G. M. G. Hommez, M. Braem & R. J. G. De Moor
Department of Operative Dentistry and Endodontology, Ghent University, Ghent University Hospital, Dental School, Gent, Belgium.
Department of Dental Materials, University of Antwerp, Campus RUCA, Antwerpen, Belgium.

Introduction.
When postgraduate teachers discuss with practitioners the subjects they would like to see covered in courses, endodontics is often mentioned. Attendees on such courses generally wish to learn how to make endodontic treatment quicker, easier and more successful (Carrotte 2000a).
It is known that the standard of root canal treatment carried out by general dental practitioners in Europe is poor (Saunders et al. 1997,Weiger et al. 1997, Marques et al. 1998, De Moor et al. 2000, Kirkevang et al. 2001, Hommez et al. 2002). It has been reported that one of the causes of such poor quality treatment in general practice may be that students graduate with a lack of expertise and a poor understanding of the principles involved (Dummer 1991). The recent European Society of Endodontology Undergraduate Curriculum Guidelines for Endodontology (ESE 2001) advocate that endodontics should be taught in clinical areas dedicated to that purpose, and that an appropriate number of cases should be treated. On the other hand, it could be argued that following some time in practice, the clinical expertise of dentists should have improved. In the present Belgian accreditation system, where courses in different subjects of dentistry have to be followed, the number of endodontic courses (most of them combining theory and preclinical exercise) should be sufficient to improve the performance of dentists. However, there is little evidence to demonstrate whether the information provided by these courses is used in clinical practice.
The purpose of this study was to gather information on the nature of root canal treatment carried out by a group of dentists attending peer review sessions as a part of the programme of the Belgian accreditation system. Specific information regarding root canal cleaning and shaping was obtained with a standard questionnaire handed to dentists attending peer review sessions organized by the ‘Interuniversitaire Samenwerking’ (Inter University Cooperation of the Flemish Universities). The aim of the questionnaire was not only to collect baseline data, but also to determine the endodontic knowledge of dentists. Furthermore, it was hoped to gain an insight into potential problems regarding endodontic treatment procedures that could explain the present standard of root canal treatment carried out by general dental practitioners.

Materials and methods.
A total number of 312 dentists who attended peer review sessions in the year 2000, organized by the ‘Interuniversitaire samenwerking’ i.e. the Universiteit Gent/Ghent University (RUG), the Katholieke Universiteit Leuven/ Catholic University of Leuven (KULeuven), the Vrije Universiteit Brussel/Free University of Brussels (VUB), the Universiteit Antwerpen/University of Antwerp (UA, RUCA), the Limburgs Universitair Centrum (LUC) and the Katholieke Universiteit Leuven Campus Kortrijk (KULAK), were asked to complete a questionnaire at the beginning of a peer review session. The questionnaires were anonymous. Of all Flemish dentists, 60% participated in peer review sessions that were part of the o⁄cial accrediting system (Government figures supplied by the ‘Rijksdienst voor Ziekte- en Invaliditeitsverzekering’).
Part one of the questionnaires covered personal information: university of graduation, years of practical experience, gender, part-time or full-time occupation, and if applicable, whether a particular clinical speciality was practised.
Part two of the questionnaire covered general information regarding root canal treatment: the use of rubber dam; the number of root canal treatments per week; the number of visits for one, two, three and four canals; the frequency of treatment of the fourth canal in maxillary first and second molars and the frequency of C shaped canals in mandibular molars.
In part three the practitioners were asked about their methods for cleaning and shaping canals and the products and materials used. The following topics were covered: canal irrigants and chelators, working length determination, instruments and technique used for canal preparation.
When a list of possible answers was given, the practitioners were invited to choose the answer that best fitted their clinical practice. In most of these cases the range of answers was well defined so that there was no need to make additional responses. Space was provided when additional comments were necessary in the event of the usual practice not being adequately covered by the choice given.
One operator processed all questionnaires using excel 2000 (Microsoft Corporation, Redmond, WA, USA). For detailed comparisons, the sample was divided into groups according to years of practical experience or the years since graduation as follows: group 1, up to 5 years; group 2, 6-10 years; group 3,11-15 years; group 4,16-20 years; group 5, 21-25 years and group 6, more than 25 years.