Oral Jaws Research Articles

The involvement of chronic persistent viral infection to various diseases of the oral cavity

Relevance. According to the literature all over the world, there is a tendency to reduce immunological reactivity in humans, this is facilitated by the presence of chronic persistent herpes viral infection. Herpes infection has systemic immunosuppressive effects of the infection on the human body, and also highlighted the role of the virus in a slow occurrence of combined pathology of internal organs and infectious and inflammatory diseases of the oral tissues and periodontium. High interest of specialists to this problem сaused by the necessity of new methods of complex treatment polymorbidity human pathology. Purpose – to assess the degree of involvement of chronic cytomegalovirus persistence in a number of dental diseases.Materials and methods. In 67 patients dental surgery underwent surgery removal of benign tumors of the soft tissues of the oral cavity, periodontium and jaws, had a clinical blood analysis, blood testing for serological signs of chronic persistence of cytomegalovirus infection (antibodies to CMV Ig G (anti CMV IgG), PCR for CMV in blood and saliva, and also studied the cellular composition of blood immunogram. The age of patients averaged 46 years. Рatients were divided according to the nosological principle into 4 groups. The first group consisted of patients with periapical foci of chronic odontogenic inflammation and radicular cysts of the jaws. The second group consisted of persons with oral fibroids of different localization. The third group is patients with retention cysts of small salivary glands of the oral mucosa. The fourth group – patients with poligamy various locations. All operations are performed outside the phase of acute inflammation. The material obtained after the operation underwent histological examination.Results. Serological signs of chronic persistence of cytomegalovirus infection were revealed in all examined patients, the level of anti CMV Ig was 225 ± 25 U / ml (at the rate of 0.00-0.50 U / ml) (p 0.01). Also, all patients showed lymphocytosis of blood and this corresponded to the same type of changes in the cellular composition of the immunogram with a decrease in the quantitative parameters of B-lymphocytes (CD19+ CD3- ), true natural "killers" (NK-cells) (CD3- CD56+ CD45+ ), NK-cells cytokine-producing (CD3- CD16+ Cd56brightcd45+ ), NK-cells cytolytic (CD3- CD16+ (orhigh) sd56dimcd45+ ). The results of the histological study showed that focal mononuclear and lymphohistiocytic cell infiltration with giant cells with large nuclei are more often detected in areas of the oral mucosa in all patients with radical and retention cysts.Conclusion. The Obtained results demonstrate that in patients regardless of surgical dental diagnosis, chronic persistence of cytomegalovirus with the same type of hematological, immunological abnormalities was revealed. In areas of the oral mucosa with retention cysts of small salivary glands and with radicular cysts, focal lymphohistiocytic and mononuclear cell infiltration with giant cells with large nuclei was revealed.

Drivers and dynamics of a massive adaptive radiation in cichlid fishes.

Adaptive radiation is the likely source of much of the ecological and morphological diversity of life1-4. How adaptive radiations proceed and what determines their extent remains unclear in most cases1,4. Here we report the in-depth examination of the spectacular adaptive radiation of cichlid fishes in Lake Tanganyika. On the basis of whole-genome phylogenetic analyses, multivariate morphological measurements of three ecologically relevant trait complexes (body shape, upper oral jaw morphology and lower pharyngeal jaw shape), scoring of pigmentation patterns and approximations of the ecology of nearly all of theapproximately 240 cichlid species endemic to Lake Tanganyika, we show that the radiation occurred within the confines of the lake and that morphological diversification proceeded in consecutive trait-specific pulses of rapid morphospace expansion. We provide empirical support for two theoretical predictions of how adaptive radiations proceed, the 'early-burst' scenario1,5 (for body shape) and the stages model1,6,7 (for all traits investigated). Through the analysis of two genomes per species and by taking advantage of the uneven distribution of species in subclades of the radiation, we further show that species richness scales positively with per-individual heterozygosity, but is not correlated with transposable element content, number of gene duplications or genome-wide levels of selection in coding sequences.

Common benign and malignant oral mucosal disease.

Mucosal diseases of the oral cavity arerelatively common, and patients oftenseek initial assessment from theirgeneralpractitioner. The aim of this article is to provide anoverview of common oral mucosal diseases to help with formulating a differential diagnosis and stratifying theurgency of referral. Pathological mucosal conditions of the oral cavity and jaws commonly present asa mucosal ulcer or a white, red or pigmented lesion. In this review, the authors outline the most common conditions organised according to their clinical presentation and describe their typical appearance and management.

Clinicopathological analysis of 847 odontogenic cysts in North Indian population examined over 10 years' period: A retrospective study

Aims and Objectives: The purpose of this study is to analyze and report the prevalence, frequency, sex distribution, site distribution, and clinicopathological features of odontogenic cysts in an institutional academic dental hospital by studying the biopsy specimens and clinical records obtained from the archives of the Department of Oral and Maxillofacial Surgery and Department of Pathology, AMU, Aligarh, India, during the past 10 years. Materials and Methods: Data on odontogenic jaw cysts treated between 2009 and 2018 were retrieved from clinical files; imaging and histopathology reports and a total of 847 patients were included. In each case, we analyzed age, gender, type and number of cysts, and cyst location. Imaging characteristics and pathologies associated with cystic lesions were also determined. Results: Diagnosis of odontogenic cyst was made in 847 cases and accounted for 10.9% of all lesions biopsied (7748) throughout the period. Mean age of the patient was 28.2 years, and 57.3% were males. The overall male to female ratio was 1.34:1. Radicular cyst was most prevalent histological type (54.54%) followed by dentigerous cyst, odontogenic keratocyst, lateral periodontal cyst, residual cyst, botyroid odontogenic cyst, gingival cyst. The distribution of cysts was nearly equal in the mandible (51.6%) and maxilla (48.4%) with the cysts most commonly located in anterior maxilla and posterior mandible. The most prevalent radiological feature of these lesions was unilocular cyst (88.78%). Associated pathologies with cystic lesions such as displacement and resorption of teeth occurred in 14.7%. Conclusions: This study revealed that prevalence, distribution, and characteristics of odontogenic cysts of oral cavity and jaws in the North Indian population, have some differences as well as similarities with the findings of studies in different populations.

Ecological divergence in sympatry causes gene misexpression in hybrids.

Ecological speciation occurs when reproductive isolation evolves as a byproduct of adaptive divergence between populations. Selection favouring gene regulatory divergence between species could result in transgressive levels of gene expression in F1 hybrids that may lower hybrid fitness. We combined 58 resequenced genomes with 124 transcriptomes to identify patterns of hybrid gene misexpression that may be driven by adaptive regulatory divergence within a young radiation of Cyprinodon pupfishes, which consists of a dietary generalist and two trophic specialists-a molluscivore and a scale-eater. We found more differential gene expression between closely related sympatric specialists than between allopatric generalist populations separated by 1,000km. Intriguingly, 9.6% of genes that were differentially expressed between sympatric species were also misexpressed in F1 hybrids. A subset of these genes were in highly differentiated genomic regions and enriched for functions important for trophic specialization, including head, muscle and brain development. These regions also included genes that showed evidence of hard selective sweeps and were significantly associated with oral jaw length-the most rapidly diversifying skeletal trait in this radiation. Our results indicate that divergent ecological selection in sympatry can contribute to hybrid gene misexpression which may act as a reproductive barrier between nascent species.

Convergent Evolution of Cichlid Fish Pharyngeal Jaw Dentitions in Mollusk-Crushing Predators: Comparative X-Ray Computed Tomography of Tooth Sizes, Numbers, and Replacement.

Dental convergence is a hallmark of cichlid fish adaptive radiations. This type of repeated evolution characterizes both the oral jaws of these fishes as well as their pharyngeal jaws that are modified gill arches used to functionally process prey like hard-shelled mollusks. To test several hypotheses regarding the evolution of cichlid crushing pharyngeal dentitions, we used X-ray computed tomography scans to comparatively examine dental evolution in the pharyngeal jaw of a diversity of New World Heroine cichlid lineages. The substantial variation in erupted tooth sizes and numbers as well as replacement teeth found in these fishes showed several general patterns. Larger toothed species tended to have fewer teeth suggesting a potential role of spatial constraints in cichlid dental divergence. Species with larger numbers of erupted pharyngeal teeth also had larger numbers of replacement teeth. Replacement tooth size is almost exactly predicted (r = 0.99) from the size of erupted teeth across all of the species. Mollusk crushing was, therefore, highly associated with not only larger pharyngeal teeth, but also larger replacement teeth. Whether dental divergence arises as a result of environmental induced plasticity or originates via trophic polymorphism as found in the species Herichthys minckleyi, there appear to be general rules that structure interspecific divergence in cichlid pharyngeal erupted and replacement dentitions.

A Genomic Cluster Containing Novel and Conserved Genes is Associated with Cichlid Fish Dental Developmental Convergence.

The two toothed jaws of cichlid fishes provide textbook examples of convergent evolution. Tooth phenotypes such as enlarged molar-like teeth used to process hard-shelled mollusks have evolved numerous times independently during cichlid diversification. Although the ecological benefit of molar-like teeth to crush prey is known, it is unclear whether the same molecular mechanisms underlie these convergent traits. To identify genes involved in the evolution and development of enlarged cichlid teeth, we performed RNA-seq on the serially homologous-toothed oral and pharyngeal jaws as well as the fourth toothless gill arch of Astatoreochromis alluaudi. We identified 27 genes that are highly upregulated on both tooth-bearing jaws compared with the toothless gill arch. Most of these genes have never been reported to play a role in tooth formation. Two of these genes (unk, rpfA) are not found in other vertebrate genomes but are present in all cichlid genomes. They also cluster genomically with two other highly expressed tooth genes (odam, scpp5) that exhibit conserved expression during vertebrate odontogenesis. Unk and rpfA were confirmed via in situ hybridization to be expressed in developing teeth of Astatotilapia burtoni. We then examined expression of the cluster's four genes in six evolutionarily independent and phylogenetically disparate cichlid species pairs each with a large- and a small-toothed species. Odam and unk commonly and scpp5 and rpfA always showed higher expression in larger toothed cichlid jaws. Convergent trophic adaptations across cichlid diversity are associated with the repeated developmental deployment of this genomic cluster containing conserved and novel cichlid-specific genes.

Longer development provides first-feeding fish time to escape hydrodynamic constraints.

What is the functional effect of prolonged development? By controlling for size, we quantify first-feeding performance and hydrodynamics of zebrafish and guppy offspring (5 ± 0.5 mm in length), which differ fivefold in developmental time and twofold in ontogenetic state. By manipulating water viscosity, we control the hydrodynamic regime, measured as Reynolds number. We predicted that if feeding performance were strictly the result of hydrodynamics, and not development, feeding performance would scale with Reynolds number. We find that guppy offspring successfully feed at much greater distances to prey (1.0 vs. 0.2 mm) and with higher capture success (90 vs. 20%) compared with zebrafish larvae, and that feeding performance was not a result of Reynolds number alone. Flow visualization shows that zebrafish larvae produce a bow wave ~0.2 mm in length, and that the flow field produced during suction does not extend beyond this bow wave. Due to well-developed oral jaw protrusion, the similar-sized suction field generated by guppy offspring extends beyond the horizon of their bow wave, leading to successful prey capture from greater distances. These findings suggest that prolonged development and increased ontogenetic state provides first-feeding fish time to escape the pervasive hydrodynamic constraints (bow wave) of being small.

Decoupled jaws promote trophic diversity in cichlid fishes.

Functional decoupling of oral and pharyngeal jaws is widely considered to have expanded the ecological repertoire of cichlid fishes. But, the degree to which the evolution of these jaw systems is decoupled and whether decoupling has impacted trophic diversification remains unknown. Focusing on the large Neotropical radiation of cichlids, we ask whether oral and pharyngeal jaw evolution is correlated and how their evolutionary rates respond to feeding ecology. In support of decoupling, we find relaxed evolutionary integration between the two jaw systems, resulting in novel trait combinations that potentially facilitate feeding mode diversification. These outcomes are made possible by escaping the mechanical trade-off between force transmission and mobility, which characterizes a single jaw system that functions in isolation. In spite of the structural independence of the two jaw systems, results using a Bayesian, state-dependent, relaxed-clock model of multivariate Brownian motion indicate strongly aligned evolutionary responses to feeding ecology. So, although decoupling of prey capture and processing functions released constraints on jaw evolution and promoted trophic diversity in cichlids, the natural diversity of consumed prey has also induced a moderate degree of evolutionary integration between the jaw systems, reminiscent of the original mechanical trade-off between force and mobility.

The evolution of specialized dentition in the deep-sea lanternfishes (Myctophiformes).

The evolution of heterodonty, the possession of varied tooth morphologies on the jaws of animals, has been relatively unexplored in ray-finned fishes compared to terrestrial vertebrates, and to an even lesser degree in deep-sea fish lineages. Lanternfishes (Myctophiformes) are an abundant and species-rich group endemic to deep-sea pelagic habitats. In this study, we document the presence of heterodonty on the oral jaws of lanternfishes, identifying differing anatomical and positional variations of dentition. We survey the anatomical variation in tooth morphology on the oral jaws of 114 lanternfish species across 37 genera and integrate our findings with a hypothesis of evolutionary relationships of lanternfishes to infer the number of times heterodonty evolved in this lineage. Our results indicate that heterodonty evolved at least six separate times on the oral jaws of lanternfishes, occurring as variable tooth morphologies in combination with villiform teeth. These combinations of tooth types include villiform plus hooked teeth, villiform plus hooked and recurved teeth, villiform plus spade, tricuspid, and hooked teeth, and villiform plus caniniform teeth. The reoccurring evolution of hooked teeth on the premaxilla and dentary in lanternfishes suggests heterodonty may serve an important functional role in their pelagic deep-sea environment. Hooked teeth could aid in securing and retaining prey in the oral cavity and allow for species to specialize on differing food resources, vital attributes for organisms living in open-ocean habitats.

Performance of a porous composite scaffold containing silk fibroin: Applied research repair on oral jaw epithelial defects

Application research on repairing oral and maxillofacial epithelial defects with filin-protein porous composite scaffold. The silk fibroin solution was synthesized by hydrothermal synthesis, and the film was prepared by stirring and pouring. Then silk fibroin film and silk fibroin freeze-dried support were prepared by stirring and smooth casting. It was characterized by FTIR, mechanical properties, dissolution detection, contact Angle and SEM. To evaluate the performance of this material in repairing rabbit oral mucosa and rabbit skin epithelial defects. The characterization shows that the material has good contact Angle, mechanical properties, dissolution and biocompatibility. It has good repair function to rabbit oral epithelial tissue and skin epithelial tissue. Silk fibroin has excellent and unique properties. It has good development prospects and great clinical value in tissue regeneration.

Histo-Epidemiological Profile of Head and Neck Cancers in Benin

Background: The collection of data on cancers is essential to assess their importance in a population and plan control strategies. In Benin as in many sub-Saharan Africa countries, cancer data are often not well informed. Purpose: To study the epidemiological and anatomopathological profiles of head and neck cancers. Methods: This was a descriptive cross-sectional study of head and neck cancers in Benin from January 2009 to 31 December 2014. These tumours were collected in the registers of the 5 anatomy-pathological laboratories in Benin as well as in that of the only hospital in the country that sends its requests for histological examination abroad. Results: During the period, 611 cases of head and neck tumour were reported, including 298 malignant cases, or 48.8%. The average age was 45.3 ± 18.7 years (extremes: 1 year and 91 years) with a maximum of cases between 50 and 60 years (19.1%). The sex ratio was 1.2. The cancers occurred mainly in the pharynx (27.9%), the oral cavity (19.8%), the nose, sinuses and jaws (18.1%), the thyroid (12.8%), the salivary glands (8.7%) and the larynx (8.4%). They were of epithelial origin in 79.5% of cases, mainly squamous cell carcinomas (50.3%) and lymphomas in 12.8% of cases. Conclusion: Head and neck cancer is preventable. A special place should be given to the fight against cancer in Benin. Strategies to prevent and manage these cancers cannot be put in place without accurate data collection.

Ecological redundancy between coral reef sharks and predatory teleosts

Reef sharks may be ecologically redundant, such that other mesopredatory fishes compensate for their functions when they decline in number, preventing trophic cascades. Oral jaw gape, hereafter referred to as gape, determines maximum prey size in many piscivores and therefore affects the size structure of prey assemblages. Here, we examine whether gape and maximum prey size differ between five species of reef shark and 21 species of teleost (n = 754) using data collected from 38 reefs in the Indo-Pacific. Sharks displayed relatively small gape dimensions compared to most teleost species and, at smaller sizes, the giant trevally Caranx ignobilis and other teleosts may be able to consume larger prey than similar-sized sharks. However, ecological redundancy between reef sharks and teleosts appears to decline at larger sizes, such that the grey reef shark Carcharhinus amblyrhynchos, for example, may be capable of consuming larger prey than any other reef predator at its largest sizes, regardless of prey body shape. Moreover, sharks may be able to consume proportionally larger prey as they grow, in contrast to reef teleosts, which may largely be limited by their gapes to ever-smaller prey as a proportion of their body size. Our results also suggest that reef sharks may be unable to swallow whole prey that are > 36% of their length, consistent with gut-content studies. Conservation of reef ecological function may therefore depend not only on the protection of sharks but also particular size classes and key components of the mesopredatory guild.

Similar ecology, different morphology: Three new species of oral-mollusc shellers from Lake Edward.

Lake Edward, East Africa, harbours a largely understudied assemblage of haplochromine cichlids that displays a range of adaptions to various specialised trophic niches. In this system, we discovered specimens of Haplochromis with morphologies similar to those of oral-mollusc shellers from Lake Victoria. These morphologies are characterised by short oral jaws with stout teeth that are used either to crush molluscs or to grab the soft bodies of snails and wrench them out of their shells. A morphometric study on 47 specimens from Lake Edward revealed the presence of three new species with an oral-shelling morphology: Haplochromis concilians sp. nov., H. erutus sp. nov. and H. planus sp. nov. All three species are formally described. Stomach-content observations confirmed an opportunistic oral-shelling ecology for H. concilians sp. nov. and H. erutus sp. nov. Within H. planus sp. nov., only large specimens displayed a specialised oral-shelling morphology, but their stomachs were nearly empty, while small specimens consumed mainly Ostracoda and Hydrachnidia. Remarkably, the three species differed considerably in morphology from each other, but they each resembled oral-sheller species from Lake Victoria.

Extreme premaxillary protrusion in the king-of-the-salmon, Trachipterus altivelis.

The king-of-the-salmon, Trachipterus altivelis (Lampriformes), has an unusual set of oral jaws which allow it the ability to protrude the entire upper jaw, containing the premaxilla and the maxilla bones, to extreme distances. Here, we provide a short description of the cranial anatomy and mechanism of jaw protrusion in T. altivelis using hand-drawn illustrations (by KF), supplemented by CT-scans. We then place the protrusion abilities of T. altivelis into context by comparing anatomical jaw protrusion with protrusion from other members of the Lampriformes, other unrelated species with highly protrusile jaws, and unrelated species with more stereotypical amounts of jaw protrusion. Through these comparisons we demonstrate that T. altivelis is indeed, capable of some of the most extreme premaxillary protrusion as of yet discovered, even when taking into account the extreme morphological modifications that facilitate said protrusion. That is to say, T. altivelis can protrude the premaxilla farther than one would predict from the length of the ascending process alone.

Divergence in larval jaw gene expression reflects differential trophic adaptation in haplochromine cichlids prior to foraging

BackgroundUnderstanding how variation in gene expression contributes to morphological diversity is a major goal in evolutionary biology. Cichlid fishes from the East African Great lakes exhibit striking diversity in trophic adaptations predicated on the functional modularity of their two sets of jaws (oral and pharyngeal). However, the transcriptional basis of this modularity is not so well understood, as no studies thus far have directly compared the expression of genes in the oral and pharyngeal jaws. Nor is it well understood how gene expression may have contributed to the parallel evolution of trophic morphologies across the replicate cichlid adaptive radiations in Lake Tanganyika, Malawi and Victoria.ResultsWe set out to investigate the role of gene expression divergence in cichlid fishes from these three lakes adapted to herbivorous and carnivorous trophic niches. We focused on the development stage prior to the onset of exogenous feeding that is critical for understanding patterns of gene expression after oral and pharyngeal jaw skeletogenesis, anticipating environmental cues. This framework permitted us for the first time to test for signatures of gene expression underlying jaw modularity in convergent eco-morphologies across three independent adaptive radiations. We validated a set of reference genes, with stable expression between the two jaw types and across species, which can be important for future studies of gene expression in cichlid jaws. Next we found evidence of modular and non-modular gene expression between the two jaws, across different trophic niches and lakes. For instance, prdm1a, a skeletogenic gene with modular anterior-posterior expression, displayed higher pharyngeal jaw expression and modular expression pattern only in carnivorous species. Furthermore, we found the expression of genes in cichlids jaws from the youngest Lake Victoria to exhibit low modularity compared to the older lakes.ConclusionOverall, our results provide cross-species transcriptional comparisons of modularly-regulated skeletogenic genes in the two jaw types, implicating expression differences which might contribute to the formation of divergent trophic morphologies at the stage of larval independence prior to foraging.

Extending the Geometric Approach for Studying Biomechanical Motions.

Whether it is swimming, walking, eating, or jumping, motions are a fundamental way in which organisms interact with their environment. Understanding how morphology contributes to motion is a primary focus of kinematic research and is necessary for gaining insights into the evolution of functional systems. However, an element that is largely missing from traditional analyses of motion is the spatial context in which they occur. We explore an application of geometric morphometrics (GM) for analyzing and comparing motions to evaluate the outputs of biomechanical linkage models. We focus on a common model for oral jaw mechanics of perciform fishes, the fourbar linkage, using GM to summarize motion as a trajectory of shape change. Two traits derived from trajectories capture the total kinesis generated by a linkage (trajectory length) and the kinematic asynchrony (KA) of its mobile components (trajectory nonlinearity). Oral jaw fourbar data from two subfamilies of Malagasy cichlids were used to generate form-function landscapes, describing broad features of kinematic diversity. Our results suggest that kinesis and KA have complex relationships with fourbar morphology, each displaying a pattern in which different shapes possess equivalent kinematic trait values, known as many-to-one mapping of form-to-function. Additionally, we highlight the observation that KA captures temporal differences in the activation of motion components, a feature of kinesis that has long been appreciated but was difficult to measure. The methods used here to study fourbar linkages can also be applied to more complex biomechanical models and broadly to motions of live organisms. We suggest that they provide a suitable alternative to traditional approaches for evaluating linkage function and kinematics.

Adaptive Diversification of the Lateral Line System during Cichlid Fish Radiation

SummaryThe mechanosensory lateral line system is used by fishes to sense hydrodynamic stimuli in their environment. It provides information about flow regimes, proximity to substrate, and the presence and identity of prey and predators and represents a means of receiving communication signals from other fish. Thus we may expect lateral line system structures to be under strong divergent selection during adaptive radiation. Here, we used X-ray micro-computed tomography scans to quantify variation in cranial lateral line canal morphology within the adaptive radiation of Lake Malawi cichlids. We report that cranial lateral line canal morphology is strongly correlated with diet and other aspects of craniofacial morphology, including the shape of oral jaws. These results indicate an adaptive role for the lateral line system in prey detection and suggest that diversification of this system has taken an important role in the spectacular evolution of Lake Malawi's cichlid fish diversity.

Functional diversity in biters: the evolutionary morphology of the oral jaw system in pacus, piranhas and relatives (Teleostei: Serrasalmidae)

AbstractSerrasalmid fishes form a highly specialized group of biters that show a large trophic diversity, ranging from pacus able to crush seeds to piranhas capable of cutting flesh. Their oral jaw system has been hypothesized to be forceful, but variation in bite performance and morphology with respect to diet has not previously been investigated. We tested whether herbivorous species have higher bite forces, larger jaw muscles and more robust jaws than carnivorous species. We measured in vivo and theoretical bite forces in 27 serrasalmid species. We compared the size of the adductor mandibulae muscle, the jaw mechanical advantages, the type of jaw occlusion, and the size and shape of the lower jaw. We also examined the association between bite performance and functional morphological traits of the oral jaw system. Contrary to our predictions, carnivorous piranhas deliver stronger bites than their herbivorous counterparts. The size of the adductor mandibulae muscle varies with bite force and muscles are larger in carnivorous species. Our study highlights an underestimated level of functional morphological diversity in a fish group of exclusive biters. We provide evidence that the trophic specialization towards carnivory in piranhas results from changes in the configuration of the adductor mandibulae muscle and the lower jaw shape, which have major effects on bite performance and bite strategy.

Bruxism, myoarthropathy and psychosomatics

Bruxism and myoarthrophathy lead to a complex set of burdens that can involve both medical and psychological aspects. Muscular tension due to stress affects these burdens and leads to chronic pain. Using a stress model, it was explained how the individual processing of stress leads to varying negative effects on oral health and jaw function. Through a short survey, it is possible for the dentist to assess the extent of the chronic pain and the associated psychosocial burdens, and, when necessary, encourage the patient to undertake psychological guidance. By learning relaxation techniques and pain coping mechanisms, the pain can be reduced. In order to achieve a long lasting successful treatment, one must consider both medical and psychosomatic aspects.