Gingivitis and Periodontal Diseases, Tooth Loss
Conditions
Keywords
cement, dental, implant, implant prosthodontics
Brief summary
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.
Interventions
DEVICEimplant crown
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.
Sponsors
Folktandvården Skåne AB
Göteborg University
Dentsply Sirona Implants and Consumables
University of Zurich
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* \- 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)
Exclusion criteria
* \- ongoing periodontal disease * bruxism * unwilling to comply with study procedures * heavy smokers (≥10 cig/d) * ongoing periodontitis/implantitis
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Analysis of microbiological parameters | Change BL to 16 weeks post-restoration | Change relative percentage of gram-negative microorganisms |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Immunohistologic analysis - IL1ß | 32 weeks after BL | The biopsies will be used for the determination of inflammation and infection markers applying light-microscopy. Gingival crevicular fluid (GCF) will be collected using standardized filter paper strips. |
| Clinical parameters - Probing Depth | Every 8 weeks until 48 weeks and again at the 1-year follow-up | In order to assess the inflammatory status of the peri-implant tissue, different parameters will be assessed: 1) plaque index (dichotomous values) 2) keratinized tissue width (continuous) 3) BOP (dichotomous), 4) PD (continuous), 5) recession (continuous) |
| Clinical parameters - Bleeding-on-Probing | Every 8 weeks until 48 weeks and again at the 1-year follow-up | In order to assess the inflammatory status of the peri-implant tissue, different parameters will be assessed: 1) plaque index (dichotomous values) 2) keratinized tissue width (continuous) 3) BOP (dichotomous), 4) PD (continuous), 5) recession (continuous) |
| Clinical parameters - Plaque Index | Every 8 weeks until 48 weeks and again at the 1-year follow-up | In order to assess the inflammatory status of the peri-implant tissue, different parameters will be assessed: 1) plaque index (dichotomous values) 2) keratinized tissue width (continuous) 3) BOP (dichotomous), 4) PD (continuous), 5) recession (continuous) |
| Histomorphometric analysis | 32 weeks after BL | A soft tissue biopsy will be harvested at the time of insertion of the final screw-retained implant crown in all patients. The biopsies will be used for histomorphometric measurements. |
| Immunohistologic analysis - putative periodontal pathogens | 32 weeks after BL | The biopsies will be used for the determination of inflammation and infection markers applying light-microscopy. Gingival crevicular fluid (GCF) will be collected using standardized filter paper strips. A battery of 10 putative periodontal pathogens will be analyzed using real-time PCR. |
| Immunohistologic analysis - MMP8 | 32 weeks after BL | The biopsies will be used for the determination of inflammation and infection markers applying light-microscopy. Gingival crevicular fluid (GCF) will be collected using standardized filter paper strips. |
| Analysis of inflammation markers on RNA-basis - (IL-4, IL-3, IL-1alfa, IL-1beta) | 32 weeks after BL | Tissue samples will further be processed with a (ribonucleic acid) RNA solution to allow for RNA extraction. This will then be analyzed via polymerase chain reaction (PCR) to determine expression patterns of markers such as Interleukin (IL-4, IL-3, IL-1alfa, IL-1beta) and tumor necrose factor (TNF-alfa). |
| Analysis of inflammation markers on RNA-basis - TNF-alfa | 32 weeks after BL | Tissue samples will further be processed with a (ribonucleic acid) RNA solution to allow for RNA extraction. This will then be analyzed via polymerase chain reaction (PCR) to determine expression patterns of markers such as Interleukin (IL-4, IL-3, IL-1alfa, IL-1beta) and tumor necrose factor (TNF-alfa). |
Other
| Measure | Time frame | Description |
|---|---|---|
| Radiological outcomes | 12 weeks pre-BL, BL and 1year post-BL | A single-tooth x-ray will be obtained at the time of implant placement and again at abutment connection in order to ensure sufficient osseointegration of the implant before entering the prosthetic phase. At the time of insertion of the respective reconstruction in both groups, another periapical radiograph will be obtained to ensure the fit of the reconstruction and to check for eventual cement residue. A final x-ray will be taken at insertion of the final screw-retained implant crown to serve as baseline regarding marginal bone level at the time of final crown insertion. |
| Determination of additional inflammatory markers - IL-1ß | 4 times 8 weeks | The collected microbiological samples will additionally be analyzed for two host markers (MMP8, IL-1ß) that will be determined by ELISA. |
| Determination of additional inflammatory markers - MMP8 | 4 times 8 weeks | The collected microbiological samples will additionally be analyzed for two host markers (MMP8, IL-1ß) that will be determined by ELISA. |
Countries
Sweden
Outcome results
None listed