Humber Craig C, Sándor G K B, Davis Joel M, Peel Sean A F, Brkovic Bozidar M B, Kim Yong Deok, Holmes Howard I, Clokie Cameron M L
Oral and Maxillofacial Surgery and Anesthesia, University of Toronto, Toronto, Canada.
Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2010 Mar;109(3):372-84. doi: 10.1016/j.tripleo.2009.10.008. Epub 2010 Jan 8.
The aims of this study were to test whether or not the application of an in situ-formed synthetic polyethylene glycol hydrogel (PEG) used as a biodegradable membrane for guided bone regeneration with a variety of graft materials and ambient oxygen or hyperbaric oxygen (HBO) environments would result in enhanced bone regeneration, and to observe the histologic and histomorphometric aspects of bone healing of the calvarial defects with and without a PEG membrane.
Thirty adult, skeletally mature, male New Zealand white rabbits were randomly divided into 3 groups of 10 animals each. Bilateral 15-mm-diameter critical-size defects were created in the parietal bones of each animal. Group 1 served as a control with unfilled bilateral calvarial defects, group 2 had bilateral calvarial defects filled with morcelized autogenous calvarial bone, and group 3 had bilateral calvarial defects filled with a biphasic calcium phosphate ceramic. One of the calvarial defects was randomly protected with a PEG resorbable liquid membrane in each animal. Five animals from each group underwent a course of HBO treatment (2.4 ATA 100% oxygen for 90 minutes 5 days a week for 4 weeks) and the other 5 served as control and did not receive any supplemental oxygen (normobaric). The animals were killed 6 weeks after their surgery, and their parietal bones were harvested. The specimens were analyzed with microscopic computerized tomography (microCT) scans and histomorphometrics.
The unfilled normobaric control bony defects did not heal, proving the critical-size nature of these defects. The presence of autogenous bone or bone ceramic in the defects increased the bone volume fraction and bone mineral density of the defects (P < .001). The presence of a membrane in the ungrafted and autogenous bone grafted defects resulted in a decrease in the corrected bone volume fraction (P = .002) but not in the bone ceramic grafted defects (P = .580). Bony healing of defects where the membrane was unsupported was compromised; the membrane did not maintain the desired bone regeneration volume with the unfilled and autogenous bone grafted groups. The PEG resorbable liquid membrane worked best with the bone ceramic material. HBO did not ameliorate the healing of the autogenous bone graft or ceramic filled defects in the 6-week time period of this study.
Although the PEG resorbable liquid membrane is easy to use and forms an occlusive layer, caution is recommended when using the membrane over an unsupported defect. HBO did not ameliorate bony healing with the membrane at the early 6-week time point. The authors recommend future assessment with HBO at the 12-week time point.
本研究旨在测试应用原位形成的合成聚乙二醇水凝胶（PEG）作为可生物降解膜用于多种移植材料的引导性骨再生，以及在环境氧气或高压氧（HBO）环境下是否会促进骨再生，并观察有无PEG膜时颅骨缺损骨愈合的组织学和组织形态计量学方面。
30只成年、骨骼成熟的雄性新西兰白兔被随机分为3组，每组10只动物。在每只动物的顶骨上制造双侧直径15毫米的临界尺寸缺损。第1组作为对照，双侧颅骨缺损不填充；第2组双侧颅骨缺损填充碎块状自体颅骨骨；第3组双侧颅骨缺损填充双相磷酸钙陶瓷。在每只动物中，随机用PEG可吸收液体膜保护其中一个颅骨缺损。每组5只动物接受一个疗程的HBO治疗（2.4ATA 100%氧气，90分钟，每周5天，共4周），另外5只作为对照，不接受任何补充氧气（常压）。动物在手术后6周处死，采集其顶骨。标本用显微计算机断层扫描（microCT）和组织形态计量学进行分析。
未填充的常压对照骨缺损未愈合，证明了这些缺损的临界尺寸性质。缺损中存在自体骨或骨陶瓷增加了缺损的骨体积分数和骨密度（P <.001）。未移植和自体骨移植缺损中存在膜导致校正骨体积分数降低（P =.002），但在骨陶瓷移植缺损中未降低（P =.580）。膜无支撑的缺损的骨愈合受到损害；在未填充和自体骨移植组中，膜未维持所需的骨再生体积。PEG可吸收液体膜与骨陶瓷材料配合效果最佳。在本研究的6周时间内，HBO并未改善自体骨移植或陶瓷填充缺损的愈合。
虽然PEG可吸收液体膜易于使用并形成封闭层，但在无支撑的缺损上使用该膜时建议谨慎。在6周早期时间点，HBO并未改善膜的骨愈合。作者建议在12周时间点对HBO进行未来评估。
