The etiology of superficial oral mucoceles.

To the Editor:—For those of us with a long-term interest in benign salivary gland disease, Dr Mandel has presented an unusual and very interesting case report, “Multiple Superficial Oral Mucoceles,” in the August issue of the Journal (J Oral Maxillofac Surg 59:928, 2001). He states that “the etiology of the multiple superficial mucocele is not known.” I would like to propose a cause for these lesions. Dr Mandel clearly describes the development of the vast majority of mucoceles of the minor of accessory salivary glands as an extravasation or leakage of mucus into the surrounding submucosal tissue after trauma to the salivary duct. However, there is a cause other than physical trauma for mucocele development that is confined, in most cases, to the midportion of the junction of the hard and soft palate and almost the entire soft palate. This is the so-called retention (cyst) phenomenon, which arises as a result of narrowing of the duct openings after chronic, low-grade surface irritation. This produces ductal dilation and visible surface swelling. These lesions are significantly smaller than the extravasation mucoceles, developing from the other accessory salivary glands. One needs only examine the excisonal biopsy specimen presented to note that the cavity is entirely intraepithelial rather than submucosal and there is a dilated duct immediately inferior to the lesion. This is exactly what you might expect to find with the retention-type mucocele. We see this effect at times in patients with nicotine stomatitis in whom the heat or noxious tobacco products result in local surface irritation. Are there any other possible causes for mucosal irritation? The author made reference to a case report suggesting tartar control toothpaste as a possible cause. We are also aware of patients who indulge in frequent mouthwashing with hydrogen peroxide, deodorant mouthwashes, antiplaque solutions, and, the most popular, Listerine, which are clearly irritative. All of these contain significant concentrations of alcohol which, over a period of time, can affect the mucosal surface. I wonder whether the author specifically inquired about such habits or any other habits that might have a similar irritating affect when taking the medical history?