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Cement Excess at Single Implant Crowns Malmö/Lund

University of Zurich (UZH) logo

University of Zurich (UZH)

Status

Completed

Conditions

Tooth Loss
Gingivitis and Periodontal Diseases

Treatments

Device: implant crown

Study type

Interventional

Funder types

Other
Industry

Identifiers

NCT04015427
2018-414

Details and patient eligibility

About

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.

Enrollment

24 patients

Sex

All

Ages

18+ years old

Volunteers

Accepts Healthy Volunteers

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

Trial design

Primary purpose

Treatment

Allocation

Randomized

Interventional model

Crossover Assignment

Masking

Single Blind

24 participants in 2 patient groups

screw-retained
Active Comparator group
Description:
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.
Treatment:
Device: implant crown
cement-retained
Active Comparator group
Description:
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.
Treatment:
Device: implant crown

Trial documents
1

Trial contacts and locations

1

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Data sourced from clinicaltrials.gov

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