不同软组织替代物在比格犬尖牙唇侧区域移植后附着龈的厚度和组织学变化

The histological and thickness changes of attached gingiva following grafting with different soft tissue substitutes in the labial region of the cuspids in Beagles

背景:上皮下结缔组织移植被认为是软组织增量术的金标准,然而,自体移植需要开辟第二术区,延长手术时间,增加患者的疼痛感,这也使得软组织替代物成为研究热点。目的:比较不同软组织替代物在比格犬尖牙唇侧区域移植后移植区附着龈厚度和组织学变化。方法:在3只比格犬尖牙唇侧附着龈区域,分别用双层同种异体脱细胞真皮基质膜(allograft acellular dermal matrix,AADM)、牛源性脱细胞真皮基质(bovine acellular dermal matrix,BADM)联合浓缩生长因子膜以及BADM联合胶原蛋白海绵进行附着龈增厚。分别在术前和术后1,2,3,4个月测量附着龈厚度,术后4个月进行组织学观察。结果与结论:①术后第1-4个月,双层AADM组附着龈厚度及附着龈厚度增量均值高于其他2组(均P<0.05);②术后1个月3组附着龈厚度显著增加,而后呈下降趋势;术后3个月,BADM联合胶原蛋白海绵组与BADM联合浓缩生长因子组移植区附着龈厚度变化较术前差异无显著性意义(P>0.05);术后4个月,双层AADM组附着龈厚度均值较术前仍显著增加(P<0.05);第1-4个月双层AADM组附着龈厚度值最高,其次为BADM联合胶原蛋白海绵组,BADM联合浓缩生长因子组最低;③双层AADM组真皮基质与宿主牙龈组织良好的结合在一起,并可见新生纤维结缔组织和成纤维细胞长入基质内,另外两组移植物已经完全吸收,增量区域改建成与周围宿主组织一致的结构;④结果说明,AADM在牙龈增厚方面优于BADM联合浓缩生长因子膜和BADM联合胶原蛋白海绵。

BACKGROUND:Subepithelial connective tissue grafts are generally considered as the gold standard for soft tissue augmentation.However,it needs a second surgical site,which will prolong the surgical time and increase patients’pain.OBJECTIVE:To compare the histological and thickness changes of attached gingiva following grafting with different soft tissue substitutes in the labial region of the cuspids.METHODS:In three Beagle dogs,attached gingival augmentation was performed with double-layer allogeneic acellular dermal matrix membrane(AADM),bovine-derived acellular dermal matrices(BADM)combined with concentrated growth factor membrane or BADM combined with collagen sponge.Thickness of attached gingiva was measured before augmentation,and 1,2,3,and 4 months after augmentation.Histological analyses were performed after 4 months.RESULTS AND CONCLUSION:The mean values of attached gingival thickness and attached gingival thickness augmentation were higher in the double-layer AADM group than in the other two groups(all P<0.05)from the 1^(st)to 4^(th)month after surgery.At 1 month after surgery,the attached gingival thickness of the three groups increased significantly and then decreased.At 3 months after surgery,the BADM combined with collagen sponge group and the BADM combined with concentrated growth factor membrane group showed no significant difference in the attached gingival thickness of the graft area compared with that before surgery(P>0.05).At 4 months after surgery,the mean value of attached gingival thickness in the double-layer AADM group was still significantly increased compared with that before surgery(P<0.05).The value of attached gingival thickness was highest in the double-layer AADM group,followed by the BADM combined with collagen sponge group,and the lowest in the BADM combined with concentrated growth factor membrane group at 1-4 months after surgery.Histological analyses revealed that AADM was well integrated with the host gingival tissue,and new fibrous connective tissue and fibroblasts grew into the AADM.But the grafts in the other two groups were absorbed and the augmentation area was remodeled into a structure consistent with the surrounding host tissue.To conclude,AADM is superior to BADM combined with concentrated growth factor and BADM combined with collagen sponge with regard to gingival augmentation.