Periodontal conditions in Swiss army recruits: a comparative study between the years 1985, 1996 and 2006

AIM: To compare the periodontal conditions of Swiss Army recruits in 2006 with those of previous surveys in 1996 and 1985. MATERIAL AND METHODS: A total of six hundred and twenty-six Swiss Army recruits were examined for their periodontal conditions, caries prevalence, stomatological and functional aspects of the masticatory system and halitosis. In particular, this report deals with demographic data, the assessment of plaque index (PlI), gingival index (GI) and pocket probing depth (PPD). RESULTS: Two per cent of all teeth were missing, resulting in a mean of 27.44 teeth per subject, and 77% of the missing teeth were the result of pre-molar extractions due to orthodontic indications. The mean PlI and GI were 1.33 and 1.23, respectively. On average, 27% of the gingival units bled on probing. The mean PPD was 2.16 mm (SD 0.64). Only 3.8% of the recruits showed at least one site of PPD > or = 5 mm, and 1.4% yielded more than one site with PPD > or = 5 mm. In comparison with previous, this survey yielded lower bleeding on probing (BOP) percentages than in 1985, but slightly higher scores than in 1996. This may be attributed to increased PlI scores in 2006. However, PPD remained essentially unaltered from 1996 to 2006 after having improved significantly from 1985. CONCLUSION: A significant improvement of the periodontal conditions of young Swiss males was demonstrated to have taken place between 1985 and 1996, but no further changes during the last decade were noticed.     

An in vivo replica study of microbial colonization in "rapid" and "slow" dental plaque formers

The aim of the present study was to investigate the morphological features of supragingival plaque development in "rapid" and "slow" plaque formers using the replica technique. Forty-nine healthy volunteers were screened for their plaque formation rate after 3 days of oral hygiene abstinence using the plaque index (PI). Five subjects with the highest mean PI and six with the lowest mean PI were selected as "rapid" and "slow" plaque formers, respectively. After a series of thorough prophylaxis and oral hygiene instruction, all subjects went through a 14-day period of no oral hygiene to allow undisturbed plaque formation. Light body silicone elastomeric impressions were taken for the upper right central incisor of each subject on day-0, 1, 3, 7, and 14. Positive replicas were then poured from the impressions using epoxy resin and observed under a scanning electron microscope. A more complex supragingival plaque structure was seen in the day-1 and day-3 replicas of the "rapid" group compared to the "slow" group. From day-7 to day-14, during the maturation period of supragingival plaque, no discernible differences were noted between the two groups. Quantitatively, the percentage of plaque coverage on the tooth surfaces was higher in the "rapid" group than in the "slow" group in day-1 and day-3 replicas. These observations indicate that the morphological and topographical features of supragingival plaque in "slow" and "rapid" plaque formers differ, especially in the early developmental phase.     

A new experimental model for studies of local inflammatory reactions.

The aim of the present study was to develop and evaluate a method for studies of the early phase of the local inflammatory reaction, based on continuous diffusion of an inflammatory inducing agent. 25 rats were used. Four sterile teflon tablets were implanted subcutaneously in the back of each animal. After 3 weeks, when a connective tissue capsula had formed, the tablets were replaced by two test tablets, containing 35 micrograms lipopolysaccaride, one placebo and one teflon tablet. Five rats were sacrificed on day 0, 4, 7, 14, 21, respectively, and biopsies comprising tablet and surrounding tissue were harvested and exposed to routine histologic treatment. The number of leucocytes was assessed in four defined areas adjacent to each tablet. During the first seven days an increase in the number of leucocytes was seen in the tissues adjacent to test tablets. After 14 and 21 days the number of leucocytes was still high but lower as compared to day 7. In the tissues bordering the placebo and teflon tablets only few inflammatory cells were found. The results suggest that the tested method is suitable for studies of local inflammatory reactions during a 21 day period in experimental animals.     

The interactive examination: assessing students' self-assessment ability

BACKGROUND: The ability to self-assess one's competence is a crucial skill for all health professionals. The interactive examination is an assessment model aiming to evaluate not only students' clinical skills and competence, but also their ability to self-assess their proficiency. METHODS: The methodology utilised students' own self-assessment, an answer to a written essay question and a group discussion. Students' self-assessment was matched to the judgement of their instructors. As a final task, students compared their own essay to one written by an "expert". The differences pointed by students in their comparison documents and the accompanying arguments were analysed and categorised. Students received individual feedback on their performance and learning needs. The model was tested on 1 cohort of undergraduate dental students (year 2001, n = 52) in their third semester of studies, replacing an older form of examination in the discipline of clinical periodontology. RESULTS: Students' acceptance of the methodology was very positive. Students tended to overestimate their competence in relation to the judgement of their instructors in diagnostic skills, but not in skills relevant to treatment. No gender differences were observed, although females performed better than males in the examination. Three categories of differences were observed in the students' comparison documents. The accompanying arguments may reveal students' understanding and methods of prioritising. CONCLUSIONS: Students tended to overestimate their competence in diagnostic rather than treatment skills. The interactive examination appeared to be a convenient tool for providing deeper insight into students' ability to prioritise, self-assess and steer their own learning.     

The microbiota of periodontal pockets with different depths in therapy-resistant periodontitis

This study presents the composition of the cultivable microbiota colonising periodontal pockets of different depths among 2 patient-groups classified as non-responsive (NR-group; 11 participants) or responsive (R-group; 10 participants) to periodontal treatment. Microbiological samples from three types of pocket (< 4 mm deep A-samples; 4-5 mm B-samples; > 5 mm C-samples) were analysed by cultural methods for putative periodontitis pathogens, microbial groups constituting > or = 5% of the total cultivable flora and opportunistic pathogens. Actinomyces naeslundii, A. israelii, Bacteroides forsythus, Fusobacterium spp, Porphyromonas gingivalis, Prevotella intermedia, Peptostreptococcus micros, anaerobic streptococci and facultative anaerobic streptococci were most prevalent. Actinobacillus actinomycetemcomitans, Staphylococcus aureus, enteric rods and yeasts were less prevalent. The periodontitis pathogens Bacteroides forsythus, Fusobacterium spp, Porphyromonas gingivalis, Prevotella intermedia and Peptostreptococcus micros constituted together (on average) < or = 23% of the viable counts in the A- and B-samples of both patient groups and in the C-samples of the R-group. In the C-samples of the NR-group their mean counts were 45%. Correlations were found between smoking habits and the five pathogens in the C-samples and in pooled pocket depth samples. The results show that groups of periodontopathogens should be considered a causal factor in therapy-resistant periodontitis. Further, smoking and deep pockets can enhance a shift in the balance of the subgingival microflora predisposing a site to disease and a susceptible host may be the pre-requisite to therapy-resistant periodontitis.     

Assessing behavioural change support abilities of the oral healthcare team

Competent behavioural change intervention can be learned, practised and developed. Therefore, the teaching and assessment of this ability should be within the scope of both the undergraduate and post-graduate curriculum. Assessment should target knowledge base and skills in the areas of counselling, communication and behaviour. Assessment of the knowledge base should ideally be conducted in a comprehensive, multidisciplinary, centrally based manner in the pre-clinical curriculum. Assessment of skills in the areas of communication, counselling and behaviour change is a wider aim that should be integral throughout the curriculum. In continuing education (CE) environments, an initial 'screening' assessment would help educators to adjust the course to the participants' background and needs. Furthermore, three major assessment schemes are proposed: (1) assessment of knowledge and skills, (2) evaluation of the whole course by the participants, and (3) assessment of the implementation process, four to six months after completion.     

The role of the curriculum and other factors in determining the medium‐ to long‐term attitude of the practicing dentist towards life‐long learning

Objectives: To investigate the significance of the undergraduate dental curriculum on the medium‐ to long‐term attitudes of the clinician to life‐long learning, and to identify demographical and professional characteristics which may influence this attitude. Methods: A specially designed questionnaire targeted 12 cohorts of dentists who qualified from Dublin Dental School and Hospital between 1994 and 2005. The curricula of the cohorts varied from fully didactic, exclusively Problem Based Learning or a hybrid for the oldest, youngest and middle graduates, respectively. Participants were questioned about current professional activities, postgraduate training, practice type, hospital affiliation, use of information services and time dedicated to continuing dental education (CDE), etc. A number of dental scenarios were proposed to determine if participants were adherent to current clinical guidelines. Additionally, a visual analogue scale assessed the overall satisfaction of dentists with their undergraduate programme and determined their opinion regarding its influence on subsequent ability to practice dentistry and keep up‐to‐date with scientific developments. Results: Contingency analysis of the association between curriculum and continuous educational data did not produce statistical significance. Dentists who work in a hospital environment spend more time on CDE (χ², Pearson’s, P = 0.001), are more adherent to current guidelines (χ², Pearson’s, P = 0.005) and found their undergraduate studies more enjoyable (Wilkoxon/Kruskal–Wallis, P = 0.01). Conclusions: Undergraduate curriculum type was found to have very little or no effect on the graduate’s attitude towards life‐long learning or confidence in their ability to practice dentistry. However, these attitudes did appear to be influenced by certain family, demographical and professional characteristics.     

Supra-alveolar periodontal healing of auto- and allotransplanted teeth in monkeys

Although intra-alveolar healing of allotransplanted teeth often shows pathological changes due to rejection of the tooth graft, previous clinical findings seem to indicate that the supra-alveolar part of the allografts heals differently, which is of significant prognostic value. The aim of the present study was to determine the healing of the cervical part of the periodontium of auto- and allotransplanted mature teeth in monkeys. In 4 adult, immunologically unmatched, green vervet monkeys 16 mature permanent maxillary and mandibular incisors were extracted, endodontically treated and either auto- or allotransplanted; 8 untreated neighbouring incisors served as controls. Block biopsies including part of the tooth and the adjacent vestibular tissues were obtained after a healing period of 8 weeks. The biopsies were decalcified in EDTA and embedded in Epon. In semi-thin section (1.5 microns) the morphology of the supra-alveolar periodontal tissues was analysed in the light microscope. The orientation of the connective tissue fibres close to the root surface was found to be more parallel to the root surface of allotransplants compared with autografts, while in the control teeth the fibres were generally oriented perpendicular to the root surface. Resorption of the root was seldom found in the supra-alveolar portions of any of the transplanted teeth. The junctional epithelium had migrated slightly apically onto the root surfaces of allotransplanted teeth. The gingival connective tissue adjacent to allotransplanted teeth showed a significantly increased number of lymphocytes compared with autografts and controls.(ABSTRACT TRUNCATED AT 250 WORDS)     

Feasibility of and satisfaction with the use of low-bandwidth videoconferencing for examination of undergraduate students

We investigated the feasibility and students' acceptance of Internet-based videoconferencing as a communications method during examinations. Thirty-nine second-year dental students took an interactive examination in periodontology, comprising self-assessment, essay writing, discussion and feedback. The students were randomly divided into two groups, which were examined through the standard classroom procedure (n =15) or through Internet-based videoconferencing (n =24). Students evaluated the experience using a standardized questionnaire. The technology proved to be reliable. The interactive examination technique was well accepted, although there was significantly less satisfaction in the videoconference group (P <0.01). There were no significant differences in the performance of students between the two modalities. Interaction was stressed as one of the major strengths of the examination by students in the conventional group, but it appeared to be less appreciated by the videoconference group. Internet-based videoconferencing can successfully facilitate a highly structured assessment, although students seem to prefer classroom assessment.