[Diagnosing neuropathic orofacial pain in the general dental practice]. / Diagnosticeren van neuropathische orofaciale pijn in de algemene tandartspraktijk.

Dental pain is a common reason for patients to visit the dentist. This type of pain is usually easy to diagnose and treat. However, diagnosing and treating other forms of orofacial pain remains complicated. One of the most challenging types of orofacial pain to diagnose and treat is neuropathic orofacial pain: pain resulting from damage to nerve tissue. Recognizing this type of pain in a timely manner can prevent unnecessary invasive dental treatments and disappointment for patients who seek help for this type of pain. There are relatively simple tools for dentists to distinguish neuropathic pain from other types of orofacial pain. The treatment of neuropathic pain is primarily focused on symptom relief through medication.

[Treatment of bruxism with botulinum toxin: think twice!] / Behandeling van bruxisme met botulinetoxine: bezint eer ge begint!

A recent publication in the Nederlands Tijdschrift Voor Tandheelkunde (Dutch Journal of Dentistry) suggests botulinum toxin as a primary treatment for bruxism, especially for severe complaints of teeth grinding or jaw clenching. However, in the opinion of Lobbezoo et al., some outdated views on bruxism are used, and botulinum toxin is incorrectly classified as safe, according to them. In this Vision article, the authors describe the current insights into bruxism; they indicate how the presence of bruxism can be assessed in the clinic; when and how bruxism is treated; and finally, what the role of botulinum toxin is: an ultimum refugium. Therefore, regarding the use of botulinum toxin within the discipline of orofacial pain and dysfunction Lobbezoo et al. recommend: think twice!

[Patient-specific joint prothesis for ankylotic temporomandibular joints]. / Individueel vervaardigde prothesen voor ankylotische kaakgewrichten.

A 49-year-old woman who suffered from severe obstructive sleep apnea (OSA) was referred to the department of Oral-, Maxillofacial Surgery department due to progressive limitation of the mouth opening and chronic pain in both temporomandibular joints. Based on clinical and radiological examinations, the patient was diagnosed with recurrent ankylosis of the temporomandibular joints. The patient was treated with 2 patient-specific implants of the temporomandibular joint combined with a Le Fort I osteotomy, and a genioplasty including a genioglossus advancement. This treatment may have advantages for the patient such as a lower recurrence rate of ankylosis, improved maximal mouth opening, pain reduction and improved aesthetic results.

Is dopaminergic medication dose associated with self-reported bruxism in Parkinson's disease? A cross-sectional, questionnaire-based study.

OBJECTIVES: It is not clear whether dopaminergic medication influences bruxism behaviour in patients with Parkinson's disease (PD). Therefore, the aims are to investigate (i) the prevalence of possible (i.e., self-reported) bruxism (sleep and awake) in PD patients, and (ii) whether the use of dopaminergic medication and other factors (viz., demographic characteristics, PD-related factors, and possible consequences of bruxism) are associated with possible bruxism (sleep or awake). MATERIALS AND METHODS: This study concerns a secondary analysis of an earlier published study. Three hundred ninety-five PD patients (67.9 ± 8.6 years of age; 58.7% males) were included. The levodopa equivalent daily dosage (LEDD) was used as a measure of the dopaminergic medication level. Subsequently, a logistic regression analysis was performed for the dependent variables 'awake bruxism' and 'sleep bruxism', with the following predictors: gender, age, LEDD, time since PD diagnosis, temporomandibular disorder (TMD) pain, jaw locks, and tooth wear. RESULTS: The prevalence of possible awake and sleep bruxism was 46.0% and 24.3%, respectively. Awake bruxism was associated with sleep bruxism (OR = 8.52; 95% CI 3.56-20.40), TMD pain (OR = 4.51; 95% CI 2.31-8.79), and tooth wear (OR = 1.87; 95% CI 1.02-3.43). Sleep bruxism was associated with tooth wear (OR = 12.49; 95% CI 4.97-31.38) and awake bruxism (OR = 9.48; 95% CI 4.24-21.19). Dopaminergic medication dose was not associated with awake bruxism (OR = 1.0; 95% CI 0.99-1.00) or sleep bruxism (OR = 1.0; 95% CI 0.99-1.00). CONCLUSION: Bruxism is a common condition in PD patients, but is not associated with the dopaminergic medication dose. CLINICAL RELEVANCE: (Oral) health care providers should be alerted about the possibility of sleep and awake bruxism activity in PD patients, along with this activity's possible negative health outcomes (viz., TMD pain, tooth wear).

[Orofacial pain: a discipline on the brink of a new era]. / Orofaciale pijn: een vakgebied aan de vooravond van een nieuw tijdperk.

The orofacial pain discipline is on the brink of a new era. The introduction of a new definition of pain that, unlike the previous definition, also applies to individuals who cannot verbally express their pain, as well as the publication of the new international classification for orofacial pain, will contribute significantly to the improvement of the quality of the diagnostic process, thus increasing the chance of a successful treatment. Ultimately, the orofacial pain patient will emerge as the winner. The purpose of this article is to introduce the reader to these important recent developments and to provide him/her with an understanding of the implications of these developments for orofacial pain diagnosis and treatment in general and specialized dental practice.

[Parkinson's disease, temporomandibular disorders and bruxism: A pilot study]. / De ziekte van Parkinson, temporomandibulaire disfunctie en bruxisme.

Even though bruxism and Parkinson's disease have much in common, a possible relationship between them has not been established. The aim of this study was to gain more insight into a possible relationship between bruxism and temporomandibular disorders on the one hand and Parkinson's disease on the other. For this study, 708 people (368 with Parkinson's disease or parkinsonism and 340 controls) fully completed a questionnaire. The questionnaire included a selective Dutch translation of the questions from the Diagnostic Criteria for TMD (DC/TMD), complemented with a question about tooth wear. The chi-square test and independent samples t test were used for the data analysis. The results showed patients with Parkinson's disease or parkinsonism reported pain resulting from temporomandibular disorders and bruxism when asleep and awake significantly more often than the controls. When facial pain was reported, patients with Parkinson's disease or parkinsonism had a higher mean pain score than the controls. In conclusion, this study showed a relationship between Parkinson's disease or parkinsonism on the one hand and bruxism on the other. Furthermore, the study revealed a relationship between Parkinson's disease or parkinsonism on the one hand and pain resulting from temporomandibular disorders on the other.

Two repetitive bouts of intense eccentric-concentric jaw exercises reduce experimental muscle pain in healthy subjects.

High-intensity eccentric-concentric contractions of the jaw-closing muscles induce muscle soreness, fatigue and functional impairment of the jaw, resembling the symptoms of myalgia, according to the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD). However, it is claimed that repetition of similar exercises can minimise these detrimental effects. This study aimed to evaluate the response of jaw-closing muscles following two series of intense eccentric-concentric exercises of the masticatory muscles in healthy subjects. Twelve pain-free participants underwent 2 sessions of intense eccentric-concentric jaw exercises, with 1-week interval in between. Each session of jaw exercises comprises 6 sets of 5-minute-long bouts of concentric-eccentric contractions. Self-reported muscle fatigue and pain, maximum mouth opening without pain (MMO), pain pressure thresholds (PPTs) of temporalis and masseter muscles and maximum voluntary bite force (MVBF) were recorded before, immediately after, 24 and 48 hours after each bout of exercises. ANOVA for repeated measurements was used to analyse the data. During session 2, muscle pain and fatigue were statistically significantly decreased (P < .05) as compared to session 1. Furthermore, statistically significant increases of MVBF (P < .005), MMO (P < .005) and PPTs (P < .005) were found at session 2 as compared to session 1. Within the limitations of the study, is can be concluded that the repetition of eccentric-concentric jaw-closing exercises results in signs of muscle training. Future studies can elucidate whether this motor training might be useful for the treatment of myalgia.

Long-term variability of sleep bruxism and psychological stress in patients with jaw-muscle pain: Report of two longitudinal clinical cases.

Sleep bruxism (SB) and psychological stress are commonly considered as contributing factors in the aetiology of temporomandibular disorder (TMD) pain. However, the lack of longitudinal studies and fluctuating nature of SB, psychological stress and TMD pain have led to contradictory results regarding the association between the possible aetiological factors and TMD pain. In the present study we investigated the contribution of SB and psychological stress to TMD pain in a longitudinal study of 2 clinical TMD pain cases during a 6-week study protocol. Two female volunteers with clinically diagnosed myalgia based on the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) participated in the study. Questionnaires were used to record jaw-muscle pain and psychological stress experience, and an ambulatory polysomnography technique was used to record SB intensity. Visual analysis of the data revealed that the intensity of TMD pain was not hardwired, neither with psychological stress experience nor with increased SB activity. Within the limitations of single-patient clinical cases design, our study suggested that the presence of TMD pain cannot be explained by a simple linear model which takes psychological stress or SB into account. It also seems that psychological stress was a more important predictor factor for TMD pain than SB.

Delayed-onset muscle soreness in human masticatory muscles increases inhibitory jaw reflex responses.

The effects of masticatory muscles' overloading on jaw-motor control are not yet fully clarified. Therefore, it was tested whether eccentric and concentric exercises of the human masticatory muscles would influence inhibitory jaw reflex responses. Eleven participants (6 males, 5 females) performed 6, 5-minutes bouts of eccentric-concentric contractions. Before, immediately after, 24 hours, 48 hours and 1 week afterwards, visual analogue scale (VAS) scores for jaw muscle fatigue and pain, maximum voluntary bite force (MVBF) and inhibitory jaw reflexes were recorded. Reflex data were analysed with the cumulative sum control chart error box method. Immediate and delayed masticatory muscle fatigue and pain were provoked. Further, 24 hours after the exercises, MVBF tended to decrease (P = .056), suggesting that delayed-onset muscle soreness (DOMS) was provoked in the masticatory muscles. In addition, the inhibitory jaw reflex showed a delayed increase in size 24 hours after the exercise (P < .05). In conclusion, DOMS provoked in the masticatory muscles alters jaw motor control by inducing a delayed increase in the size of the inhibitory jaw reflex.

Delayed-onset muscle soreness does not influence occlusal sensitivity and position sense of the mandible.

Masticatory muscle-pain patients often complain about sensorimotor changes, but the effects of pain on the psychophysical properties remain unclear. This study aimed to investigate the effects of delayed-onset muscle soreness (DOMS) on the jaw's position sense (PS) and occlusal sensitivity (OS). In all, 12 participants underwent intense concentric-eccentric jaw exercises. Self-reported muscle fatigue and pain, pain-free maximum mouth opening (MMO), pain pressure thresholds (PPTs) at right and left masseter and right and left anterior temporalis, maximum voluntary bite force (MVBF), PS and OS were recorded before, immediately after, 24 h, 48 h and 1 week after the exercises. Data were analysed with repeated measures anova. Pain and fatigue increased significantly after the exercises, while fatigue also increased 24 h afterwards. Time and site had a significant effect for PPTs, not for MVBF. MMO decreased significantly 24 h after the exercises. OS and PS did not change significantly. Experimentally induced DOMS does not influence the psychophysical properties of the masticatory system.

Assessment of the amount of tooth wear on dental casts and intra-oral photographs.

Tooth wear is a multifactorial condition, leading to the loss of dental hard tissues. Many grading scales are available to assess the amount of tooth wear, one of which is the tooth wear evaluation system (TWES). A grading scale can be used chairside, on casts and on photographs. The aim was to test whether the grading scales of the TWES, used on casts and on photographs, resulted in comparable scores. In addition, it was tested whether these scales can be used to assess tooth wear reliably on photographs. Of 75 tooth wear patients, sets of casts and series of photographs were obtained and graded. Comparison of the grading on casts and on photographs revealed equal median values and percentiles for both occlusal/incisal grading and non-occlusal/non-incisal grading. The grading on casts and on photographs showed a high correlation for the occlusal/incisal grading and a low correlation for the non-occlusal/non-incisal grading (Spearman's rho = 0·74 and rho = 0·47; P < 0·001). Concerning the grading on photographs, the interexaminer reliability was fair-to-good (ICC = 0·41 to ICC = 0·55) while the intra-examiner reliability was fair-to-good to excellent (ICC = 0·68 to ICC = 0·86) for the occlusal/incisal grading. For the non-occlusal/non-incisal grading, the interexaminer reliability was poor to fair-to-good (ICC = 0·22 to ICC = 0·59), while the intra-examiner reliability was fair-to-good to excellent (ICC = 0·64 to ICC = 0·82). It was concluded that the scores obtained with the grading scales of the TWES on casts and on photographs are comparable. The grading scales can be used in a reliable way on photographs, which is especially the case for occlusal/incisal grading.

[Painful temporomandibular dysfunctions: diagnosis and -treatment]. / Pijnlijke temporomandibulaire disfuncties: diagnose en behandeling.

Painful temporomandibular disorders (TMD pain) are common among the general population. The most common sub diagnoses are myalgia (jaw-muscle pain) and arthralgia (temporomandibular joint pain). The aetiology of TMD pain has a multifactorial nature, and its diagnosis and possible treatment often require a multidisciplinary approach. The most recent insights in the diagnosis and treatment of TMD pain are based on the multidisciplinary guideline 'Chronic Orofacial Pain' that was developed by the Dutch Society of Headache Patients and was published in 2013. Dentists are required to follow the recommendations of this guideline. The authorisation of the guideline by the relevant academic and professional associations in the Netherlands implies that restraint is advised when adopting diagnostic procedures and treatment modalities that are not or are insufficiently based on solid evidence.

Psychometric properties of the Dutch version of the Orofacial Esthetic Scale (OES-NL) in dental patients with and without self-reported tooth wear.

The aim of this study was to test the psychometric properties of the Dutch version of the Orofacial Esthetic Scale (OES) in dental patients with and without self-reported tooth wear. The English version of the OES was translated into Dutch, following established guidelines for cross-cultural adaptation of health-related quality of life measures. The reliability of the resulting OES-NL was tested in a test-retest study on 343 subjects; its validity was tested with the use of convergent validity on 582 subjects. The test-retest reliability of the OES-NL showed intra-class correlation coefficients (ICC) that ranged from 0·76 to 0·82, which can be qualified as excellent. The Cronbach's alpha revealed that the overall internal consistency of the scale was good (α = 0·89). Convergent validity was confirmed by the association between the OES-NL summary scores and three questions of the Dutch version of the Oral Health Impact Profile (OHIP-NL). The calculated Spearman's rank correlation coefficients ranged from -0·43 to -0·54 and were all significant (P < 0·001). The Dutch version of the Orofacial Esthetic Scale (OES-NL) showed good psychometric properties, making it suitable for the assessment of self-perceived aesthetics in Dutch dental patients with and without self-reported tooth wear.

Assessment of the progression of tooth wear on dental casts.

Many methods are available for the grading of tooth wear, but their ability to assess the progression of wear over time has not been studied frequently. The aim was to assess whether the occlusal/incisal grading scale of the Tooth Wear Evaluation System (TWES) was sensitive enough for the detection of tooth wear progression from 14 to 23 years of age. A total of 120 sets of dental casts were gathered from 40 people, of whom impressions were made at 14, 18 and 23 years. The TWES was used to assess loss of clinical crown height throughout the entire dentition. There was a significant difference in the TWES scores between the three age groups on all teeth (Friedman tests; P < 0.005 in all cases). Post hoc Wilcoxon tests revealed that the difference between the scores between 14 and 18 years and between 18 and 23 was significant for most teeth. It was concluded that the TWES is sensitive enough to detect changes in tooth wear over time.

[Persistent dento-alveolar pain disorder (PDAP)]. / Persisterende dentoalveolaire pijn (PDAP).

Dento-alveolar pain is common in the orofacial area. Persistent dento-alveolar pain could be experienced without an identifiable etiology with poor response to existing treatments. Confusion about the diagnosis and classification of persistent dento-alveolar pain (PDAP) disorders could explain the difficulties in treatment and unfavorable prognosis. Recently, initial steps were made to improve the taxonomy and diagnostic criteria for PDAP in order to improve clinical research and care.

The Global Need for Easy and Valid Assessment Tools for Orofacial Pain.

The World Health Organization recently adopted a historic resolution (WHA74.5) on the urgent need for global oral health improvement. This resolution is particularly relevant in the perspective of the high prevalence of untreated oral diseases. However, one important aspect has been mentioned only in passing, namely that poor oral health often leads to orofacial pain, which is the most common reason for emergency dental visits worldwide. Therefore, an evidence-based decision-making process on oral health should include data related to orofacial pain complaints. To that end, the availability of reliable and valid assessment tools of orofacial pain and related treatment outcomes is essential. INfORM (International Network for Orofacial Pain and Related Disorders Methodology) of the International Association for Dental Research has been one of the driving forces behind the development and implementation of comprehensive sets of tools for such assessments. However, as a prerequisite for the desired global implementation, reliable and valid tools that are also brief, easy to translate, and culturally adaptable need to be further developed and tested. Some of the groundwork to facilitate this process has already been carried out. In addition, a working group within INfORM has developed a short clinical assessment tool for orofacial pain diagnostics that is near completion and will soon be ready for dissemination. Ultimately, reliable and valid orofacial pain assessment is a necessary step toward the development and implementation of appropriate "best buy" interventions that address this major driver of need for oral health care worldwide.

Clinical outcomes in the treatment of unilateral condylar fractures: a cross-sectional study.

The treatment of mandibular condyle fractures has been the subject of considerable discussion, especially whether open or closed treatment should be used. There is a need for practical,evidence-based guidelines, and both objective and subjective parameters should be measured. To date, fewstudies have considered clinically relevant subjective parameters. This study was performed to evaluate the outcomes of the treatment of condylar fractures using the Mandibular Function Impairment Questionnaire (MFIQ) and the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) and to compare the outcomes of open and the closed treatment. Patients with condylar fractures and at least 1year of follow-up were examined. These patients completed the MFIQ and other questionnaires, and were examined according to the DC/TMD. Seventy-four of 171 eligible patients participated in this study. The mean MFIQ score was 10.70 (standard error 2.9) in the open group and 4.96 (standard error 1.3) in the closed group (P=0.023), an outcome in favour of the closed treatment group. Examination according to the DC/TMD did not reveal a significant prevalence of TMD complaints. Closed treatment appears to be a safe and appropriate modality for most unilateral condylar fractures. Although the open group in general showed similar outcomes, this treatment should be reserved for limited indications.

Effects of intense chewing exercises on the masticatory sensory-motor system.

Nociceptive substances, injected into the masseter muscle, induce pain and facilitate the jaw-stretch reflex. It is hypothesized that intense chewing would provoke similar effects. Fourteen men performed 20 bouts of 5-minute chewing. After each bout, 20 min and 24 hrs after the exercise, muscle fatigue and pain scores and the normalized reflex amplitude from the left masseter muscle were recorded. Before, 20 min, and 24 hrs after the exercise, signs of temporomandibular disorders and pressure-pain thresholds of the masticatory muscles were also recorded. Fatigue and pain scores had increased during the exercise (P < 0.001), but the reflex amplitude did not (P = 0.123). Twenty minutes after the exercises, 12 participants showed signs of myofascial pain or arthralgia. Pressure-pain thresholds were decreased after 20 min (P = 0.009) and 24 hrs (P = 0.049). Intense chewing can induce fatigue, pain, and decreased pressure-pain thresholds in the masticatory muscles, without concomitant changes in the jaw-stretch reflex amplitude.