Biomedical subjects

N H F Wilson

Publications and source records attributed to N H F Wilson.

23 records · Page 2Linked to original sources

PubMed2002

Influence of the method of funding on the age of failed restorations in general dental practice in the UK.

OBJECTIVE: This study examined the effect of the method of funding treatment on the age of restorations at the time of replacement. METHOD: A group of general dental practitioners were recruited to take part in the study. Each participant was asked to record the reason for placement and replacement of restorations. The age and class of the restoration being replaced was also recorded, together with details of the material being used and the material being replaced. Details of the method of payment of the failed restoration were recorded. RESULTS: Details of the reason for placement/replacement were received for 3,196 restorations from 32 GDPs. Of the restorations placed, 54% were amalgam, 32% composite, 8% compomer and 7% glass ionomer. The age of restorations at the time of replacement was significantly associated with the method of payment for the restoration, with restorations placed in the Armed Forces having been in service significantly longer at the time of their replacement than restorations placed under NHS regulations. CONCLUSION: Statistical analysis indicated that restorations placed within the NHS regulations were replaced at a significantly lower age than restorations placed under the other funding arrangements investigated.

Age Factors↗

PubMed2002

Current trends in restorative dentistry in the UK: a Delphi approach.

OBJECTIVES: The purpose of the study was to obtain insight into current trends in restorative dentistry in the UK by means of a Delphi technique. METHODS: A panel of nine experts was convened to define areas where changes were thought to occur in contemporary restorative dentistry. The defining statements obtained were circulated amongst the Panel to reach consensus on the content and wording, and then formatted into a questionnaire which was distributed amongst 407 clinical academic staff in Restorative Dentistry in UK dental schools. Good agreement with a statement was defined as a score of > or =70%, statements that received such scores were taken as indicating possible trends. RESULTS: The Expert Panel reached consensus on the wording of 21 defining statements, which were formatted into a 23-item questionnaire. The questionnaire achieved a useable response rate of 70%, and the academic respondents reached good agreement on 15 (65%) of the statements. CONCLUSIONS: The 15 statements which received scores of 70% or greater were considered to be possible indicators of trends in aspects of the clinical practice of restorative dentistry in the UK.

Consensus↗

PubMedDate not supplied

A practice-based, randomized, controlled clinical trial of a new resin composite restorative: one-year results.

This study evaluated the performance of a low-shrinking resin composite compared with an amalgam for restoration of Class I and II cavities of moderate size in posterior teeth in a general practice setting. Fifty-two pairs of test and control restorations were placed in 49 patients. Clinical evaluations and assessments of replica models were carried out at baseline, six months and one year. Patients recorded their level of satisfaction with the restorations by means of visual analog scales. Apart from one control restoration that failed due to a fractured cusp, all of the restorations reviewed at six months and one year were intact with no unacceptable scores for any of the evaluation criteria. It was concluded that the resin composite evaluated, when used in conjunction with the recommended adhesive system, may be an appropriate alternative to amalgam in the restoration of posterior teeth over one year in clinical service.

Adolescent↗

PubMedDate not supplied

Failure risk of posterior composites with post-operative sensitivity.

Post-operative sensitivity (POS) may be observed in recently placed posterior composites. Evidence-based guidelines for the management of posterior composites with POS have yet to be determined. This study examined a retrospective analysis of the findings of a unique multi-center clinical trial to investigate the five-year risk of failure of posterior composites with POS and to determine the factors likely to have an important impact on the prognosis of the restorations. Longitudinal five-year data from the multi-center trial of Occlusin were analyzed. Data pertaining to a total of 1,101 restorations were included in the study. The failure rate at five years was calculated by means of three selected methods for all the restorations included in the study and for restorations with POS. Risk of failure for restorations with POS was analyzed by calculating an odds ratio along with the 95% confidence interval (CI). Logistic regression was carried out in order to identify those factors most likely to have had an important impact on the prognosis of restorations with POS. The analysis revealed that the restorations of Occlusin with POS were found to have been more likely to have failed at five years than the restorations of Occlusin without POS, with odds ratios ranging from 1.73 (95% CI: 1.04, 2.87) to 1.97 (95% CI: 1.36, 2.85). Distributions of patient age and cavity size were significantly different for successful and failed restorations (chi-square test, p < 0.05). Logistic regression indicated that cavity size was the only factor likely to have influenced the prognosis of the restorations with POS (p = 0.041, odds ratio 3.21, 95% CI 1.05: 9.70). Restorations with POS in large cavities were more likely to have failed by five years than restorations in small cavities. It was concluded that the restorations with Occlusin included in the Occlusin trial program were more likely to have failed at five years if POS occurred within one month of placement. Cavity size has been shown to have been an important factor in the prognosis of Occlusin trial restorations with POS.

Adult↗

PubMedDate not supplied

The performance of air-turbine handpieces in general dental practice.

OBJECTIVE: To investigate variation in performance measures of fibre-optic, high-speed air-turbine handpieces during the course of daily use in general dental practice. MATERIALS AND METHODS: Four groups of five new high-speed fibre-optic handpieces were used in the routine treatment of patients over a period of 30 months by four general dental practitioners in two dental practices: Groups A, B: Super-Torque Lux 3 650B (KaVo, Biberach, Germany); Group C: BORA 898LE (BienAir SA, Bienne, Switzerland) and Group D: Toplight (W&H Dentalwerk, Burmoos, Austria). The dental practice teams had been rehearsed in the procedures to be followed before starting the study. Each dentist used the handpieces in strict rotation, while the groups were rotated monthly between practitioners. Four performance characteristics were measured before use, then at regular intervals: free-running speed (Hz) and bearing resistance (microNm) were measured using a purpose-built testing machine (Darvell-Dyson); illuminance (lux) and sound pressure level (dB(A)) were also measured. Handpieces were cleaned and lubricated in accordance with manufacturers' directions; all were autoclaved wet at 134 degrees C for three minutes. RESULTS: Free-running speed showed an initial increase after use for Groups A, B and C, which may be associated with a decrease in bearing resistance. All handpieces in Group C suffered bearing failure between months 21 and 23, preceded by a substantial increase in noise, while those in Group D suffered failure of the fibreoptic system between months 18 and 24. Other deterioration due to use was identified but Groups A, B and D were still in use at month 30. CONCLUSIONS: Variation in free-running speed, bearing resistance, illuminance and sound pressure level can be used effectively to monitor changes in air-turbine handpieces due to normal use. Although an increase in bearing resistance is associated with decreasing free-running speed, noise appears to be a useful indicator of imminent bearing failure. Assiduous adherence to manufacturers' directions for cleaning and lubrication may have contributed to increased bearing life.

Air↗