Abstract:

Objective: This study aimed to investigate the therapeutic effect of platelet rich fibrin (PRF) combined with autogenous bone chips promoting the repair of the distal osseous defect of mandibular second molar after impacted third molar tooth extraction. Methods: PRF was prepared by centrifugation of autogenous whole blood. The autogenous bone was obtained from the external oblique line around the extraction area by piezosurgical device and transplanted into the alveolar fossa after extraction of mandibular third molar. Tooth extraction wound was covered with PRF membrane and tightly sutured. PRF plus autogenous bone was set as experimental group, tooth extraction without guide tissue regeneration was set as control group. Cone beam computed tomography(CBCT) was used to evaluate the distal bone regeneration through measuring osseous defect depth (ODD); The severity of postoperative symptoms was evaluated by clinical postoperative sympotom severity scale (PoSSe); The distal probing depth (PD) and attachment level (AL) of mandibular second molar were measured at 3 and 6 months after operation. Results: The depth of bone defect in the experimental group was significantly lower than that in the control group at 3 months and 6 months after operation(P<0.001). At 3 months after operation, the average reduction of ODD was 3.99 mm in the experimental group and 2.77 mm in the control group; compared with the preoperative control group, the postoperative 6 months decreased by 3.47 mm, the experimental group decreased by 4.22 mm (P<0.05). There was no significant difference in the depth of detection and the level of AL between the experimental group and the control group at each time point (P>0.05). In the comparison of PD and AL between the experimental and control group, PD at postoperative 6 months compared to 3 months showed statistical difference (P<0.05). There was no statistical difference in PD and AL at postoperative 6 months compared to preoperative (P>0.05). Compared with the control group, the experimental group may have more postoperative reactions and more postoperative discomfort symptoms, but there was no significantly statistical difference. Conclusions: The clinical and radiological evaluation outcomes suggest that PRF combined with autogenous bone can significantly promote the distal bone repair of the second molar after mandibular third molar extraction.

Key words: autogenous bone, platelet-rich fibrin, periodontal bone loss, impacted tooth extraction

摘要：

目的: 通过将富血小板纤维蛋白（platelet-rich fibrin，PRF）与自体骨混合，研究其对促进下颌阻生第三磨牙拔除后第二磨牙远中牙槽骨骨缺损修复的作用。方法: 采用自体全血离心制备 PRF，利用超声骨刀取自拔牙术区周围外斜线的自体骨，实验组为PRF混合自体骨， 将两者混合置于下颌第三磨牙拔除后的牙槽窝内，随后覆盖PRF膜，严密缝合。对照组为单纯去骨拔牙组。通过锥形束CT（cone beam computed tomography，CBCT）测定骨缺损深度（osseous defect depth，ODD）变化以评价远中骨再生效果；通过临床术后症状严重度评定量表（postoperative sympotom severity scale，PoSSe）评价术后症状的严重程度；测定术后3、6个月时下颌第二磨牙远端探诊深度（probing depth, PD）、附着水平（attachment level，AL）等以评价牙周恢复情况。结果: 实验组和对照组的ODD在术后3、6个月时与术前相比，均显著降低，差异具有统计学意义（P<0.001）。术后3个月相对术前比较，实验组ODD平均减少3.99 mm，对照组平均减少2.77 mm；术后6个月相对术前比较，实验组平均减少4.22 mm，对照组平均减少3.47 mm，差异具有统计学意义（P<0.05）。在各时间点PD、AL的比较中，实验组和对照组的差异无统计学意义（P>0.05），在实验组与对照组PD和AL的比较中，术后6个月相较于术后3个月的PD变化量差异有统计学意义（P<0.05），术后6个月相较于术前，2组PD、AL的变化量无显著差异（P>0.05）。实验组较对照组可能存在术后反应更大、术后的不适症状更多的情况，在感觉、疼痛等方面，实验组相对劣于对照组，但差异无统计学意义。结论: 通过临床与放射学评价证实，PRF联合自体骨对下颌第三磨牙拔除后第二磨牙远中的骨修复有显著促进作用。

关键词: 自体骨, 富血小板纤维蛋白, 骨缺损, 阻生齿拔除