Plunging or cervical ranula. Review of the literature and report of 4 cases.

A review of the literature pertaining to plunging ranula is presented with special emphasis on the historical development of the various aetiological theories and treatment recommendations. Also 4 cases of plunging ranula are presented; three were treated by extirpation of the sublingual gland and one was treated by exteriorization of the ranula into the oral cavity. The treatment methods used here are discussed in relationship to the accepted aetiological theory.     

Cholinergic nerves of unknown origin in the parotid glands of rats.

The effectiveness of the parasympathetic denervation of the gland caused by avulsion of the auriculo-temporal nerve was investigated. In the first type of experiment, the cholinesterase inhibitor, eserine, was injected through the salivary duct. The substance is thought to preserve acetylcholine leaking from nerve endings, thereby causing secretion of saliva; a secretory response was thus taken as evidence for the presence of cholinergic nerves. In the second type of experiment, the acetylcholinesterase activity of the gland was examined histochemically. From the denervated glands, eserine caused secretion and acetylcholinesterase positive nerves were found in the glands. Both the amount of secretion and the number of nerves were greatly diminished when compared with the intact glands. The results indicate that the denervation procedure was incomplete, leaving some cholinergic nerves unsevered. That cholinergic nerves remain offers an explanation to the residual choline acetyltransferase activity, which has earlier been shown in the gland after avulsion of the auriculo-temporal nerve. To extend the denervation procedure, either avulsion of the facial nerve or avulsion of the superior cervical ganglion was included. Neither procedure abolished the response to eserine or the acetyl-cholinesterase activity, indicating that the routes for the remaining nerves are to be found elsewhere.     

The effect of the bite plane splint on the electromyographic silent period duration

An electromyographic study of the masseter and anterior part of the temporalis muscles was performed on ten patients presenting temporomandibular joint dysfunction symptoms. The EMG silent periods (SP) produced in the open-close-clench cycle and jaw-jerk reflex were compared for duration before and after treatment with an occlusal bite splint. Following use of the splint, there was a shortening of SP indicating the possible use of the duration of SP as a diagnostic measurement, and also as an indication of treatment effectiveness.     

Incidence of oral lesions in HIV-1-infected women: reduction with HAART

Few studies assess the effectiveness of HAART on reducing the incidence and recurrence of oral lesions. We investigated such changes among 503 HIV+ women over six years in the Women's Interagency HIV Study. The incidence of erythematous candidiasis (EC), pseudomembranous candidiasis (PC), hairy leukoplakia (HL), and warts was computed over follow-up visits after HAART initiation compared with before HAART initiation. Analysis of our data demonstrates a strong decrease in candidiasis after HAART initiation. The incidence of EC fell to 2.99% from 5.48% (RR 0.545); PC fell to 2.85% from 6.70% (RR 0.425); and EC or PC fell to 3.43% from 7.35% (RR 0.466). No changes were seen in HL or warts. Higher HIV-RNA was associated with greater incidence of candidiasis and HL, but not warts. Analysis of these data indicates that recurrence and incidence of candidiasis are reduced by HAART, and that recurrence is reduced independently of CD4 and HIV-RNA.     

Mental stress-induced physiological changes in the human masseter muscle

The effect of a long mental stress on the hemodynamics of masticatory muscles has not been investigated to date. We hypothesized some hemodynamic and electromyographic changes in jaw-closure muscles related to sympathetic nervous system activity. While healthy adult female volunteers performed a two-hour mental stress task, electromyographic activity of the temporal and masseteric muscles was recorded, and hemodynamic changes of the masseter muscle were measured non-invasively. Autonomic function was assessed by heart rate spectral analysis. Integrated electromyographic activity of the temporalis muscle, but not the masseter muscle, showed an increase that coincided with the increase in sympathetic nervous activity. In the masseter muscle, despite little change in integrated electromyographic activity, notable changes were found in hemodynamic parameters. These results suggest that hemodynamics of jaw muscles is susceptible to mental stress, implying a potential role in the etiology of jaw muscle dysfunction associated with mental stress.