软组织垂直厚度对牙周炎患者种植修复临床效果的影响

目的 观察牙周炎病史患者种植后的中,长期临床效果,探讨软组织垂直厚度对植体周组织健康及植体周病发生的影响.方法: 根据种植术中测量的植入位点软组织垂直厚度,将66名患者的66颗植体分为正常组(normal,软组织垂直厚度 ≤4.5 mm)及过厚组(thick,软组织垂直厚度 >4.5 mm)两组.随访至少2年后进行复查,记录植体留存情况,植体周探诊深度,出血指数,菌斑指数,植体周边缘骨吸收量及植体周病发生情况,并进行统计分析,比较两组之间的差异.结果: 植体留存率为100%.复查时过厚组植体的植体周探诊深度最大值(max PDi),植体周探诊深度平均值(mean PDi),植体周出血指数最大值(max BIi),植体周出血指数平均值(mean BIi),植体近中边缘骨吸收量平均值,植体远中边缘骨吸收量平均值,植体周边缘骨吸收量平均值,植体周菌斑指数平均值(mean PLIi)均显著高于正常组(P＜0.05).此外,正常组复查时植体周炎发病率2.3%,过厚组复查时植体周炎发病率34.8%,两组植体周炎发病率的差异有统计学意义(P＜0.05).结论: 牙周炎患者种植位点的软组织垂直厚度对植体周软硬组织健康存在显著影响;过厚的软组织垂直厚度与植体周探诊深度及植体周边缘骨吸收量增多有关,最终可能增加植体周病的发病风险.

Effect of vertical soft tissue thickness on clinical manifestation of peri-implant tissue in patients with periodontitis

Objective: To observe and investigate the effect of vertical soft tissue thickness on the peri-implant tissue condition and the prevalence of peri-implant disease in patients with history of periodontitis. Methods: Among 210 patients who showed initial interest of implant therapy, 92 patients were included in this study and received implant surgery during 2010 and 2015. Sixty-six patients with 66 implants finally came back for T2 evaluation. Prior to the implant therapy, all the patients had received periodontal treatment. During the implant placement surgery, the distance from palatal soft tissue edge to the alveolar crest, which was defined as vertical soft tissue thickness (VT), was measured after the buccal full thickness flap was elevated. According to the cut off point which was adopted from the operating characteristic curve, 66 implants within 66 patients were divided into two groups, which were called normal group (VT≤4.5 mm) and thick group (VT>4.5 mm), respectively. Information of the patient's general status, periodontal situation and implant information were recorded. After a follow-up period of 42.9 months, the parameters of peri-implant tissue and condition of peri-implant disease were recorded. Mann-Whitney U test as well as Chi-square test were used to compare the parameters between two groups. Moreover, Kaplan-Meier method was chosen to draw the event(peri-implantitis)-free survival curve. Results: The survival rate of the implants was 100%. At the end of the follow-up examination(T2), the parameters including max PDi, mean PDi, max BIi, mean BIi, mean MBL, MBL at distal side, MBL at mesial side, mean PLIi presented significantly higher values in thick group than in normal group (P ＜ 0.05). Moreover, the prevalence of peri-implantitis and peri-implant disease(peri-implant mucositis & peri-implantitis) in thick group was respectively 34.8% and 73.9%, which was significantly higher than 2.3% and 48.8% respectively in normal group (P＜0.05). The prevalence of peri-implant mucositis did not show significant difference in the two groups. In addition, Kaplan-Meier analysis showed that there was significant difference between the event-free survivals of the two groups. Conclusion: The vertical soft tissue thickness around implants in patients with periodontitis has a significant effect on the health of the peri-implant tissue. Excessive vertical soft tissue thickness may result in deeper peri-implant probing depth as well as more peri-implant marginal bone loss, and eventually increase the risk of peri-implant disease. The vertical remodeling of soft tissue may be a new direction to indicate the role of periodontitis in peri-implant tissue condition. Moreover, the biological mechanism of the association between soft tissue thickness and peri-implantitis risk as well as effective approaches to prevent the adverse effect of excessive soft tissue thickness on peri-implant tissue is necessary to be investigated.