PAR-2 regulates dental pulp inflammation associated with caries

Protease-activated receptors (PARs) are G-protein-coupled receptors that are activated enzymatically by proteolysis of an N-terminal domain. The cleavage and activation of PARs by serine proteases represent a novel mechanism by which such enzymes could influence the host inflammatory response. The aim of this study was to determine whether PAR-2 expression and activation were increased in dental caries. Using immunohistochemistry, we showed PAR-2 to be localized to pulp cells subjacent to caries lesions, but minimally expressed by healthy pulp tissue. Trypsin and the PAR-2 agonist (PAR2-AP) activated PAR-2 in an in vitro functional assay. Endogenous molecules present in pulp cell lysates from carious teeth specifically activated PAR-2, but those from healthy teeth failed to do so. The activation of PAR-2 in vitro was shown to increase the expression of the pro-inflammatory mediator cyclo-oxygenase-2 (COX-2), providing a mechanism whereby PAR-2 could modulate pulpal inflammation.

Neuropeptide Y Y1 receptor in human dental pulp cells of noncarious and carious teeth

AIM

To determine the distribution of the NPY Y1 receptor in carious and noncarious human dental pulp tissue using immunohistochemistry. A subsidiary aim was to confirm the presence of the NPY Y1 protein product in membrane fractions of dental pulp tissue from carious and noncarious teeth using western blotting.

METHODOLOGY

Twenty two dental pulp samples were collected from carious and noncarious extracted teeth. Ten samples were processed for immunohistochemistry using a specific antibody to the NPY Y1 receptor. Twelve samples were used to obtain membrane extracts which were electrophoresed, blotted onto nitrocellulose and probed with NPY Y1 receptor antibody. Kruskal-Wallis one-way analysis of variance was employed to test for overall statistical differences between NPY Y1 levels in noncarious, moderately carious and grossly carious teeth.

RESULTS

Neuropeptide Y Y1 receptor immunoreactivity was detected on the walls of blood vessels in pulp tissue from noncarious teeth. In carious teeth NPY Y1 immunoreactivity was observed on nerve fibres, blood vessels and inflammatory cells. Western blotting indicated the presence and confirmed the variability of NPY Y1 receptor protein expression in solubilised membrane preparations of human dental pulp tissue from carious and noncarious teeth.

CONCLUSIONS

Neuropeptide Y Y1 is expressed in human dental pulp tissue with evidence of increased expression in carious compared with noncarious teeth, suggesting a role for NPY Y1 in modulation of caries induced pulpal inflammation.

Detection of individual human neutrophil ?-defensins (human neutrophil peptides 1, 2 and 3) in unfractionated gingival crevicular fluid?A MALDI-MS approach

The role of antimicrobial peptides is particularly important in the oral cavity where there is constant challenge by microorganisms. The alpha-defensins are a group of cationic peptides that comprise 30-50% of the total protein in azurophilic granules of human neutrophils. They include the human neutrophil peptides (HNP) 1, 2 and 3 which have almost identical amino acid sequences but differ in their biological activities. The amino acid sequence similarities of the defensins have made it difficult to unequivocally determine the presence of individual defensins using antibody-based techniques. However, by virtue of their cationic nature we postulated that the defensins would fly particularly well in mass spectrometry and that this characteristic would allow facile identification of individual HNPs in unfractionated gingival crevicular fluid (GCF) from periodontitis patients and healthy controls. Although there was variability in levels of defensins detected in periodontal health and disease, HNP-1 was always identified as the major peak in the triad and HNP-3 as the minor peak, lending support to the hypothesis that HNP-2 may arise by post-translational proteoyltic cleavage of HNP-3 rather than HNP-1. The finding that the defensins were more abundant in a higher proportion of the healthy sites studied could be linked to a more intact defensin barrier in periodontal health.

Extraction and radioimmunoassay quantitation of neuropeptide Y (NPY) and vasoactive intestinal polypeptide (VIP) from human dental pulp tissue

The measurement of neuropeptides in complex biological tissue samples requires efficient and appropriate extraction methods so that immunoreactivity is retained for subsequent radioimmunoassay detection. Since neuropeptides differ in their molecular mass, charge and hydrophobicity, no single method will suffice for the optimal extraction of various neuropeptides. In this study, dental pulp tissue was obtained from 30 human non-carious teeth. Of the three different neuropeptide extraction methods employed, boiling in acetic acid in the presence of protease inhibitors yielded the highest levels of neuropeptide Y (NPY) and vasoactive intestinal polypeptide (VIP). High pressure liquid chromatography (HPLC) analysis of dental pulp tissue verified the authenticity of the neuropeptides extracted.

Quantitative analysis of substance P, neurokinin A and calcitonin gene-related peptide in pulp tissue from painful and healthy human teeth

AIM

The purpose of this study was to investigate the levels of substance P (SP), neurokinin A (NKA) and calcitonin gene-related peptide (CGRP) in painful and healthy human dental pulps.

METHODOLOGY

Forty-six samples of pulp tissue were collected from extracted or endodontically treated painful teeth and 20 from clinically healthy teeth extracted for orthodontic reasons. All pulp samples were boiled in 0.5 m acetic acid for 10 min, centrifuged and the supernatant collected. SP, NKA and CGRP levels were measured using radioimmunoassay.

RESULTS

Substance P and CGRP were present in all samples and NKA was detected in 96% of the pulps. CGRP was present in much higher concentrations than SP and NKA in both painful and non-painful teeth. The painful teeth had significantly higher concentrations of SP (P = 0.02), NKA (P < 0.001) and CGRP (P = 0.03) than non-painful teeth. The concentration of CGRP was significantly higher in the pulps of smokers compared with non-smokers (P = 0.02).

CONCLUSIONS

Elevated levels of these neuropeptides in pulps from painful teeth indicate that they may play an important role in the process of pulpal inflammation and pain. Further investigation of the association between these neuropeptides and pulpal status may help to improve our understanding of pulpal inflammation and dental pain.

Occlusal considerations in periodontics

Periodontal disease does not directly affect the occluding surfaces of teeth, consequently some may find a section on periodontics a surprising inclusion. Trauma from the occlusion, however, has been linked with periodontal disease for many years. Karolyi published his pioneering paper, in 1901 'Beobachtungen uber Pyorrhoea alveolaris' (occlusal stress and 'alveolar pyorrhoea'). (1) However, despite extensive research over many decades, the role of occlusion in the aetiology and pathogenesis of inflammatory periodontitis is still not completely understood.

Quantitative analysis of MRP-8 in gingival crevicular fluid in periodontal health and disease using microbore HPLC

BACKGROUND

The protein components of GCF can be separated by reverse-phase microbore HPLC on a C18 column with detection on the basis of 214 nm absorbance. A single major symmetrical protein peak eluting with a retention time of 26 min (50% acetonitrile) was evident in gingival crevicular fluid (GCF) from periodontitis patients but not in healthy GCF. This protein was identified as human MRP-8 by N-terminal amino acid sequencing and liquid chromatography quadropole mass spectrometry.

AIMS

To quantify the amount of MRP-8 detectable in GCF from individual healthy, gingivitis and periodontitis affected sites and to study the relationship, if any, between the levels of this responsive protein and periodontal health and disease.

METHODS

GCF was sampled (30 s) from healthy, gingivitis, and periodontitis sites in peridontitis subjects (n=15) and from controls (n=5) with clinically healthy gingiva and no periodontitis. Purified MRP-8 was sequenced by Edmann degradation and the phenylthiohydantoin (PTH) amino acid yield determined (by comparison of peak area with external PTH amino acid standards). This value was subsequently used to calculate the relative amount of protein in the peak eluting with a retention time of 26.0 min (MRP-8) in individual GCF chromatograms.

RESULTS

Higher levels of MRP-8 were detected in inflammatory sites: periodontitis 457.0 (281.0) ng; gingivitis 413.5 (394.5) ng compared with periodontally healthy sites in diseased subjects 14.6 (14.3) ng and in controls 18.6 (18.5) ng, p=0.003. There was at least 20-fold more MRP-8 in the inflammatory compared with the healthy sites studied.

CONCLUSIONS

The preliminary data indicate that MRP-8 is present in GCF, with significantly greater amounts present at diseased than healthy sites. A systematic study of the relationship of this protein to periodontal disease could prove useful in further clarifying whether MRP-8 could be a reliable GCF biomarker of gingivitis and periodontitis.

Pre-treatment conceptions of periodontal disease and treatment in periodontal referrals

BACKGROUND

Patients preconceptions of periodontal therapy have not been extensively studied and are poorly understood.

AIMS

To register specific anxieties and preconceptions held by patients referred for specialist periodontal treatment and to investigate the risks such patients were prepared to take of progressive periodontal problems before deciding that periodontal treatment was necessary.

MATERIALS AND METHODS

79 patients referred for specialist treatment completed a structured questionnaire. Participants completed visual analogue scales to quantify the risks which they were prepared to take of various symptoms of periodontal disease before they believed treatment was essential.

RESULTS

The majority (71%) had anxieties about pending treatment with the main concern being pain. Those who had sought information prior to treatment mainly did so from close relatives. The majority of patients opted to take no or a very low (<20%) risk of any periodontal problems and, therefore, were supportive of treatment. The loss of many teeth due to periodontal disease was the least acceptable outcome followed by tooth mobility. Patients were prepared to accept a significantly higher risk of bleeding on brushing (p<0.0001) than any of the other outcomes investigated. Females recorded substantially lower risk scores than males particularly in relation to developing recession or tooth mobility in the absence of treatment. Patients who were worried about experiencing pain during treatment recorded lower risk scores than those who had no anxiety regarding pain.

CONCLUSION

It is concluded that the Norwegian periodontal referrals studied were prepared to take very low risks of further periodontal symptoms despite high levels of anxiety and evidence of a lack of knowledge regarding periodontal treatment.

Resolution of gingival overgrowth following change from cyclosporin to tacrolimus therapy in a renal transplant patient

Gingival overgrowth is a well documented and common side-effect of cyclosporin therapy. Gingival swelling in this condition hinders efficient oral hygiene and is of aesthetic concern to patients. This case report outlines rapid and dramatic reduction in overgrowth when tacrolimus replaced cyclosporin as the immunosuppressive agent in a renal transplant patient with established overgrowth.

The influence of transforming growth factor-beta1 gene polymorphisms on the severity of gingival overgrowth associated with concomitant use of cyclosporin A and a calcium channel blocker

BACKGROUND

The purpose of this study was to determine whether the prevalence and severity of gingival overgrowth in renal transplant recipients concomitantly treated with cyclosporin and a calcium channel blocker was associated with functional polymorphisms within the signal sequence of the transforming growth factor-(TGF)beta1 gene.

METHODS

The extent and severity of gingival overgrowth for 164 renal transplant recipients immunosuppressed with cyclosporin A and concomitantly taking a calcium channel blocker since transplant were entered into the study (86 in Manchester, 78 in Belfast). Two biallelic polymorphisms of the TGF-beta1 gene were studied at position +869, codon 10 (leucine to proline substitution), and position +915, codon 25 (arginine to proline substitution).

RESULTS

Subjects who were homozygous for proline at codon 10 had significantly higher overgrowth scores than those who were heterozygous (P= 0.03) or homozygous for leucine (P= 0.01). Subjects who were heterozygous (arginine/proline) at codon 25 had a significantly higher (P= 0.04) gingival overgrowth score than those who were homozygous for arginine. Logistic regression analysis indicated that for codon 25 independent predictors of severe gingival overgrowth were the heterozygous arginine/proline genotype (P= 0.009) and whether the individual was young (P= 0.05).

CONCLUSIONS

Polymorphisms in the TGF-beta1 gene influence the expression of gingival overgrowth in renal transplant recipients concomitantly treated with cyclosporin and a calcium channel blocker. The polymorphism in the TGF-beta1 gene at codon 25 represented an independent genetic determinant of severe gingival overgrowth in the susceptible subjects studied.

Identification of MRP-8 (calgranulin A) as a major responsive protein in chronic periodontitis

The purpose of the study was to analyse how the protein composition of the inflammatory exudate associated with chronic periodontitis differed from the exudate in periodontal health. Gingival crevicular fluid (GCF) was collected from sites with chronic periodontal inflammation and from non-diseased sites in healthy control subjects. Microbore HPLC analysis revealed one major difference in GCF protein profiles between healthy controls and periodontitis patients. The protein enhanced in periodontitis patients was identified as migration inhibitory factor-related protein-8 (MRP-8) by a combination of N-terminal amino acid sequencing, mass spectrometry, and SDS-PAGE. Together, these data demonstrate, for the first time, the presence of monomeric MRP-8 in an inflammatory exudate. Whether monomeric MRP-8 is a unique feature of chronic periodontal inflammation is not yet clear, but the chemotactic properties of this peptide support a functional role for MRP-8 in periodontal inflammation.

Carboxypeptidase-mediated metabolism of calcitonin gene-related peptide in human gingival crevicular fluid--a rôle in periodontal inflammation?

BACKGROUND

Metabolism by peptidases plays an important rôle in modulating the levels of biologically-active neuropeptides. The metabolism of the anti-inflammatory neuropeptide calcitonin gene-related peptide (GCRP), but not the pro-inflammatory neuropeptides substance P (SP) and neurokinin A (NKA) by components of the gingival crevicular fluid (GCF), could potentiate the inflammatory process in periodontitis.

AIMS

To characterise the extracellular hydrolysis of CGRP as a mechanism for the selective inactivation of this neuropeptide in GCF from periodontitis sites.

METHODS

Samples of GCF from periodontitis patients and periodontally-healthy subjects were incubated with synthetic human SP, NKA or CGRP. Reaction between the GCF constituents and synthetic peptides was allowed to progress from 0-180 min. Results of neuropeptide metabolism at each time were analysed by matrix-assisted laser desorption/ionisation mass spectrometry.

RESULTS

There was no evidence of metabolism of SP, NKA or CGRP by constituents of healthy GCF. Metabolism of synthetic SP and NKA was minimal even after extensive incubation with periodontitis GCF. However, loss of carboxy-terminal amino acids was evident after only 1 min incubation with periodontitis GCF. The pattern of CGRP metabolism, which proceeded from the C-terminus, indicated that the neuropeptide was degraded by a carboxypeptidase. After 180 min, there was extensive carboxypeptidase degradation of CGRP to an 11 amino acid peptide.

CONCLUSIONS

It is concluded that carboxypeptidase activity in GCF from periodontitis patients is responsible for rapid breakdown of CGRP but not SP or NKA. The rapid action of this carboxypeptidase on the anti-inflammatory neuropeptide CGRP is suggestive of a pathophysiological rôle for the enzyme in selectively degrading CGRP, thereby potentiating periodontal inflammation.

Changes in substance P and neurokinin A in gingival crevicular fluid in response to periodontal treatment

BACKGROUND

The study of periodontitis provides a unique model for assessing the involvement of neuropeptides in inflammatory disease.

AIM

To investigate the effects of periodontal treatment, resulting in a return to periodontal health, on the levels of substance P (SP) and neurokinin A (NKA) in gingival crevicular fluid (GCF).

METHOD

We completed a cause of non-surgical treatment for 8 subjects with periodontitis (6 females 2 males, mean age 45.1, range 38-67 years) started a course of non-surgical periodontal treatment. Clinical indices were measured at 2 periodontitis sites at the initial visit and at 8 weeks after the completion of treatment in each subject. A 30-s sample of GCF was collected from each test site using perio paper strips. Each strip was placed into 500 microl of ice cold 0.1 M PBS, pH 7.4, vortex mixed for 30 s, and then stored at -70 degrees C until analysed by radioimmunoassay.

RESULTS

The clinical condition of all test sites improved as a result of the periodontal treatment. The levels (pg/30 s sample) of SP fell from 56.3 (SD 66.0) at the initial visit to 4.2 (3.1) after treatment, p=0.017. The concentration (pg/microl) of SP in GCF fell from 140.6 (175.6) to 24.2 (11.1), p=0.036. The levels of NKA fell from 30.5 (17.1) to 10.6 (4.9), p=0.012 whereas the concentration changed little from 85.4 (43.5) to 61.6 (15.1), p=0.41.

CONCLUSION

The reduction in inflammation resulting from effective periodontal treatment is associated with a reduction in the levels of tachykinins in gingival crevicular fluid.

Reduction in gingival overgrowth associated with conversion from cyclosporin A to tacrolimus

BACKGROUND

Unsightly gingival overgrowth affects many individuals immunosuppressed with cyclosporin A (CsA). Current management involves repeated periodontal surgery and intensive hygienist support. Tacrolimus is an effective alternative immunosuppressive agent for renal transplantation which does not appear to produce gingival enlargement.

AIMS

The purpose of the present study was to monitor the gingival response of 4 renal transplant patients (RTPs), with clinically significant CsA-induced gingival overgrowth, after their immunosuppressive therapy was switched to tacrolimus.

METHODS

Intra-oral photographs and alginate impressions were taken both prior to the drug conversion and again, 6 to 9 months later. Gingival overgrowth scores were determined, from plaster models on both these occasions.

RESULTS

All of the RTPs experienced significant resolution of their gingival enlargement within the time period studied; however, only one had complete regression.

CONCLUSION

It is concluded that conversion of RTPs with gingival overgrowth from CsA to tacrolimus may provide an effective management strategy for this clinical problem.

The calcium channel blocker used with cyclosporin has an effect on gingival overgrowth

BACKGROUND/AIMS

To investigate whether the choice of calcium channel blocker, used in conjunction with cyclosporin A, affected the prevalence of gingival overgrowth.

METHOD

A cohort of 135 renal transplant recipients who had been medicated with cyclosporin A in combination with either nifedipine (89) or amlodipine (46) since transplant, took part in the study. The inclusion criteria were that eligible subjects had been in receipt of a kidney transplant for at least 12 months, had at least 10 teeth and had not received specialist periodontal treatment. The age, gender, current drug regimen and dosage were recorded for each participant and alginate impressions taken of both arches. The presence and severity of gingival overgrowth were scored from plaster models.

RESULTS

A higher proportion (72%) of the amlodipine group were categorised as having gingival overgrowth compared with only 53% of the nifedipine group, chi square=4.5, p<0.05. Logistic regression analysis was used to explore the relationship between the presence or absence of gingival overgrowth (dependent variable) and age, gender, time since transplant, dose of cyclosporin A, centre in which the patient was treated, and the calcium channel blocker used (independent variables). Independent predictors of gingival overgrowth in this multivariate analysis were whether the individual was treated with amlodipine or nifedipine (p=0.01) and whether the individual was young or old (p=0.01). Within the multivariate analysis, the odds ratio for amlodipine to be associated with gingival overgrowth compared with nifedipine was 3.0 (confidence interval 1.3-6.9).

CONCLUSIONS

The prevalence of gingival overgrowth in renal transplant recipients maintained on cyclosporin A and nifedipine is lower than those treated with cyclosporin A and amlodipine.

A comparison of four extraction methods for substance P, neurokinin A and calcitonin gene-related peptide from human dental pulp tissue

Measuring neuropeptides in biological tissues by radioimmunoassay requires efficient extraction that maintains their immunoreactivity. Many different methods for extraction have been described, but there is little information on optimal extraction methods for individual neuropeptides from human dental pulp tissue. The aim was therefore to identify an effective extraction procedure for three pulpal neuropeptides; substance P, neurokinin A and calcitonin gene-related peptide. Tissue was obtained from 20 pulps taken from teeth freshly extracted for orthodontic reasons. The pulp samples were divided into four equal groups and different extraction methods were used for each group. Boiling whole pulp in acetic acid gave the highest overall yield and, in addition, offered an easy and rapid means of pulp tissue processing. The use of protease inhibitors did not increase the recovery of the immunoreactive neuropeptides but did provide the best combination of maximal recoveries and minimal variability. These results should be useful for planning the extraction of these neuropeptides from human pulp tissue in future studies.

Variation in periodontal referral in 2 regions in the UK

This study investigated the periodontal referral patterns of general dental practitioners (GDPs) in Northern Ireland (NI) and North West England (NWE). A questionnaire dealing with periodontal referral was sent to all 520 GDPs registered in NI and to 274 GDPs in NWE. A usable return was made by 355 (68%) in NI and 189 (70%) in NWE. The NI dentists made significantly more periodontal referrals (median 5, range 0-80) in the year preceding the survey than those in NWE (median 2, range 0-50), p<0.001. Distance was the only factor significantly related to the referral rate in both regions with those who practised more than 25 miles from a specialist referring significantly fewer patients in both regions. In NI, there was a trend towards increased periodontal referral by GDPs who had attended more postgraduate courses; however, in NWE, this was not the case. The GDPs in NWE were significantly less likely than those in NI to refer patients with medical conditions. It is concluded that there is considerable variation in periodontal referral both within and between the 2 regions studied. It is further concluded that in many cases, non-disease factors, such as the accessibility of the specialist service, have powerful effects on the decisions made by dentists and patients in these regions (NI and NWE) in relation to periodontal referral. Much of the variance in referral in North West England, as in Northern Ireland, remains unexplained.

Periodontal response to cantilevered and fixed-fixed resin bonded bridges

The periodontal response to two types of resin bonded bridges was investigated. Cantilever or fixed-fixed resin bonded bridges which had been in service for at least two years were reviewed. Periodontal indices (plaque index, gingival index, bleeding index and pocket depth) were recorded for each bridge abutment and for matched contralateral teeth. There was no difference in the periodontal condition of the abutment teeth between cantilever and fixed-fixed resin bonded bridges, after they had been in service for at least two years. There was evidence of greater plaque accumulation and higher gingivitis levels affecting abutment teeth for both types of bridges compared with control teeth.

Signal recognition particle receptor (SRPR) is downregulated in a rat model of cyclosporin A-induced gingival overgrowth

Differential display is a powerful technique which can be used to identify those genes whose expression is altered between two or more tissues under investigation. We have applied differential display to a rat model of cyclosporin A-induced gingival overgrowth (CIGO) to identify genes which are differentially expressed as a result of drug treatment. Ten weanling Wistar rats were fed with a pelleted diet containing cyclosporin A (CsA) at 120 mg/kg for 10 d and then 200 mg/kg for a further 30 d prior to culling. Experimental rats were compared with 10 age/sex-matched rats on a control diet. Significant evidence of overgrowth was observed in the interdental papilla between the mandibular first and second molar teeth in the CsA group. Differential display was performed on total cellular RNA extracted from the mandibular buccal gingiva. A cDNA product was isolated which was underexpressed in the overgrowth tissue and demonstrated a 95% sequence homology to the human signal recognition particle receptor (Human Docking Protein). Preliminary studies indicate that this gene is also underexpressed in human CIGO tissue. The method of approach and the potential implications of our findings are discussed.

Smoking and patterns of bone loss in early-onset periodontitis

BACKGROUND

The aims of this study were to investigate the extent and distribution of bone loss in subjects with early-onset periodontitis (EOP) referred for periodontal care and to study the relationship between smoking and EOP.

METHODS

A total of 71 consecutive referrals (21 male, 50 female) under 35 years old, who were otherwise healthy, with a clinical diagnosis of severe periodontitis were recruited for the study. Bone loss was measured from available radiographs using a Schei ruler to identify 2 patterns of destruction: localized (LEOP) in 41 (58%) and generalized early-onset periodontitis (GEOP) in 30 (42%) subjects.

RESULTS

The study population had a mean of 25.0 (SD 2.4) teeth, excluding third molars, and mean bone loss of 28.7% (SD 13.0). Bone loss was more severe in the maxilla, 30.9% (SD 13.8) compared with 26.6% (SD 14.0) in the lower arch. More than one-third (36%) of the teeth examined had at least 30% bone loss. Mean smoking experience was 9.2 pack years (SD 5.6), and 39 (55%) of the EOP subjects smoked. Smokers had significantly more maxillary bone loss than non-smokers. A much higher proportion of GEOP (70%) currently smoked compared with 44% of LEOP, P = 0.029.

CONCLUSIONS

It is concluded that young adults with early-onset forms of periodontitis often have advanced periodontal destruction before they are referred for specialist care. In addition, there was a relationship between smoking and severe bone destruction in subjects with EOP, particularly those with generalized disease.

Calcitonin gene-related peptide in gingival crevicular fluid in periodontal health and disease

The aims of the present study were to investigate whether calcitonin gene-related peptide (CGRP) was present in gingival crevicular fluid in both periodontal health and disease and to study the relationship with periodontal inflammation. Gingival crevicular fluid (GCF) was collected from a healthy, a gingivitis and a periodontitis site in 18 subjects with periodontitis and from a healthy site in 19 subjects without periodontitis. The volume of GCF was measured and each sample subsequently analysed for CGRP by radioimmunoassay. In subjects with periodontitis, CGRP immunoreactivity (CGRP-IR) was not detected in any periodontitis sites, nor in 67% of gingivitis and 28% of periodontally-healthy sites. The total amount of CGRP-IR was significantly elevated in periodontally healthy (p=0.0015) and gingivitis (p=0.027) compared with periodontitis sites. CGRP-IR was present in 89% of the healthy sites sampled in control subjects at comparable levels to those in healthy sites in periodontitis subjects. It is concluded that in periodontal inflammation, particularly in deep pockets, constituents of GCF process and degrade CGRP.

Cyclosporin A regulates interleukin-1beta and interleukin-6 expression in gingiva: implications for gingival overgrowth

BACKGROUND

Gingival overgrowth is a common side effect following the administration of cyclosporin A (CsA); however, the cellular mechanisms remain poorly understood. CsA's immunosuppressant properties involve the regulation of synthesis and cellular response to cytokines. A CsA-induced alteration in the cytokine profile within gingival tissue could provide a mechanism for gingival hyperplasia. The aim of this study was to investigate the effects of CsA on the production of 2 cytokines - interleukin-1beta (IL-1beta) and interleukin-6 (IL-6) - by both gingival fibroblasts and peripheral blood mononuclear cells (PBMC).

METHODS

Cells were stimulated for 24 hours in the presence of CsA over a concentration range of 100 to 2,000 ng/ml and the resultant cytokine production determined by ELISA. In addition, levels of both cytokines within normal, inflamed, and overgrown gingival tissue were determined.

RESULTS

CsA inhibited IL-6 production by gingival fibroblasts in a dose-dependent manner. In contrast, at a concentration of 2,000 ng/ml, CsA stimulated IL-6 production by PBMC (P <0.05). Fibroblasts derived from overgrown gingiva produced significantly higher levels of IL-6 than their normal counterparts (P <0.05). CsA inhibited IL-1beta production by PBMC over the whole concentration range (P <0.05). IL-1beta was not found in measurable quantities in any of the fibroblast cultures. Levels of IL-6 extracted from overgrown gingival tissue were significantly higher than in inflamed or normal tissue. In contrast IL-1beta levels in overgrown tissue were not statistically significantly greater than those in inflamed tissue.

CONCLUSIONS

These results show that CsA does regulate cytokine expression in gingival tissue. This effect may play an important role in the pathogenesis of CsA-induced gingival overgrowth.

Cyclosporin associated gingival overgrowth in renal transplant recipients

OBJECTIVES

To investigate the prevalence and severity of gingival overgrowth in a group of renal transplant recipients treated in one centre in Northern Ireland.

STUDY DESIGN

A consecutive group of patients who had had a renal transplant for at least 6 months and were attending the Renal Unit in Belfast City Hospital took part in the study. These were divided into a group of 84 subjects treated with cyclosporin since their transplant who were compared with a control group of 36 transplant recipients who had never received cyclosporin. Each subject had a periodontal examination and completed a questionnaire. The severity of gingival overgrowth was scored from plaster models.

OUTCOME MEASURES

Clinically significant gingival overgrowth was equated with a score of > or = 30 using the index developed by Seymour et al (1985).

RESULTS

41 (49%) of the cyclosporin group had clinically significant gingival overgrowth compared with none of the controls. A significantly higher proportion of males had overgrowth than females. There were significant correlations between age at transplant, plaque, bleeding, pocketing and the severity of gingival overgrowth. Many patients with clinically significant gingival overgrowth were apparently unconcerned about this condition.

CONCLUSIONS

It is concluded that gingival overgrowth is a significant problem for renal transplant patients treated with cyclosporin, particularly if they are also treated with a calcium channel blocker. None of the factors measured, in isolation, explained the variable expression of gingival overgrowth in those at risk.

A comparison of the management of potentially malignant oral mucosal lesions by oral medicine practitioners and oral & maxillofacial surgeons in the UK

This study describes the results of a survey undertaken to assess the management of potentially malignant oral mucosal lesions by oral medicine practitioners and compares their approach with that of oral & maxillofacial surgeons that we have previously described. Significant differences were noted between the two groups in the use of photography to document the lesions and in the use of certain special investigations, which included measurement of serum iron, serum ferritin, serum Vit B12, red cell folate and candidal isolation. The groups also varied in the perceived importance of the age of the patient and anatomical site of the lesion when deciding on the need for further biopsy. There was also significant variation in the use of certain treatment modalities, including excising non-dysplastic and severely dysplastic/carcinoma in-situ lesions and eliminating trauma when treating mild/moderately dysplastic and severely dysplastic/carcinoma in-situ lesions. Significant differences in the frequency and duration of follow-up were noted for non-dysplastic lesions. Finally, the two groups differed significantly when asked to rank the perceived importance of certain factors (the histopathology of the most recent biopsy and the anatomical site of the lesion) when deciding the need to follow-up. Possible reasons for the variation are discussed.

Variation in periodontal referral by general dental practitioners

This study investigated the extent of and reasons for variation in the periodontal referral patterns of general dental practitioners in Northern Ireland. A questionnaire was circulated to all general dental practitioners in Northern Ireland. This questionnaire investigated the management of periodontal disease in the general dental service and referral for specialist periodontal advice and treatment. A usable return was made by 355 (68%) of those surveyed. The mean number of periodontal referrals by each respondent in the past year was 6.5 (SD 7.7), range 0 to 80. Backward stepwise logistic regression analysis indicated that independent predictors of high referral rate were practice location close to the referral centre (p<0.0001); dissatisfaction with ability to treat periodontal disease under the National Health Service (p=0.001); that previous refusals of referral had not dissuaded a dentist from continuing to offer referral (p=0.002); not offering root planing as a treatment (p=0.005); and perceived inadequate postgraduate education in periodontology (p=0.03). It is concluded that considerable variation exists between general dental practitioners working in Northern Ireland in relation to the referral of patients for specialist periodontal advice and treatment. It is further concluded that in many cases non-disease factors, such as the accessibility of the specialist service, have powerful effects on the decisions made by dentists and patients in relation to periodontal referral.

Gingival fibroblast response to cyclosporin A and transforming growth factor beta 1

This study investigates a potential role for TGF beta 1 in the pathogenesis of cyclosporin A-induced gingival overgrowth (CsA-OG). TGF beta 1 was localized immunohistochemically in the connective tissue of both normal gingiva and CsA-OG. Intense staining for TGF beta 1 was detected at the tips of the dermal papillae of the overgrown gingiva. In addition, fibroblasts derived from healthy gingiva and fibroblasts derived from CsA-OG were cultured both as monolayers or embedded in a 3D-collagen gel. Fibroblast activity was monitored in terms of protein and collagen production in the presence of (i) 1 ng/ml TGF beta 1, (ii) 500 ng/ml CsA, or (iii) 500 ng/ml CsA and 1 ng/ml TGF beta 1. In monolayer culture TGF beta 1 significantly increased protein and collagen production in all cell strains (p < 0.05); however, there was no difference in response between fibroblasts from overgrown and healthy tissue. The production of both protein and collagen was significantly lower in the presence of the combination of CsA and TGF beta 1 when compared with the maximal stimulation produced by TGF beta 1 alone. In gel, TGF beta 1 significantly elevated matrix production by all overgrown cell strains (p < 0.05) but had little or no effect on the normal cell strains. The combination of CsA and TGF beta 1 in gel cultures reduced protein and collagen production by overgrown cell strains compared with TGF beta 1 alone. It is concluded that the cellular activity of gingival fibroblasts is dependent on culture conditions and that fibroblasts derived from overgrown gingival tissue are more responsive to TGF beta 1 than normal gingival fibroblasts when cultured in type I collagen gel.

Substance P and neurokinin A in gingival crevicular fluid in periodontal health and disease

The aims of the present study were to investigate whether the tachykinins substance P and neurokinin A were present in gingival crevicular fluid in both periodontal health and disease and to study the relationship with periodontal inflammation. Gingival crevicular fluid (GCF) was collected from a healthy, a gingivitis and a periodontitis site in 20 subjects with periodontitis and from a healthy site in 20 subjects without periodontitis. The volume of GCF was measured and each sample subsequently analysed for substance P and neurokinin A by radioimmunoassay. There were significantly increased levels of substance P-like immunoreactivity (SP-LI) and neurokinin A-like immunoreactivity (NKA-LI) in gingivitis and periodontitis sites compared with healthy sites. Both tachykinins were significantly elevated in periodontitis affected subjects, with significantly more tachykinin-like immunoreactivity at healthy sites in periodontitis affected compared with periodontally-healthy subjects. Despite the considerable individual variation in the levels of SP-LI and NKA-LI, both tachykinins were present at levels at which they could have biological activity. It is concluded that substance P and neurokinin A may have a rôle in the pathogenesis of periodontal disease and that further investigations could prove useful in clarifying the mechanisms through which neuropeptides could modulate periodontal health and disease.

Molar furcation involvement associated with cigarette smoking in periodontal referrals

The aim of this study was to investigate the relationship between cigarette smoking and furcation involvement in molar teeth. A consecutive group of 50 smokers were recruited from referrals to a periodontal clinic and age and gender matched with never smokers. Smokers consumed an average of 18.0 (SD 6.7) cigarettes per day and had smoked for 2.7 (SD 6.5) years. Radiographs of all molar teeth were assessed 2 x by an examiner blinded to the smoking status. Smokers had slightly fewer molar teeth 6.7 (SD 2.6) than the never smokers, 7.3 (SD 2.3), t = 1.2, P = 0.22. More smokers (72%) had evidence of furcation involvement than never smokers (36%), x2 = 13.0, P = 0.0003. The odds ratio for a smoker having 1 molar with furcation involvement was 4.6 (c.i. 2 - 10.6). Smokers had more molars with furcation involvement 1.94 (SD 1.7) compared with never smokers, 0.94 (SD 1.4), t = 3.1, P = 0.003. It is concluded that cigarette smoking is associated with a greater expression of molar furcation involvement in periodontitis affected subjects.

Stress and the progression of periodontal disease

This study examined the association between occupational stress and the progression of periodontitis in employed adults. 23 regular dental attenders, enrolled in a longitudinal study of periodontal disease, were examined on 2 occasions at an interval of 5.5 (SD 0.6) years. The mean age at the 2nd examination was 41.1 (SD 7.3) years. Clinical measurements of periodontal status including clinical attachment level were made at four proximal sites on all teeth. A questionnaire, the occupational stress indicator, was used at the second examination to assess stress retrospectively. The mean change in clinical attachment level was 0.63 (SD 0.42) mm and 9.6 (SD 8.6)% of sites measured at both examination lost > or = 3 mm of periodontal attachment. Multiple regression analysis was used to explore the relationship between mean loss of periodontal attachment and measures of occupational stress and sociodemographic data. In the final regression model, an increase in loss of periodontal attachment was significantly predicted by increasing age, lower socio-economic status, lower job satisfaction and type A personality. In addition, locus of control was included in the regression model which explained 65% of the variance in the loss of periodontal attachment. The results suggest that occupational stress may have a relationship to the progression of periodontitis.

The clinical performance of cantilevered resin-bonded bridgework

OBJECTIVES

The technique of resin-bonded bridgework is a well-accepted clinical technique to replace missing teeth. This study assesses the clinical performance of cantilevered resin-bonded bridgework provided in a university teaching hospital environment.

METHODS

One-hundred and twelve patients who had a total of 142 cantilevered bridges were either examined or completed a questionnaire regarding their bridgework. The following data were recorded for each resin-bonded bridge: gender of patient, age at bridge cementation, date of initial cementation, tooth replaced, abutment(s) involved, and grade of clinician responsible for the provision of the bridge. Details of the incidence of debonding with date(s) and the subsequent treatment in relation to the debonded resin-bonded bridge were recorded. The subjects examined indicated their degree of satisfaction with their bridgework on a visual analogue scale.

RESULTS

There were 112 patients with a total of 142 bridges, 116 (82%) maxillary and 26 (18%) mandibular. The mean length of clinical service was 36.2 months (s.d. 17.2 months). Only single pontics were included in the bridges, with almost half (49%) replacing a lateral incisor. Of the cantilever resin-bonded bridges studied, 88% remained bonded over the period of the study. A success rate of 94% is reported.

CONCLUSION

This study confirms the clinical success of cantilever resin-bonded bridges particularly in the replacement of maxillary lateral incisors, maxillary premolar and permanent mandibular teeth.

Management of potentially malignant oral mucosal lesions by consultant UK oral and maxillofacial surgeons

This paper describes the results of a recent survey carried out under the auspices of the Professional Education and Evaluation Subgroup of the UK Working Group on Screening for Oral Cancer and Precancer. The aim of this survey was to assimilate information regarding currently used management options of potentially malignant oral lesions as a basis from which to rationalise our future approach to their management. The survey has confirmed that variation exists among oral and maxillofacial consultants in their approaches and a more formal approach to management may therefore be indicated.

The clinical success and periodontal evaluation of patients rehabilitated with light-cured obturators

The clinical performance of a visible light-cured (VLC) resin for obturators was evaluated in 10 patients. All patients had undergone ablative surgery of the maxilla, previously worn conventional heat-cured hollow bulb acrylic obturators and were currently rehabilitated with VLC obturators. The obturators were assessed on their performance for each of the following: weight, retention, speech, eating and comfort. An evaluation of the periodontal status of those who retained teeth in the maxilla was also performed. It is concluded that patients found VLC obturators to have a more acceptable clinical performance than conventional acrylic obturators due primarily to a reduction in appliance weight.

Dental anxiety and the absorption of orally administered erythromycin stearate

Erythromycin stearate is an acid labile antibiotic, therefore fear and apprehension, which are known to affect gastric motility, may produce erratic absorption resulting in lower serum levels. The mean (SD) serum erythromycin concentration 75 minutes after a 1.5 gm oral dose of erythromycin stearate to 45 patients was 8.7 (4.8) mg/L and ranged widely from 0.4 to 20.5 mg/L. The serum concentration of erythromycin was below therapeutic levels (1.0 mg/L) in two patients. No significant association was found between anxiety and serum levels of erythromycin when age, gender, and gastric distress were taken into account. It is concluded that dental anxiety may indirectly influence the uptake of oral erythromycin stearate; but this relationship is complex, and there is no evidence from this study that increased dental anxiety decreases the uptake of the drug.

The efficacy of a herbal-based toothpaste on the control of plaque and gingivitis

A double-blind controlled clinical trial with parallel groups was designed to investigate the effectiveness of a herbal-based toothpaste in the control of plaque and gingivitis as compared with a conventional dentifrice. 70 subjects with gingivitis completed the 6-week study. All participants had at least 20 natural teeth with no probing depths greater than 3 mm and a plaque index of 2 or more at baseline. At baseline, both groups were balanced for the parameters measured: plaque index, plaque vitality, gingival index, bleeding on probing and gingival crevicular fluid flow. At the end of the trial, there were reductions within both groups, however, there were no significant differences between the groups. It was concluded that the herbal based toothpaste was as effective as the conventionally formulated dentifrice in the control of plaque and gingivitis.

A feasibility study on the use of direct light silver stain compared with dark field microscopy for differential counting of subgingival plaque

The purpose of the present study was to compare direct light microscopy using a silver stain, with dark field microscopy for differential counting of subgingival plaque samples from patients with periodontitis. The feasibility of using the staining method was assessed on subgingival plaque samples which were collected at 34 sites from patients with untreated adult periodontitis. Differential counts of plaque morphotypes assessed by both methods showed close agreement. The proportions of spirochaetes assessed by both methods were significantly associated with probing depth. The silver stain proved a simple, rapid and inexpensive method for differential counting of plaque composition. This method is suitable for possible use in general dental practice where smears could be made at the chair-side and allowed to dry ready for staining and counting at the dentist's convenience using a simple light microscope. A permanent record is also produced which could allow for comparison of samples from before and after treatment and could be used as an aid to patient motivation in suitable cases.

The effects of culture environment on the response of human gingival fibroblasts to cyclosporin A

In contrast to monolayer cell culture, the use of a 3-dimensional culture system creates an environment which is more physiologically comparable to conditions in vivo. This study aimed to investigate the effects of culture environment on growth and protein biosynthesis by 6 human gingival fibroblast cell lines exposed to cyclosporin A (CsA). Fibroblasts were grown both in monolayer culture on plastic and embedded within collagen gel. Cyclosporin A was added to cultures at a range of concentrations between 10(-5) and 10(-9) g/ml. Under both culture conditions CsA had little effect on cell growth at low concentrations but at the highest concentration of 10(-5) g/ml, there was a significant inhibitory effect on growth (P < 0.05). Protein production was not significantly affected by CsA in either culture system. Total collagen production appeared to be inhibited at high concentrations of CsA when cells were grown on plastic but remained unaffected when the cells were grown in collagen gel. Total protein and collagen production per cell in collagen gel was substantially greater compared with cells grown on plastic. We conclude that under the conditions of this investigation CsA did not directly stimulate growth or matrix-synthesis by normal human gingival fibroblasts cultured in 3-dimensional collagen gel or as monolayers on plastic.

The periodontal status of irregular dental attenders

The aim of this investigation was to assess the prevalence and severity of periodontal destruction in irregular dental attenders. 50 subjects aged between 20 and 49 years completed a questionnaire and had a periodontal examination. Measurements of plaque, calculus, bleeding, probing depth and clinical attachment level were made at 4 proximal sites per tooth. Results were compared to those for 132 regular attenders. The irregular attenders had more sites with plaque (46.3 +/- 27% versus 17.3 +/- 21.1%) than the regulars and significantly more sites which bled (53.7 +/- 20.4% versus 33.6 +/- 20.7%) and with calculus (35 +/- 21.1% versus 13.4 +/- 12.8%). However, the irregulars had virtually the same number of teeth as the regular attenders, 25.6 +/- 3.3 compared with 25.4 +/- 4.3. Irregular attenders had slightly deeper mean probing depths (2.9 +/- 0.4 versus 2.7 +/- 0.4 mm) but the prevalence and extent of attachment loss was no different between the groups. It was concluded that the prevalence and severity of destructive periodontal disease as indicated by periodontal attachment loss was not related to the regularity of dental attendance in the groups studied.

Cigarette smoking and periodontal destruction in young adults

The relationship between cigarette smoking and periodontal destruction was assessed in young adults. Eighty-two regular dental attenders (21 current cigarette smokers, 61 non-smokers) aged between 20 and 33 years were examined. The smokers consumed on average 15.4 (+/- 7.3) cigarettes per day and had smoked for an average of 11.8 (+/- 7) years. Cigarette smokers had almost the same levels of plaque as non-smokers but had more proximal surfaces with subgingival calculus (P < 0.01) and which bled on probing (P < 0.05). Smokers had significantly more pockets > or = 4 mm (14.6 +/- 19.9) than non-smokers (5.8 +/- 7.9), P < 0.01. Only 2 (10%) of the smokers and 1 (2%) of the non-smokers had deep pocketing (> or = 6 mm). Smokers had significantly more sites (21.8 +/- 24.9) with periodontal attachment loss of > or = 2 mm than non-smokers (9.3 +/- 12.2), P < 0.01. Severe loss of periodontal attachment (> or = 6 mm) was present in 4 (19%) of smokers compared with 2 (3%) of non smokers. In total 4 (19%) of the smokers had "established periodontitis" compared with 1 (2%) of the non-smokers. The odds ratio for the presence of "established periodontitis" and smoking was 14.1 (confidence interval 1.5 to 132.9). It is concluded that cigarette smoking was a major environmental factor associated with accelerated periodontal destruction in this selected group of young adult regular dental attenders.

Periodontal status of regular dental attenders with and without removable partial dentures

The periodontal status of 14 regular dental attenders who had been wearing removable partial dentures was compared with a matched group of non-denture wearers. Most partial dentures were mucosally supported. Reported plaque control practices, levels of plaque, subgingival calculus and gingival bleeding, mean pocket depth and mean loss of periodontal attachment were similar in both groups. Severe destructive periodontal disease was present in five (36%) of the denture wearers compared with seven (50%) of the non-denture wearers. We conclude that regular dental attenders with partial dentures were no more likely to have poorer periodontal health than comparable non-denture wearers.

Comparative reproducibility of proximal probing depth using electronic pressure-controlled and hand probing

This investigation assessed the effect of an electronic pressure-sensitive probe on the reproducibility of probing-depth measurement. Clinical measurements were made at the mesial and distal aspects of all teeth from the buccal and palatal or lingual aspects. Probing was carried out either in a conventional manner using gentle pressure referred to as hand probing or using an electronic pressure-sensitive probe set at 25 g and referred to as pressure-controlled probing. Probing-depth recordings were repeated for one randomly selected quadrant in each subject with random application of the 4 different combinations of pressure-controlled and hand probing. A total of 2584 replicate pairs of probing depth measurements were recorded on 4 proximal surfaces in 646 teeth in 100 adult subjects. The majority (98%) of all repeated measurements were within 1 mm of the initial values. The highest levels of agreement resulted when the same probing method was used at both examinations with electronic pressure-controlled probing being superior to hand probing regardless of tooth position or site. Duplicate measurements recorded with combinations of hand and pressure-controlled probing showed significant systematic bias towards shallower pocket depths with electronic pressure-controlled probing.

Candidal infection as a complication of barrier membrane placement in a diabetic patient

This report describes candidal infection as a complication of barrier membrane placement in a diabetic patient. This resulted in failure of the regenerative procedure and necessitated extraction of the tooth involved. Candidal hyphae were demonstrated within the dentinal tubules of the tooth. Subsequent to appropriate medical treatment to regain control of the diabetes there was an improvement in oral health.

Nifedipine-induced gingival hyperplasia

This case study reports on the management of a woman suffering from thrombocytopenic purpura who was referred to the periodontal clinic with gingival swelling and bleeding. This condition was related to nifedipine therapy for hypertension.

The effect of partial denture connectors on gingival health

The effect on the gingiva of a variety of relationships of a removable partial denture connector to the gingival margin was investigated in 10 subjects. Acrylic resin baseplates were designed incorporating a variety of relationships of the connector to the gingival margin. The appliances were worn for a 12 hour period daily, for 21 days. At baseline and at days 7, 21 and 49, plaque index, gingival index and probing pocket depth measurements were recorded, and subgingival plaque samples were examined using darkfield microscopy. No increase in plaque accumulation was detected in any area at any time interval. There was a significant increase in gingival index at day 21 in areas where the appliance covered the gingival margin. Small increases in probing pocket depth were recorded at day 21, there being no difference between any of the test areas. Baseline values were re-established by day 49. No significant differences were detected in the percentage of motile organisms or spirochaetes counted in the subgingival plaque samples collected from any area. It was concluded that deterioration in gingival health occurred rapidly following the insertion of a removable appliance, and that coverage of the gingival margin, irrespective of the degree of gingival relief, had a detrimental effect.

Overhanging amalgam restorations in young adults attending a periodontal department

An important factor affecting plaque retention is the presence of amalgam restorations which are poorly contoured at the gingival margin. The aim of the study was to investigate the occurrence and effects of overhanging amalgam restorations in young adults. One hundred patients, aged 20-29 years, referred to the Periodontal Department, School of Dentistry, Belfast were investigated. Bitewing radiographs were used to examine the restorative status of the approximal surfaces of premolar and permanent molar teeth, excluding third molars. Fifty-seven per cent of the patients investigated had at least one amalgam overhang and 27 per cent had three or more overhangs visible on the radiographs. One hundred and seventy-eight (25 per cent) of the restored approximal surfaces had detectable amalgam overhangs. The mean bone level-amelocemental junction (ACJ) distance related to the approximal surfaces with overhangs was 1.77 (s.d. 1.0) mm and 37 (32 per cent) of these surfaces had bone levels which were greater than 2 mm from the ACJ. The mean bone level-ACJ distance for the other approximal surfaces of the teeth with overhangs was 1.63 (s.d. 1.2) mm. The mean bone level-ACJ distance for matching control surfaces on contralateral teeth was 1.86 (s.d. 1.2) mm. It was concluded that overhanging amalgam restorations were common in the restorations of young adults (20-29 years old) referred for periodontal treatment but were not associated with increased levels of bone destruction.

The periodontal condition of regular dental attenders in Northern Ireland

The aim of this study was to assess the prevalence and severity of periodontal destruction in regular dental attenders in Northern Ireland. 132 individuals aged between 20 and 49 years who had recently had a course of routine treatment in the General Dental Service completed a questionnaire and had a periodontal examination. Measurements of plaque, subgingival calculus, bleeding, probing pocket depth and periodontal attachment level were made at 4 proximal sites per tooth. Plaque was present at an average of 17%, subgingival calculus at 13%, and bleeding on probing at 34% of interproximal surfaces examined. The mean probing pocket depth was 2.7 mm and the mean probing attachment level was 1.0 mm. Incipient periodontal destruction was common with all subjects having at least 1 pocket of greater than or equal to 3 mm and 90% having at least 1 site with greater than or equal to 2 mm attachment loss. Only 24 (18%) of those examined had deep pocketing or severe loss of periodontal attachment (greater than or equal to 6 mm). The extent of deep pocketing and severe attachment loss was low at only 0.2% and 0.6%, respectively, of the sites examined. It was concluded that gingivitis and incipient periodontitis were prevalent and extensive in the regular dental attenders investigated, but that severe periodontal destruction was uncommon.

Knowledge, attitudes and behaviour in relation to dental health of adults in Belfast, Northern Ireland

The aim was to investigate the knowledge, attitudes and behaviour related to dental health of adults living in two neighbouring areas in Belfast, Northern Ireland. 81 adults aged 30 yr or over from two neighbouring residential areas in South Belfast completed a structured interview. The responses of those who retained natural teeth were very different from those who were edentulous. Those in the higher socioeconomic status groups had clearer knowledge, more positive attitudes and more appropriate behaviour related to dental health than those in lower socioeconomic status groups. The differences between the residents of the two areas were less obvious than those noted between the different socioeconomic status groups. It was concluded that the results revealed misconceptions amongst adults in Northern Ireland regarding the causes of dental disease and how it might be prevented both in themselves and in their children.