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目的:通过显微CT（micro-CT）和组织形态学分析探讨氟化猪骨羟基磷灰石（fluorinated porcine hydroxyapatite，FPHA）修复比格犬下颌种植体颊侧开裂型骨缺损的效果。方法:通过随机数字表法将6只雄性比格犬随机分为两个时间点（骨增量术后4和12周）处理，每个时间点3只。拔除犬下颌双侧第二前磨牙至第二磨牙，术后12周下颌骨每侧制备4个种植窝洞，在窝洞颊侧骨壁制备开裂型骨缺损。将48个缺损位点通过随机数字表法随机分为空白对照组、脱蛋白牛骨基质（deproteinized bovine bone mineral，DBBM）组、猪骨羟基磷灰石（porcine hydroxyapatite，PHA）组和FPHA组（每组每个时间点6个位点）。种植体植入后，在缺损区分别植入相应骨替代材料，空白对照组不放置任何材料，各组均覆盖可吸收胶原膜后无张力缝合创口。分别于骨增量术后4、12周处死动物，获取种植位点标本，通过micro-CT分析获得新生骨体积分数（bone volume fraction，BV/TV）和骨小梁分离度（bone trabecular separation degree，Tb.Sp），进行不脱钙硬组织切片，通过组织形态学分析评价材料对种植体颊侧开裂型骨缺损的修复能力。结果:micro-CT结果显示，术后4周DBBM、PHA与FPHA均能成功维持缺损区牙槽骨外形轮廓，空白对照组缺损区牙槽骨轮廓塌陷；FPHA组BV/TV［（24.77±2.20）%］显著大于PHA组［（16.89±1.70）%］和DBBM组［（15.68±3.15）%］（n P<0.05）；FPHA组Tb.Sp（0.70±0.07）显著小于DBBM组（1.03±0.19）（n P0.05）。组织形态学结果显示，术后4周骨缺损中央区FPHA组材料颗粒周围新生骨含量和成熟度高于PHA和DBBM组，4组骨缺损区均可见新生骨与种植体形成骨结合。术后12周DBBM、PHA和FPHA组材料颗粒被大量成熟的新生骨包绕。n 结论:FPHA可在引导骨再生的早期有效促进种植体周骨缺损的修复。“,”Objective:To evaluate the effects of fluorinated porcine hydroxyapatite (FPHA) on guided bone regeneration of peri-implant buccal bone defects in canine mandible.Methods:Six male beagle dogs were randomly divided into two groups with different time points (4 weeks and 12 weeks after implants placement), with 3 dogs in each group. Bilateral mandibular second premolars, first molars, and second molars in each dog were extracted. The wounds were allowed to heal for 12 weeks. For each dog, four implant beds were prepared in each side and standardized peri-implant buccal bone defect was created at each implant site. After implants placement, the defect sites were randomly allocated in a split-mouth design to blank control group, deproteinized bovine bone mineral (DBBM), the porcine hydroxyapatite (PHA), FPHA and covered with collagen membranes. The animals were sacrificed 4 or 12 weeks after the surgery. Biopsies of the implant sites were obtained for micro-CT evaluation [bone volume fraction (BV/TV) and bone trabecular separation degree (Tb.Sp)] and histological analysis.Results:Micro-CT results showed that 4 weeks after implants placement, PHA, FPHA and DBBM successfully maintained the contour of alveolar ridge at the buccal aspect of the implants, while the contour of alveolar ridge collapsed in the blank control group. BV/TV in the FPHA group [(24.77±2.20) %] was significantly higher than that in the PHA group [(16.89±1.70)%] and DBBM group [(15.68±3.15)%] (n P<0.05). Tb.Sp in the FPHA group (0.70±0.07) was significantly lower than that in the DBBM group (1.03±0.19) (n P<0.05). Twelve weeks after implants placement, the alveolar ridge contour of the grafted sites in PHA, FPHA and DBBM group remained stable. The alveolar ridge of the blank control group was still collapsed. There was no significant difference in BV/TV and Tb.Sp between PHA group, FPHA group and DBBM group. The histomorphological analysis showed that 4 weeks after implants placement, in the central area of the defect, the amount and maturity of new bone (NB) around the material particles in FPHA group was higher than that in PHA group and DBBM group. Osseointegration could be observed between the NB and implant surface in all the four groups. Twelve weeks after implants placement, the material particles were surrounded by a large number of mature NB in PHA, FPHA and DBBM group.n Conclusions:The incorporation of fluoride ion into PHA could effectively promote the repair of peri-implant bone defects in the early stage of guided bone regeneration.