The Accuracy of Dental Students and Dentists Assessing the Total Occlusal Convergence of Crown Preparations.

This study examined the ability of dental students and qualified dentists to visually assess the total occlusal convergence of clinical crowns. 10 working casts of maxillary molar crown preparations were installed in phantom heads in a clinical skills laboratory. 87 participants assessed the buccolingual and mesiodistal total occlusal convergence of the casts. 2nd-year students with no experience in fixed prosthodontics served as a control group with 3rd, 4th and 5th-year students and qualified dentists including specialists in restorative dentistry involved. Differences were calculated between the measured angles and the subject's estimate to assess accuracy. For 8 of the 20 surfaces measured there were significant differences. (p ⟨ 0.05). Differences were not standardized between the groups, with no clear patterns of difference in tooth type or aspect assessed. Differences were primarily between the control group and the more experienced groups. The remaining groups were of similar ability. A minority of participants in each group were highly divergent from their peers. This study found significant differences between participants with no experience of fixed prosthodontics and those with experience, however, the ability to assess total occlusal convergence does not appear to improve significantly with experience.

Adequately Prepared? A Study Using an Innovative Computer Application to Measure Clinical Crown Convergence Angles Achieved by Students at a UK Dental School.

This study examined the total occlusal convergence angles created for full coverage crown preparations by students at a UK dental school. Working casts of 82 clinical crown preparations were scanned using a 3D scanner. Stereolithographic files were uploaded to Preppr, a crown preparation analysis application. Mean bucco-lingual convergence angle were 19.6° (+/-11.7) and mesial-distally 17.8° (+/-11.1). Smallest bucco-lingual convergence angles were achieved for canine teeth with the largest on molar teeth. The smallest mesio-distal values were on canine teeth with the largest on molar teeth. Ideal total convergence angles (4-14°) were achieved in 23% of bucco-lingual preparations and 33% of mesio-distal preparation. Results for clinically acceptable angles (10-20°) were 30% and 40% respectively. There were no statistically significant differences between tooth types for mean bucco-lingual values. (p=0.623), mesio-distal mean values were statistically different by tooth type (p=0.003). Mean values for mandibular molars were significantly higher than for maxillary incisors (p=0.001) and mandibular molars had significantly higher values than maxillary canines (p=0.045). Results in this study were comparable to those of other students and qualified clinicians, with a minority of preparation achieving ideal values.

Effect of Luting Cement Space on the Strain Response of Gold Crowns Under Static Compressive Loading.

The aim the work was to investigate the effect of varying degrees of luting cement thickness on the strain of the cemented gold alloy crowns under compression. Five dies with their corresponding crowns were fabricated using a lost wax technique. Three gold crowns for each die were fabricated under the control of specific die spacer layers to provide a space of 40 µm (10 layers of die-spacer thickness) and 80 µm (20 layers of die-spacer thickness). The crowns were subsequently cemented using zinc phosphate cement. The crowns were subjected to gradual static compressive loading between 10N to 250N (Newton) and the strain measured simultaneously. The results were statistically analysed using Independent t-test for the different die-spacer thickness at the 95% confidence interval (p = 0.05). It was found that a significant relationship in the three thicknesses. It was concluded that the absence of die-spacer significantly reduced strain response, whereas a very little change in the strain recorded as the die spacer layers has increased. Clinically, decreasing the number of die-spacer layers is advantageous as it provides a lower strain response under static compressive loading that would improve the longevity of the cemented full crowns inside the patient's mouth.

The impact of General Dental Council registration and continuing professional development on UK dental care professionals: (2) dental technicians.

OBJECTIVE: To investigate the impact of General Dental Council (GDC) registration and mandatory CPD on dental technicians' views, job satisfaction and intention to leave the profession. DESIGN: Postal/online survey, conducted in parallel with a survey of dental nurses. SETTING: UK private and NHS practices, community services, dental hospitals. SUBJECTS AND METHODS: Representative sample of GDC registrants. MAIN OUTCOME MEASURES: job satisfaction; intention to leave profession (dependent variable in regression analysis). RESULTS: 605 were sampled: 40 were ineligible (left the register in July 2011, re-qualified in another dental care profession, shared a practice address with another selected DT); 193 responded (response rate 34%). 22% were female (mean age 38.2 years) and 78% male (mean age 49.4 years). The general principle of registration was endorsed by 52%, and compulsory registration by 54%, but the fee level by only 13%. Most technicians felt that registration had had either no effect or a negative effect on their view of their career (80%), role (78%) or status within the dental team (85%), and 66% did not agree that training helped them to do their job better. Fifty-one percent were not satisfied with their job and 20% intended to leave the profession. Intention to leave was predicted by greater dissatisfaction with remuneration. CONCLUSIONS: Criticisms regarding the cost and relevance of registration and the cost, relevance and accessibility of CPD, coupled with potentially high level of attrition from the profession, suggest a review of the fee and salary structure and greater support for CPD is warranted.

The impact of General Dental Council registration and continuing professional development on UK dental care professionals: (1) dental nurses.

OBJECTIVE: To investigate the impact of GDC registration and mandatory CPD on dental nurses' views, job satisfaction and intention to leave. DESIGN: Postal/online survey, conducted in parallel with a survey of dental technicians. SETTING: UK private and NHS practices, community services, dental hospitals. SUBJECTS AND METHODS: Representative sample of General Dental Council registrants. MAIN OUTCOME MEASURES: Job satisfaction; intention to leave profession (dependent variable in regression analysis). RESULTS: Eleven were ineligible (left profession, moved abroad); 267 (44% of those eligible) responded, all female. Respondents' mean age was 38.2 years (sd 10.74). The general principle of registration was endorsed by 67%, and compulsory registration by 51%, but the fee level by only 6%. Most nurses did not feel that registration had affected their view of dental nursing as a career (56%), their role (74%) or status (86%) within the dental team, or that CPD helped them to do their job better (76%). Fifty-six percent were not satisfied with their job, and 22% intended to leave the profession. Intention to leave was predicted by younger age and greater dissatisfaction with physical working conditions and opportunities to progress. CONCLUSIONS: Widely held criticisms regarding the costs and relevance of registration and CPD coupled with a potentially high level of attrition from the profession suggest a review of the fee and salary structure and greater financial support for CPD is warranted.

Dental hygienists and therapists: how much professional autonomy do they have? How much do they want? Results from a UK survey.

OBJECTIVES: To investigate autonomous working among singly and dually qualified dental hygienists and therapists in UK primary care. Earlier studies and policy papers suggest that greater autonomy for these groups may be a desirable workforce planning goal. METHODS: UK-wide postal surveys of hygienists, hygienist-therapists and therapists. Respondents were asked whether they undertook 15 clinical activities on their own initiative, how comfortable they would feel undertaking such clinical activities if referral from a dentist were not required, and how they perceived dentists' reactions. RESULTS: Overall response rate was 65% (n = 150 hygienists, 183 hygienist-therapists and 152 therapists). Over 80% of hygienists and hygienist-therapists reported undertaking BPEs, history-taking, pocket charting, mucosal examinations and recall interval planning autonomously. Similarly high proportions of hygienist-therapists and therapists reported giving local analgesia and choosing restorative materials autonomously. However, fewer than 50% of all three groups said they undertook dental charting, fissure sealing, resin restorations, taking radiographs, and tooth whitening autonomously. While confidence in undertaking such activities without a dentist's referral was generally high, it was lower in respect to mucosal examinations, identifying suspicious lesions, interpreting radiographs, tooth whitening, and (except for singly qualified dental therapists) diagnosing caries. CONCLUSIONS: Results suggest high levels of experience and confidence in their ability to work autonomously across a wide range of investigative activities, treatment decision-making and treatment planning. The exceptions to this pattern are appropriate to the different clinical remit of these groups.

Job satisfaction among dually qualified dental hygienist-therapists in UK primary care: a structural model.

OBJECTIVE: To investigate job satisfaction among hygienist-therapists. Increasing numbers of hygienist-therapists work in UK primary dental care teams. Earlier studies suggest a clinical remit/clinical activity mismatch, without investigating any link with job satisfaction. METHODS: A UK-wide survey of dental hygienist-therapists using a random sample of the General Dental Council Register of Dental Care Professionals. Factors associated with job satisfaction (measured by the Warr-Cook-Wall ten-dimension scale) were entered into a series of multiple regression analyses to build up a path model. RESULTS: Analysis was undertaken on 183 respondents (response rate: 60%). Mean score for overall satisfaction was 5.36 (SD 1.28) out of a range of 1-7. Multiple regression analysis confirmed the following direct predictors of overall job satisfaction: satisfaction with colleagues, remuneration, variety of work; rating of hygiene work as rewarding; and not being self-employed (R(2) = 0.69). Satisfaction with variety of work was the strongest predictor, itself strongly predicted by the extent the clinical remit was undertaken. Dentists' recognition of their remit, quality of clinical work and qualifications had a strong indirect effect on overall job satisfaction. CONCLUSIONS: The study suggests both greater use of the therapy skills these individuals possess, and better recognition of their remit, qualifications and quality of work by their dentist colleague, may be linked to higher job satisfaction. The implications for the policy of greater team working in dental primary care are discussed.

Decisions about restorative dental treatment among dentists attending a postgraduate continuing professional development course.

Continuing professional development (CPD) courses seek to inform, educate and develop practitioners' patterns of prescribing in line with the evidence base. When devising such courses it would be useful for organisers to have some idea of what current practice is and the decision-making process as this would inform the development of appropriate continuing education courses. A questionnaire comprising ten questions was given to 90 dentists at the start of a day's lecture course run under Section 63 regulations. The dentists were then shown a series of pictures and asked how they would manage each of the cases presented. Eighty-nine dentists completed the questionnaire and the results were tabulated and fed back to the group at the end of their day's course. Results showed varied and inconsistent application of advances in restorative techniques among the respondents. Despite a definite interest in more modern treatment options, many practitioners continued to support the use of traditional techniques that could be considered outdated. Further investigation of the practices of GDPs and their decision-making processes would be useful in targeting postgraduate education programmes to encourage the uptake of evidence-based practice.

The impact of teamworking on the knowledge and attitudes of final year dental students.

AIMS: To relate final year UK dental undergraduates' experience of teamwork-related training to their knowledge of the clinical role of dental hygienist-therapists, and their views of the clinical roles of dental care professionals. METHODS: A postal questionnaire was sent to the ten UK dental schools which had agreed to participate. Analysis was based on standard non-parametric statistical tests. RESULTS: Of the 705 final year students in the ten schools, 358 (51%) returned questionnaires. Numbers from each school ranged from 79 to 6 (mean 35.8). Eighty-nine percent of students reported receiving information on roles of dental team members; 61% had experienced joint teaching sessions with DCPs; 53% had shared clinical treatment of patients with student hygienists or hygienist-therapists. Thirty-two percent of respondents had experienced all three elements. Views on this experience were generally positive, particularly in relation to shared clinical treatment sessions. Students who had received such training were more knowledgeable about the clinical remit of dental hygienist-therapists. However, training experience was not related to their views on the appropriate clinical activity of DCPs which tended to be dentist-centric even for many procedures within the legal remit of hygienists and hygienist-therapists. CONCLUSIONS: The study suggests that acceptance of non-dentists providing patient care lags behind the comparable situation within the primary care medical team. If we are to succeed in the delivery of a modernised dental care system, it is crucial that dental education promotes awareness and acceptance of the professional status and ability of DCP colleagues.

Changing clinicians' behavior: a randomized controlled trial of fees and education.

The fissure-sealing of newly erupted molars is an effective caries prevention treatment, but remains underutilized. Two plausible reasons are the financial disincentive produced by the dental remuneration system, and dentists' lack of awareness of evidence-based practice. The primary hypothesis was that implementation strategies based on remuneration or training in evidence-based healthcare would produce a higher proportion of children receiving sealed second permanent molars than standard care. The four study arms were: fee per sealant treatment, education in evidence-based practice, fee plus education, and control. A cost-effectiveness analysis was conducted. Analysis was based on 133 dentists and 2833 children. After adjustment for baseline differences, the primary outcome was 9.8% higher when a fee was offered. The education intervention had no statistically significant effect. 'Fee only' was the most cost-effective intervention. The study contributes to the incentives in health care provision debate, and led to the introduction of a direct fee for this treatment.

Occlusal convergence and strain distribution on the axial surface of cemented gold crowns.

The overall thrust of this work is concerned with the performance of the adhesives used to simulate cementation of gold crowns onto nickel chromium dies under static and dynamic compression. A measurement system, based on the mounting of strain gauges on the outer surface of the crowns, has been developed allowing an indirect semi-quantitative estimate of the state of adhesion. This paper reports an investigation of the effect of increased total occlusal convergence (TOC) of the nickel chromium dies from 12 degrees to 24 degrees with different degrees of cementation, a) un-cemented, b) partially cemented and c) fully cemented. Four nickel chromium dies (12 degrees TOC) and five nickel chromium dies (24 degrees TOC) for each convergence were fabricated using the lost wax technique. The axial height of all dies was 6mm. Two miniature gauges were installed on opposing axial surfaces of each gold crown 1 mm above the crown margin. Axial loading and unloading of the crowns was repeated five times for each crown and the values for strain recorded. The results showed an increase in strain at the axial surfaces with increasing TOC, providing useful design information for the durability of restorative crowns. These findings, along with the findings of earlier work are consistent with a simple model of load transfer between the crown and the die.

Activity and education of clinical dental technicians: a UK survey.

AIMS: This survey aimed to determine the clinical activity of clinical dental technicians (CDTs) in the UK and to establish their employment status, views of statutory registration and need for further education. Until 2006, this practise was illegal in the UK. MATERIALS AND METHODS: A postal questionnaire was sent to 128 members of the Clinical Dental Technicians' Association (CDTA) who had agreed to participate in this study. Analysis was conducted using standard non-parametric statistical tests and quantitative techniques. RESULTS: A response rate of 54% was achieved. Qualifications in clinical dental technology from George Brown College, Toronto, Canada were held by 68%, with 16% currently undergoing training and 16% neither qualified nor in training. The majority (90%) owned a laboratory with 61% stating they had between one and four dental surgeries on site. CDTs with Canadian qualifications tended to provide a wider range of procedures, coupled with patient lists and recall systems, compared to those not so qualified. Eighty-one percent welcomed the prospect of statutory registration with 82% indicating that it would enhance their professional profile. CONCLUSIONS: This small but significant survey gives some insight of the work which has been undertaken by CDTs for many years, albeit illegally. With appropriate training and education, and consequent GDC registration, CDTs will be in a position to make a positive contribution to the clinical care of patients.

The acceptability of dually-qualified dental hygienist-therapists to general dental practitioners in South-East Scotland.

AIMS: Recent UK legislation allows dental therapists or jointly-qualified dental hygienist-therapists to work in the general dental service. This study aimed to investigate the extent of dentists' knowledge of the clinical remit of jointly qualified hygienist-therapists, their willingness to consider employing such a professional, and factors associated with these two measures. MATERIALS AND METHODS: A postal questionnaire was sent to 616 NHS-registered dentists in South-East Scotland. Analysis and classification of responses to open-ended questions used standard non-parametric statistical tests and quantitative techniques. RESULTS: Following two mailings, a 50% (n = 310) response rate was obtained. A total of 65% of dentists worked in a practice employing a dental hygienist, while only 2% employed a dental therapist. Hygienists tended to work in larger practices. Dentists' knowledge of the clinical remit of the dually-qualified hygienist-therapist was found to be limited, reflecting a restricted and inaccurate view of the professional remit of a hygienist-therapist. The majority (64%) said they would consider employing a hygienist-therapist in their practice, rising to 72% amongst dentists already working with a hygienist. Reasons given by dentists who were negative about this prospect were sought. Those who worked with a hygienist tended to refer to lack of physical space, whilst those who did not tended to cite reservations on clinical skills, competence and responsibilities, or on the costs involved. CONCLUSIONS: This study identified considerable ignorance and negativity among dentists about the nature and clinical remit of this group of professionals. Dually-qualified hygienist-therapists will be in a position to treat much of the routine disease that exists within the population, and dentists may benefit from education in relation to the substantial contribution these individuals could potentially make to patient care.

Educational needs and employment status of Scottish dental nurses.

OBJECTIVE: To investigate the educational needs and employment status of dental nurses in Scotland. SUBJECTS: One thousand, seven hundred and thirty dental nurses with postal addresses in Scotland. DESIGN: Structured questionnaire. RESULTS: A 65% response rate was achieved following three mailings. The majority of respondents were employed in the central belt of Scotland although comparatively, substantial numbers were also recorded as being employed in Highland and Grampian regions. A total of 70% of dental nurses stated they were in full-time employment, with 74% of all participants reporting they were qualified. Of those who were unqualified, 17% (n = 191) were not in the process of formal training which may mean they are unable to work in the future, unless they conform to the GDC 'grandparenting' requirements. Induction training had only been received by 34% (n = 377) of this group, and a mere 21% (n = 234) reported regular CPD involvement. Of the 75% (n = 832) who responded to a question on funding for CPD, only 50% (412) received financial assistance. Geographical location for many nurses generated a number of difficulties in accessing education, and the possibility of distance or e-learning was requested by 65% of the sample. CONCLUSIONS: This study demonstrates clearly that there are many well-qualified dental nurses in employment in Scotland. However, unless structured career pathways are developed, access to education is simplified, and the problem of poor remuneration is addressed, then foreseeable problems may arise where there is insufficient enticement to encourage people to join what is an already underpopulated profession.

Compressive stress-strain behaviour of cast dental restorations in relation to luting cement distribution.

This work is concerned with the performance, under dynamic compression, of the adhesives used to simulate cementation of gold crowns onto nickel chromium dies. A measurement system, based on the mounting of strain gauges onto the outer surface of the crowns, has been developed, which allows a semi-quantitative estimate of the state of adhesion. A preliminary study was carried out where miniature gauges were bonded onto the buccal, lingual, mesial and distal surfaces of gold crowns cast to fit onto a chromium-cobalt die, as a precursor to the final design of the instrumented crown. The crowns were then loaded in compression periodically measuring the strain at all four gauges. The results showed the load-strain relationship in fully, partially and uncemented crowns, along with repeated load-unload behaviour to close to the ultimate strength of the bond. The load-strain relationship is linear and repeatable and the slope varies over a factor of about 30 between the un-cemented and fully cemented crown, demonstrating that there is significant sensitivity to bond integrity. These results were used to determine the parameters for a systematic study of S-N relationships in restorative dentistry crowns.

A radiographic method of estimating surface area of amalgam restorations.

UNLABELLED: Mercury released from the surface of amalgam fillings has been linked to a variety of disorders, but without proof of correlation. Studies use surface counts to estimate this variable, but large-scale studies would require a tool to rapidly and accurately assess restoration surface area. OBJECTIVES: This study investigated digital analysis of conventional dental radiographs as a means of estimating amalgam surface area. METHODS: Amalgam fillings were placed in 40 typodont teeth, the surface areas of the restorations were determined by measuring standardized photomicrographs of each surface. The teeth were radiographed, and area of the radiographic image of the restorations was measured. Data were used to produce expressions to estimate actual area from radiographic area. RESULTS: Regression analyses showed that surface area estimation from radiographic area was more accurate than estimation from surface counts. The accuracy of the surface area count was further improved by combining the radiographic area with a photographic occlusal area measurement or surface count, the latter giving the highest correlation. CONCLUSIONS: This study demonstrated that two-dimensional dental radiographs may be used to estimate surface area of amalgam restorations.

A radiographic review of bone levels around Calcitek dental implants supporting mandibular over-dentures. Preliminary results at 3 to 6 years.

This retrospective study aimed to measure marginal bone resorption around cylindrical hydroxyapatite-coated implants retaining mandibular overdentures and compares this between two- and four- implant supported overdentures. Twenty three edentulous patients received 66 implants in their anterior mandible and were restored with overdentures. Panoramic radiographs one week post-operatively and at last recall were compared and marginal bone loss calculated. The mean recall interval was 51.22 months. The mean cumulative bone loss was 1.08 mm and the mean annual bone loss 0.263 mm. There was no significant difference between two- and four- implant overdentures. The results were comparable with other reports.

Educational needs and employment status of Scottish dental technicians.

OBJECTIVE: To investigate the educational needs and employment status of dental technicians in Scotland. SUBJECTS: Two hundred and fifty dental technicians with postal addresses in Scotland. DESIGN: Structured questionnaire. RESULTS: An 83% response rate was achieved following three mailings. The majority of respondents were employed in commercial dental laboratories largely within the 'central belt' of Scotland, with 96% stating they were in full-time employment. Only 33% of these essential health-care workers were voluntarily registered with the Dental Technicians' Association, suggesting that a significant number had not felt it necessary or beneficial to do so. A lack of educational structure was identified, as was poor remuneration and an absence of opportunity for career progression. Although the prospect of continuing professional development was desirable, many respondents reported that they would be penalised financially for undertaking this and, in addition, may not be given the opportunity to pursue education because of lack of co-operation from their employer. Only 47% had attended an educational event within the preceding year, and of those who had not done this, a period of two-32 years had elapsed since any CPD involvement. Of the respondents, only 34% stated that any financial assistance had been available for educational purposes, with access to education being highlighted as problematic by 68%. A total of 64% of subjects felt they were out-of-date with professional education. CONCLUSIONS: This study highlights a number of real and potential problems in the field of education in dental technology. It is apparent that change within the structure of education and professional status, although largely welcomed, may be difficult to implement. The profession, as a whole, must realise that these changes in education and employment are not optional, and should be embraced as a positive step which will hopefully raise the profile and status of dental technicians throughout the UK.

Educational needs and employment status of Scottish dental hygienists.

AIMS AND OBJECTIVES: To investigate the educational needs and employment status of registered dental hygienists in Scotland. SUBJECTS: Three hundred and eighty one registered dental hygienists with postal addresses in Scotland. DESIGN: Structured questionnaire. RESULTS: A 76% response rate was achieved following two mailings. Of the respondents, 43% were in full-time employment albeit in more than one setting, mostly in the 'central belt' of Scotland. It was reported that 41% were employed in general dental practice with both NHS and private lists and 39% worked in a purely private setting. The introduction of extended clinical duties had been well received and 59% of subjects were interested in additional training in dental therapy, should this become available. Absence of funding for CPD was raised repeatedly, with only 41% reporting a degree of financial assistance. Greater accessibility to continuing education via distance learning, particularly in remote and rural settings, was requested by 73% of hygienists. CONCLUSIONS: This study identifies a number of issues in relation to this increasingly important group of healthcare professionals, which will inform the providers of oral healthcare. Although hygienists' involvement in CPD was commendable, results indicated that despite commitment to their profession, respondents did not always feel respected in terms of their employment status or support for continuing professional development.