体外预备根片改良盾构术的动物实验研究

Animal Experimental Study on Modified Socket-shield Technique with in Vitro Root Preparation

目的:通过分析改良盾构术的影像学及组织学表现,探索改良盾构术的可行性与有效性,探索降低传统盾构术技术敏感性的方法。方法:本实验使用6条健康比格犬,双侧下颌第3、第4前磨牙沿颊舌向行半切后截除近中或远中牙冠。在实验位点偏舌侧预备种植窝,然后拔除残根,在体外预备根片后再植于拔牙窝原位,即刻植入种植体。潜入式愈合3个月后行CBCT检查及组织学检查,观察种植体骨结合及根片的牙周愈合情况。结果:3个月后,临床观察未出现种植体周围炎及种植失败等并发症,CBCT显示所有种植体均形成良好的骨结合,组织学显示根片颊侧出现替代性吸收或者表面吸收,根片与种植体之间有新骨形成,颊侧牙槽嵴均保存良好。结论:在严格控制根片离体时间及储存介质的情况下,在体外预备并再植根片的改良盾构术具有可行性,可降低传统术式的技术敏感性,但改良盾构术尚处于初步研究阶段,需要进行更长期的动物实验研究及临床试验。

Objective:To investigate the feasibility and effectiveness of modified socket-shield technique so as to explore the method to reduce the sensitivity of traditional socket-shield technique by analyzing the cone-bean computed tomography(CBCT)and histological findings.Methods:Six healthy beagle dogs were used in this study.The third premolar(P3)and the fourth premolar(P4)on both sides of the mandible were hemisected in the buccal-lingual direction,and the clinical crown of the distal or mesial root was cut off.The implant bed on the lingual side of the root was prepared.The root fragment was extracted,prepared in vitro,and then replanted in situ.Immediate implantation was performed.After 3 months of submerged healing,the specimens were performed with CBCT observation and histological examination.Results:After 3 months,no complications such as peri-implant inflammation and implant failure were observed.CBCT showed that all implants formed osseointegration.Histology showed that the root fragment had replacement or surface absorption.There was new bone formation between the root fragment and the implant,and the buccal alveolar ridge was well preserved.Conclusion:Under strict control of the time and storage medium of replanted root fragment,the modified socket-shield technique with in vitro preparation is feasible and can reduce the technical sensitivity.However,long-term animal experimental studies and clinical trials are needed.