Effect of stabilization splint therapy on pain during chewing in patients suffering from myofascial pain.

Masticatory myofascial pain (MFP) condition is a musculoskeletal disorder that compromises the functional capacities of the masticatory system. As such, the incorporation of an intensive chewing test as a discriminatory exercise for the diagnosis of this condition and evaluation of treatment success has considerable potential. Various splint designs have been used successfully, which have posed a question of whether the therapeutic effect of the splint is a placebo or has some other curative properties. The purpose of this study was to evaluate the efficacy of the stabilization appliance to reduce signs and symptoms in MFP patients and to compare the pain experience during the chewing test between two groups of patients, with and without splints. Myofascial pain patients (n = 37) who reported exacerbation of pain in function participated in the study. Patients perfomed a 9-min chewing test, followed by 9-min rest and marked their pain intensity on a visual analogue scale every 3 min. Of the 37 patients, 21 received a stabilization flat occlusal splint for night use and 16 were equally monitored clinically without a splint. At the end of 8 weeks, a second clinical examination and chewing test were performed. Student's t-test was used to analyse differences between study groups. Analysis of variance and covariance (ancova) with repeated measures was applied to analyse the effect of treatment. Level of pain at baseline prior to the chewing test (P0) was introduced as a co-variant. At baseline both groups showed relatively high scores of pain intensity and did not show any significant differences among the collected variables. At the end of the experiment, the splint group had a statistically significant reduction in pain intensity, in mean muscle sensitivity to palpation and in the pain experience during the chewing test compared with no change in the controls. A stabilization splint has a therapeutic value beyond its placebo effects. Thus, it should be an integral part of the treatment modalities in MFP disorder patients. An intensive chewing test is an effective tool to evaluate the treatment modality efficacy in MFP patients.

Oral habits among adolescent girls and their association with symptoms of temporomandibular disorders.

AIM: To evaluate the contribution of certain parafunctional activities to the presence of temporomandibular disorder (TMD) symptoms among teenage girls, with special emphasis to gum chewing and jaw play. METHODS: A total of 323 girls, aged 15-16 years, were randomly selected from a religious junior high school. The girls responded to a questionnaire on oral habits and TMD symptoms. RESULTS: Gum chewing was a very prevalent habit (62.4%), performed daily (mean chewing time 3.95 h day-1). Girls who chewed intensively (more than 4 h day-1) showed associations with pain in the ear area during function and at rest, as well as with joint noises. Jaw play, although reported by only 14.3%, was significantly associated with pain in the ear area during function and at rest, feeling of tiredness of the jaw while chewing, joint noises, catch and lock. All oral parafunctions, except chewing gum, were associated with jaw play and with each other. CONCLUSIONS: Jaw play was the most detrimental habit in TMD; intensive gum chewing was a potentially contributing factor for joint noises and pain. Oral parafunctions (except chewing gum) were significantly associated between themselves and suggest a behavioural pattern of "jaw hyperactivity".

Oral motor parafunctions among heavy drug addicts and their effects on signs and symptoms of temporomandibular disorders.

AIMS: To investigate the prevalence of temporomandibular disorders (TMD), bruxism, and other oral habits among drug addicts compared to a normal, non-addicted, matched control population, and to assess the detrimental effect of long-term drug abuse on the parameters studied. METHODS: Subjects included 55 drug-addicted patients (51 males and 4 females) randomly selected from long-term addicts using "hard" narcotics and attending a methadone maintenance center and a control group of 52 normal non-addicted individuals (48 males and 4 females) matched to the addicts for age, gender, and socioeconomic status. A clinical examination and a questionnaire were used. One examiner determined that all questions were correctly understood and answered, and a second examiner performed the clinical examinations and was unaware of the results of the questionnaire. RESULTS: The addicted group had a high prevalence of orofacial motor behavior (bruxing, clenching) as well as signs and symptoms of TMD (morning headache, joint noises, joint and masticatory muscle tenderness to palpation, and tooth wear) compared to the controls. Active (voluntary) jaw opening was significantly smaller, although within an acceptable range when compared to the controls. CONCLUSION: Long-term drug abuse detrimentally affects the stomatognathic system, as expressed in a high prevalence of oral motor behavior and signs and symptoms of TMD.

Splints and stress transmission to teeth: an in vitro experiment.

OBJECTIVE: To determine the influence of hard and soft splints with two thicknesses on the stress transmission to the tooth supporting the splint and the opposite tooth. METHODS: Continuous vertical forces up to 500N were applied to two opposite first molar phantom teeth using a universal loading machine. Deformation was detected by strain gauges attached to the cervical area of the buccal and lingual aspects of the lower tooth. Strain, as a function of force, was collected and the slope, defined as the compliance (in microS/N) of the system, was calculated. RESULTS: The highest compliance was found with hard splints. When splints were constructed on the upper molar, the highest compressive compliance was registered on the buccal side (2.8 microS/N) and tension compliance on the lingual side (-0.35 microS/N). When constructed on the lower tooth, the opposite was found. Soft splints resulted in compression on both the buccal and lingual sides when adjusted to the upper or lower tooth. A higher compliance was found on the buccal side (1.26 microS/N), while on the lingual side, the values varied (0.48-0.78 microS/N). CONCLUSIONS: Soft splints are more efficient in protecting teeth against the damage of bending forces although there is an increase of compression forces. The tooth opposing a hard splint is exposed to a higher risk of bending forces.

Generalized joint laxity and its relation with oral habits and temporomandibular disorders in adolescent girls.

A group of 248 girls, aged 15-16 years, were randomly selected and examined both clinically and by questionnaire with regard to the signs and symptoms of temporomandibular disorders (TMD), generalized joint laxity (GJL), range of mandibular opening, temporomandibular joint (TMJ) hypermobility and presence of oral parafunctions. The prevalence of GJL was 43% and that of TMJ hypermobility (TMJH) was 27.3%. A significant, albeit weak, correlation was found between the two. In the presence of joint click, both active and passive opening were significantly larger. When either muscle or joint sensitivity to palpation was present, the difference between the active and passive range of mouth opening increased significantly. The presence of reported clicks was negatively associated with GJL. This association was not valid in the presence of parafunction. Some of the signs and symptoms of TMD affected the range of mouth opening. In the presence of joint clicks, the mean active and passive mandibular opening were significantly larger. In the presence of joint and muscle sensitivity to palpation, the difference between passive and active mouth opening was larger. This was possibly because of the effect of pain on the full active range of opening, which was invalid in the registration of the passive mandibular opening. GJL, when present, did not seem to jeopardize the health of the stomatognathic system as expressed in the signs and symptoms of TMD. There was a negative association between GJL and the presence of reported joint clicks and catch. When a parafunction was present in addition to GJL, this association was invalid but not reversed, as has been previously reported.

Oral habits and their association with signs and symptoms of temporomandibular disorders in adolescent girls.

A group of 248 randomly selected high school girls, aged 15-16 years, completed a questionnaire and were examined clinically with regard to various oral habits and signs and symptoms of temporomandibular disorders (TMD). Common habits reported in the literature, such as gum chewing, nail biting, biting foreign objects, clenching and bruxism, eating seeds and crushing ice, as well as two less reported habits, 'jaw play' and continuous arm leaning, were evaluated. The most outstanding finding was the high prevalence and intensity of gum chewing among our study group: 92% of the girls chewed daily and 48% chewed gum for more than 3 h a day (intensive gum chewing). Statistically significant associations were found between intensive gum chewing and muscle sensitivity (P<0.001) and joint noises (P<0. 05), and between crushing ice and muscle sensitivity to palpation (P<0.005). A positive association was found between 'jaw play' and joint disturbances: reported joint noises (P<0.01), catching of the joint (P<0.01) and joint tension (P<0.001). A positive association was also found between arm leaning and reported joint noises (P<0. 05), catching (P<0.05), and joint tension (P<0.005). There was no association between the presence of bruxism and muscle sensitivity to palpation or joint disturbances. The potential harmful effects of intensive gum chewing, 'jaw play', continuous arm leaning and ice crushing are presented in this study. In light of these findings, the professional community should address these habits with proper data gathering, examination and consultation.

Topical application of capsaicin for the treatment of localized pain in the temporomandibular joint area.

AIMS: To determine the effectiveness of topical capsaicin cream application on localized pain in the temporomandibular joint (TMJ) area. METHODS: A randomized, double-blind, placebo-controlled study was conducted on 30 patients suffering from unilateral pain in the TMJ area. Patients were randomly divided into experimental and placebo groups; they were instructed to apply 0.025% capsaicin cream or its vehicle to the painful TMJ area 4 times daily for 4 weeks. Subjective parameters of present pain, most severe pain, effect of pain on daily activities, and pain relief were assessed each week on a visual analog scale. Muscle and joint sensitivity to palpation on the painful and contralateral joints and maximal mouth opening (assisted/passive and non-assisted/active) were examined weekly by the same experienced examiner. RESULTS: Capsaicin cream produced no statistically significant influence on measured variables when compared to placebo. Both experimental and placebo groups showed statistically significant improvement in most variables during the experiment. CONCLUSION: The factor of time had a major effect in the non-specific improvement of the parameters assessed. The placebo effect played an important role in the treatment of patients with pain in the TMJ area.