Changing patterns and the need for quality.

J G Steele; R W Wassell; A W G Walls

doi:10.1038/sj.bdj.4801317

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Changing patterns and the need for quality.

J G Steele·R W Wassell·A W G Walls

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Abstract

This series of articles is aimed at anybody who places crowns and other extra-coronal restorations (ie veneers and shims) on individual teeth. We hope that everyone from experienced practitioners to undergraduate students may find something of value. Whoever reads them, we would ask to do so with an open mind. We have tried not to be dogmatic, and the techniques and materials described are not the only ones available, but are the ones which accord with the principles we describe.

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Crowns Dental Restoration Failure Humans Practice Patterns, Dentists'Retreatment State Dentistry United Kingdom Journal Article

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J G Steele, R W Wassell, A W G Walls. 2002-02-09. Changing patterns and the need for quality.. https://doi.org/10.1038/sj.bdj.4801317

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PubMed2006

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PubMed2006

Assessment of the amount of remaining coronal dentine in root-treated teeth.

OBJECTIVES: There is currently no standardised technique to measure the amount of coronal dentine remaining in a root-treated tooth after crown preparation. The aim of this study was to develop a method of measuring remaining coronal dentine in root-treated teeth and to propose an index for grading tooth restorability. METHODS: The study recruited 20 patients who had completed molar endodontic treatment at the Eastman Dental Hospital and had been prescribed an amalgam coronal-radicular core with a full coverage cast restoration. Using a series of interlocking special trays and impressions, a method was devised to produce a cast of the amount of remaining dentine coronal to the finish line after crown preparation. This cast was scanned using a laser profilometer and the volume of remaining dentine was calculated. A tooth restorability index (TRI) was developed to assess the strategic value of the remaining dentine. The TRI allowed scores of 0-3 in each sextant with a maximum score of 18 per tooth. RESULTS: Twenty teeth were scored by three examiners and the TRI scores varied from 2 to 13. The volume of coronal dentine varied from 61.73 to 232.22 mm(3). CONCLUSIONS: A tooth restorability index has been devised to assess the strategic value of remaining dentine. A Kappa statistic was calculated to produce values of 0.584, 0.688 and 0.720, giving moderate-good agreement between the examiners.

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