Clinical, Microbiological and Histological Effects of Cemented Implant Restorations. A Cross-over Controlled Clinical Study
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 24
- 试验地点
- 1
- 主要终点
- Analysis of microbiological parameters
研究概览
简要总结
Abstract
Aim:
The primary aim of this study is to test whether or not cement residues in the submucosal environment of implants lead to a change in the microbiota and induce inflammation of the periimplant tissues.
Material and Methods:
24 patients in need of a single tooth replacement will be enrolled in this cross-over controlled clinical study. All patients will receive a two-piece dental implant, which will be restored with both a cemented and a screw-retained single crown. At the time of impression taking, patients will be randomized into two groups.
Patients in group A will receive a screw-retained crown. Every 8 weeks microbiological samples using sterile paper points will be collected and analyzed for bacterial content by real-time PCR. Additionally, two host markers (MMP8, IL-1ß) will be determined by ELISA. Following this first period of 16 weeks, the screw-retained crown will be replaced by a new intraorally cemented crown. Cement removal will be preformed according to best clinical procedure. These crowns will again be left for another period of 16 weeks and followed up for the harvesting of microbiological samples every 8 weeks. After the second 16-week the crowns will be removed to evaluate any excess cement. All patients will be fitted with the original screw-retained crown. Clinical parameters for inflammation and probing depths will be obtained after each 16 week-period.
In group B the crowns will be incorporated in a reverse pattern. During the first 16 weeks any possible cement residues will be removed according to best clinical procedure, while for the second period of 16 weeks patients will be fitted with a screw-retained single crown. Again, microbiological and clinical parameters will be obtained at the same intervals as in Group A.
After the second 16 week period the screw-retained crowns will be (re-) inserted in all patients, single tooth x-rays taken and clinical baseline values obtained. Additionally, a soft tissue biopsy will be harvested at the time of insertion of the final screw-retained crown. Patients will be followed up for another 16-week period.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Treatment
- 盲法
- Single (Outcomes Assessor)
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •- patient older than 18 years
- •systemically healthy subject
- •periodontally healthy individuals
- •absence of peri-implantitis
- •no bone loss
- •good oral hygiene (PCR ≤ 20%)
- •healthy periodontal tissues (BoP≤ 20%)
- •patients with a single tooth gap in the posterior area of either jaw (premolars and molars)
- •at least 8mm in mandible; at least 6mm in maxilla (summers technique)
排除标准
- •- ongoing periodontal disease
- •unwilling to comply with study procedures
- •heavy smokers (≥10 cig/d)
- •ongoing periodontitis/implantitis
研究组 & 干预措施
screw-retained
Patients in group A will receive a screw-retained implant crown. Following this first period of 16 weeks, the screw-retained implant crown will be replaced by a new intraorally cemented implant crown. Cement removal will be preformed according to best clinical procedure. These implant crowns will again be left for another period of 16 weeks and followed up for the harvesting of microbiological samples every 8 weeks. After the second 16-week the implant crowns will be removed to evaluate any excess cement. All patients will be fitted with the original screw-retained implant crown. Clinical parameters for inflammation and probing depths will be obtained after each 16 week-period.
干预措施: implant crown (Device)
cement-retained
In group B the implant crowns will be incorporated in a reverse pattern. During the first 16 weeks a cemented implant crown will be inserted and any possible cement residues will be removed according to best clinical procedure, while for the second period of 16 weeks patients will be fitted with a screw-retained single implant crown. Again, microbiological and clinical parameters will be obtained at the same intervals as in Group A.
干预措施: implant crown (Device)
结局指标
主要结局
Analysis of microbiological parameters
时间窗: Change BL to 16 weeks post-restoration
Change relative percentage of gram-negative microorganisms
次要结局
- Histomorphometric analysis(32 weeks after BL)
- Immunohistologic analysis - putative periodontal pathogens(32 weeks after BL)
- Immunohistologic analysis - MMP8(32 weeks after BL)
- Immunohistologic analysis - IL1ß(32 weeks after BL)
- Analysis of inflammation markers on RNA-basis - (IL-4, IL-3, IL-1alfa, IL-1beta)(32 weeks after BL)
- Analysis of inflammation markers on RNA-basis - TNF-alfa(32 weeks after BL)
- Clinical parameters - Probing Depth(Every 8 weeks until 48 weeks and again at the 1-year follow-up)
- Clinical parameters - Bleeding-on-Probing(Every 8 weeks until 48 weeks and again at the 1-year follow-up)
- Clinical parameters - Plaque Index(Every 8 weeks until 48 weeks and again at the 1-year follow-up)