An RCT of 2 bridge designs in terms of aesthetics and failure rate.
Research type
Research Study
Full title
A randomised clinical trial to determine the aesthetics outcomes and failure rates of a new compared to the current design of resin-retained bridge.
IRAS ID
257107
Contact name
Nicola West
Contact email
Sponsor organisation
Univeristy of Bristol, Research Goverance, Human Tissue Manager, Reseach and Enterprise Development
Duration of Study in the UK
1 years, 11 months, 28 days
Research summary
Patients attending Bristol Dental Hospital for tooth replacement for reasons such as hypodontia (missing teeth) or trauma are currently treated using a Bristol bridge. The Bristol bridge is a type of metal framed resin retained bridge (RRB) in which the pontic (the ‘false tooth’) is bonded to an adjacent tooth/teeth via a metal frame and composite resin. The metal frame (retainer) acts as a connector between the adjacent tooth and the false tooth and extends behind the false tooth and wraps around the incisal edge (tip of the tooth). While the majority of the metal is invisible as it is hidden behind the false tooth and supporting tooth, when the patient smiles, if the bridge is on the anterior (front) teeth the portion of metal at the incisal edge may be visible or cause changes to the translucency of the incisal edge resulting in a small grey flash appearance. At review appointments some patients say that this change in their appearance is upsetting, and in a previous study the metal of the retainer was reported to be the most common reason for patient dissatisfaction with their RRB. The Bristol bridge can be adjusted to reduce the visibility of the metal edge of the bridge, but it will always be apparent. When the Bristol bridge was designed it was deemed necessary for the metal to extend right to the tip of the bridge to improve its longevity, however with improved bonding materials and better fit of bridges due to the use Computer Aided Design and Computer Aided Manufacturing (CAD/CAM) it should now be possible to redesign the bridge with a reduced extension such that aesthetics are not compromised. This study aims to determine if changes to the current RRB design can improve aesthetic outcomes without adversely affecting failure rates.
REC name
London - Brighton & Sussex Research Ethics Committee
REC reference
19/LO/0618
Date of REC Opinion
28 May 2019
REC opinion
Further Information Favourable Opinion