Oral lichenoid lesions related to dental restorative materials.

OBJECTIVES: To determine the effectiveness of replacing restorations considered to be the cause of an oral lichenoid lesion (oral lichenoid reaction)(OLL). DESIGN: Clinical intervention and nine-month follow up. SETTING: The study was carried out in the University Dental Hospital of Manchester, 1998-2002. SUBJECTS AND METHODS: A total of 51 patients, mean age 53 (SD 13) years, who had oral lesions or symptoms suspected to be related to their dental restorations were investigated. Baseline patch tests for a series of dental materials, biopsies and photographs were undertaken. Thirty-nine out of 51 (76%) of patients had their restorations replaced. RESULTS: The clinical manifestations of OLL were variable; the majority of OLL were found to be in the molar and retro molar area of the buccal mucosa and the tongue. Twenty-seven (53%) patients had positive patch test reactions to at least one material, 24 of them for one or more mercury compound. After a mean follow up period of nine months, lesions adjacent to replaced restorations completely healed in 16 (42%) patients (10 positive and 6 negative patch tests). Improvement in signs and symptoms were found in 18 (47%) patients (11 positive and 7 negative patch tests). CONCLUSION: OLLs may be elicited by some dental restorations. Replacing restorations adjacent to these lesions is associated with healing in the majority of cases particularly when lesions are in close contact with restorations. A patch test seems to be of limited benefit as a predictor of such reactions.

Mercuric chloride: toxicity and apoptosis in a human oligodendroglial cell line MO3.13.

A human-human oligodendroglial cell line MO3.13 was chosen in this study to model the loss of oligodendrocytes that occurs during episodes of multiple sclerosis. The influence of mercuric chloride (HgCl(2)) upon cell viability specifically the mode of cell death, whether by an active apoptotic mechanism or passive necrosis was determined by morphological and biochemical analysis. Mitochondrial dehydrogenase activity MTT assay showed that HgCl(2) had toxic effects on MO3.13 cells at levels of (5-25 microM) with approximately 50% cell death observed at 58 microM. Death of cells was dependent on both time and concentrations of HgCl(2). Differentiated MO3.13 cells exposed to low concentrations (25 microM) of HgCl(2) exhibited features of apoptotic cell death, including cell shrinkage and chromatin condensation. High doses of HgCl(2) (>100 microM) induced death with characteristics of necrosis. Biochemical analysis showed that HgCl(2) activated the caspase family of proteases. This was measured directly by cleavage of fluorescent substrates and by immunoblotting assay of caspase substrate proteins; alpha-fodrin, lamin B and poly (ADP-ribose) polymerase (PARP). These results indicate that HgCl(2) is toxic at low concentrations for oligodendroglial cells and that the MO3.13 cell line dies in an apoptotic manner when exposed to low concentrations of HgCl(2). However, blood mercury concentrations in vivo in a normal population with amalgam restorations are lower by a factor of some 500 times than those causing toxicity in vitro suggesting a good safety margin in respect of environmental uptake.

Screening programmes for the early detection and prevention of oral cancer.

BACKGROUND: Although the second half of the last century has generated a rich and complex body of knowledge, the burden of oral cancer is still largely present. As with other cancers, there has been a strong debate whether screening strategies for oral cancer such as visual examination, the use of toluidine blue or newer methods such as brush biopsy or fluorescence imaging are effective in reducing the mortality rate associated with oral cancer. OBJECTIVES: To assess the effectiveness of current screening methods in decreasing oral cancer mortality. SEARCH STRATEGY: Electronic databases (MEDLINE, CANCERLIT, EMBASE, the Cochrane Central Register of Controlled Trials; 1966 to September 2002, The Cochrane Library - Issue 2, 2002), bibliographies, handsearching of specific journals and contact authors were used to identify published and unpublished data. SELECTION CRITERIA: Randomised controlled trials of screening for oral cancer or potentially premalignant oral lesions using visual examination, toluidine blue, fluorescence imaging or brush biopsy. DATA COLLECTION AND ANALYSIS: The search found 100 citations and these have been reviewed. One randomised controlled trial of screening strategies for oral cancer was identified as meeting the review's inclusion criteria. Validity assessment, data extraction and statistics evaluation have been undertaken by two independent reviewers. MAIN RESULTS: One ongoing randomised controlled trial has been included (n = 13 clusters: 153,708 eligible subjects, 130,799 included subjects). There was no difference in the age-standardised oral cancer mortality rates for the screened group (21.2/1000,000 person years) and the control group (21.3/100,000 person years). However this study has some methodological weaknesses. REVIEWER'S CONCLUSIONS: Given the limitation of evidence (only one included randomised controlled trial) and the potential methodological weakness in the included study, it is valid to say that there is no evidence to support or refute the use of a visual examination as a method of screening for oral cancer using a visual examination in the general population. Furthermore, no robust evidence exists to suggest other methods of screening, toluidine blue, fluorescence imaging or brush biopsy, are either beneficial or harmful. Further cost-effective, high quality studies to assess the efficacy and effectiveness of screening are required. In addition, studies to elucidate the natural history of oral cancer, prevention methods and the effectiveness of opportunistic screening in high risk groups are needed.

Resin composite monomers alter MTT and LDH activity of human gingival fibroblasts in vitro.

OBJECTIVES: Substances such as monomers may be released from composite resin systems and may induce adverse effects in biological tissues. The aim of this study is to investigate the cytotoxic concentrations of resin composite monomers on cultures of human gingival fibroblasts. METHODS: A range of dilutions of five resin composite monomers (HEMA, HPMA, DMAEMA, TEGDMA, and Bis-GMA) were added to the culture medium of human gingival fibroblasts for 24 h. Their cytotoxic effects were measured by using two colorimetric functional assays, mitochondrial dehydrogenase activity (MTT) and lactate dehydrogenase activity (LDH) assay. The logP values (water/octanol partition) of test monomers were also calculated computationally. RESULTS: Mitochondrial reducing activity assessed with the MTT test was inhibited by all monomers and all the monomers increased the LDH release in a reproducible dose dependent manner. A wide range of TC 50 values (concentrations altering MTT and LDH activity by 50%) (0.32-5.8 mM by MTT assay and 0.36-6.7 mM by LDH assay) was observed. Ranking of composite resin monomer cytotoxicities (TC 50) were similar for both the MTT and LDH assays, (Bis-GMA>TEGDMA>DMAEMA>HPMA >HEMA). However, the MTT assay was found to be more sensitive than the LDH assay, particularly when lower doses of the tested monomers were determined. The ranking of TC 50 concentrations correlated with the calculated logP values. SIGNIFICANCE: Monomers used in dental restorative materials show a variety of toxic effects on gingival fibroblasts. A combination approach using MTT and LDH assays provides valuable information about their toxic effects.

Healing of oral lichenoid lesions after replacing amalgam restorations: a systematic review.

OBJECTIVE: We sought to systematically review the literature related to oral lichenoid lesions (OLLs) and amalgam restorations. STUDY DESIGN: Cohort and case-controlled studies (no randomized controlled trials or controlled clinical trials available) were reviewed with respect to inclusion criteria and data on patients with OLLs, treatment interventions, and the measurement of outcomes. RESULTS: Fourteen cohort and 5 case-controlled trials met the criteria. The study population consisted of 1158 patients (27% male and 73% female; age range, 23-79 years). From 16% to 91% of patients had positive patch test results for at least 1 mercury compound. Of 1158 patients, 636 had to have their restorations replaced. The follow-up period ranged from 2 months to 9 1/2 years. Complete healing ranged from 37.5% to 100%. The greatest improvements were seen in lesions in close contact with amalgam. CONCLUSIONS: Protocols must be standardized to obtain valid results. The replacement of amalgam restorations can result in the resolution or improvement of OLLs. Patch testing seems to be of limited value. The topographic relationship between an OLL and an amalgam restoration is a useful--but not conclusive--marker.

Ecstasy--dental implications.

Ecstasy (also known as 'love drug', 'XTC' or 'E') is the name commonly used for the illegal designer drug related to amphetamine, 3,4 methylenedioxy-methamphetamine (MDMA). MDMA was patented in 1914 as an appetite suppressant, has been investigated as a mood modifying agent, but with its predecessor 3,4 methylenedioxyamphetamine (MDA) is now widely (and wrongly), promoted as a safe, non-toxic means to 'warm loving relaxation'.

Dental prescribing: minimising the cost to the patient and the NHS.

The high cost of prescription charges, changes in drug availability and the increase in private and independent dental practice means that NHS prescriptions may not be the cheapest or most appropriate way of providing drugs to patients. This article examines this complex area and provides some practical advice.

Attitudes to biopsy procedures in general dental practice.

AIM: To investigate biopsy procedures in general dental practice. OBJECTIVES: To assess the views and attitudes of: specialists on the dental specialist surgical registers; dentists in general practice (GDPs) and patients undergoing biopsy procedures. METHOD: Questionnaires were sent to 98 oral and maxillofacial surgeons and surgical dentists, 335 general dental practitioners and 220 patients attending the Oral Medicine Clinic at the Dental Hospital, Manchester. Participation rates were 68 (74%), 227 (72%), and 158 (76%) respectively. RESULTS: Specialists: 47 (70%) would discourage dental practitioners undertaking biopsies. Concerns were a lack of skills and delays in referral; 20 (30%) considered GDPs should be able to perform simple biopsies for benign lesions. Dentists: 33 (15%) reported they had performed oral biopsies in the last two years; 136 (60%) felt they should be competent to biopsy benign lesions. Their main concerns were lack of practical skills and the risk of diagnostic error. PATIENTS: 112 (65%) worried about their biopsy result, 67 (39%) would feel anxious if their dentist did the biopsy, although 40 (23%) were anxious when biopsied in the oral medicine clinic. CONCLUSIONS: Both specialists on the dental surgical registers and GDPs feel there is a need for further training in biopsy technique for GDPs and better advertised and accessible pathology support. The current fee for biopsies may need upward revision. A main concern of patients is fear of an adverse biopsy report. Whilst patients are satisfied with specialist management any concerns were an insufficient reason for biopsy of a benign lesion not being undertaken in general practice.

A double-blind cross-over trial of a mucin-containing artificial saliva.

A double-blind, five phase, cross-over clinical trial was used to compare a mucin-based artificial saliva (Saliva Orthana) with its non-mucin base and water. Thirty patients, acting as their own controls, took part. Saliva Orthana offered significantly greater relief from xerostomia compared with its base or water, and was significantly better at relieving soreness than water. In terms of overall preference, it was ranked significantly higher than either alternative.

Persistent impairment of taste associated with terbinafine.

A second case of persistent taste disturbance associated with terbinafine is described. Taste disturbance associated with this drug is reviewed and a table is provided listing the more common drugs associated with taste disturbance.

Opinions of UK specialists about terminology, diagnosis, and treatment of atypical facial pain: a survey.

There are few robust, evidence-based data about what constitutes the diagnosis of atypical facial pain and how it is best treated. We therefore aimed to find out the current opinion of those on specialist lists in the United Kingdom (UK) on whether they use the term atypical facial pain, how they reach their diagnosis, and what treatment they offer. We sent out questionnaires to 240 specialists randomly selected from the UK lists of those most likely to deal with atypical facial pain (oral and maxillofacial surgeons, oral medical specialists, ear nose and throat surgeons, anaesthetists, psychiatrists and neurologists). We divided the replies according to whether the specialists were medically or dentally based. Of the 209 valid questionnaires, 143 were returned (a response rate of 68%); 127 of the 143 used the term atypical facial pain, the others used various other terms. The two groups used significantly different criteria, mainly to exclude other conditions to achieve a diagnosis. About half used haematological tests and most used radiographic investigations routinely, and there were no significant differences among the specialities. No unified pattern of referral between different units was found. Treatment was mainly by antidepressant and anticonvulsant drugs, and counselling.

Oral contraceptives and the dental practitioner.

PIP: Oral contraceptives (OCs) may influence or effect dental treatments in several ways. OC preparations containing estrogen and progestogen inhibit ovulation by an action on the hypothalamus. Progestogen also produces local effects on the endometrium, cervical mucus and possibly uterine tubes. A number of drugs commonly used by dentists reduce OC effectiveness. Pregnancies have been reported among OC users taking ampicillin and tetracycline, which are suspected to interfere with the enterohepatic recirculation of steroids or enzyme induction. Phenoxymethylpenicillin should also be used with caution. Breakthrough bleeding and pregnancy have been associated with chlordiazepoxide. Antihistamines and carbamazepine may also reduce OC effectiveness. OCs may increase sensitivity to pethidine and reduce serum cholinesterase levels. 5% of the dental patients in Great Britain may be taking OCs and dentists should inform patients of possible drug interactions. OC overdose has been associated with hypertrophic gingivitis, marked gingival erythema, bleeding and pregnancy-type epulis. In normal doses, they may cause gingivitis with an increase in gingival exudate and in the number of inflamed papillae. In general, clinical manifestations of OC use are nonexistent or minimal. An increased incidence of postoperative localized osteitis following the removal of mandibular 3rd molars in patients taking OCs is reported and could be avoided if surgery was done prior to the use of OCs or possibly was conducted during a period of abstinence. Menstrually related oral ulceration has been successfully treated with OCs, however, this treatment is suggested only following definitive diagnosis.^ieng