Effect of package weight on the total amount of die stone used annually in a dental school

PURPOSE

This study compared the total amount of Type IV dental stone (die stone) used annually by dental students when they were supplied with either 70-g or 140-g preweighed packages of die stone.

MATERIALS AND METHODS

In September 1994, all the bulk containers of die stone were removed from the student dental clinic and laboratories and replaced by 70-g preweighed packages of die stone (Silky-Rock; Whip Mix, Louisville, KY). At the end of August 1998, all 70-g packages of die stone were removed from the student dental clinic and laboratories. The average annual number of 70-g packages of preweighed die stone used by the students from 1994 to 1998 was calculated. From September 1998 to the end of August 1999, only 140-g preweighed packages of die stone (Silky-Rock) were supplied to the students. The number of the 140-g packages of preweighed die stone and total weight used by students during this period were calculated and compared with the average annual number of 70-g preweighed packages of die stone used during the 1994-1998 period.

RESULTS

From September 1994 to August 1998, the students used an annual average of 4060 +/- SD 250 of the 70-g packages (284.2 +/- 17.5 kg per annum). From September 1998 to August 1999, the students used 3360 of the 140-g packages (470.4 kg).

CONCLUSIONS

Although the students used in total 700 fewer of the 140-g die stone packages per annum than the annual average number of 70-g packages, they used 186.2 kg (65.5%) more die stone when supplied with the 140-g packages.

The dental student as a technician: preclinical and clinical laboratory programs in fixed prosthodontics

PURPOSE

A 2-part survey of United States dental schools was conducted. The first part of the survey was published in 1998 and determined the curricular structure, techniques taught, and materials used in predoctoral fixed prosthodontics courses. The purpose of the second part of the survey was to ascertain the delegation of laboratory procedures in preclinical and clinical fixed prosthodontic programs.

MATERIALS AND METHODS

The survey was mailed to the course directors of predoctoral fixed prosthodontic programs at 53 US dental schools. Of these, 42 schools returned the completed survey, resulting in a response rate of 79%.

RESULTS

Results from this survey show that certain laboratory procedures in preclinical and clinical fixed prosthodontics are completed by dental laboratories (either in-house or commercially available laboratories).

CONCLUSIONS

For the preclinical programs of fixed prosthodontics, there is more student involvement in the completion of laboratory procedures in the dental schools surveyed. In clinical fixed prosthodontic programs, there is a high emphasis on patient care and less on laboratory techniques that can be delegated to laboratory technicians.

Planning oral rehabilitation: case-based computer assisted learning in clinical dentistry

The partially edentulous adult offers a unique and problem-rich resource as a basis for a case-based learning scenario in clinical dentistry in the field of planning oral rehabilitation. However, there is little resource material available to help students negotiate the territory between diagnosis and treatment options of discrete conditions and treatment sequencing once decisions have been made. To address the educational void surrounding the teaching and learning of oral rehabilitation strategies, the authors have developed a CD-ROM 'Interactive Learning in Dentistry: Decision making in the oral rehabilitation of the partially edentulous adult'. The disc emphasises the distinction between 'doing' and 'planning to do' in the decision-making process. After using the disc the students should be able to apply a generic framework to formulate a custom oral rehabilitation plan for their own patient. The disc was evaluated by final-year students from the Faculty of Dentistry, University of Sydney. Response to the program was essentially positive and comments from students have impacted on further development.

The use of group participation and an enquiry-based study guide with computer assisted learning

The aim of this investigation was to explore the use of group participation and an enquiry-based study guide to enhance the learning experience when using a computer assisted learning (CAL) program.

MATERIALS AND METHODS

Forty-eight students were asked to complete a CAL program on resin bonded bridges in groups of 2-4 with an enquiry-based study guide. An evaluation questionnaire of the learning experience was included with the study guide with paired positive and negative questions and open-ended questions for students to complete and return. The responses were collated and the nature of the comments qualitatively analysed.

RESULTS

Thirty-two questionnaires were returned. There were almost three times the numbers of positive to negative responses relating to the usefulness of the enquiry based study guide, group participation and the CAL program. The majority of these positive responses related to the usefulness of the study guide and group participation in highlighting and guiding learning and creating opportunities for discussion, problem solving and peer teaching. A small number of negative responses cited the target-orientated nature of the study guide and the longer time needed for group work, due to the varying learning abilities of the participants and the need for discussion.

CONCLUSION

The use of group participation and an enquiry-based study guide was reported to enhance the learning experience of CAL.

The use of specific dental school-taught restorative techniques by practicing clinicians

In 1995, a survey requesting information about the utilization of certain prosthodontic techniques was mailed to 3,544 graduates of a midwestern dental school. Responses were received from 1,455 alumni, representing a 41 percent return rate. In general, the results are consistent with international and national trends and show significant disparity in the utilization rates of certain procedures between general dentists and prosthodontists, as well as a disconnect between what is taught in the undergraduate dental educational program and what is applied in practice. For example, while prosthodontists typically apply what was taught in their educational program, utilization rates of general dentists for the facebow was 29.64 percent; the custom tray 68.48 percent; border molding 58.67 percent; altered casts 24.10 percent; custom posts 49.29 percent; prefabricated posts 67.54 percent; and semi-adjustable articulators 50.64 percent. While no solutions to this disconnect are offered the authors do pose important questions that must be addressed by the dental educational community.

Operator-induced compressive axial forces during implant gold screw fastening

STATEMENT OF PROBLEM

The gold screw of an implant is put under tension during fastening. An increase in operator-induced compressive axial force during fastening may diminish screw tension, lower the friction between the screw threads, and allow for increased tightening torque.

PURPOSE

This study was undertaken to assess and compare the compressive axial forces and torques placed simultaneously on implant gold screws by persons with varying degrees of expertise.

MATERIAL AND METHODS

A calibrated electric torque driver was used to fasten implant gold screws. Three groups of operators with various levels of implant experience (faculty [F; n = 4], prosthodontic residents [R; n = 4], and undergraduate dental students [S; n = 6]) were asked to repeatedly tighten and loosen a new gold abutment screw into a standard 3.75-mm diameter Branemark abutment. Compressive axial forces during torquing were assessed over the tightening time by means of a miniature load cell adapted to the electric torque driver. Each operator repeated the experiment 3 times after calibration. Within operator and between operator reliability were evaluated.

RESULTS

Loosening compressive axial forces were always higher than tightening compressive axial forces, and peak torque was less on loosening than tightening. Faculty placed a smaller range of forces on the screws (mean = 3.29 N, SD +/- 1.45 N) than did the residents (mean = 2.74 N, SD +/- 1.96) or the students (mean = 3.01 N, SD +/- 2.54).

CONCLUSION

The clinical experience of operators seems to influence their application of compressive axial force during gold screw tightening. Less torque during unfastening of gold screws seems to be related to increased axial loading.

The use of real time video magnification for the pre-clinical teaching of crown preparations

OBJECTIVE

To investigate the effect on the undergraduate learning process of using an alternative method designed to enhance the visual demonstration of taper on full veneer crown preparations (better understanding of the value of taper on preparations early in the teaching programme in restorative dentistry).

DESIGN

A comparison between the conventional teaching of full veneer crown preparations and the same teaching with the additional use of a magnified real time video display using a surgical microscope was investigated in this study.

OUTCOME MEASURES

The degree of taper was measured for replica full crown preparations and results compared between different cohorts of undergraduates and experimental conditions.

RESULT

Undergraduates taught using the real time video produced more accurately tapered preparations. This ability was retained over one year.

CONCLUSIONS

A possible explanation for the result was that the use of magnification improved the undergraduates' precise understanding of taper by enhancing their ability to evaluate this critical measurement during the teaching process.

Students' evaluation of online course materials in fixed prosthodontics: a case study

PURPOSE

The purpose of this study was to assess a new online course format for dental students. Preclinical Fixed Prosthodontics I is a didactic and laboratory course given in the first year of the dental school curriculum. In the spring semester of 1999, the didactic portion of the course was offered in a web-based format as a supplement to the traditional lecture format.

METHODS

The study population was 53 first year dental students at one school. The study design was a one group post test without a control group. The online questionnaire consisted of multiple choice questions, Leikert scale questions and open-ended questions. Data were collected using Filemaker Pro and analyzed using Epilnfo.

RESULTS

Student response rate was 96% (52/53). All of the students responded that they felt comfortable with their computer skills in utilizing this course format. Most (96%) responded that the online materials were either very helpful or helpful to them. About half, (54%) recommended that the online format be continued as a supplement to traditional lectures, while 28% recommended replacing traditional lectures with the new format in order to provide more laboratory time in the course. The syllabus, lecture materials, bulletin board and handouts were found to be the most helpful online features. The least helpful features were the listserve, decision tree, and e-mail options. Most frequently mentioned strengths of the online material were listed as 1) the ability to view material at their own pace and at a time convenient to them, 2) quality photographs in lecture materials and 3) online quizzes. Weaknesses of the course were ranked by students as 1) problems with access to the materials and the intranet system, 2) taking quizzes online and 3) difficulty in printing the web-based lecture materials.

CONCLUSIONS

The delivery of web-based material as a course supplement in Fixed Prosthodontics I was determined to be an overall success. Fine tuning of problems with access to the materials took place throughout the course. The student feedback will help direct future development of web-based course materials in the dental school curriculum.

Teaching an abbreviated impression technique for complete dentures in an undergraduate dental curriculum

STATEMENT OF PROBLEM

Traditional methods for teaching complete denture fabrication are time-consuming, difficult to master, and not used by many general practitioners.

PURPOSE

This study compared the efficacy of traditional denture fabrication techniques with a more abbreviated method in a dental school setting.

MATERIAL AND METHODS

A retrospective record review of 80 completely edentulous patients treated by predoctoral dental students was completed. Forty patients were treated with traditional denture techniques; the other 40 patients were treated with an abbreviated method. The data abstracted included the number of visits to completion and the number of postinsertion visits and relines required within the first 3 months after delivery. A Wilcoxon rank sum test was performed to determine statistical significance between the groups with regard to number of visits for fabrication and postinsertion adjustments. A test for a difference in proportions by using the normal approximation to the binomial distribution was performed for statistical analysis of the incidence of relines.

RESULTS

The abbreviated denture technique resulted in a statistically significant difference in the number of visits for fabrication (P<.01) and postinsertion adjustments (P<.05.) There was no difference (P=.39) in the number of relines between the 2 groups.

CONCLUSION

Teaching the abbreviated complete denture technique in an undergraduate dental clinic decreased the number of appointments necessary to complete denture therapy without increasing the number of adjustments or reline procedures.

A comparison between videotaped and live demonstrations, for the teaching of removable partial denture procedures

AIM

This study was devised to test the effectiveness of videotaped demonstrations as opposed to live demonstrations, to small groups of undergraduate dental students. The outcome was assessed by comparing the students' understanding of the clinical and laboratory technical stages of the altered cast impression technique, which is used in the construction of removable partial dentures.

METHOD

31 students watched a series of videotaped demonstrations and 30 received a similar series of live demonstrations. The altered cast procedure was divided into 5 distinct stages, each of which was assessed with the aid of agreed criteria, initially by the students and then by 2 staff assessors and these results were compared. The students were subsequently asked to rate how helpful the videotaped or live demonstration had been on a 5-point scale.

RESULTS

The live demonstration group showed better agreement between the students' assessment and the assessors' assessment of the quality of the work for the first part of the clinical stage. There was no difference in the groups' assessment of the final outcome of this clinical stage and the subsequent laboratory technical stages. Students who observed the live demonstrations indicated higher scores for its helpfulness in performance of all the stages of the technique, when compared to those who had observed a videotaped demonstration.

CONCLUSION

Both teaching methods developed a similar level of understanding of the principles behind the exercise, although the students preferred the live demonstrations. A carefully produced videotaped demonstration can be a useful alternative to a live demonstration in teaching the short and clear cut technique selected for this study.

Continuing dental education in osseointegrated implants. A survey

A survey of participants in a continuing education course in osseointegrated implants was carried out to determine dentists' attitudes toward such courses and how they were integrating implants into their everyday practice. The results indicated, despite the intense program, very few general dentists who attended such a course chose to actively participate in implant placement and a moderate number chose to carry out prosthetic restoration. Those who attended such courses appeared satisfied with the course content, appreciated the difficulties involved with implant placement and restoration and generally chose to refer such cases to appropriate specialists for management. This pilot study confirms dental implants are a popular and accepted mode of therapy. However, general dental practitioners who take the time to undergo specific training in osseointegrated implants appear to be less inclined to actively participate in the placement (surgery) of implants. Following appropriate training, many general practitioners felt comfortable in performing the restorative/prosthetic aspect of implant treatment for single tooth rather than partial or full denture cases. In conclusion, while continuing education courses in osseointegrated implants are becoming increasingly popular, this survey indicates participants become aware of the complexity of the procedures involved and tend to actively participate mainly in the prosthetic reconstruction of simple cases.

Socio-economic characteristics and personal attitudes of patients attending a French prosthodontic teaching clinic

The aims of the study were to define the socio-economic characteristics of patients attending a Teaching Hospital Prosthetics Department and to determine the attitudes and aspirations of such patients. The study was performed on 162 patients who requested prosthetic treatment in a French university dental hospital department. They were asked to complete a questionnaire at the beginning of their treatment. The questionnaire was composed of 2 parts, covering respectively: firstly, social, economic, and demographic data concerning the patients, the source of referral and the primary motivation for their decision to request treatment, and secondly comments concerning their prosthetic treatment. The results show the socio-professional and socio-economic diversity of this population. In most cases, the patients were recommended to the university hospital service by their relatives or friends. Among the criteria proposed, they indicate that cost and quality of treatment were their major motivation. Analysis of the patients' comments identifies some factors responsible for the lack of efficiency associated with care and dental education.

Medico-legal aspect of dental implants

The practising environment in health care is ever changing in both clinical and management areas. Within dentistry, two major changes have occurred with the development of implantology into a sound treatment approach and a burgeoning of dental litigation. There are medico-legal issues that relate to dental implant treatment with which clinicians must become familiar and there are medico-legal implications that impact on risk management by Medical Indemnity Organizations (MDOs) and the indemnity premiums they set for their members. The aim of this paper is to discuss these issues and highlight those areas of significance to clinicians.

The size of occlusal rest seats prepared for removable partial dentures

OBJECTIVE

The aim of this study was to test whether rest seats cut by a group of general dental practitioners for a removable partial denture differed in size and shape from those prepared by either a group of postgraduate students or their academic teachers.

METHOD

The occlusal surfaces of a number of plastic teeth were scanned by a laser profilometer. Each tooth was then placed in a set of articulated phantom head dental arches. 30 dental practitioners, 16 postgraduates and 11 dental academics were asked to cut a rest seat preparation in the mesial marginal ridge suitable for the construction of a removable chromium cobalt partial denture. The tooth was removed from the models, rescanned, and this data converted to grey level images for measurement of the width, length and area of each rest seat. Depth was calculated as the difference between the pre and post preparation scanned profiles.

RESULTS

There was a wide variation in the size of the individual rest seat preparations. There was no significant difference between the measured parameters from the images of the preparations made by academic staff and postgraduate students. The two sets of data were therefore combined. The length, width and area of the rest seats prepared by the staff and postgraduate group were significantly greater than those cut by the dental practitioner group. However, there was no significant difference in the depths measured. The outline form of the rests prepared by the dental practitioners was often round with sharply defined margins contrasting with the smooth triangular preparation the staff and postgraduates prepared.

CONCLUSION

A 'refresher' in tooth modification for GDPs designing partial dentures would improve the long term success of the prosthesis.

Assessment of objectives of post-doctoral general dentistry programs in Canada

Objectives of hospital-based post-doctoral general dentistry programs in Canada were assessed by questionnaire. Seventy percent (14 of 20) of the program directors responded. Educational goals and objectives were assessed in professional skills and practice management, public health and preventive dentistry, oral medicine and pathology, special needs patient care, trauma and emergency care, restorative/prosthodontic care, endodontics, orthodontics/pediatric dentistry, oral surgery, periodontics, pharmacology, and functioning in a hospital. High rankings of proficiency were related to primary care, restorative/prosthodontic, endodontic, and surgical care. Emergency care, sedation, and pharmacology were also ranked highly. Lower rankings of proficiency were reported in orthodontics, aspects of public health dentistry, practice management, and advanced oral and maxiliofacial surgery. When the results of the Canadian survey were compared with those of a survey of US post-doctoral general dentistry programs, substantial similarity was seen. The findings support continuing reciprocity in accreditation standards between the Canadian and American Commissions on Dental Education and Dental Accreditation.

Quality of fixed restorative treatment on Brånemark implants. A 3-year follow-up study in private dental practices

The aim of the present prospective study were to describe the quality of implant supported reconstructions made by dentists previously inexperienced with implant prosthodontics and to evaluate alterations and complications from the moment of insertion to 3 years later. Before starting with the prosthodontic work, the dentists had participated in a 2-day postgraduate course focusing on planning and practical training. Forty-nine patients were clinically examined within 4 months after insertion of the fixed implant supported prosthesis. Three years later 39 of the 49 participants underwent a second examination by the same independent examiner. Thirty-one patients had a complete rehabilitation (25 with resin teeth bonded to a metal framework and 6 ceramo-metal bridges); 8 patients had partial ceramo-metal reconstructions. The parameters assessing the quality of the restoration were design, fit, occlusion/articulation and esthetics. Oral hygiene and health of the peri-implant tissues were also examined. Each parameter was scored as perfect, acceptable, to be corrected or to be redone. These scores were a modification of "The guidelines for the assessment of clinical quality and professional performance of the Californian Dental Association". The initial prosthodontic quality was rated perfect to acceptable except for one restoration which had an unacceptable fit and had to be modified. After 3 years of function the quality did not change except for esthetics which worsened for resin bonded teeth (P < 0.05). The esthetic appearance of ceramo-metal reconstructions were unaltered. The peri-implant condition was predominantly healthy and stable during 3 years. The conclusion of the present study is that dentists previously inexperienced with implant prosthodontics implemented the information from a training course satisfactorily. They were able to make a clinically acceptable restoration with a quality that was stable after 3 years except for discoloration in resin bonded teeth. This, however, had no effect on patient's opinion and satisfaction.

Analyses of treatment outcomes for complete dentures provided in an undergraduate teaching programme

Identifying the source of difficulties some patients experience after replacement dentures are made is an essential part of improving quality care should further treatment to assist the patient be considered necessary. This report examines the findings of a retrospective review of 181 patients' records following the provision of complete dentures by undergraduate dental students at the University of Otago School of Dentistry. Treatment was provided in 1998; the audit commenced in August 1999 to allow sufficient time for the records to include review appointments. Forty-eight patients (26.5 percent) were recommended to receive further replacement dentures to correct errors identified by the supervising clinician. Causation was broadly attributed to dissimilarities from patients' previous dentures (42 percent), occlusal factors (33 percent), and difficulties in establishing a functional denture-bearing area (11 percent). These findings were compared with a published analysis of denture faults identified during the clinical examination of patients referred to a specialist in dental prosthetics. Evidence suggests that the use of a clinical technique which incorporates information from previously successful dentures may be appropriate in the construction of replacement dentures.

Centric relation definitions taught in 7 dental schools: results of faculty and student surveys

PURPOSE

The purpose of this investigation was to assess the level of consensus regarding the definition of centric relation and its clinical use in 7 US dental schools.

MATERIALS AND METHODS

The preclinical and clinical faculty in the departments of prosthodontics, operative, and general dentistry (n = 137) at 7 dental schools and a convenience sample of fourth year students (n = 150) at the same schools were invited to complete 2-page surveys regarding the definitions and use of centric relation at their institutions. The faculty and student survey included 6 commonly used centric relation definitions from the 1994 Glossary of Prosthodontic Terms, and provided space for writing in definitions not listed on the form. The participants were asked to identify which definition was used at their school.

RESULTS

Return rate was 85% for faculty and 75% for students. Both faculty and students identified a low level of consensus regarding the definition and clinical use of centric relation at their dental school. Numerous definitions are in use at each institution. Extramural practice participation and the number of years since dental school graduation were variables associated with the faculty's choice of definition. The faculty who did not participate in an extramural practice chose older definitions. Dental educators graduating before 1975 selected either the oldest or the most recent centric relation definition, whereas the more recent graduates frequently selected the newer definitions. There were no statistical differences between prosthodontic specialists and nonspecialists in choice of definitions. Three courses identified by the students as having the most influence on their understanding of centric relation were preclinical removable prosthodontics, preclinical occlusion, and clinical removable prosthodontics.

CONCLUSION

The results of this survey suggest that the controversy will continue, because to date there is no consensus regarding the definition of centric relation within the 7 dental schools surveyed.

Irrigation rates and handpieces used in prosthodontic and operative dentistry: results of a survey of North American dental school teaching

PURPOSE

A data baseline on dental cutting methodologies was established by means of a survey of North American dental school teaching.

MATERIALS AND METHODS

Sixty-four North American dental schools were surveyed regarding their recommendations on handpiece usage and coolant flow rates in fixed prosthodontics and operative dentistry.

RESULTS

High-speed handpieces were the instruments of choice for tooth preparation in fixed prosthodontics. In operative procedures, recommendations for sole use of the high-speed, the low-speed, or both handpiece types were more uniform.

CONCLUSIONS

North American dental schools advocate greater use of high-speed than low-speed handpieces. Although the use of high-speed handpieces predominate in schools in Canada and Puerto Rico, there is a proportionately higher use of low-speed handpieces than in US dental schools. Few (approximately 1 in 5) schools made recommendations on coolant flow rates during cutting procedures.