髓探针，06#或OS#K锉探查根管口，疏通根管。必要时拍摄不同角度X线片检查和调整疏通的方向和深度。如果髓腔和根管内有充填物，则先去除充填物。疏通根管后，常规逐步后退法根管预备消毒，冷牙胶侧方加压法充填根管，定期复查。27例患牙根管成功地疏通，8例患牙治疗失败。18例有过外伤史，占51.4%。外伤是引起前牙根管钙化的主要原因，其次为牙髓治疗。根管钙化程度对根管的疏通有显著性影响。在治疗根管钙化的病例时，需要一些特殊的设备、器械和试剂;而且要求操作者有一定的经验，细心和丰富的知识。不同角度的X线片为临床治疗钙化根管提供了很大的帮助。更多还原

【Abstract】 Blocked canals were often met in the clinic and the treatment was very difficult and time-consuming, sometimes accompanying with the sequela of transportation and perforation. The common reasons of block include calcified canals, obturation and foreign materials and so on. Many studies were made on the removal of gutta-percha and metal obstacles. But as for the resinifying treated teeth and calcified canals there was seldom reported. The purposes of this thesis were to investigate the retreatment of the resinifying treated teeth and the calcified pulp teeth and analyze factors affecting the success of retreatment.The clinic study of the retreatment of failed resinifying treated teeth To study how to remove the FR resin from the resinifying treated teeth and renegotiate the canals, analyze the factors affecting negotiation. Collecting 56 resinifying teeth that need retreatment, the symptoms and radiography outcome were recorded. Before the retreatment, the X-ray film was taken and read to affirm the direction and position of the curvature. If the canals were curved, the coronal parts of the canals were flared-up with G-burs to reduce the curvature before the negotiation. After removing the coronal obturation, the orifices were located under the dental microscopy. The 15# K-file was used to explore the degree of the polymerized FR resin. If the 15# K-file could deepen into the canals, it was proven the FR resin was partly polymerized and 15 K-file was used to remove the FR resin, then 20#,25#,30#,35# files were used in turn. The canals were irrigated with 2.5% NaOCl when changing the file. If the 15 H-file could not deepen into the canals, the LN was used to remove the FR resin from the orifices and then rechanged to ultrasonic files along the trace of FR resin to remove the resin. If the canals were curved the FR resin was removed to the middle 1/3 with ultrasonic files, 15# or 10# K-file was rechanged to remove the FR resin with picking or stroking action until to the apex. At the meanwhile the canals were irrigated with 2.5% NaOCl. During the negotiation, X-ray films were taken to observe and adjust the direction of negotiation when necessary. It was thought as FR resin complete removal that the canals were smooth and the file was no FR resin. The working length was determined with the X-ray film.If the file could not reach the apex, it was thought as failure. After negotiation, the canals were reinstrumented with hybrid preparation technique, filled with cold gutta-percha by lateral condensation technique. The tooth was restored and recalled periodically. During the retreatment the negotiated canals, broken files, perforation and the incidence of postoperation pain were recorded. The results were analyzed statistically. It was found that 42 cases were successfully retreated and 14 cases failed including 3 cases perforated, 1 case file broken. 16 cases had postoperative pain. All of the premolars were successfully retreated. The success rate of cases with apical radiolucent area was significantly higher than that of no apical radiolucency (P<0.05). The interval length of two treatments had significant effect on the outcome of negotiation (P<0.05).There was significant difference between the incidence of postoperative pain and apical lesion (P<0.05). The results showed that the length of two-treatment interval, apical lesion and teeth positions had significant effects on the success rate of the retreatment.The treatment of calcified canalsThe aim of this study was to investigate how to treat the cases with calcified canals and what affect the treatment outcome. 35 teeth with calcified canals, which need root canal treatment, were collected. The present and past histories of the teeth were collected and the clinic examination and periodontal and apical status were recorded. The X-ray films with different angle were taken. The calcified degree and position was determined. The treatment plan was made. When treatment the pulp was accessed at first. If the pulp chamber was also calcified, the pulp was obtained更多还原