Frequency of Four-dimensional Oral Health Problems across Dental Fields - a Comparative Survey of Slovenian and International Dentists.

Objectives: To compare the frequency of patients' oral health problems and prevention needs among Slovenian and international dentists with the aim to validate the four oral health-related quality of life (OHRQoL) dimensions across six clinical dental fields in all World Health Organization (WHO) regions.

Methods: An anonymous electronic survey in the English language was designed using Qualtrics software. A probability sampling for Slovenia and a convenience sampling strategy for dentist recruitment was applied for 31 countries.

Even mild catastrophic thinking is related to pain intensity in individuals with painful temporomandibular disorders.

Aims: Temporomandibular disorders (TMD) are often associated with psychological comorbidities. One such comorbidity is pain catastrophising, that is, exaggeration of negative consequences of a painful event. The aim was to investigate catastrophising in individuals with painful TMD compared to controls and the association between catastrophising and pain intensity, number of pain sites and functional limitations.

Pediatric patients' reasons for visiting dentists in all WHO regions.

Background: Oral Function, Orofacial Pain, Orofacial Appearance, and Psychosocial Impact are the four oral health-related quality of life (OHRQoL) dimensions (4D) or areas in which oral disorders impact pediatric patients. Using their dentists' assessment, the study aimed to evaluate whether pediatric dental patients' oral health concerns fit into the 4D of the Oral Health-Related Quality of Life (OHRQoL) construct.

Methods: Dentists who treat children from 32 countries and all WHO regions were selected from a web-based survey of 1580 international dentists.

Why Patients Visit Dentists - A Study in all World Health Organization Regions.

Objective: The dimensions of oral health-related quality of life (OHRQoL) Oral Function, Orofacial Pain, Orofacial Appearance, and Psychosocial Impact are the major areas where patients are impacted by oral diseases and dental interventions. The aim of this study was to evaluate whether dental patients' reasons to visit the dentist fit the 4 OHRQoL dimensions.

Methods: Dentists (N = 1580) from 32 countries participated in a web-based survey.

Chronic Neuropathic Pain: It's about the Rhythm.

The neural mechanisms underlying the development and maintenance of chronic neuropathic pain remain unclear. Evidence from human investigations suggests that neuropathic pain is associated with altered thalamic burst firing and thalamocortical dysrhythmia. Additionally, experimental animal investigations show that neuropathic pain is associated with altered infra-slow (<0.

Experimental jaw muscle pain increases pain scores and jaw movement variability in higher pain catastrophizers.

Aims: To investigate differences between higher and lower pain catastrophizers in the effects of hypertonic saline-evoked jaw muscle pain on pain perception and jaw movement.

Methods: Repetitive open/close jaw movements were recorded in 28 asymptomatic participants (20 men, 8 women; ages 25 to 62 years) during continuous infusion of 5% hypertonic saline or isotonic saline into the right masseter muscle. All participants completed the McGill Pain Questionnaire; the Depression, Anxiety and Stress Scales; and the Jaw Function Limitation Scale.

Unraveling the effects of plasticity and pain on personality.

Unlabelled: Chronic pain resulting from physical stressors is often accompanied by psychological disorders such as depression. Although depressive disorders are associated with changes in brain anatomy, it remains unknown if changes in brain anatomy associated with increased state depression levels also occur in patients with chronic pain. When individuals are experiencing physical stressors such as ongoing pain, depressive personality traits may predispose them to develop depressive states.

Trigeminal nerve anatomy in neuropathic and non-neuropathic orofacial pain patients.

Unlabelled: Trigeminal neuralgia, painful trigeminal neuropathy, and painful temporomandibular disorders (TMDs) are chronic orofacial pain conditions that are thought to have fundamentally different etiologies. Trigeminal neuralgia and neuropathy are thought to arise from damage to or pressure on the trigeminal nerve, whereas TMD results primarily from peripheral nociceptor activation. This study sought to assess the volume and microstructure of the trigeminal nerve in these 3 conditions.

The effects of capsaicin-induced intraoral mucosal pain on jaw movements in humans.

Aims: To determine whether mucosal pain, evoked through a novel topical capsaicin model, has an effect on jaw movement and whether psychologic factors have an association with any pain-induced movement effects.

Methods: Mandibular movement was recorded from 26 asymptomatic subjects during free opening and closing, resistant opening jaw movements, and free and standardized chewing, at baseline and in test sessions while the subjects were wearing a custom maxillary mouthguard coated with either capsaicin cream (pain group, 13 subjects) or placebo cream (control group, an additional 13 subjects). All subjects completed the Depression Anxiety Stress Scales (DASS) and the Pain Catastrophizing Scale (PCS).

Jaw-movement smoothness during empty chewing and gum chewing.

A major goal of motor coordination is the production of a smooth movement. Jerk-cost, which is an inverse measure of movement smoothness, has been evaluated during gum chewing in previous studies. However, the effect of the gum bolus is still unclear.

Development and validation of a screening checklist for temporomandibular disorders.

Aims: To develop and validate a short screening tool for temporomandibular disorders (TMD) from the comprehensive Research Diagnostic Criteria for TMD (RDC/TMD) assessment.

Methods: Complete RDC/TMD assessments of four subject groups (96 TMD; 102 dental pain; 68 headache; 115 no-pain patients) were compared. Classification tree and multiple logistic regression analyses were utilized to develop the tool.

Chewing in temporomandibular disorder patients: an exploratory study of an association with some psychological variables.

Aims: To compare kinematic parameters (ie, amplitude, velocity, cycle frequency) of chewing and pain characteristics in a group of female myofascial temporomandibular disorder (TMD) patients with an age-matched control female group, and to study correlations between psychological variables and kinematic variables of chewing.

Methods: Twenty-nine female participants were recruited. All participants were categorized according to the Research Diagnostic Criteria for TMD (RDC/TMD) into control (n = 14, mean age 28.

Jaw motor plasticity in health and disease.

The human jaw's structure-function relationships are complex. A recent example of this complexity is the lateral pterygoid muscle which we now consider as a single unit made up of functional regions with activity in each dependent on the biomechanical demands of the task. We have also characterised the effects on the jaw motor system of pain or exercise, as examples of how the jaw motor system adapts.

From movement to models: a tribute to professor Alan G. Hannam.

This tribute article to Professor Alan G. Hannam is based on 7 presentations for him at the July 1, 2008 symposium honoring 3 "giants" in orofacial neuroscience: Professors B. J.

Effects of experimental pain on jaw muscle activity during goal-directed jaw movements in humans.

To study the effects of masseter muscle pain on jaw muscle electromyographic (EMG) activity during goal-directed tasks. Mandibular movement was tracked and EMG activity was recorded from bilateral masseter, and right posterior temporalis, anterior digastric, and inferior head of lateral pterygoid muscles in 22 asymptomatic subjects at postural jaw position, and during three tasks: (a) protrusion, (b) contralateral (left), (c) open jaw movement. Tasks were performed during three conditions: control (no infusion), test 1 [continuous infusion into right masseter of 4.

Orofacial pain and jaw muscle activity: a new model.

Two major theories proposed to explain the effect of pain on muscle activity are the Vicious Cycle Theory and the Pain Adaptation Model. Comprehensive reviews demonstrate conflicting or limited evidence in support of a critical aspect of the Vicious Cycle Theory, namely that pain leads to increased muscle activity. The Pain Adaptation Model proposes that changes in muscle activity limit movement and thereby protect the sensorimotor system from further injury.

Threshold properties of single motor units in superior head of human lateral pterygoid muscle.

Unlabelled: The superior head of the human lateral pterygoid muscle (SHLP) may play a similar role in jaw movement as the inferior head (IHLP).

Objective: The aim was to determine whether threshold properties of single motor units (SMUs) within SHLP during jaw tasks were comparable to those identified for IHLP.

Design: In 24 human subjects, SMUs were recorded intramuscularly from computer-tomography verified sites within SHLP during standardised jaw tasks recorded by a jaw-tracking device.

Human jaw and muscle modelling.

Dynamic mathematical modelling is an invaluable method to help understand the biomechanics of the anatomically and functionally complex masticatory system. It provides insight into variables which are impossible to measure directly such as joint loads and individual muscle tensions, and into physical relationships between jaw structure and function. Individual parameters can be modified easily to understand their influence on function.

The human lateral pterygoid muscle.

One of the jaw muscles particularly implicated in temporomandibular disorders (TMD), a common form of non-dental chronic orofacial pain, is the human lateral pterygoid muscle. The precise role of this muscle in TMD is unclear as is the nature of the interaction between pain and motor function particularly involving this muscle. This research group has adopted a two-stage approach to studying the effects of pain on motor function.

A method for studying jaw muscle activity during standardized jaw movements under experimental jaw muscle pain.

This paper describes a method for studying superficial and deep jaw muscle activity during standardized jaw movements under experimental jaw muscle pain. In 22 healthy adults, pain was elicited in the right masseter muscle via tonic infusion of 4.5% hypertonic saline and which resulted in scores of 30-60 mm on a 100-mm visual analogue scale.