AimTo determine the effects of implant timing and type of soft‐tissue grafting on histological and histomorphometric outcomes in a preclinical model.Materials and MethodsFour implant placement protocols were randomly applied at the mesial root sites of the third and fourth mandibular premolars in 10 mongrel dogs: immediate placement (group IP), early placement (group EP), delayed placement with/without alveolar ridge preservation (groups ARP and DP, respectively). A connective‐tissue graft (CTG) or porcine‐derived volume‐stable collagen matrix (VCMX) was applied to enhance the ridge profile (simultaneously with implant placement in group IP and staged for others), resulting in five sites for each combination. All dogs were sacrificed 3 months after soft‐tissue grafting. Histological and histomorphometric analyses were performed, and the data were analysed descriptively.ResultsCTG and VCMX were difficult to differentiate from the augmented area. The median total tissue thickness on the buccal aspect of the implant was largest in group IP/CTG (between 2.78 and 3.87 mm). The soft‐tissue thickness was generally favourable with CTG at all implant placement timings. Within the DP groups, CTG yielded statistically significantly larger total and soft‐tissue thickness than VCMX (p < .05). Among the groups with VCMX, group EP/VCMX showed the largest soft‐tissue thickness at apical levels to the implant shoulder.ConclusionsCTG generally led to greater tissue thickness than VCMX.

中文翻译：

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种植体植入时间和软组织移植类型对临床前犬模型中组织学和组织形态学结果的影响


目的在临床前模型中确定植入时间和软组织移植类型对组织学和组织形态学结果的影响。材料和方法在 10 只犬的第三和第四下颌前磨牙的近中根部部位随机应用四种种植体植入方案：立即放置（IP 组）、早期放置（EP 组）、延迟放置有/没有牙槽嵴保留（分别为 ARP 和 DP 组）。应用结缔组织移植物 （CTG） 或猪来源的体积稳定胶原蛋白基质 （VCMX） 以增强脊剖面（与第 IP 组中的植入物植入同时进行，并为其他人分期），导致每个组合有五个部位。所有狗在软组织移植后 3 个月处死。进行组织学和组织形态学分析，并对数据进行描述性分析。结果CTG 和 VCMX 难以与增强区域区分开来。IP/CTG 组种植体颊侧的中位总组织厚度最大 （在 2.78 至 3.87 mm 之间）。在所有种植体植入时间，CTG 的软组织厚度通常都是有利的。在 DP 组中，CTG 的总组织和软组织厚度在统计学上显著大于 VCMX （p < .05）。在 VCMX 组中，EP/VCMX 组在种植体肩部顶端水平的软组织厚度最大。结论CTG 通常比 VCMX 导致更大的组织厚度。