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Updated: Aug 5, 2026
11:20
Fabrication and Visualization of Capillary Bridges in Slit Pore Geometry
Published on: January 9, 2014
Variations in bridge construction in commercial laboratories
A Johnson1, R B Winstanley, S E Northeast
1Department of Restorative Dentistry, University of Sheffield School of Clinical Dentistry, Charles Clifford Dental Hospital.
Restorative Dentistry
|August 1, 1991
Summary
Dental laboratories showed significant variation in constructing porcelain bonded to metal bridges. Inconsistent prescriptions likely contributed to these quality differences in fixed bridge restorations.
Area of Science:
- Dental materials science
- Prosthodontics
- Dental laboratory technology
Background:
- Porcelain bonded to metal (PBM) bridges are common fixed dental prostheses.
- Quality control in dental laboratory services is crucial for patient outcomes.
- Variability in PBM bridge fabrication can impact clinical success and patient satisfaction.
Purpose of the Study:
- To assess the quality and consistency of PBM three-unit fixed bridges produced by commercial dental laboratories in the UK.
- To identify potential factors contributing to variations in bridge quality.
Main Methods:
- Identical working models for a PBM three-unit fixed bridge were sent to 30 UK dental laboratories.
- Bridges were fabricated and returned for examination.
- Acceptability was evaluated using subjective clinical and technical criteria.
Main Results:
- A wide variation in the quality and acceptability of the fabricated PBM bridges was observed.
- Significant inconsistencies were noted between bridges produced by different laboratories.
- The quality of the prescription provided to the laboratories was identified as a potential contributing factor.
Conclusions:
- Commercial dental laboratories exhibit considerable variability in PBM bridge fabrication.
- The use of standardized and comprehensive laboratory prescriptions is essential to improve consistency and quality.
- Further investigation into prescription adequacy and laboratory quality assurance is warranted.
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