PROJECTS

EFFECT OF A DENTAL DESENSITIZING AGENT
The first research topic with which BRIDGE was involved was an investigation into the efficacy of a desensitizing agent. 5 dentists from BRIDGE joined a further 5 from Prof Burke's PREP PANEL in a clinical trial of Systemp desensitizer (Ivoclar-Vivadent). Ten patients from each dentist with dentine sensitivity had the area of complaint treated with Systemp, with or without prior etching, and were asked to record their perception of the level of pain before treatment and at four intervals thereafter.
Status
Study completed, and published in Primary Dental Care 2004 Jul;11(3):71-6.
"The Effectiveness of Systemp.desensitizer in the treatment of dentine hypersensitivity."
Stewardson DA, Crisp RJ, McHugh S, Lendenmann U, Burke FJ.

ABSTRACT
PURPOSE: This study reports the effectiveness of Systemp.desensitizer (Ivoclar Vivadent, Schaan, Liechtenstein), when used both with and without an acid-etch step, in the treatment of patients with dentine hypersensitivity in UK dental practices. MATERIALS AND METHODS: Ten general dental practitioners (GDPs) were selected from two practice-based research groups. The GDPs were each requested to use Systemp.desensitizer in the treatment of at least ten patients who presented with pain due to dentine hypersensitivity. Systemp.desensitizer was applied to the sensitive dentine area in strict accordance with the manufacturer's handling instructions, except that the patients were divided into two groups. For the first, group NE, the procedure was to isolate the tooth, gently blot it dry with cotton wool pellets, rub Systemp.desensitizer into the tooth for 20 seconds, then gently air-dry it. For the second, group E, the procedure was identical except that after isolation, the treatment area was etched for 15 seconds with 35% phosphoric acid. Patients were asked to complete a pro forma using a 10 cm visual analogue scale designed to provide details of the extent of their pain before treatment, 24 hours post-treatment, one week post-treatment, one month post-treatment, and three months post-treatment. The zero end of the scale was marked 'no pain' and the 10 cm end was marked 'extreme pain'. The percentage change in the patients' perception of their pain, relative to pretreatment, was calculated using repeated measures analysis and suitable follow-up confidence intervals for the mean changes in perceived pain. Comparisons were then made between the treatment groups NE and E. RESULTS: Ninety-one patients completed the first pro forma and 77 completed all the pro formas. Overall, there was a significant reduction in pain at each of the time points after treatment but the pattern of pain reduction across the two groups was different. In general, the non-etched group (group NE) saw an 'immediate' reduction in pain which was then fairly consistent across the longer term, whilst, in general, the etched group (group E) saw less reduction in pain 24 hours after treatment, and then further reduction in pain at both one week and one month after treatment. Thus the non-etched group experienced an early reduction whilst the etched group took longer to perceive a reduction in pain; however, there were no statistically significant differences between the reductions in pain scores between the two groups at any of the time points after treatment. CONCLUSION: It is concluded that Systemp.desensitizer was effective in reducing pain from dentine hypersensitivity in the patients treated, and this finding was unaffected by whether or not the tooth was acid-etched prior to application of the reagent.


CLASS V RESTORATION SURVEY
When the group first started, people were asked what areas of research would interest them. Maryland bridge survival was high on the list along with the desire from several members to look at the problem of restoring class V cavities. To this end, it was decided that a rolling prospective study on the survival of such restorations placed by the group would yield valuable information; especially as the treatment would be being performed by multiple operators in a “real-life” practice environment, and could generate large numbers for analysis. Much discussion took place and a record card was developed to allow the collection of information about each restoration, and associated features. 10 dentists agreed to participate, and to record data on the next 100 class V restorations that they placed. We plan to monitor the success or failure of these 1,000 restorations after 3,5 and hopefully 10 years by auditing the record cards which the dentists hold.
An application was made for funding from the Shirley Glasstone Hughes Memorial Prize Fund to the BDA. We were very pleased to be awarded £31,000 to carry out this study. This has allowed us to reward the 10 dentists with £10 per restoration/data card, and to pay for the other considerable costs involved in running this ambitious project.
Status
A number of these restorations have failed within two years of being placed. Features of these have been compared with those that are still functioning to identify possible explanations for early failure. Results of an initial evaluation were presented at the Pan-European meeting of the International Association of Dental Research held in Dublin in September 2006. A more detailed analysis is underway and a paper will follow.

IADR abstract:
Early Failure of Class V Restorations in General Dental Practice

DA. Stewardson, PH. Thornley, JG. Gilmour, M. Gibbons, ES. McHugh, FJT. Burke.

A wide range of materials is available to restore Class V lesions, but there is little clinical evidence on survival from dental practice to guide clinicians in appropriate selection.
Objective: To identify the factors associated with early failure of Class V restorations in general dental practice.
Method: 7 UK dentists, members of a West-Midlands practice based research group (BRIDGE), each recorded information on 100 consecutively placed Class V restorations. This included patients' details; materials used; tooth and cavity features; occlusion, and placement techniques. The survival of these restorations was assessed at routine recall visits. Data from restorations lost within two years was compared with those surviving beyond two years for any statistically significant differences using Chi2 and appropriate follow-up tests (p=0.05).
Results: Data on 642 restorations were available. 89 (13.9%) restorations had failed within two years. A significantly greater proportion of restorations placed under NHS funding failed within two years compared with those funded privately (p<0.001). The percentage of early failures among practitioners ranged from 0% - 30.3%, but this can be partially explained by the relative numbers of private and NHS patients seen by each dentist. There were fewer early failures for cavities not entirely within dentine (p<0.001); where there was prior caries (p=0.001); no moisture contamination (p=0.013), and when prepared with a bur (p<0.001). Compomer restorations had a higher proportion of early failure than other materials (p=0.025).
Conclusions: Some clinical and operative factors influence the early survival of Class V restorations. Further analysis is necessary to establish whether these factors are also the root cause of the increased proportion of early failures associated with the method of treatment funding and with individual clinicians.



EFFECT OF RECTANGULAR COLLIMATION ON RADIOGRAPH QUALITY

Peter Thornley developed this study from a clinical audit project, which allowed him to recoup the cost of some of his lost time. We also received help from Kodak who gave all the double film packs used and some additional money which was used to purchase the rectangular collimators for the dentists. Peter had the impression from introducing the rectangular collimators which are now to be used in practice, that the number of retakes had increased. This may be offsetting the reduction of radiation dose associated with rectangular collimators. He recruited 8 dentists who took consecutive bitewing radiographs on 25 patients using their round collimator, and then a further 25 bitewings on different patients using a rectangular collimator. He enlisted the help of Mr. John Rout, consultant radiologist at Birmingham Dental School who assessed the radiographs for positioning and general quality.
Status
Now published in Primary Dental Care 2004 Jul;11(3):81-6.
Rectangular collimation and radiographic efficacy in eight general dental practices in the West Midlands.
Thornley PH, Stewardson DA, Rout PG, Burke FJ.

ABSTRACT
INTRODUCTION: Rectangular collimation is recommended in order to reduce radiation doses to patients. However, anecdotal reports suggest that it may result in more retakes, with a possible net increase in patient dosage. METHOD: To test this hypothesis, eight general dental practitioners were recruited to participate in a project. Each took 25 pairs of bitewing radiographs of patients before and 25 after fitting rectangular collimators to their x-ray machines. Double-pack films were used so that duplicates could be examined. These were assessed by a consultant oral radiologist according to the National Radiographic Protection Board (NRPB) grading system for positioning and general film quality. RESULTS: Initially, positioning quality was above the target level for six of the eight dentists; however, for all but one, this dropped after using rectangular collimation. General film quality was of a lower overall standard initially. Using rectangular collimation had an effect on general film quality but the direction and size of this varied among the dentists. CONCLUSION: It was concluded that amongst the participating dentists, although numbers of retakes increased by 7%, there would be a net reduction in dosage to patients following rectangular collimation.


The results of this survey prompted Peter to go on to look at processing of radiographs in general practice. The Velopex company had produced the Vischeck device, and Peter wanted to see how well dentists were controlling their processing, and whether this device would be a practical aid to better radiographic quality.

Status
Results Presented at the British Society of Dental Research Birmingham 2004
Now published in the British Dental Journal 2006 May 13;200(9):515-9.

Assessing the quality of radiographic processing in general dental practice.
Thornley PH, Stewardson DA, Rout PG, Burke FJ.

ABSTRACT
OBJECTIVES: To determine if a commercial device (Vischeck) for monitoring film processing quality was a practical option in general dental practice, and to assess processing quality among a group of GDPs in the West Midlands with this device. DESIGN: Clinical evaluation. SETTING: General dental practice, UK, 2004. METHOD: Ten GDP volunteers from a practice based research group processed Vischeck strips (a) when chemicals were changed, (b) one week later, and (c) immediately before the next change of chemicals. These were compared with strips processed under ideal conditions. Additionally, a series of duplicate radiographs were produced and processed together with Vischeck strips in progressively more dilute developer solutions to compare the change in radiograph quality assessed clinically with that derived from the Vischeck. RESULTS: The Vischeck strips suggested that at the time chosen for change of processing chemicals, eight dentists had been processing films well beyond the point indicated for replacement. Solutions were changed after a wide range of time periods and number of films processed. The calibration of the Vischeck strip correlated closely to a clinical assessment of acceptable film quality. CONCLUSIONS: Vischeck strips are a useful aid to monitoring processing quality in automatic developers in general dental practice. Most of this group of GDPs were using chemicals beyond the point at which diagnostic yield would be affected.


JOB-SATISFACTION AMONG GENERAL PRACTITIONERS
John Gilmour was concerned with his own and his colleagues job satisfaction, and wanted to find out more about the levels of satisfaction and what influences it. He designed the original questionnaire, and carried out the mailing and data entry. Funding was obtained from the West Midlands Division of the Faculty of general dental practitioners.

This project aims to assess the level of job satisfaction among general dental practitioners in Staffordshire and to assess the association of various personal and work related factors to job satisfaction. Following discussion of the project with the group, John Gilmour's original questionnaire was combined with one which had been successfully assessed and tested in the USA. (We contacted the US professor who had designed this and obtained his permission to use it). This was sent out to all 490 practitioners on the Dental List for Staffordshire.
Status
Results Presented at the British Society of Dental Research Birmingham 2004
Published in the British Dental Journal2005 Jun 11;198(11):701-4.

An assessment of career satisfaction among a group of general dental practitioners in Staffordshire.
Gilmour J, Stewardson DA, Shugars DA, Burke FJ.

ABSTRACT
OBJECTIVES: To assess the level of job satisfaction among general dental practitioners from one area of England, and to assess the association of various personal and work related factors with job satisfaction. DESIGN: Postal questionnaire survey. SETTING: General dental practices in South Staffordshire, Wolverhampton and Dudley, England. METHOD: An anonymous questionnaire posted to all 396 registered dentists in the above areas. RESULTS: A 75% response rate was achieved. Data were analysed using non-parametric statistics for any significant differences in the scores for stress, respect, overall professional satisfaction, quality of life and overall job satisfaction according to the different demographic groupings of the dentists (alpha =0.05). Dentists with an area of special interest had higher scores in all categories except quality of life. Overall job satisfaction was higher among private dentists, and those in group practices and in non-rural locations. The highest bi-variate correlation occurred between overall job satisfaction and overall professional satisfaction, delivery of care, income, respect and professional time. CONCLUSIONS: Job satisfaction was judged to be good among this group. Stress was the factor associated with the greatest dissatisfaction. This survey produced similar results to preceding US studies, and suggests ways of improving job satisfaction.



CROSS-INFECTION POTENTIAL OF CURING LIGHTS
This investigation involved BRIDGE members in a study with researchers from the Birmingham Dental School. Each received £100 for their participation.
Halogen light activation units are used frequently in dental practices on successive patients, but there is scant evidence regarding any disinfection procedures carried out between patients. Curing lights may pose a potential risk of cross-infection from patient to clinical staff and/or other patients. Light emitting diode (LED) light curing units may simplify cross-infection control because of their streamlined design and the absence of a cooling fan exhaust. Dentists from BRIDGE who place more than 5 composite restorations per day were recruited. These practitioners were asked to provide details of their disinfection protocol (written or otherwise) for the light curing unit after patient treatment. . Swabs were taken from three specified sites on their halogen light curing unit before and after treatment of five patients. Each then used an Elipar Freelight for one week, after which swabs were again taken for culture and analysis.
Status

SURVEY OF ATTENDERS IN GDP
This was another co-operative venture, this time with Margaret Gray, Consultant in Dental Public Health in Walsall, West Midlands.