Pharmacological treatment of oro-facial pain - health technology assessment including a systematic review with network meta-analysis

Oral health-related quality of life (OHRQoL) is considered an important aspect of different oral conditions. It has also gained increased attention in temporomandibular disorders (TMDs) in recent years. The purpose of this study was to systematically review the literature on OHRQoL and TMDs. A systematic search of the dental literature was performed using the Medline and Cochrane Library databases, supplemented by a hand search. Various combinations of search terms related to OHRQoL and TMDs were used. Among numerous titles found in Medline, abstracts and eventually full papers of potential interest were reviewed. Twelve papers fulfilled the inclusion criteria and were included in the review. Most studies used the Oral Health Impact Profile, an instrument with good psychometric properties, for evaluation. All articles described a substantial impact on OHRQoL in TMD patients. Only a small proportion of all patients, a few percent, reported no impact at all. The difference between men and women was small and not significant. The impact appeared to be more pronounced in patients with more signs and symptoms. The perceived impact of pain on OHRQoL seems to be substantial. Two studies found that the impact increased with age among TMD patients. The reviewed studies convincingly demonstrated that OHRQoL was negatively affected among TMD patients.

This systematic review (SR) synthesises recent evidence and assesses the methodological quality of published SRs in the management of temporomandibular disorders (TMD). A systematic literature search was conducted in the PubMed, Cochrane Library, and Bandolier databases for 1987 to September 2009. Two investigators evaluated the methodological quality of each identified SR using two measurement tools: the assessment of multiple systematic reviews (AMSTAR) and level of research design scoring. Thirty-eight SRs met inclusion criteria and 30 were analysed: 23 qualitative SRs and seven meta-analyses. Ten SRs were related to occlusal appliances, occlusal adjustment or bruxism; eight to physical therapy; seven to pharmacologic treatment; four to TMJ and maxillofacial surgery; and six to behavioural therapy and multimodal treatment. The median AMSTAR score was 6 (range 2-11). Eighteen of the SRs were based on randomised clinical trials (RCTs), three were based on case-control studies, and nine were a mix of RCTs and case series. Most SRs had pain and clinical measures as primary outcome variables, while few SRs reported psychological status, daily activities, or quality of life. There is some evidence that the following can be effective in alleviating TMD pain: occlusal appliances, acupuncture, behavioural therapy, jaw exercises, postural training, and some pharmacological treatments. Evidence for the effect of electrophysical modalities and surgery is insufficient, and occlusal adjustment seems to have no effect. One limitation of most of the reviewed SRs was that the considerable variation in methodology between the primary studies made definitive conclusions impossible.

Burning mouth syndrome is a common disorder that frequently affects women in the 5th-7th decade. It is characterized by persisting painful symptoms mainly involving the anterior two-thirds of the tongue. For several years it has been attributed to psychological causes. We investigated the innervation of the epithelium of the tongue to assess whether damage of peripheral nerve fibers underlies the pathogenesis of the disease. We examined 12 patients with clinically definite burning mouth syndrome for at least 6 months. We obtained superficial biopsies of the lateral aspect of the anterior two-thirds of the tongue from all patients and nine healthy controls. Immunohistochemical and confocal microscope co-localization studies were performed with cytoplasmatic, cytoskeletric, Schwann cell, and myelin markers for pathological changes. The density of epithelial nerve fibers was quantified. Patients showed a significantly lower density of epithelial nerve fibers than controls, with a trend toward correlation with the duration of symptoms. Epithelial and sub-papillary nerve fibers showed diffuse morphological changes reflecting axonal degeneration. Our study demonstrates that burning mouth syndrome is caused by a trigeminal small-fiber sensory neuropathy and that superficial biopsy of the tongue can be helpful in assessing the diagnosis. These findings shed light into the pathogenesis of this common disorder and could contribute to evaluate targeted therapies in patients.