Journal of Oral & Facial Pain and Headache, 01/2008

Aims: To systematically compare clinical findings and psychosocial factors between patients suffering from atypical odontalgia (AO) and an age- and gender-matched group of patients with temporomandibular disorders (TMD). Methods: Forty-six AO patients (7 men and 39 women; mean age, 56 years) were compared with 41 TMD patients (8 men and 33 women; mean age, 58 years). Results: Mean pain intensity at the time of inclusion in the study was similar between the groups (TMD: 5.3 ± 0.4, AO: 5.0 ± 0.3), but pain duration was longer in AO patients (AO: 7.7 ± 1.1 years, TMD: 4.5 ± 0.1 years). Eighty-three percent of the AO patients and 15% of TMD patients reported pain onset in relation to dental/surgical procedures. Episodic tension-type headache (TTH) occurred equally in both groups (TMD: 46%, AO: 46%), but TMD patients more frequently experienced chronic TTH (TMD: 35%, AO: 18%), myofascial TMD (TMD: 93%, AO: 50%), and temporomandibular joint disorders (TMD: 66%, AO: 2%). Overall, TMD patients had lower pressure pain thresholds and poorer jaw function than AO patients. Mean depression and somatization scores were moderate to severe in both groups, and widespread pain was most common in TMD patients. Conclusion: AO and TMD share some characteristics but differ significantly in report of dental trauma, jaw function, pain duration, and pain site. Keywords: neuropathic pain, orofacial pain, pain characteristics, psychosocial status, quality of life

Aims: To determine the effects of experimental jaw-muscle pain on jaw movements. Methods: Mandibular mid-incisor point was tracked in 22 asymptomatic subjects during standardized (at 2.2 mm/s) protrusion, contralateral excursion, and open jaw movements, as well as free, right-sided chewing and chewing standardized for timing (900 ms/cycle). Tonic infusion of 4.5% hypertonic saline into the right masseter muscle maintained pain intensity between 30 and 60 mm on a 100-mm visual analog scale. Subjects performed tasks in 3 sessions on the same experimental day: control condition (baseline trials), test condition 1 (during hypertonic or 0.9% isotonic saline infusion), and test condition 2 (during isotonic or hypertonic saline infusion). Results: In comparison with control, there were no significant effects of hypertonic saline infusion on amplitude or velocity for protrusion or contralateral jaw movements or on velocity for jaw opening. Jaw-opening amplitude was significantly smaller in comparison with control during hypertonic, but not isotonic, saline infusion. During free but not standardized chewing, subjects chewed faster and exhibited larger amplitude gapes during hypertonic and isotonic infusion in comparison with control. Therefore, it was unlikely that pain had an effect on the kinematic parameters of jaw movement during free chewing. Qualitatively, individual subject data revealed considerable variability in the effects of hypertonic saline on movement parameters, which suggests that the effect of pain on jaw movement may not be uniform between individuals. Conclusions: The data indicate that the effect of pain on jaw movement may vary with the task performed. Keywords: chewing, experimental pain, hypertonic saline, jaw movement, Pain Adaptation Model

Aims: To test a measurement model based on clinicians' assessments of patient data that allows simple and confident clinical validation of any statistical or numerical technique designed to separate patients improving with treatment from those who are not, particularly for pain that shows large daily variation. Methods: Diaries using daily visual analog scales (VAS) of pain intensity were obtained from 39 patients treated for chronic temporomandibular disorders. Three experienced clinicians visually assessed 39 VAS/time graphs. Criteria indicating improvement (general trend, height and apparent frequency of graph spikes) evolved over 3 assessments. The third assessment defined improvers visually. Numeric analyses considered the difference between first and last months of treatment for mean, area under the curve (AUC), and maximum VAS scores. Thresholds of 40%, 50%, or 60% pain reduction defined improvement numerically. Aggregate sensitivity and specificity was compared with visual definition to find the optimal threshold. Results: Patients were defined visually as improvers, nonimprovers, and borderline cases. Interexaminer reliability for identifying improvers was good (k = 0.79). Mean VAS and AUC were highly correlated (r = 0.999). The optimal threshold of mean and maximum VAS relative to visual definition was 50% pain reduction. Cases defined as improvers by both mean and maximum agreed best with the visual definition (sensitivity 90%, specificity 84%). Conclusion: Visual assessment of VAS demonstrates distinct pain/time patterns that can validate numeric definition of complex pain recovery. No single numeric method can be guaranteed to give a clinically valid outcome. Keywords: chronic pain, pain diaries, pain measurement, stabilization splint, temporomandibular disorders, treatment outcomes, visual analog scales

Aims: To determine whether symptoms of post-traumatic stress disorder (PTSD) are related to the pain of temporomandibular disorders (TMD) in a community-based sample of female twin pairs, and if so, to ascertain whether the association is due to the presence of chronic widespread pain (CWP) and familial/genetic factors. Methods: Data were obtained from 630 monozygotic and 239 dizygotic female twin pairs participating in the University of Washington Twin Registry. PTSD symptoms were assessed with the Impact of Events Scale (IES), with scores partitioned into terciles. TMD pain was assessed with a question about persistent or recurrent pain in the face, jaw, temple; in front of the ear; or in the ear during the past 3 months. CWP was defined as pain located in 3 body regions during the past 3 months. Random-effects regression models, adjusted for demographic features, depression, CWP, and familial/genetic factors, were used to examine the relationship between the IES and TMD pain. Results: IES scores were significantly associated with TMD pain (P < .01). Twins in the highest IES tercile were almost 3 times more likely than those in the lowest tercile to report TMD pain, even after controlling for demographic factors, depression, and CWP. After adjustment for familial and genetic factors, the association of IES scores with TMD pain remained significant in dizygotic twins (Ptrend = .03) but was not significant in monozygotic twins (Ptrend = .30). Conclusion: PTSD symptoms are strongly linked to TMD pain. This association could be partially explained by genetic vulnerability to both conditions but is not related to the presence of CWP. Future research is needed to understand the temporal association of PTSD and TMD pain and the genetic and physiological underpinnings of this relationship. Keywords: chronic widespread pain, genetic factors, post-traumatic stress disorder, temporomandibular disorder, twins

Aims: To determine the association between temporomandibular disorders (TMD) and experiences of jaw injury, third molar removal, and orthodontic treatment, controlling for confounding factors such as age, sex, emotional stress, and oral parafunction. Methods: First-year university students (n = 2,374) were instructed to answer a questionnaire regarding symptoms of TMD, jaw injury, third molar removal, orthodontic treatment, stress, and parafunctional habits. All subjects were classified according to the level of TMD symptoms. Logistic regression was applied to assess the associations of experiences of jaw injury, third molar removal, and orthodontic treatment with presence of TMD symptoms after controlling for age, sex, stress, and parafunctional habits. Results: Of the 2,374 students, 715 students were TMD symptom-positive. They were classified into 7 groups consisting of those with only clicking (group 1), only pain in the temporomandibular joint (group 2), only difficulty in mouth opening (group 3), clicking and pain (group 4), clicking and difficulty in mouth opening (group 5), difficulty in mouth opening and pain (group 6), and all 3 symptoms (group 7). TMD symptoms were significantly associated with jaw injury. Odds ratios were 2.25, 2.47, 3.38, and 2.01 for groups 2, 3, 6, and 7, respectively. Experience of third molar removal was significantly associated with TMD (odds ratio = 1.81 for group 1). No association was found between orthodontic experience and TMD. Conclusion: Experiences of jaw injury and third molar removal might be cumulative and precipitating events in TMD. Keywords: jaw injury, orthodontic treatment, third molar removal, university students

Aims: To describe 1 year's experience in treating orofacial pain with intramuscular injections of 0.5% bupivacaine bilateral to the spinous processes of the lower cervical vertebrae. Methods: A retrospective review of 2,517 emergency department patients with discharge diagnoses of a variety of orofacial pain conditions and 771 patients who were coded as having had an anesthetic injection between June 30, 2003 and July 1, 2004 was performed. The records of all adult patients who had undergone paraspinous intramuscular injection with bupivacaine for the treatment of an orofacial pain condition were extracted from these 2 databases and included in this retrospective review. Pain relief was reported in 2 different ways: (1) patients (n = 114) were placed in 1 of 4 orofacial pain relief categories based on common clinical experience and face validity and (2) pain relief was calculated based on patients' (n = 71) ratings of their pain on a numerical descriptor scale before and after treatment. Results: Lower cervical paraspinous intramuscular injections with bupivacaine were performed in 118 adult patients. Four charts were excluded from review because of missing or inadequate documentation. Pain relief (complete or clinical) occurred in 75 patients (66%), and partial orofacial pain relief in 32 patients (28%). No significant relief was reported in 7 patients (6%). Overall, some therapeutic response was reported in 107 of 114 patients (94%). Orofacial pain relief was rapid, with many patients reporting complete relief within 5 to 15 minutes. Conclusion: This is the first report of a large case series of emergency department patients whose orofacial pain conditions were treated with intramuscular injections of bupivacaine in the paraspinous muscles of the lower neck. The findings suggest that lower cervical paraspinous intramuscular injections with bupivacaine may prove to be a new therapeutic option for acute orofacial pain in the emergency department setting. Keywords: allodynia, bupivacaine, cervical, headache, injection, intramuscular, orofacial, pain, paraspinous, trigeminocervical

Pain and dysfunction in the temporomandibular joint (TMJ) region represent a diagnostic challenge. Temporomandibular disorders (TMD) are usually diagnosed by means of a thorough patient history and comprehensive clinical examination. However, additional diagnostic tests, such as imaging of the TMJ area, are necessary in cases where the signs do not explain the symptoms. Neoplasms and pseudotumors of the TMJ are quite uncommon, but their early recognition is necessary in order prevent the delay of correct treatment. This report describes 3 cases of different intraosseous lesions of the mandibular condyle in which the patient was erroneously first treated for a TMD. Keywords: cyst, differential diagnosis, mandibular condyle, neoplasm, temporomandibular disorders, temporomandibular joint

Nasopharyngeal cancer can occur in any age group and is often misdiagnosed. Cervicogenic headache (CEH) is a clinical condition, putatively originating from nociceptive structures in the neck. A patient with CEH-like symptoms occurring as a result of nasopharyngeal cancer invasion is reported. A 77-year-old man was admitted to the anesthesiology department (pain unit) with a 3-month history of severe unilateral headache. The headache began in the right part of the neck and spread to the right fronto-orbital region and was always unilateral. There was no history of neck trauma, and the headache did not increase with neck movement. Analgesics were ineffective. The visual analog scale score for pain was 6. Neurological examination demonstrated tenderness over the right greater occipital nerve and reduced range of motion in the cervical spine. Cervical computerized tomography revealed a solid tumor in the right parapharyngeal region, adjacent to the C2-C3 vertebrae. To the authors' knowledge, this is the first case in the literature of tumoral invasion of nasopharyngeal cancer presenting as CEH. Cervical neuroimaging is obligatory in patients with late-onset, severe CEH. Keywords: cervical neuroimaging, cervicogenic headache, elderly, headache, parapharyngeal tumor

TMD and Orthodontics Consensus Conference XX Italian Society of Orthodontics (SIDO) International Congress October 27, 2007 Mostra d'Oltremare, Naples, Italy