Biomaterial Database

The quality of impressions for crowns and bridges received at commercial dental laboratories. 1997

R B Winstanley, and P V Carrotte, and A Johnson

Department of Restorative Dentistry, School of Clinical Dentistry, University of Sheffield.

OBJECTIVE To determine the quality of impressions for crown and bridge work made in general dental practice. METHODS All impressions for crown and bridge work which had been sent to four commercial dental laboratories in the UK were assessed by two examiners, each laboratory being visited on two occasions. METHODS 290 cases which had been received by the laboratories on the days of the visits were assessed for a number of factors related to quality. There was no selection or rejection--all impressions received were examined. RESULTS Flexible plastic trays were used for the majority of working impressions for crown and bridge work in general dental practice (72%), many had been re-used (> 13%), defects in the recording of the prepared teeth were common, and cross infection control was not routine. CONCLUSIONS Quality standards for impressions for crown and bridge work in general dental practice in the UK are a cause for concern if the sample of cases seen in this study is typical.

UI	MeSH Term	Description	Entries
D007284	Inlays	Restorations of metal, porcelain, or plastic made to fit a cavity preparation, then cemented into the tooth. Onlays are restorations which fit into cavity preparations and overlay the occlusal surface of a tooth or teeth. Onlays are retained by frictional or mechanical factors.	Dental Inlays,Dental Onlays,Onlays,Dental Inlay,Dental Onlay,Inlay, Dental,Inlays, Dental,Onlay, Dental,Onlays, Dental,Inlay,Onlay
D007574	Jaw Relation Record	A registration of any positional relationship of the mandible in reference to the maxillae. These records may be any of the many vertical, horizontal, or orientation relations. (Jablonski, Illustrated Dictionary of Dentistry)	Axiography,Bite Registration,Sirognathography,Record, Jaw Relation,Records, Jaw Relation,Bite Registrations,Jaw Relation Records,Registration, Bite,Registrations, Bite
D007754	Laboratories, Dental	Facilities for the performance of services related to dental treatment but not done directly in the patient's mouth.	Dental Laboratories,Dental Laboratory,Laboratory, Dental
D010969	Plastics	Polymeric materials (usually organic) of large molecular weight which can be shaped by flow. Plastic usually refers to the final product with fillers, plasticizers, pigments, and stabilizers included (versus the resin, the homogeneous polymeric starting material). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Plastic
D011176	Post and Core Technique	Use of a metal casting, usually with a post in the pulp or root canal, designed to support and retain an artificial crown.	Dental Dowels,Dental Dowel,Dowel, Dental,Dowels, Dental,Post Technic,Post Technique,Post and Core Technic,Post-Core Technic,Post Technics,Post Techniques,Post-Core Technics,Technic, Post,Technic, Post-Core,Technics, Post,Technics, Post-Core,Technique, Post,Techniques, Post
D011787	Quality of Health Care	The levels of excellence which characterize the health service or health care provided based on accepted standards of quality.	Pharmacy Audit,Quality of Care,Quality of Healthcare,Audit, Pharmacy,Care Quality,Health Care Quality,Healthcare Quality,Pharmacy Audits
D003442	Crowns	A prosthetic restoration that reproduces the entire surface anatomy of the visible natural crown of a tooth. It may be partial (covering three or more surfaces of a tooth) or complete (covering all surfaces). It is made of gold or other metal, porcelain, or resin.	Dental Crowns,Crown, Dental,Crowns, Dental,Dental Crown,Crown
D003760	Dental Impression Materials	Substances used to create an impression, or negative reproduction, of the teeth and dental arches. These materials include dental plasters and cements, metallic oxide pastes, silicone base materials, or elastomeric materials.	Dental Impression Material,Impression Material, Dental,Impression Materials, Dental,Material, Dental Impression,Materials, Dental Impression
D003761	Dental Impression Technique	Procedure of producing an imprint or negative likeness of the teeth and/or edentulous areas. Impressions are made in plastic material which becomes hardened or set while in contact with the tissue. They are later filled with plaster of Paris or artificial stone to produce a facsimile of the oral structures present. Impressions may be made of a full complement of teeth, of areas where some teeth have been removed, or in a mouth from which all teeth have been extracted. (Illustrated Dictionary of Dentistry, 1982)	Dental Impression Technic,Dental Impression Technics,Dental Impression Techniques,Impression Technic, Dental,Impression Technics, Dental,Impression Technique, Dental,Impression Techniques, Dental,Technic, Dental Impression,Technics, Dental Impression,Technique, Dental Impression,Techniques, Dental Impression
D003779	Denture Design	The plan, delineation, and location of actual structural elements of dentures. The design can relate to retainers, stress-breakers, occlusal rests, flanges, framework, lingual or palatal bars, reciprocal arms, etc.	Denture Designs,Design, Denture,Designs, Denture