A study of the quality of impressions for anterior crowns received at a commercial laboratory

Abstract

A report is presented of a study which was carried out to investigate the standard of impressions for anterior crowns received at a commercial dental laboratory in Great Britain. Aspects examined were the type of tray and its suitability to the impression technique used, fixation of the impression to the tray, the method of storage in transit, contamination, defects on the preparations and defects elsewhere affecting the occlusion. The quality of the actual preparation was not examined in this study. Similar details were noted for the opposing impression. Of the 50 cases examined only 12 were recorded as totally satisfactory, with 26 cases being recorded as not being of an acceptable standard for the construction of an adequate restoration. The results are presented with the conclusion that in this survey the general quality of impression was unacceptable.

Quality of written prescriptions and master impressions for fixed and removable prosthodontics: a comparative study

“…Sending contaminated materials via the postal system is unethical (not to mention hazardous and illegal) in both Ireland and the United Kingdom. 25,40 The potential for transmission of infective agents from the dental surgery to the dental laboratory via inadequately disinfected impressions has previously been demonstrated. 41 This is a sobering thought in contemporary dental practice where infection with diseases such as HIV, Hepatitis B, and Hepatitis C, present real threats to all members of the oral healthcare team.…”

“…[25][26][27] These studies were performed prior to the introduction of professional guidelines in this area.…”

Contemporary dental practice in the UK: indirect restorations and fixed prosthodontics

“…3 Previous studies have looked at the design and prescription of bridgework, standards of tooth preparation for indirect restorations and impressions, but to date little is known about the materials and techniques that practitioners are using for the provision of indirect restorations and fixed prosthodontics in the UK, let alone the extent to which newer materials and techniques have been adopted. [4][5][6][7][8] The aim of this study was to investigate, by questionnaire, the use and selection of materials and techniques for indirect restorations and fixed prosthodontics by two selected groups of practitioners in the UK. A further aim was to investigate any differences between the two groups with respect to materials and techniques used.…”

Preparing dental students for careers as independent dental professionals: clinical audit and community-based clinical teaching

“…Despite the importance of recording accurate and detailed impressions, evidence from general practice indicates that the quality of impressions for crowns and bridges is less than ideal. [18][19][20] The aim of this audit was to examine the quality of impressions for crowns and bridges within a dental laboratory. Quality ratings were devised for this audit (1 = clinically acceptable with no discrepancies, 2 = some discrepancies but still clinically acceptable, 3 = unacceptable).…”