放疗和高压氧辅助治疗对狗下颌纯钛种植体周围骨组织沉积率的影响

The effect of radiation and HBO(hyperbaric oxygen)treatment on bone mineralization rate around implants in irradiated dog mandibles

目的:观察放疗和高压氧(hyperbaric oxygen,HBO)辅助治疗对狗下颌纯钛种植体周围骨组织沉积率影响。方法:8只成年雄性杂种狗,拔除双侧下颌第三、第四前磨牙和第一磨牙,形成无牙区。拔牙后3个月,用电子直线加速器照射一侧下颌无牙区,单一剂量15Gy。另一侧不接受照射,作为对照。放疗后3个月,狗双侧下颌无牙区植入纯钛种植体各4枚,其中2枚种植体在局部使用骨形成蛋白(bone morphogenetic protein,BMP)与透明质酸钠的复合物。以四环素和二甲酚橙作为荧光标记物,自种植体植入术第一天起注射。放疗后2个月,将8只狗随机分为2组,每组4只。其中1组在种植术前后接受HBO辅助治疗。种植术后1.5个月和3个月分别处死4只动物取材。结果:在1.5个月取材组,沉积率在放疗与非放疗间差别明显(P=0.041<0.05);在HBO辅助治疗与无HBO辅助治疗组间有差别(沉积率2P=0.015<0.05;沉积率3P=0.041<0.05)。在3个月取材组,沉积率在HBO辅助治疗与无HBO辅助治疗组间统计学上有明显差别(P=0.002<0.01)。结论:放疗可以降低种植体周围骨组织的骨沉积率,HBO辅助治疗可以影响放疗后狗下颌种植体周围骨组织的骨沉积率。

Objective： To observe the effect of radiation and HBO（hyperbaric oxygen）treatment on bone mineralization rate around implants in irradiated dog mandibles. Methods： Eight dogs were divided into two groups. One side of each mandible was irradiated with a single 15-Gy dose. The other side served as control. Three months after irradiation, four titanium implants were inserted in each side of the mandible. Two of them were placed with the mixture of rhBMP-2 and hyaluronan.Tetracycline and xylenol orange as fluorescence label were injected in dogs after implants inserted. After another two months, the dogs were divided into two groups. One group received the adjunctive hyperbaric oxygen（HBO） therapy before and after implants insertion. The other group did not .The dogs were sacrificed at 1.5 and 3 months after implants were inserted. Results： In 1.5-month-after-implant groups, bone mineralization rate-1 was obviously lower in the irradiated sides than that in the control sides（P=0.041〈0.05）. Bone mineralization rate-2 and 3 were significantly higher after HBO adjunctive therapy（Bone mineralization rate-2 P=0.015〈0.05; Bone mineralization rate-3 P=0.041〈0.05）. In 3-month-after-implant groups, only bone mineralization rate-2 was obviously increased after HBO adjunctive therapy（P= 0.002〈0.01）. Conclusion： Radiation can decrease the bone mineralization rate around implants in irradiated dog mandibles. HBO adjunctive therapy can improve the bone mineralization rate around implants in irradiated dog mandibles.