How visible light curing came into dentistry.

The present paper details the history of the introduction of visible light curing into dentistry. This history provides an excellent example of 'out of the box', lateral thinking translation of innovative scientific technology into dentistry. Visible light curing is an important UK contribution to the recent history and current practice of dentistry, with several million visible light curing procedures being carried out globally on a daily basis.

Teaching of the repair of defective composite restorations in Scandinavian dental schools.

Given increased tooth retention into later years of life, dentists face increasing challenges in maintaining teeth with extensive composite restorations. Accompanying the increase in placement of composite restorations in general practice, there has also been increased evidence that repair, rather than replacement, of composite restorations is being increasingly considered as a treatment option. Previous work has demonstrated that such techniques are often underutilised in practice. The aim of this study was to examine contemporary teaching of composite repair techniques in Scandinavian dental schools. A questionnaire was distributed by email to each of the 12 Scandinavian dental schools in late 2010/early 2011. This questionnaire sought information on the undergraduate teaching of composite repair techniques as well as indications and materials utilised for this technique. A 100% response rate was achieved (12 schools). Eleven of the 12 respondent schools indicated that they included the teaching of composite repair techniques within their dental school programme. The most commonly reported indications for the teaching of the repair of direct composite restorations were tooth substance preservation (11 schools) and reduced risk of harmful effects on the pulp (10 schools). The most commonly taught surface treatment was mechanical roughening of the existing composite restoration, including the removal of the surface layer of material, prior to application of fresh composite (11 schools). Overall, the results of this study showed that the teaching of composite repair techniques is established within Scandinavian dental schools. This may influence the practising habits of dentists graduating from these schools when considering treatment options for defective composite restorations.

Teaching of direct composite restoration repair in undergraduate dental schools in the United Kingdom and Ireland.

AIM: To investigate aspects of the teaching of restoration repair as a minimally invasive alternative to the replacement of defective direct composite restorations in teaching programmes in undergraduate curricula in dental schools in the United Kingdom and Ireland. METHODS: An online questionnaire which sought information in relation to the current teaching of composite restoration repair was developed and distributed to the 17 established UK and Irish dental schools with undergraduate teaching programmes in Spring 2010. RESULTS: Completed responses were received from all 17 schools (response rate= 100%). Fifteen schools reported that they included teaching of repair techniques for defective direct composite restorations in their programme. Of the two remaining schools, one indicated that it would introduce teaching of repair techniques during the next five years. The most common indication for a composite repair was that of 'tooth substance preservation' (15 schools). The defects in restorations considered appropriate for repair rather than replacement by the largest number of schools included partial loss of restoration (13 schools) and marginal defects (12 schools). The most commonly taught surface treatment when performing a repair was mechanical roughening of the existing composite with removal of the surface layer (14 schools). Thirteen schools taught etching and the application of an adhesive bonding agent to the prepared surfaces, while the most commonly taught material for completing the repair was a hybrid composite resin (12 schools). Popular finishing implements included diamond finishing instruments (13 schools) and finishing discs (11 schools). CONCLUSION: Not withstanding reluctance amongst general dental practitioners, the teaching of repair of a defective composite restoration, rather than total restoration replacement, is firmly established within UK and Irish dental school programmes. Repair techniques have clear advantages for patients, not least including a minimally invasive approach to treatment and avoidance of unnecessary loss of tooth tissue and pulpal damage. Dental practitioners should look more to repair techniques when managing defective composite restorations and clinical dental teachers should continue to research and refine composite repair techniques.

Defective dental restorations: to repair or not to repair? Part 2: all-ceramics and porcelain fused to metal systems.

With the increasing use of ceramics in restorative dentistry, and trends to extend restoration longevity through the use of minimal interventive techniques, dental practitioners should be familiar with the factors that may influence the decision either to repair or replace fractured metal-ceramic and all-ceramic restorations and, also, the materials and techniques available to repair these restorations. This second of two papers addresses the possible modes of failure of ceramic restorations and outlines indications and techniques in this developing aspect of restoration repair in clinical practice.

Teaching of posterior composites in dental schools in Japan.

The teaching of posterior composites has undergone considerable refinement and development in western countries in recent years. However, little information exists on this teaching in other parts of the world. The aim of this paper is to investigate the teaching of posterior composites to undergraduate dental students in Japan. In late 2007/early 2008, a questionnaire seeking information on the teaching of posterior composites was distributed by email to the person responsible for teaching operative dentistry in each of the 29 dental schools having undergraduate dental degree programmes in Japan. Twenty-three completed responses were returned (response rate = 79%). While all 23 schools taught the placement of composite in occlusal cavities in premolars and molars, 7 schools did not teach the placement of two-surface occlusoproximal composites in premolars (n = 1) and molars (n = 6) and 14 schools and 15 schools do not teach placement of three surface occlusoproximal composites in premolars and molars, respectively. While composite at the time of the survey accounted for 45% of posterior direct restorations placed by students, it is anticipated that this proportion will increase to 59% in 5 years time. Variations were noted between schools in the teaching of principles of cavity design, techniques for restoring proximal contours and light-curing technologies; however, more consistency was observed in techniques used for protecting operatively exposed dentine than that observed in western countries. Despite variations between dental schools being noted in the teaching of certain techniques for posterior composites, the overall extent and content of teaching of posterior composites in Japan could be described as comparable, if not exceeding, than that observed in western countries.

Contemporary dental practice in the UK. Part 1: demography and practising arrangements in 2015.

Objectives: To determine, by means of an anonymous, self-reported questionnaire, the demographic profile and practising details of general dental practitioners in the UK in 2015. Methods: A previously-piloted and validated 121-question questionnaire was distributed during 2015 to 500 dentists at UK dental meetings with a request that they complete the questionnaire and return it by post in the reply-paid envelope to the corresponding author. Results: Three hundred and eighty-eight useable questionnaires were returned, giving aresponse rate of 77.6%. Of the respondents, 60.2% were male and 39.8% female. Theirmean age since graduation was 19.7 years. Just over half of the respondents (50.9%) replied that they were practice principals, 35.8% were associates and 10.6% were foundation dentists. A quarter of the respondents were in single-handed practices, the remainder being in a partnership or group practice. There was a mean of 4.2 dentists per practice, while the mean number of dental therapists in each practice was 0.3 and 1.2 hygienists. Regarding the first available NHS appointment in the respondents' practices for non-urgent care, 23.4% could provide this on the same day, the equivalent figure for private care being 40.1%. The mean percentage of patients receiving NHS treatment was 50%, with 33.8% receiving private treatment. Just over half of respondents considered that Care Quality Commission inspections were 'valuable for fostering patient trust and confidence in dental care.' The collected data indicated that 55.4% of respondents had an intra-oral camera, while, with regard to recently-introduced concepts and techniques, 80.4% used nickel-titanium files, 47.4% used zirconia-based bridgework and 24.9% used tricalcium silicate. Of great interest, perhaps, is the response to digital radiography/digital imaging, with the results indicating that 74.1% of respondents used this form of radiography. Regarding checking the light output of the light curing units, 53.1% stated that they did check the output, but in some cases this might be at a six-monthly interval. Conclusion: Results from this survey indicated that NHS service provision has dropped toapproximately 50% amongst the respondents. Regarding the staffing of dentalpractices, just over half the respondents were practice principals and there was a mean of 4.2 dentists per practice. The results also indicated that UK dentists continue to be innovative in the techniques that they employ.

Dental practice in the UK in 2015/2016. Part 3: aspects of indirect restorations and fixed prosthodontics.

Objective: This paper reports data which helps identify changes and trends in the provision of indirect fixed prostheses in general dental practice in the UK. To determine by means of an anonymous, self-report questionnaire, the current trend in the provision of fixed prosthodontic treatments, with a special emphasis on the choice of treatment modalities, techniques and materials. Methods: The data presented were extracted from the data obtained from a validated,121-question questionnaire distributed at random to general dental practitioners in the UK attending postgraduate meetings in 2015/2016, with a wide distribution of locations. Results: A response rate exceeding 66% was achieved. Amalgam and light-cured composite were the preferred material for core build-up of vital teeth for around 62% of the respondents. Dentine pins were still being used by 66% of the respondents. The vast majority of respondents (92%) used a post and core to restore root-treated teeth. Fibre posts were the most commonly used (63%) type of preformed post among the respondents. Using the opposing and adjacent teeth as a reference to control tooth structure reduction during vital tooth preparation was the most common method, used by 42% of the respondents. Addition-cured silicone impression materials were the most frequently used impression material (78%). The surveyed practitioners were equally split between precious and non-precious metals as the substructure for indirect restorations. Glass-ionomer luting cements (47%) and resin-based cements (52%) were the most commonly used to cement porcelain fused to metal and zirconia indirect restorations, respectively. Laboratory made aesthetic veneers were prescribed by half of the respondents, while a third of them preferred direct resin composite as a veneer material. Conclusion: Within the limitations of the study, it was concluded that there has been an increase in the use of adhesive bonding and metal-free restorations. Amalgam and dentine pinscontinued to be used, contrary to international trends. Studies of the type reported are considered important in investigating trends and developments in dentistry.

Unintended changes to the occlusion following the provision of night guards.

A review of the literature on night guards left questions unanswered about the risk and possible causes of occlusal derangement linked to night guard design and use. Cases are presented where night guard use resulted in anterior open bite and associated occlusal derangement. The aetiology of the occlusal changes observed is discussed. It is concluded that adverse occlusal effects linked to the use of night guards may be found to be more common than anticipated from existing literature. Patient follow-up is essential to monitor the use and effects of night guards, and regardless of appliance type, unintended occlusal changes may result. The use and effects of partial coverage appliances require very careful monitoring. Suggestions are provided for information and written instructions to be given to patients provided with night guards and removable orthodontic retainers.

Reasons for placement and replacement of crowns in general dental practice.

Objectives: The aim of this study was to investigate the reasons for placement and replacement of crowns in general dental practice. Methods: Forty general dental practitioners recorded the principal reason for the provision of new (initial) and replacement crowns for a maximum of up to 20 patients over a 20-week period. Results: A total of 664 patients received 783 crowns during the period of this study. Of these, 69% (n = 542) were new (initial) placements and 31% (n = 241) were replacements. Overall, tooth fracture (45%, n = 241) was the most frequently reported reason for new/ initial crown placements. Aesthetics (21%, n = 53) and secondary/recurrent caries (20%; n = 47) were the most frequent reasons for crown replacement. Maxillary premolars (27%, n = 145) and mandibular molars (25%, n = 137) were the teeth that received most initial crown placements. In contrast, maxillary incisors (50%, n = 115) were the most common teeth to receive a replacement crown. Dentists were more likely to replace a crown if they had not placed the original crown: 74% of replacement crowns (n = 178) were placed by a different dentist. Most patients had only one crown placed or replaced per course of treatment (n = 611; 90%). Conclusions: The results of this study reveal the prescribing habits of dentists in relation to provision of initial and replacement crowns. The vast majority of patients had only one crown provided per course of treatment, which is probably a reflection of funding schemes and changing patterns of oral health. This sample reported fewer replacement crowns than previous studies. In keeping with existing literature, crowns were more frequently replaced when the treating dentist had not placed the initial crown. However, against this, more replacements were provided for more long-standing patients (5+ years attendance) compared to those with shorter attendance history (<5 years). In an area where high quality evidence is lacking, further consensus on the need for placement and replacement crowns is needed. Such information would assist dentists to provide high-quality care and commissioners in developing an evidence-based service.

Clinical studies in restorative dentistry: New directions and new demands.

Clinical research of restorative materials is confounded by problems of study designs, length of trials, type of information collected, and costs for trials, despite increasing numbers and considerable development of trials during the past 50 years. This opinion paper aims to discuss advantages and disadvantages of different study designs and outcomes for evaluating survival of dental restorations and to make recommendations for future study designs. Advantages and disadvantages of randomized trials, prospective and retrospective longitudinal studies, practice-based, pragmatic and cohort studies are addressed and discussed. The recommendations of the paper are that clinical trials should have rational control groups, include confounders such as patient risk factors in the data and analysis and should use outcome parameters relevant for profession and patients.

Upper anterior tooth dimensions in a young-adult Indian population in the UK: implications for aesthetic dentistry.

Introduction Knowledge of tooth dimensions and relationships and ethnic variations in these parameters are important in the planning and provision of aesthetic dentistry.Aim The aim of the present study was to investigate the dimensions and relationships of the upper anterior teeth in young adults of Indian origin, living in an urban location in the UK, and to compare the data obtained with data pertaining to other ethnic groups.Materials and methods This was a qualitative, non-experimental, cross sectional descriptive study with ethical approval. The dependent variables were tooth dimensions and relationships. The independent variable was gender. Fifty male and 50 female young adult Indians were recruited to the study, according to predetermined criteria. Upper and lower, full arch impressions were obtained for each of the 100 participants. Stone cast were obtained from these impressions. The width and length of each upper anterior tooth included in the casts were measured using precision callipers. Anterior arch length was determined using a flexible measuring tape. All measurements were repeated at least three times to obtain consistent values. The error of the method was investigated by means of repeat measurements. The data obtained was analysed, and compared with existing data on tooth dimensions and used to investigate the presence of Golden Proportion relationships.Results The measurements obtained had a normal distribution. Statistical analysis revealed significant differences in the overall data for left and right canine width and length (P <0.05). No such differences were noted in respect of the upper central and lateral incisors. Also, significant differences (P <0.05) were found to exist between male and female subjects in respect of the width of all anterior tooth types, except for the upper right lateral incisor. There were significant differences in the length of the upper left central incisor and upper right and left canines between male and female subjects (P <0.05). Significant differences (<0.05) were found in the width to length ratios between right and left canines. No such differences were observed for incisors. There was an absence of Golden Proportion relationships.Conclusion Within the limitations of the present study, it is concluded that it is inappropriate to adopt a formulaic, left/right symmetrical approach to smile design in the provision of aesthetic dentistry for young adults of Indian origin.

Dental witness seminars: dentistry in the UK since 1948.

Witness seminars attempt to get behind the scenes of advances and developments to find out what really happened at certain times; they are not intended to provide a detailed history of events. This paper presents highlights from the five John McLean Archive witness seminars, providing an instructional collection of memories and insights into the world of dentistry in the UK since the late 1940s. It is concluded that future change will be seen as a welcome constant to be used for the benefit of the profession and the patients and communities it serves.

What I wish I'd learned at dental school.

Background Much concern appears to exist as to the scope and content of contemporary dental school programmes, with the oft-cited criticism being made that dental graduates are 'no longer as good as they used to be'.Aim The aim of this project was to survey the views of dentists - both new graduates and more established practitioners - on aspects of their own dental school training they felt had been deficient as well as commenting on what aspects of dental school education they would like to see improved/enhanced in current times.Methods An invitation to complete an Internet-based questionnaire was emailed to the Fellows and Members of the Faculty of General Dental Practice (UK). Topics in the questionnaire included the respondent's own dental education history, how well they felt their dental school training had covered certain clinical and non-clinical topics; and their opinions on areas they felt should be included in contemporary dental school programmes.Results Six hundred and forty-nine responses were received from 3,348 emailed invitations (response rate = 19.4%). Sixty-one percent (395) of respondents were qualified for 10 years or more. Among clinical skills and techniques, a majority of respondents reported they felt they had not had sufficient teaching/training in dental school in surgical endodontics (76%), conscious sedation (72%), root surface debridement (71%), fixed orthodontic appliances (68%), porcelain veneers (63%), implants (56%) and posterior composites (53%). If designing a new dental school programme, the most common topics respondents would seek to include/increase were business and practice management (21%), communication skills (including patient management and leadership skills) (10%), and increased clinical time and experience (8%).Conclusions The findings of this project are of interest and relevance to those working with student dentists and young dental practitioners. A greater emphasis is needed on the teaching of certain non-clinical subjects such as business and communication skills, while within clinical subjects there is need to refine and expand teaching in identified areas such as exodontia and endodontics.

Influence of explorer tip diameter in identifying restoration margin discrepancies.

OBJECTIVES: Evaluations of the marginal adaptation of restorations in clinical trials rely on subjective assessments by evaluators. The purpose of the present study was to assess the use of dental explorers with different tip diameters to detect simulated marginal discrepancies. METHODS: Using three devices simulating vertical steps, horizontal gaps, and the combination of vertical and horizontal discrepancies and explorers with five different tip diameters, 10 experienced dental faculty members were asked to identify discrepancies at the boundary between Alfa (replacement unnecessarily) and Bravo (replacement questionable) ratings, according to modified United States Public Health Service criteria. RESULTS: A significant correlation was found between the tip diameters of the explorers and the Alfa/Bravo boundaries for the horizontal gaps, but not for the vertical steps. CONCLUSION: It was concluded that the tip diameter of dental explorers had no significant effect on the detection of vertical steps, but had a significant effect on the detection of horizontal gaps. The diagnosis of restoration marginal discrepancies and the rating of marginal adaptation in clinical trials may subsequently be found to be best achieved using techniques other than the probing of restoration margins.

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.

A cohort investigation of the changes in vocational dental practitioners' views on repairing defective direct composite restorations.

OBJECTIVE: To investigate changes in vocational dental practitioners (VDPs) views on repairing direct composite restorations (DCRs) during the vocational training (VT) year 2002-2003. DESIGN: A questionnaire-based cohort study. METHOD: Data on the repair of DCRs, including indications and details of operative techniques were collected by a questionnaire sent at the beginning of the VT year (September 2002) to all 12 Postgraduate Dental Deans in England. A follow-up questionnaire was sent to the Deans near the end of the VT year (May 2003). They were asked, on both occasions, to distribute the questionnaires among their VDPs and to return the completed questionnaires. RESULTS: Ten deaneries participated in the study. The September 2002 and May 2003 findings (306 respondents [66%] and 313 respondents [67%] respectively) were analysed using Chi-square statistic and t-test to identify any significant differences (P<0.05). Significant changes in the attitudes of the VDPs during the VT year included a shift to viewing reduction in treatment time (30% to 48%), cost to patient (12% to 20%) and the management of the partial loss of a restoration (57% to 70%) as indications for repairs. In contrast, there was a significant change in viewing secondary caries as an indication for repair (46% to 29%). In addition, there was a significant, worrisome shift in relation to the use of bonding systems and finishing instruments, together with a reduction in the anticipated longevity of composite repairs. CONCLUSION: Aspects of VDPs' attitudes to the repair of DCRs were found to change significantly during the VT year. Not all aspects of the changes observed were considered to be positive. Knowledge and understanding of repairs to DCRs need to be strengthened.

Contemporary dental practice in the UK: indirect restorations and fixed prosthodontics.

OBJECTIVES: To investigate, by questionnaire, the use and selection of materials and techniques for indirect restorations and fixed prosthodontics by dental practitioners in the North West of England and Scotland. METHODS: A questionnaire was sent to 1,000 general dental practitioners selected at random from dentists in Scotland and the North West of England. Non-responders were sent another questionnaire after a period of 4 weeks had elapsed. RESULTS: A total of 701 usable questionnaires were returned, giving a response rate of 70%. When selecting a material for the core build-up of vital teeth, practitioners used the following materials (%): amalgam (60), dual and light-cured resin composite (54), glass-ionomer cements (47), compomer (29) and resin-modified glass-ionomer cements (24). Where the use of a post was indicated indirect posts of both precious (67) and non-precious (37) alloys were preferred to prefabricated posts by the majority of practitioners for the restoration of root filled teeth. Direct titanium (14) and stainless steel (14) posts were not used extensively. Impression materials used by the practitioners were as follows: addition-cured silicone (70), condensation-cured silicone (20), polyether (9) and polysulphide (2). Traditional glass-ionomer cements (59) were used for the luting of single and multiple porcelain fused to metal units, with zinc phosphate and polycarboxylate cements (33) being the preferred alternatives. CONCLUSIONS: The majority of the practitioners surveyed in this study used: amalgam for core build-ups; indirect posts; addition-cured silicone for impressions; and glass-ionomer cements for luting procedures.

Contemporary dental practice in the UK: demographic data and practising arrangements.

OBJECTIVES: To investigate, by questionnaire, various aspects of primary dental care provision in the North West of England and Scotland. METHOD: A questionnaire containing 79 questions was sent to 1,000 practitioners, selected at random, in the North West of England and Scotland. Non-responders were sent another questionnaire after a period of 4 weeks had elapsed. RESULTS: Overall a response rate of 70% was achieved. The majority of practitioners were practice principals (65%), working in a group NHS practice (80%) located in a city or town centre (49%). On average 10-20 patients were treated each session with fewer patients treated per session under private arrangements. Many practitioners were found to lack hygienist support (44%) and to employ unqualified dental nurses (82%). Younger practitioners were more likely than senior colleagues to have access to up-to-date computers whilst 37% and 74% of respondents never used CAL programmes or magnification respectively. Contemporary cross-infection control standards were used by the majority of practitioners, although 3% of practitioners reported only autoclaving their handpiece once a day. CONCLUSIONS: The majority of practitioners, involved in this study, worked under National Health Service (NHS) regulations as principals in a group practice where the workload was greater than the private/independent sector. Contemporary cross-infection procedures were used routinely. In contrast computer-aided learning programmes and magnification were not used routinely. The practitioners in this study employed significant numbers of unqualified dental nurses.