Academic Centre For Dentistry Amsterdam Research Articles

Haptic simulators with virtual reality environments in dental education: A preliminary teaching diagnosis

A descriptive exploratory study was performed at the Universidad Europea in Madrid with a sample of 22 professors of dentistry with a distinguished career in simulation. A community of practice of was created for collaborative learning using the Simondont® Dental Trainer, a dental training simulator developed by Moog and the Academic Centre for Dentistry Amsterdam (ACTA) that combines haptic and virtual reality interfaces. A post-experimental questionnaire was administered to assess the performance of the Simondont® and to determine whether or not the professors would be willing to incorporate it into their curriculum. IBM SPSS Statistics V21.0 software was used for the data analysis and statistics of mean, standard deviation and correlation of the results. Tables and box plots were developed applying Kolmogorov-Smirnov and Kruskal-Wallis tests, with a level of significance of ?=0.05. The results indicated that the educational contributions of the Simodont® exceeded its technical features. In addition, an inverse relationship was described between the variables Age and Ease of use of the simulator. It became apparent that the use of state-of-the-art technology begins to decrease as teaching age increases. This indicated the need to train faculty in the use of the technology and in the introduction of innovative teaching methods to make the best use of the basic and additional opportunities the simulator offers.

Corrigendum

Rosier BT, van Loveren C, Zaura E, Loos BG, Keijser BJF, Crielaard W, Lagerweij MD. 2017. Caries incidence in a healthy young adult population in relation to diet. JDR Clin Trans Res. 2(2):142-150. (Original DOI: 10.1177/2380084416683340)This article was printed in the April 2017 issue of the JDR Clinical & Translational Research with the fourth author, B.G. Loos, omitted. The online version of this article has been corrected to accurately reflect B.G. Loos’s authorship: Dr. Loos’s name was added as the fourth author in the byline, his affiliation was added to the footnotes (Department of Periodontology, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije University Amsterdam, Amsterdam, The Netherlands), and his contributions were added to the Author Contributions at the end of the article.

Periodontitis is an independent risk indicator for atherosclerotic cardiovascular diseases among 60 174 participants in a large dental school in the Netherlands

BackgroundThe association between periodontitis and atherosclerotic cardiovascular diseases (ACVD) has been established in some modestly sized studies (<10 000). Rarely, however, periodontitis has been studied directly; often tooth loss or...

Biomimetic calcium phosphate bone substitute for bone tissue engineering

Event Abstract Back to Event Biomimetic calcium phosphate bone substitute for bone tissue engineering Yuelian Liu1, Tie Liu1, Daniel Wismeijer1 and Klaas De Groot1 1 VU University, Department of Oral Implantology and Prosthetic Dentistry, Academic Centre for Dentistry Amsterdam, Netherlands Introduction: The treatment of bone defects requires adequate volume of bone tissue, which is of paramount importance to achieve an excellent aesthetic and functional restoration. Synthetic calcium phosphate (CaP) biomaterials are widely used in the regeneration of bone defects because of their chemical similarity to native bone tissue. Currently, there is an increased interest in biomimetic calcium-phosphate materials because of their capacity to delivery bioactive agents (BMP-2) without compromising their bioactivity[1],[2]. As a synthetic alternative to autologous bone grafting, a biomimetic calcium phosphate bone substitute (BioCaP) was developed with two protein delivery modes: 1) protein in the interior of BioCaP (internally-incorporated mode), 2) protein in the coating on the surface of BioCaP (coating-incorporated mode). The aim of this study is to evaluate the osteoinductivity of BioCaP with each delivery mode of BMP-2, and to investigate the therapeutic effectiveness of BioCaP in the repair of a large cylindrical bone defect (8mm in diameter and 13mm in depth) in sheep. Materials and Methods: In an ectopic rat model: To evaluate the osteoinductivity of materials, granules of BioCaP with different carrying modes of BMP-2 were implanted subcutaneously in rats. Samples were collected after five weeks for histomorphometric analysis. Two experimental and three control groups were analyzed (n=6 rats per group). The groups were: (1) BioCaP granules with internally-incorporated BMP-2); (2) BioCaP granules with coating-incorporated BMP-2; (3) BioCaP granules with adsorbed BMP-2; (4) BioCaP granules without a CaP coating or BMP-2; and (5) BioCaP granules with a CaP coating but no BMP-2. In an orthotopic sheep model: To investigate the therapeutic effectiveness of BioCaP with each delivery mode of BMP-2 in the repair of a large cylindrical bone defect (8mm in diameter and 13mm in depth) in sheep, six groups were established: (1) BioCaP only; (2) BioCaP with coating-incorporated BMP-2; (3) BioCaP with internally-incorporated BMP-2; (4) no graft material (negative control); (5) autologous bone (positive control); (6) deproteinized bovine bone (DBB, a commercial product as control). 4 and 8 weeks after implantation, samples were withdrawn for histological and histomorphometric analysis. Results: In vivo data showed that the volume densities of bone, bone marrow, and blood vessels were significantly higher in samples where BMP-2 was incorporated internally or in the coating compared with granules with adsorbed growth factor. BioCaP with BMP-2 showed equal efficacy as autologous bone in the bone defect repair at 8 weeks post-implantation. Both delivery modes of BMP-2 accelerated the bone formation in an early period of 4 weeks. The internally-incorporated mode enhanced bone formation after 8 weeks, showing more efficient than DBB. Within 8 weeks, about half of BioCaP with either internally-incorporated BMP-2 or without BMP-2 was degraded, which was significantly higher than that of BioCaP with coating-incorporated BMP-2. Conclusions: In conclusion, biomimetic calcium phosphate bone substitutes enhance bone formation. Benefiting from these results, BioCaP can be a promising alternative to the autografts for bone tissue engineering. The autologous bone will not be needed clinically in the near future.

The evolution of thinking about temporomandibular pain

Every dentist has observed the fact that pain symptoms and responses are different among the patients in his or her practice. This is especially true for patients who seek treatment for temporomandibular disorders (TMD), because some of these patients do well when appropriately treated, whereas others continue to have pain. Also, some patients in the latter group may have other somatic pain symptoms that are accompanied by psychological symptoms such as anxiety and depression. What is the most likely explanation for these differences? Dr. Visscher is a physical therapist and epidemiologist, an associate professor, and chair, Department of Oral Kinesiology, Academic Centre for Dentistry Amsterdam, Gustav Mahlerlaan 3004, 1081 LA Amsterdam, The Netherlands. Dr. Lobbezoo is a professor, chair, and vice dean, Department of Oral Health Sciences, Academic Centre for Dentistry Amsterdam, Amsterdam, The Netherlands.

Risk of bleeding after dentoalveolar surgery in patients taking anticoagulants

To avoid increasing the risk of thromboembolic events, it is recommended that treatment with anticoagulants should be continued during dentoalveolar operations. We have evaluated the incidence of bleeding after dentoalveolar operations in a prospective study of 206 patients, 103 who were, and 103 who were not, taking anticoagulants. Seventy-one were taking thrombocyte aggregation inhibitors and 32 vitamin K antagonists. Patients were treated according to guidelines developed at the Academic Centre for Dentistry Amsterdam (ACTA), The Netherlands. The operations studied included surgical extraction (when the surgeon had to incise the gingiva before extraction), non-surgical extraction, apicectomy, and placement of implants. Patients were given standard postoperative care and those taking vitamin K antagonists used tranexamic acid mouthwash postoperatively.No patient developed a severe bleed that required intervention. Seven patients (7%) taking anticoagulants developed mild postoperative bleeds. Patients taking vitamin K antagonists reported 3 episodes (9%) compared with 4 (6%) in the group taking thrombocyte aggregation inhibitors. Among patients not taking anticoagulants, two (2%) developed mild bleeding. The differences between the groups were not significant. All bleeding was controlled by the patients themselves with compression with gauze. We conclude that dentoalveolar surgery is safe in patients being treated with anticoagulants provided that the conditions described in the ACTA guidelines are met.

Bisphosphonates differently affect jaw and long-bone marrow cells

Time (months) TR AC P + M NC s/ cm 2 Bisphosphonates differently affect jaw and long-bone marrow cells Jenny A.F. Vermeer1, Ineke D.C. Jansen1,2, Greetje A.P. Renders1, Teun J. de Vries1,2, Vincent Everts1 Departments of 1Oral Cell Biology & Functional Anatomy and 2Periodontology, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and VU University Amsterdam, MOVE Research Institute Amsterdam, Amsterdam, The Netherlands

Satisfaction with orthodontic treatment.

To examine the satisfaction of patients with their orthodontic treatment at the Department of Orthodontics at the Academic Centre for Dentistry Amsterdam (ACTA) in The Netherlands. To analyze differences in satisfaction through time, the results of patients treated at ACTA in 2008 and 2009 were compared with the results of patients treated at ACTA in 2000. A validated questionnaire about patient satisfaction was used. The total scale was divided into six subscales. A questionnaire was sent to all patients younger than 30 years who finished orthodontic treatment in 2008 and 2009 at ACTA. The internal consistency of the total scale and the six subscales of the questionnaire was satisfactory. Respondents scored highest on items about satisfaction with the doctor-patient relationship (mean 4.24; SD 0.63) and lowest on items regarding their satisfaction with psychosocial improvement (mean 2.88; SD 0.87). Compared to the results of the sample from 2000, significant differences were found on the subscales doctor-patient relationship, residual category, and psychosocial improvement as well as on the total sum scale. The doctor-patient relationship remains the most important factor contributing to patient satisfaction. However, the results show that, overall, patients are more satisfied with their orthodontic treatment than patients were a decade ago.

Satisfaction with orthodontic treatment.

Abstract Objectives: To examine the satisfaction of patients with their orthodontic treatment at the Department of Orthodontics at the Academic Centre for Dentistry Amsterdam (ACTA) in the Netherlands. Materials and Methods: To analyze differences in satisfaction through time, the results of patients treated at ACTA in 2008 and 2009 were compared with the results of patients treated at ACTA in 2000. A validated questionnaire about patient satisfaction was used. The total scale was divided into six subscales. A questionnaire was sent to all patients younger than 30years who finished orthodontic treatment in 2008 and 2009 at ACTA. Results: The internal consistency of the total scale and the six subscales of the questionnaire was satisfactory. Respondents scored highest on items about satisfaction with the doctor-patient relationship (mean, 4.24; SD, 0.63) and lowest on items regarding their satisfaction with psychosocial improvement (mean, 2.88; SD, 0.87). In contrast to the sample from 2000, gender was no significant predictor of patient satisfaction. The results showed significantly lower values on overall satisfaction and on all subscales, with only one exception. On the subscale psychosocial improvement, females in the present study had similar scores to females in 2000. Conclusions: The doctor-patient relationship remains the most important factor contributing to patient satisfaction. However, the results show that, overall, patients are less satisfied with their orthodontic treatment than patients were a decade ago and that gender differences no longer predict patient satisfaction.

Professioneel gedrag in het tandheelkundeonderwijs

The professional behaviour of future dentists is an important topic in dental curricula. Aspects of professional behaviour are, among other things: being respectful to patients, putting the interest of the patients first, reliability, integrity, and knowing one's professional limitations and acting according to them when treating patients. Throughout the curriculum students receive feedback on their functioning with regard to professional behaviour and are also examined on those points. At the programme at the Academic Centre for Dentistry Amsterdam, experience has been gained in recent years in addressing and evaluating (un)professional behaviour among students.

Functional Foods: Towards Improving Oral Health

Functional Foods: Towards Improving Oral Health

The Anticaries Effect of a Food Extract (Shiitake) in a Short-Term Clinical Study

The main objective was to investigate whether low-molecular-weight fraction of edible mushroom shiitake extract (Lentinus edodes) possesses caries-preventive properties. The study was designed as a double-blind, three-leg, cross-over, randomized, controlled clinical trial carried out on two series of volunteers at the University of Gothenburg, and the Academic Centre for Dentistry Amsterdam. Volunteers rinsed twice daily with a solution containing low-molecular-weight fraction of edible mushroom, placebo (negative control without active ingredients), or Meridol (positive control, AmF-SnF2) for two weeks, with a two-week washout period between each rinsing period. Changes in the acidogenicity of dental plaque before and after a sucrose challenge, shifts in microbial composition, and plaque scores were determined. Frequent rinses with shiitake reduced the metabolic activity of dental plaque. No reduction of plaque scores and no inhibition of the production of organic acids in plaque was found. Minor differences in microbial composition between test sessions were found. To conclude, the results indicate that shiitake extract has anticariogenic potential, but not to the same extent as the positive control.

Developing abbreviated OHIP versions for use with TMD patients

The aim of this study was to evaluate the psychometric characteristics of three versions of the Dutch Oral Health Impact Profile (OHIP-NL), for clinical use with temporomandibular disorder (TMD) patients. To that end, two abbreviated OHIP versions (OHIP-NL14 and OHIP-NL5) were developed by respectively selecting 14 and five items from the officially translated and culturally adapted original 49-item OHIP-NL questionnaire. A total of 245 consecutive patients, referred by their dentist to the TMD clinic of the Academic Centre for Dentistry Amsterdam (77% women; mean age ± s.d. = 41·0 ± 14·9 years), completed the Research Diagnostic Criteria for TMD (RDC/TMD) axis II questionnaire and the OHIP-NL. Reliability and validity of all three OHIP versions were compared, and their associations with four psychological axis II variables, indicating the level of impairment of patients with TMD, were examined. According to guidelines for clinical application, internal consistency scores were sufficient for OHIP-NL and OHIP-NL14, but insufficient for OHIP-NL5. Test-retest reliability (n = 64) was excellent for OHIP-NL and OHIP-NL14 and fair to good for OHIP-NL5. For all three versions, there was evidence for score validity: associations between OHIP summary scores on the one hand and validation variables and other RDC/TMD axis II variables on the other hand met the expectations and were statistically significant (P < 0·001). In conclusion, the OHIP-NL and OHIP-NL14 both performed comparatively well and better than the OHIP-NL5. When the length of the questionnaire (i.e. the time needed for its completion) is an issue, the OHIP-14 would therefore be the preferred version.

Dental students’ part‐time jobs in dental practices in the Netherlands

In the Netherlands, the Individual Health Care Professions Act (IHCP Act) allows dental students, amongst other non-qualified individuals, to work under certain conditions in a dental practice. The aim of the study was to determine how many dental students have part-time employment in dental practice and which professional tasks they carry out. We also asked the dental students their opinion about the IHCP Act. All the enrolled dental students at the Academic Centre for Dentistry Amsterdam (ACTA) in the Netherlands received a questionnaire by e-mail. Within 1 month, two reminders were sent. The response was 44% (427 students). Of the responding students, 71% had paid employment in addition to their study. Twenty-five per cent of all students worked in a dental practice, usually 8 h a week. Study year and age were positively related to working part-time in dental practice. Activities frequently performed were providing chair side assistance, giving oral hygiene instruction, fluoride applications, scaling and root planning. The self-reported knowledge about the IHCP Act was positively related to study year and working in a dental practice. Hardly any information about the requirements of the IHCP Act with regard to delegation of tasks was provided by the employer. Many Dutch dental students work in a dental practice, taking over a variety of tasks. Although the self-reported knowledge about the IHCP Act was relatively high, many dental students expressed the need for more detailed information about the legal aspects of their tasks.

Patients’ and parents’ expectations of orthodontic treatment

To investigate the expectations of children and their primary care-givers towards orthodontic treatment and to compare the results with those of a UK sample. A questionnaire survey of children and their primary care-givers attending for their first consultation. The Department of Orthodontics at the Academic Centre for Dentistry Amsterdam (ACTA), the Netherlands. A total of 168 subjects (84 patients and 84 parents) completed the questionnaire. The children were aged 10 to 14 years. The responses of the children and parents and differences between boys and girls were examined using parametric statistical methods. The data from the Dutch sample were compared with a similar UK sample. Patients and parents shared similar expectations of orthodontic treatment, with the exception of expectations of having a brace fitted at the first appointment, orthodontic treatment involving headgear, any problems with orthodontic treatment, duration of orthodontic treatment and concerning reactions from the public. Among the child participants, boys and girls only differed in their expectations of orthodontic treatment involving jaw surgery. Differences between Dutch and English participants were found regarding the first visit, type of orthodontic treatment, reactions from the public, and pain and problems with orthodontic treatment. Since the expectations of patients and their parents differ on several aspects, effective communication between the orthodontist, patient and parent is considered to be essential. Our hypothesis that Dutch patients' and parents' expectations of orthodontic treatment differ from the expectations of English patients and parents was supported.

Outcome of career expectancies and early professional burnout among newly qualified dentists

To measure burnout development, outcome of expectations with regard to dental career and feelings of being unprepared for practice among newly graduated general dental practitioners. In 1997, 50 dentists were approached to fill in the Maslach Burnout Inventory, Dutch version (UBOS) and some additional variables between six months and one year after graduation at the Academic Centre for Dentistry Amsterdam (ACTA) (76% response). Six years later, in 2003, the same 50 dentists, plus another 60 who had graduated in the same period at ACTA, were approached (78% response). Using Repeated Measures analysis, mean scores of dentists for whom two measurements were available on the three UBOS subscales (N=24) showed no statistically significant changes over six years on Emotional Exhaustion, Depersonalisation, or Personal Accomplishment. The same was true for group means of all in 1997 (N=33) compared with all in 2003 (N=82). However, according to manual criteria, varying percentages (7.2% - 24.4%) of dentists showed an unfavourable level on either one of the UBOS dimensions. Factors most frequently mentioned to be responsible for being unprepared for practice were: law and insurance matters (61.2%), practice organisation (56.6%) and staff management (55.2%). Most frequently reported factors that came out (much) worse than expected were: stressfulness of work (45.1%), and staff management (43.4%). Burnout appears no threat for the average newly qualified dentist. However, some individuals report alarmingly high burnout scores at an early professional stage. Practice management is the professional aspect about which young professionals worry most. It is recommended that dental schools pay attention to practice management skills and the stressfulness of work in the curriculum. Also, longitudinal monitoring of dental students and newly qualified dentists on burnout development is strongly advocated.

Development and implementation of new educational concepts in a dental curriculum

The Academic Centre for Dentistry Amsterdam introduced a fully renewed 5-year dental curriculum in September 2003. In this article, the educational principles and didactic choices that form the basis of the curriculum development are presented and attention is given to the process of development and the implementation strategy that constitute such an important part of the success of introducing a new curriculum. Special characteristics of the new curriculum are the clinical training practice, professional conduct, the elective profiles and academic education. In clinical practice, groups of students from different levels run a group practice in which they learn to work together, delegate tasks, solve clinical problems and apply evidence-based dentistry. In the new curriculum students learn to conduct themselves as professionals. In the third and in the fifth year, students choose an elective profile oriented, respectively, on research and on clinical knowledge and skills. Academic education is an important spearhead in this curriculum in which students not only learn why research is important to dentistry but also how dentists can use research to their own benefit. In development and implementation, a stepwise approach was used in which as many people as logistically possible were involved.

A functional perspective on oral implants – state‐of‐the‐science and future recommendations*

state-of-the-science and future recommendations* J. FEINE, R. JACOBS, F. LOBBEZOO, B. J . SESSLE, D. VAN STEENBERGHE**, M. TRULSSON, O. FEJERSKOV** & P. SVENSSON Faculty of Dentistry, McGill University, Montreal, Quebec, Canada, Laboratory of Oral Physiology, Department of Periodontology, Faculty of Medicine, Catholic University of Leuven, Leuven, Belgium, Department of Oral Function, Academic Centre for Dentistry Amsterdam (ACTA), Amsterdam, The Netherlands, Faculty of Dentistry, University of Toronto, Ontario, Canada, **Institute of Odontology, Karolinska Institute, Huddinge, Sweden, School of Dentistry, University of Aarhus, Aarhus, Denmark

Oral kinesiology. A new postgraduate programme in the Netherlands.

As one of the dental differentiations in The Netherlands, temporomandibular disorders (TMD) focuses on the diagnosis and treatment of pain and dysfunction of the masticatory system. Bruxism (i.e. tooth clenching and/or grinding) is thought to play an important aetiological role in TMD. Among others, bruxism may result in TMD pain and dental attrition. The close relationship between TMD, bruxism, and attrition necessitates an integrated approach to these clinical problems. This could be achieved through the multidisciplinary differentiation 'oral kinesiology', that covers not only the diagnosis and treatment of TMD and bruxism but also the restoration of worn dentitions. This article focuses on the background of oral kinesiology, as well as on the rationale to develop a curriculum for the postgraduate training of dentist-kinesiologists in the Netherlands. Further, the oral kinesiology curriculum of the Academic Centre for Dentistry Amsterdam will be introduced. This curriculum will ensure that specialized professionals, who are able to approach the different aspects of oral kinesiology in an integrated manner, are available not only for general dental practice but also for centres for special dental care and university departments. This will lead to improved care for patients, whose management is until now dispersed between various dental specialists.

Work place characteristics, work stress and burnout among Dutch dentists.

Work stress among dentists has been described several times, indicating a diversity of causes of stress. Professional burnout among dentists has been the subject of empirical study only occasionally. The aim of the present study was to investigate which occupational factors are related to levels of burnout among Dutch dentists. A distinction was made between actual work place characteristics and experienced pressure from specific aspects of dental work. With a response rate of 75%, a representative group of 709 Dutch general dental practitioners responded to a questionnaire containing a Dutch version of the Maslach Burnout Inventory (MBI-NL), the Dentists' Experienced Work Stress Scale (DEWSS), and a collection of items on work place conditions. No actual work place condition could be demonstrated to be correlated with high burnout levels. Lack of career perspective appeared to be the stress factor most strongly related to burnout. Mean burnout levels of all dentists were found to be favourable in comparison with Dutch norm scores: dentists showed less Emotional Exhaustion, less Depersonalization, and more Personal Accomplishment. It is concluded that the relation between lack of career perspective and burnout should stimulate serious attention for career planning among dentists.