Martin M. Ferguson

The Effect of Chlorhexidine and Benzydamine Mouthwashes On Mucositis Induced by Therapeutic Irradiation

A variety of mouthwashes are frequently used in the management of irradiation-induced mucositis. Benzydamine has recently been introduced for alleviating this condition. Its efficacy as a mouthwash was compared with chlorhexidine in two groups of patients receiving radiotherapy for oral carcinoma. Mucositis and pain were recorded over a 6 week period and oral carriage of Candida species, coliforms and Staphylococcus aureus was assessed using an oral rinse technique. There was no significant difference in the mucositis scores, overall pain scores or the yeast and bacterial species isolated between the two treatment groups. However, 58% (7 out of 12) and 92% (12 out of 13) patients reported oral discomfort when rinsing the mouth with chlorhexidine and benzydamine, respectively. In both groups, the most common coliform isolated was Klebsiella pneumoniae and the carriage of yeasts was significantly greater than that of coliforms. These results indicate that, although the individual patient acceptance of chlorhexidine is better than benzydamine, there is little difference between the two mouthwashes both in controlling pain and mucositis or in the oral carriage of the micro-organisms studied.

Pilocarpine and other cholinergic drugs in the management of salivary gland dysfunction

Sialagogues constitute an important component in the management of salivary gland dysfunction. Of the pharmacologic agents available, pilocarpine has been used extensively over the last century. Many clinical trials have documented the efficacy of this alkaloid, with doses that range from 1 to 15 mg normally taken four times a day. There is considerable individual variation in response although it is usually possible, in the presence of sufficient responsive exocrine tissue, to establish a therapeutic regimen that promotes increased salivation without significant side effects.

ORAL LICHENOID REACTIONS RELATED TO MERCURY SENSITIVITY

Lichen planus is a common disorder of unknown aetiology. It has been proposed that in some cases it represents a form of allergic reaction to the metals contained in dental amalgam, particularly mercury. Twenty-nine consecutive dentate patients who had lichen planus of the oral mucosa were patch-tested to the range of metals contained in dental amalgam. Ten out of 29 (34%) showed an allergic reaction to mercury and all of these patients had amalgams greater than 5 years old. The amalgams were poorly contoured and had corroded, resulting in continued release of mercury ions. Six patients had their amalgams replaced with composite or glass ionomer materials resulting in resolution of ulcerated lesions. In a follow-up of 3-24 months, one patient had a recurrence of ulcerated areas and another, despite resolution of the oral lesions had persistent discomfort.

Delivery of antifungal agents to the oral cavity

Abstract There is scant information in the literature on the local delivery of antifungal agents within the mouth. Research, therefore, is warranted to evaluate the optimal vehicle for the delivery of the agents to the oral mucosa. A major difficulty for the successful eradication of fungal infections appears to be the dilution and rapid elimination of the drugs from the oral cavity due to the flushing action of saliva. This problem may partly be circumvented by the discovery of the newer triazoles which appear to be effective for most oral candidoses, with only a single dose administration per day and the drug delivered via the systemic route. Nonetheless, whether such newer drugs, with a wide spectrum of activity and minimal toxicity, should be used routinely for oral candidoses merits consideration as emergence of resistant organisms to the triazoles have been now been reported. Accordingly, topical delivery of antifungals remains the most widely accepted approach, with techniques aimed at prolonging drug inhibitory concentrations in the oral cavity. Since most antifungals do not possess inherent ability to bind to oral mucosa, this goal may best be achieved through improved formulations.

Effects of dietary gluten elimination in patients with recurrent minor aphthous stomatitis and no detectable gluten enteropathy

Fifty patients with a history of minor recurrent aphthous stomatitis were entered into a 6-month double-blind controlled trial of a gluten-free diet. After hematologic and biochemical investigations and jejunal biopsy, one half of the group was given a gluten-free diet; the other half served as controls and received a gluten-free diet supplemented by gluten given blind (control diet). Twenty-three patients completed the trial, 11 patients on a gluten-free diet, 12 on the control diet. Four of the 11 on the gluten-free diet and 7 of the 12 on the control diet reported significant benefit in terms of minor recurrent aphthous stomatitis, but there was no statistical difference between the responses. The results fail to support studies that report widespread benefit in aphthae of gluten withdrawal and suggest simply a marked placebo response in the condition.

Testicular lipomatosis in Cowden's syndrome.

Cowdens syndrome is either familial or sporadic and is associated with the predominantly postpubertal development of a variety of cutaneous, stromal and visceral neoplasms. The syndrome is associated with mutations of the PTEN gene and is closely related to Bannayans syndrome in which macrocephaly and benign tumors, especially lipomas and hemangiomas are pathognomic. In PTEN knockout mice testicular tumors have been reported and for this reason we felt it prudent to examine the testes of our patients with genetically proven Cowdens syndrome. Seven of eight patients who underwent testicular ultrasound were found to have diffuse bilateral hyperechoic lesions. Four patients consented to testicular biopsy and on histological examination multiple foci of adipocytes were found within the testicular interstitium, with no evidence of dysplasia or preclinical malignancy. Immunohistochemical assessment of adipocytes suggested a stromal derivation without evidence of metaplasia from Leydig cells. In one case there was focal atrophy of seminiferous tubules, while in two others there was nodular periorchitis of the tunica albuginea. Biochemical evaluation of testicular function (luteinizing hormone, follicle-stimulating hormone, testosterone, sex hormone binding globulin and free androgen index), prostate-specific antigen and testicular tumor markers were normal, while seminal fluid analysis showed only minor abnormalities. The high incidence of testicular lipomatosis in our adult subjects suggests this to be an important diagnostic criterion for Cowdens syndrome.

A case of Sweet’s syndrome (acute febrile neutrophilic dermatosis) with palatal ulceration

tosis), which was first described in 1964 by Sweet,1 is characterized by 4 cardinal features: 1) fever, 2) a relative increase of neutrophils in the peripheral blood, 3) skin lesions such as tender erythematous plaques, nodules, vesicles, and pustules on the face and extremities, and 4) a dense dermal infiltrate with mature neutrophils seen histologically. It has been reported that Sweet’s syndrome is often accompanied by oral lesions1 but details of oral findings in Sweet’s syndrome are rarely reported. A case of Sweet’s syndrome occurring in a middleaged woman with a large palatal ulcer is presented.

A pilot study of the disposition of pilocarpine in plasma, saliva and urine after a single oral dose

Concentrations of pilocarpine in plasma, saliva and urine from three healthy male volunteers were measured using a fluorescence derivatisation method, following administration of a single 10 mg oral dose. Pharmacokinetic parameter values were estimated from concentration-time profiles. Linear correlations between plasma and saliva pilocarpine concentrations (r2=0.945, n=10, p<0.001; r2=0.954, n=12, p<0.001) and plasma concentrations and salivation rate (r2=0. 863, n=12, p<0.001; r2=0.862, n=15, p<0.001) were established. Pilocarpine and an unidentified metabolite, respectively 20.3% and 34.7% of the oral dose, were excreted into urine.

Distribution of mutations distinguishing the most prevalent disease-causing Candida albicans genotype from other genotypes.

Candida albicans is a major opportunistic pathogen of humans. Previous work has demonstrated the existence of a general-purpose genotype (GPG; equivalent to clade 1 as defined by multi-locus sequence typing data) that is more frequent than other genotypes as an agent of human disease and commensal colonization. We undertook a genomic screen which indicated that a large number of mutations differentiate GPG strains from other strains and that such mutations are scattered throughout the genome. GPG-specific mutations are non-synonymous more frequently than expected by chance, and are not randomly distributed across functional and structural gene categories. Our analysis has identified three categories of genes in which GPG-specific mutations are over-represented, namely genes for which expression changes during the yeast-hyphal transition, genes for which expression changes as a result of exposure to antifungal agents and repeat-containing ORFs. Although we have no direct evidence that the individual polymorphisms identified confer selective advantages to GPG strains, the results support our contention that the high prevalence of GPG strains is not merely due to genetic drift but that GPG strains have reached a high prevalence because they possess a multitude of fitness-enhancing traits. They also indicate that the distribution of genes marked by GPG-specific mutations across functional and structural categories could identify physiological traits that are of particular importance to the success of GPG strains in their interactions with the human host.

Saliva substitutes in the management of salivary gland dysfunction

Abstract Salivary gland dysfunction is a relatively common problem which results in the symptoms of a dry or scalded mouth, difficulties with speech, problems with eating, mucosal infections, denture intolerance, sialadenitis, increased dental caries and periodontal disease. The aetiology may be a functional disturbance or a morphological disorder. A broad-based programme is indicated in its management and this includes either stimulating residual gland function with sialogogues or, in severe cases, replacing the saliva with a substitute. Currently, most saliva substitutes are based on an aqueous solution containing carboxymethylcellulose or animal mucin. Delivery of these solutions remains a major factor in the successful clinical management of severe salivary gland dysfunction. Rinses and sprays are the most commonly employed delivery systems, being more acceptable than pastilles or lozenges which require a reasonable amount of saliva already present in the mouth in order to dissolve. A number of designs for reservoirs in dentures have been constructed. These are intended to deliver a steady supply of the saliva substitute over an extended time, although these have not as yet been widely adopted.