Clinical trial NCT04015427: Cement Excess at Single Implant Crowns Malmö/Lund
Official title: Clinical, Microbiological and Histological Effects of Cemented Implant Restorations. A Cross-over Controlled Clinical Study
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Gingivitis and Periodontal Diseases
Tooth Loss
Keywords: cement
dental
implant
implant prosthodontics
Lead sponsor: University of Zurich
Sponsor class: OTHER
Collaborators: name: Folktandvården Skåne AB
name: Göteborg University
name: Dentsply Sirona Implants and Consumables
First posted: 2019-07-11
Enrollment: 24
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: TREATMENT

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.


Eligibility criteria: 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

Primary outcomes:
measure: Analysis of microbiological parameters
timeFrame: Change BL to 16 weeks post-restoration
Secondary outcomes:
measure: Histomorphometric analysis
timeFrame: 32 weeks after BL
measure: Immunohistologic analysis - putative periodontal pathogens
timeFrame: 32 weeks after BL
measure: Immunohistologic analysis - MMP8
timeFrame: 32 weeks after BL
measure: Immunohistologic analysis - IL1ß
timeFrame: 32 weeks after BL
measure: Analysis of inflammation markers on RNA-basis - (IL-4, IL-3, IL-1alfa, IL-1beta)
timeFrame: 32 weeks after BL
measure: Analysis of inflammation markers on RNA-basis - TNF-alfa
timeFrame: 32 weeks after BL
measure: Clinical parameters - Probing Depth
timeFrame: Every 8 weeks until 48 weeks and again at the 1-year follow-up
measure: Clinical parameters - Bleeding-on-Probing
timeFrame: Every 8 weeks until 48 weeks and again at the 1-year follow-up
measure: Clinical parameters - Plaque Index
timeFrame: Every 8 weeks until 48 weeks and again at the 1-year follow-up
Other outcomes:
measure: Determination of additional inflammatory markers - MMP8
timeFrame: 4 times 8 weeks
measure: Determination of additional inflammatory markers - IL-1ß
timeFrame: 4 times 8 weeks
measure: Radiological outcomes
timeFrame: 12 weeks pre-BL, BL and 1year post-BL
Locations:
city: Lund
country: Sweden
facility: Folktandvården Skåne
state: Skåne
Study officials:
References: