Exploring opportunities for collaboration between the corporate sector and the dental education community.

The ultimate purpose of both dental industry and dental education is to improve the oral health of the public. This report provides background information on the different roles and objectives of the dental industry and dental education communities, the different operating environment of each sector and also areas of common interest where collaboration will be of mutual benefit. The report addresses five areas for potential collaboration between the dental industry and the dental education communities: 1. Contribution to joint activities. 2. Effectiveness and efficiency. 3. Workforce needs. 4. Middle- and low-income countries. 5. The future of International Federation of Dental Educators and Associations (IFDEA). The traditional areas of support and their limitations that have been provided by industry are outlined in the report and some new approaches for collaboration are considered. Industry-based research has been an important factor in developing new products and technologies and in promoting oral health. However there is a need to facilitate the introduction of these developments at an early stage in the education process. Industry has to operate in an efficient manner to remain competitive and maximise its returns and therefore survive. The academic sector operates in a different environment and under different governance structures; although some trends are noted towards adoption of greater efficiency and financial accountability similar to industry. Opportunities to jointly develop best business practices should be explored. Industry has responded well to the oral health needs of the public through the development of new products and technologies. The education community needs to respond in a similar way by examining different healthcare delivery models worldwide and developing programmes to train members of the dental team to cater for future needs and demands of communities in different regions of the world. The reputation of industry-based scientists and clinicians is high, and their role in contributing to the dental education process in practical ways needs to be explored and further developed. Closer relationships between industry scientists and faculty and students could assist industrys need and desire to develop new technologies for the broader dental care system. The corporate sector can play a key role in the future success of IFDEA by providing support and expertise in developing areas such as regional leadership institutes, a Global Faculty and Network and in collaborating in developing continuing education programmes as well as involvement in its governance. Thirteen recommendations are made in the report. These are considered to be important initial steps in developing the already strong relationship between the education and corporate sectors. Partnership and collaborating more effectively along the lines suggested should, almost certainly, generate mutually beneficial outcomes, whilst serving over the long term to elevate the publics oral health status on a global basis.

Maintaining dental education and specialist dental care during an outbreak of a new coronavirus infection. Part 1: a deadly viral epidemic begins.

During the three months from March 2003 the economically vibrant city of Hong Kong was seriously dislocated after becoming 'second port of call' of the new and potentially fatal disease, Severe Acute Respiratory Syndrome (SARS). The uncertainties during that period had a significant impact on the provision of dental care. However the city's only dental hospital continued to function and to support the Faculty of Dentistry of the University of Hong Kong in educating dental students and other members of the dental team. At the time of writing no transmissions of the disease have been attributed to procedures associated with dental healthcare. This article chronicles the sequence of events during the outbreak from a dental perspective. It highlights information that may be useful to dental colleagues who might someday be confronted with similar outbreaks of newly emerged potentially lethal infections.

A double-blind placebo-controlled trial of azithromycin as an adjunct to non-surgical treatment of periodontitis in adults: clinical results.

BACKGROUND/AIMS: The aim of the study was to investigate the clinical and microbiological effects of azithromycin as an adjunct to the non-surgical treatment of periodontitis in adults. Azithromycin is an antibiotic which is taken up by phagocytes and is released over long periods in inflamed tissue but requires a total of only three doses of 500 mg to produce its therapeutic effect. METHOD: 46 patients were treated in a double-blind placebo-controlled study with assessments at weeks 0, 1, 2, 3, 6, 10 and 22. Throughout the trial measurements were made of plaque, gingival bleeding, calculus, probing pocket depths and bleeding on probing. Microbiological sampling was carried out from a selected pocket >or=6 mm at each visit. The regime employed consisted of OHI, scaling and root planing at weeks 0, 1 and 2 with reinforcement of OHI and minimal scaling at weeks 6, 10 and 22. Patients were randomly assigned to receive either azithromycin, (A), or placebo capsules, (C), 500 mg, 1x daily for 3 days at week 2. 44 patients completed the study. Mean pocket depths were analysed using analysis of covariance in 3 groups with initial pocket depth values of 1-3 mm, 4-5 mm and >or=6 mm. RESULTS: The results of the microbiology have been reported in a separate paper. The clinical data showed that by week 22 a lower % of pockets initially >5 mm deep remained above that level in the 23 patients taking azithromycin (A), than the 21 taking the placebo (C), (A, 5.6%; C, 23.3%). Also at week 22, for pockets initially 4 mm or more, the test group had fewer pockets >3 mm deep (A, 26.1%; C, 44.3%), fewer failing to improve in probing depth (A, 6.6%; C, 21.6%) and fewer continuing to bleed on probing (A, 46.9%; C, 55.6%) when compared with the control group. Pocket depths initially 4-5 mm or 6-9 mm analysed by analysis of covariance showed lower mean pocket depths in the patients on azithromycin, at weeks 6, 10 and 22, (pockets initially 4-5 mm, p<0.001 on all occasions, pockets initially 6-9 mm, p<0.001, week 6; p< 0.003, week 10; p<0.001, week 22). CONCLUSIONS: Azithromycin may be a useful adjunct in the treatment of adult periodontitis, particularly where deep pockets are present.

Retention, antimicrobial activity, and clinical outcomes following use of a bioerodible tetracycline gel in moderate-to-deep periodontal pockets.

This randomized, examiner masked, split mouth study evaluated a new model to test periodontal therapy involving a novel bioerodible copolymer gel containing tetracycline hydrochloride. Responses to the tetracycline gel and untreated control were compared for product tolerance and 3 different measures of effectiveness (drug retention, changes in microbial levels, and clinical status). The test gel was administered by syringe into the periodontal pockets of 18 systemically healthy adult volunteers, each of whom presented with 3 or more sites with 6 mm probing depths. Gingival crevicular fluid samples were used to monitor daily drug levels over 7 days, while clinical responses were assessed at day 30. Overall, the test gel was well-tolerated by all patients. For the 3 effectiveness measures, tetracycline was released throughout the observation period and mean levels exceeded 100 microg/mL over 6 days, statistically significant reductions in selected periodontal pathogens were evident at day 7 but not at day 30, and mean probing depth reductions at test sites were 1.12 mm at 30 days versus 0.36 mm at untreated control sites (P=0.012). The safety profile, longer-term drug retention, antimicrobial activity, and clinical response in this Phase I study suggest that this tetracycline-containing copolymer gel platform may represent a safe and effective bioerodible therapy for periodontitis. The experimental model also shows merit for early phase clinical testing of novel therapeutic agents.

Characterisation of bioadhesives for periodontal and oral mucosal drug delivery.

Whilst there is keen interest in developing improved drug delivery devices to the periodontal pocket and oral mucosa, there are few reports which have examined the physical properties of gels and semi-solid formulations which favour retention and bioadhesion in situ. Hydration and rheological properties appear to be of prime importance in this context and this study aimed to correlate the measurement of these properties with observed bioadhesion, both in vitro and in vivo. Three candidate bioadhesives were selected from previous experiments which had used in vitro organ culture models. These were chitosan, xanthan gum and poly (ethylene oxide) aqueous formulations. Hydration rates with various media were determined in specially constructed cells. Rheological properties were measured using a controlled stress rheometer under carefully regulated conditions. These findings were also correlated with in vivo assessments in the periodontal pocket and oral mucosa. The results demonstrated that three formulations with differing bioadhesive properties also possessed widely different physical characteristics. Hydration experiments indicated a direct relationship between the rate of hydration and bioadhesion or retention. Rheological studies suggested that possession of a gel structure could be an important determinant of retention where shear displacing forces are present in vivo, e.g. the oral mucosa. Furthermore, these studies indicated that formulations which could demonstrate resistance to changes in rheological properties on hydration would also favour retention in situ. Physical characterisation therefore appears to have an important place in screening polymeric formulations prior to clinical testing in the periodontal pocket and oral mucosa.

An investigation of bioadhesion for periodontal and oral mucosal drug delivery.

Gel delivery vehicles have ideal placement characteristics for periodontal and oral mucosal drug delivery. However, the retention of the vehicle at the site may be of short duration thereby limiting its therapeutic effect. Bioadhesion has received little attention as a means of enhancing vehicle retention in the periodontal pocket and this study aimed to investigate the possible role of this phenomenon to aid oral drug delivery. Chitosan, xanthan gum and poly (ethylene oxide) were selected as potential vehicles from previous in vitro studies, since all 3 had shown good bioadhesive properties. Retention in the periodontal pocket was assessed by means of an insoluble fluorescein marker in 8 patients, and to the oral mucosa by the retention of a small plastic film in 12 subjects. The results showed that fluorescein release from the periodontal pocket was significantly longer for chitosan than for other gels or a water control. In contrast, xanthan gum gave the most prolonged adhesion time on the oral mucosa (153.5 min) followed by poly (ethylene oxide) (89.3 min) and chitosan (42.6 min), and these times were all significantly different from each other (p < 0.05). The results from this study would tend to suggest that the bioadhesive properties of an aqueous gel may be directly related to its retention both in the periodontal pocket and on the oral mucosa. However, other important factors for mucosal adhesion include the patient acceptability of the formulation and the choice of application site.

Azithromycin in the treatment of periodontal disease. Effect on microbial flora.

Azithromycin is an azalide antibiotic with excellent in vitro activity against a wide variety of oral bacteria. It has a long half-life, good tissue penetration and is preferentially taken up by phagocytes. We investigated the microbiological efficacy of azithromycin as an adjunct to the non-surgical treatment of adult chronic periodontitis; its clinical efficacy is dealt with in a separate paper. 46 patients were treated in a double-blind placebo controlled trial. Microbiological assessment of the same periodontal pocket (initially > 6 mm) was made at weeks 0, 2, 3, 6, 10 and 22. Either azithromycin 500 mg 1 x daily for 3 days or placebo was given at week 2. Particular attention was paid to the numbers of black pigmented anaerobes and spirochaetes present since these are the most commonly implicated pathogens in periodontal disease. Pigmented anaerobes were significantly reduced at weeks 3 and 6 in patients who received azithromycin compared to placebo and remained lower, although not significantly so, throughout the study. Counts of spirochaetes were significantly reduced throughout the study in patients who received azithromycin compared to placebo. Our microbiological study suggests that azithromycin may be useful as an adjunct in the treatment of periodontal disease.

In vitro assessment of bioadhesion for periodontal and buccal drug delivery.

Bioadhesion could significantly improve oral therapeutics for periodontal diseases and mucosal lesions. This project was designed to examine the factors important to prolonged adhesion (adhesion time) in organ culture under standardized conditions. A wide variety of bioadhesives were tested in the model and the effect of mucin was also examined. Whilst many gels adhered for 1-5 h, others (chitosan and Eudispert) showed no retention loss over 4 d. Histologically, chitosan also showed excellent tissue wetting properties. For most materials, however, mucin significantly reduced adhesion times (P < 0.05). In conclusion, the absence of mucin, the control of gel hydration and swelling, and wetting characteristics were identified as key factors for prolonged adhesion.

Cultural technique for in vitro modelling of prolonged bioadhesion.

This paper describes the development of a culture system for bioadhesion testing of gels over prolonged periods. Hamster cheek pouch mucosa was placed on collagen gels or steel mesh supports and submerged in growth medium for periods up to 7 d. Mucosal integrity and morphology were well maintained on mesh supports, but necrosis quickly occurred on collagen gels. Pilot studies with Orabase adhering to the tissue showed no detrimental effects, with the adhesive remaining in place for 4-6 h. It is concluded that the system shows promise for the investigation of prolonged bioadhesion.

Periodontology in general dental practice.

Periodontal care in general dental practice has begun to develop in a pattern which distinguishes it from more specialised periodontal therapy delivered in practices and hospital units devoted to that activity. Thus, more emphasis is laid upon screening in general practice, with monitoring of treatment progress in patients with mild disease also requiring a novel approach. The system needs to be underpinned with carefully designed record-keeping arrangements. There now appears to be an urgent need for a simple but robust method of measuring the outcome of simple periodontal treatment in general dental practice if further progress is to be made in this important area.

Attachment and orientation of human periodontal ligament fibroblasts to lipopolysaccharide-coated and pathologically altered cementum in vitro.

Previous studies have suggested that bacterial lipopolysaccharides (LPS) may inhibit fibroblast attachment to root surfaces affected by periodontal disease. This study was carried out to investigate the effects of pathologically altered cementum and cementum coated with LPS on the attachment and orientation of periodontal ligament fibroblasts in vitro. LPS caused a maximum reduction of cell orientation of 26% after 5 days' culture compared with controls. However cells did not become attached and orientated to pathologically altered root surfaces. It was concluded that as yet unidentified factors other than LPS may have greater significance when considering optimal methods for the preparation of root surfaces for new attachment procedures.

The distribution and quantitation of cementum-bound lipopolysaccharide on periodontally diseased root surfaces of human teeth.

The aim of this study was to estimate the concentration of cementum-bound LPS on a group of 12 teeth that had been extracted because of periodontitis. LPS on scaled root surfaces was labelled by immunogold/silver staining. The concentrations of LPS were estimated by quantifying the amount of bound silver label, using X-ray microanalysis in areas free of plaque or calculus. These were compared against standards of known LPS concentration, which were separately prepared for each sample. Cementum-bound LPS was detected at concentrations of up to 2 EU/mm2 of affected root surface. However, most of the root surfaces had considerably lower concentrations than this, the mean of all samples never exceeding 0.7 EU/mm2. LPS concentrations were highest on cementum towards the apical regions of the affected pocket. These findings confirm that cementum-bound LPS is only present in low concentrations on affected teeth, and suggest that the clinical significance of cementum-associated LPS may have been over-estimated in the past. The demonstration of LPS appears to be more important as an indicator of retained bacteria and calculus than of cementum-bound LPS per se.

Clinical evaluation of plaque removal with a double-headed toothbrush.

A blind, two-way, crossover clinical trial, completed by 44 adult subjects, instructed in specific oral hygiene techniques, was carried out to compare the effectiveness of plaque removal between a new Scandinavian double-headed toothbrush and a popular single-headed brush, each used for one week. The results showed that the double-headed brush was significantly more effective in removing plaque overall than a conventional brush. The effect was most evident on all lingual surfaces, especially in the lower arch and molar regions. It was also particularly pronounced when the double-headed toothbrush was allocated for use in the 2nd week of the study. There was no significant difference in the cleaning ability of the 2 brushes on the buccal surfaces of the teeth.

Periodontal awareness project in the United Kingdom: CPITN and self-assessment.

The outcome of a practitioner-orientated joint project between Unilever's Elida Gibbs and FDI, together with Elida Gibbs patient-orientated programme is described. The practitioner-orientated project concentrated on activities associated with the use of the Community Periodontal Index of Treatment Needs (CPITN) in general dental practice. These activities, involving sponsored research at a dental school and a study with UK dentists, have shown the potential of CPITN as a screening method for patients in general practice for periodontal diseases. There is evidence to show that patient-orientated programmes have increased periodontal awareness in the UK.