Occlusal disorders among patients with total clefts of lip, alveolar bone, and palate

Family-based GWAS for dental class I malocclusion and clefts

BACKGROUND

Individuals born with cleft lip and/or palate who receive corrective surgery regularly have abnormal growth in the midface region such that they exhibit premaxillary hypoplasia. However, there are also genetic contributions to craniofacial morphology in the midface region, so although these individuals appear to have Class III skeletal discrepancy, their molar relationship may be Class I. Past genome-wide association studies (GWASs) on skeletal Class II and III malocclusion suggested that multiple genetic markers contribute to these phenotypes via a multifactorial inheritance model, but research has yet to examine the genetic markers associated with dental Class I malocclusion. Thus, our goal was to conduct a family based GWAS to identify genes across the genome that are associated with Class I malocclusion, as defined by molar relations, in humans with and without clefts.

METHODS

Our cohort consisted of 739 individuals from 47 Filipino families originally recruited in 2006 to investigate the genetic basis of orofacial clefts. All individuals supplied blood samples for DNA extraction and genotyping, and a 5,766 single nucleotide polymorphism (SNP) custom panel was used for the analyses. We performed a transmission disequilibrium test for participants with and without clefts to identify genetic contributors potentially involved with Class I malocclusion.

RESULTS

In the total cohort, 13 SNPs had associations that reached the genomic control threshold (p < 0.005), while five SNPs were associated with Class I in the cohort of participants without clefts, including four associations that were identified in the total cohort. The associations for the SNPs ABCA4 rs952499, SOX1-OT rs726455, and RORA rs877228 are of particular interest, as past research found associations between these genes and various craniofacial phenotypes, including cleft lip and/or palate.

CONCLUSIONS

These findings support the multifactorial inheritance model for dental Class I malocclusion and suggest a common genetic basis for different aspects of craniofacial development.

Correlation between findings of the oral myofunctional clinical assessment, pressure and electromyographic activity of the tongue during swallowing in individuals with different orofacial myofunctional disorders

PURPOSE

To correlate the findings regarding the myofunctional orofacial examination, tongue pressure and surface electromyography (sEMG) of deglutition in individuals with different orofacial myofunctional disorders.

METHODS

44 patients (20 males and 24 females, aged between 17 and 63 years old) with different orofacial myofunctional changes were clinically assessed using the Expanded Protocol of Orofacial Myofunctional Evaluation with Scores (OMES-E). In addition, the range of mandibular movements and facial anthropometry were measured, along with the assessment of the tongue pressure (tip and dorsum) and of the electrical activity of the suprahyoid muscles during deglutition, using surface electromyography (sEMG).

RESULTS

The statistical analysis found weak correlations between tongue dorsum pressure values, suggesting that the greater the measurement of the lower third of the face, the lower the pressure of the tongue dorsum; the greater the measurement of the overlaps (vertical and horizontal), the higher the pressure of the tongue dorsum; the higher the score from the orofacial evaluation and orofacial functions assessment, the higher the pressure of the tongue dorsum; and the higher the pressure of the tongue dorsum, the higher the pressure of the tongue tip.

CONCLUSION

The present study results indicate that the orofacial myofunctional changes found in different groups of patients are more related to the maxillomandibular discrepancies than to the pathologies investigated herein.

Unusual Indications of Teeth Transplantation: A Literature Review

Dental implants are one of the best valid tooth replacement options, though these are not always appropriate in growing young patients. Tooth autotransplantation can be indicated then. However, this is not the only scenario where dental transplantation can be indicated. This comprehensive literature review discusses a wide range of unusual indications of dental transplantation as reported throughout the medical literature. Surprisingly, these indications include management of some developmental dental anomalies, hypodontia, oroantral communications, alveolar clefts, deficient alveolar ridges, ectopic teeth, and maxillofacial injuries. Limited high-quality evidence in this field regarding most of these unusual indications warrants further research of high-quality design.

Regeneration in Experimental Alveolar Bone Defect Using Human Umbilical Cord Mesenchymal Stem Cells

Cleft lip and palate is a congenital disorder including cleft lip, and/or cleft palate, and/or alveolar cleft, with high incidence.The alveolar cleft causes morphological and functional abnormalities. To obtain bone bridge formation and continuous structure between alveolar clefts, surgical interventions are performed from infancy to childhood. However, desirable bone bridge formation is not obtained in many cases. Regenerative medicine using mesenchymal stem cells (MSCs) is expected to be a useful strategy to obtain sufficient bone bridge formation between alveolar clefts. In this study, we examined the effect of human umbilical cord-derived MSCs by transplantation into a rat experimental alveolar cleft model. Human umbilical cords were digested enzymatically and the isolated cells were collected (UC-EZ cells). Next, CD146-positive cells were enriched from UC-EZ cells by magnetic-activated cell sorting (UC-MACS cells). UC-EZ and UC-MACS cells showed MSC gene/protein expression, in vitro. Both cells had multipotency and could differentiate to osteogenic, chondrogenic, and adipogenic lineages under the differentiation-inducing media. However, UC-EZ cells lacked Sox2 expression and showed the lower ratio of MSCs than UC-MACS cells. Thus, UC-MACS cells were transplanted with hydroxyapatite and collagen (HA + Col) into alveolar cleft model to evaluate bone formation in vivo. The results of micro computed tomography and histological staining showed that UC-MACS cells with HA + Col induced more abundant bone formation between the experimental alveolar clefts than HA + Col implantation only. Cells immunopositive for osteopontin were accumulated along the bone surface and some of them were embedded in the bone. Cells immunopositive for human-specific mitochondria were aligned along the newly formed bone surface and in the new bone, suggesting that UC-MACS cells contributed to the bone bridge formation between alveolar clefts. These findings indicate that human umbilical cords are reliable bioresource and UC-MACS cells are useful for the alveolar cleft regeneration.

Identification of Biomechanical Properties of Temporomandibular Discs

Material

Experimental and model tests were conducted on ten fresh porcine temporomandibular joint discs. The average thickness of disc tissue was, accordingly, 2.77 mm for the anterior zone, 3.98 mm for the posterior, and 1.54 mm for the intermediate. The selection of research material in the form of porcine discs was due to the similarity to human discs.

Methods

Discs were loaded in cycles, a temporary course with the amplitude 3 N and frequency 0.07 Hz, and growth in the load was 1 N/s. The selection of load frequency was due to real conditions of temporomandibular joint functioning during mastication. The necessary experimental research was conducted on a testing machine with a measurement range of 2.5 kN.

Results

The obtained numeric calculation results indicate that the number of load cycles has a decisive impact on the limitation of energy dispersion capacity through disc tissue. This phenomenon was observed in all the studies on the disc areas. Along with the growth in load cycles, discs are stiffened, and the most significant stiffness was observed in the intermediate area.

Conclusions

Based on the conducted research, it should be concluded that excessive load affecting temporomandibular joints caused by the act of mastication and occlusal forces generated during parafunction and in people with defined long-term bruxism has crucial importance on biomechanical disc properties and hence the course of temporomandibular joint conditions.

Surface Electromyography as a Method for Diagnosing Muscle Function in Patients with Congenital Maxillofacial Abnormalities

Electromyography (EMG) is the most objective and reliable method available for imaging muscle function and efficiency, which is done by identifying their electrical potentials. In global surface electromyography (sEMG), surface electrodes are located on the surface of the skin, and it detects superimposed motor unit action potentials from many muscle fibers. sEMG is widely used in orthodontics and maxillofacial orthopaedics to diagnose and treat temporomandibular disorders (TMD) in patients, assess stomatognathic system dysfunctions in patients with malocclusions, and monitor orthodontic therapies. Information regarding muscle sEMG activity in subjects with congenital maxillofacial abnormalities is limited. For this reason, the aim of this review is to discuss the usefulness of surface electromyography as a method for diagnosing muscle function in patients with congenital malformations of the maxillofacial region. Original papers on this subject, published in English between 1995 until 2020, are located in the MEDLINE/PubMed database.

Assessment of Masticatory Muscle Function in Patients with Bilateral Complete Cleft Lip and Palate and Posterior Crossbite by means of Electromyography

Aim

The aim of this study was to evaluate the electrical activity of the masticatory muscles in children with a bilateral complete cleft lip and palate (BCCLP) and posterior crossbite as well as in noncleft subjects with no malocclusion. Another purpose of the study was to examine the possible factors associated with this muscle activity.

Methods

The study included 52 children with mixed dentition and Class I occlusions (20 patients with nonsyndromic BCCLP and 32 subjects with no clefts). All the cleft patients had posterior crossbite. The surface electromyography (sEMG) was used to identify the electrical potentials of the temporalis and masseter muscles. The electromyographical (EMG) recordings were taken with a DAB-Bluetooth Instrument (zebris Medical GmbH, Germany) at rest and during maximum voluntary clenching (MVC). The relationships between muscle EMG activity and independent variables were identified through multivariate logistic regression analysis.

Results

The EMG activity of the temporalis muscles at rest was significantly higher in BCCLP patients with malocclusion in comparison with the noncleft subjects with normal occlusion. During MVC, significantly lower electrical potentials of the temporalis and masseter muscles were observed in cleft patients compared to the noncleft group. The presence of BCCLP, unilateral posterior crossbites, increased vertical overlap, and increased overjet are factors strongly associated with higher temporalis muscle EMG activity at rest.

Conclusion

The use of surface electromyography in imaging muscle function showed that children with BCCLP and posterior crossbite exhibited altered masticatory muscle potentials at rest and during clenching. The presence of unilateral posterior crossbites, increased vertical overlap, and increased overjet had a significant impact on temporalis muscle activity in cleft patients. This knowledge is important in the aspect of early and proper diagnosis and orthodontic treatment of malocclusions, thereby achieving correct occlusion and improvement in muscle function.

Surgical maxillary advancement and speech resonance: comparison among cleft types

Purpose This study investigated the influence of the cleft type on the appearance of hypernasality after surgical maxillary advancement (MA). Methods Nasality was determined by measurement of nasalance (acoustic correlate of nasality) by nasometry. The study involved analysis of the nasalance scores of 17 individuals with isolated cleft palate (CP), 118 with unilateral cleft lip and palate (UCLP) and 69 with bilateral cleft lip and palate (BCLP), of both sexes, aged 18 to 28 years, after MA. Only individuals with normal nasalance scores indicating balanced resonance before MA were included in this study. Nasometry was performed 3 days before and 15 months after MA, on average. The proportion of patients who presented nasalance scores indicating hypernasality after surgery was calculated by the ANOVA test, and comparison among the different cleft types was evaluated by the chi-square test (p < 0.05). Results No significant difference was found in the proportions of individuals with hypernasality among the cleft types. Conclusion Nasometry showed that the appearance of hypernasality after MA in individuals with cleft palate with or without cleft lip occurred in similar proportions, regardless of the cleft type.

Orofacial functions and quality of life in children with unilateral cleft lip and palate

This study aimed to evaluate the orofacial functions and oral health-related quality of life (OHRQoL) of children with unilateral cleft lip and palate (UCLP). This case-control study included patients with UCLP matched by sex and age with controls (children without UCLP), resulting in the inclusion of a total of 108 eight- to ten-year-old children. Orofacial functions and OHRQoL were evaluated using the Nordic Orofacial Test-Screening (NOT-S) and the Child Perceptions Questionnaire (CPQ 8-1 0 ), respectively. Data normality was assessed by the Kolmogorov-Smirnov test. Differences and correlations in NOT-S and CPQ 8-1 0 scores between and within the groups were evaluated using Mann-Whitney and Spearman´s correlation tests, respectively. The distribution of NOT-S and global ratings of CPQ 8-1 0 for each group were assessed by Chi-squared/Fisher's Exact tests. The UCLP group had a higher NOT-S total and examination scores than the controls. Dysfunctions related to breathing, facial symmetry/expression, and speech were more frequent in the UCLP patients than in the controls. The UCLP group had higher scores on the social well-being domain than the controls. There was a significant difference between the groups in their ratings in regards to the extent to which their oral condition affected their life overall, with controls perceiving it as somewhat better than patients. In both groups, NOT-S total and interview scores were positively correlated with CPQ 8-1 0 total and domain scores. The NOT-S examination score was only significantly correlated with social domain scores in the control group. The presence of UCLP was associated with clinical signs of orofacial dysfunctions related to breathing, facial symmetry/expression, and speech. Children with UCLP reported more orofacial dysfunctions and negative impacts on social well-being than controls.

Evaluation of Postsurgical Dentofacial Deformities in Children Operated for Correction of Cleft Lip and Palate-A Cross-sectional Study

AIM

The aim of this study is to evaluate the various dentofacial deformities in children who were surgically managed for cleft lip and palate (CLP).

MATERIALS AND METHODS

The study was carried out in 100 surgically managed cleft lip palate children between the ages of 4 years and 15 years. After eliciting a detailed history, a thorough intraoral and extraoral examination was done and details were recorded in a printed proforma with photographs.

DESIGN

Cross-sectional study.

STATISTICAL ANALYSIS USED

All the data were analyzed using SPSS 11.5 software for evaluation using the Chi-square test.

RESULTS

A wide range of surgical, dental, and functional problems among the surgically managed CLP patients were seen.

CONCLUSION

The timing of direct lip repair showed a significant influence on the severity of dentofacial deformities. Lip repair before the age of 1 increases the severity of the deformity.

HOW TO CITE THIS ARTICLE

Joybell C, Krishnan R, et al. Evaluation of Postsurgical Dentofacial Deformities in Children Operated for Correction of Cleft Lip and Palate-A Cross-sectional Study. Int J Clin Pediatr Dent 2019;12(3):165-177.

The Diagnostic Value of Electromyography in Identifying Patients With Pain-Related Temporomandibular Disorders

Introduction: Orofacial pain disorders can be divided into several subgroups. One of them is temporomandibular disorders (TMD) with recognizable signs such as joint noises, limitations in the range of motion, or mandibular deviation during function and symptoms-pain in the muscles or joint. Surface electromyography (sEMG) is a diagnostic tool that ensures reliable and valid evaluation of muscle activity. sEMG detects electrical potentials and on this account may conceivably be employed in the TMD recognition. The aim of this study was to assess the sensitivity, specificity, and accuracy of electromyography in diagnosing subjects with temporomandibular disorders, including pain-free TMD and pain-related TMD. Methods: The sample comprised 88 patients with cleft lip and palate and mixed dentition. TMD has been recognized on the grounds of Axis I of the Research Diagnostic Criteria for TMD (RDC/TMD). To evaluate the electrical activity of the temporal and masseter muscles in the rest position and during maximum voluntary contraction, a DAB-Bluetooth Instrument (Zebris Medical GmbH, Germany) was used. The analysis of the receiver operating characteristic (ROC) curve gave information about accuracy, cut-off point value, sensitivity and specificity of the normalized sEMG data. Results: The highest diagnostic efficiency of sEMG in terms of identifying subjects with TMD and pain-related TMD was observed for the mean values of temporal and masseter muscle activity as well as the Asymmetry Index of the masseter muscles in a rest position. A moderate degree of EMG accuracy in differentiating between pain-related TMD and non-TMD children was observed for the mean values of masseter muscle activity and the Asymmetry Index of the masseter muscles at rest. Conclusion: An evaluation of electromyography exhibits its diagnostic usability in recognition of patients with pain-related TMD and it could be used as an adjunctive tool in the identification of this disorder. Clinical Trial Registration: This clinical research was registered in the ClinicalTrials.gov database under the number NCT03308266.

Parents' Knowledge, Attitude and Behaviour toward Cleft Lips and Cleft palate in Kencana Hospital, Serang, Banten

INTRODUCTION

Cleft lips (CL) and cleft palate (CP) are common congenital diseases caused by gene mutation in embriology development of the lips and mouth at 4 weeks of gestation. CL and CP can cause several problems such as difficulty in eating, speaking, abnormality in teeth and mouth development and ear iritation. Adequate treatment is needed to improve patients' quality of life.

MATERIAL AND METHOD

This cross sectional study take samples purposively from all parents who joined in cleft charity surgery in Kencana Hospital, Serang, Banten on October 24th 2018. This study identify parents' knowledge, attitude and behaviour towards CL and CP and analyzed the relationship of parents' knowledge and attitude towards CL and CP. Statistical analysis used in this study is Fisher method.

RESULT

Ten patients undergo labioplasty surgery, 1 patient undergo labioplasty revision, 5 patients undergo palatoplasty surgery and 10 patients undergo labioandpalatoplasty surgery. The majority of parents' education background have income < 3,5 million a month 84.6% (22 people), do not have any social insurance 88.5% (23 people) and joined in because of they cannot pay for medical treatment 96,2% (25 people). 6.2% (25 people) have under knowledge, 69.2% (18 people) have good attitude and 84.6% (22 people) have good behaviour toward CL and CP. There is no significant relationship between parents' knowledge and attitude toward CL and CP P value = 1,00 (P > 0,05).

DISCUSSION

Parent's under knowledge is caused by their low educational background and inaccurate information and education provided by medical professional. But, they had a good attitude and behaviour toward CL and CP because they had initiative to look for medical help and treat their children same as other normal one. Although they received inaccurate information and education about cleft disease, all parents looked for medical help and did what they were told by medical professionals.

CONCLUSION

The majority of parents in this study have under knowledge about cleft lips and cleft palate but they are still looking for medical help to treat their children. This charity significantly helps parents whose children have cleft lips, with or without cleft palate, to get treated in that area.

Electromyographic Analysis of Masticatory Muscles in Cleft Lip and Palate Children with Pain-Related Temporomandibular Disorders

Aim

The aim of this study was to assess the electrical activity of temporalis and masseter muscles in children with cleft lip and palate (CLP) and pain-related temporomandibular disorders (TMD-P).

Methods

The sample consisted of 31 CLP patients with a TMD-P (mean age 9.5 ± 1.8 years) and 32 CLP subjects with no TMD (mean age 9.2 ± 1.7 years). The children were assessed for the presence of temporomandibular disorders (TMD) using Axis I of the Research Diagnostic Criteria for TMD (RDC/TMD). Electromyographical (EMG) recordings were performed using a DAB-Bluetooth Instrument (Zebris Medical GmbH, Germany) in the mandibular rest position and during maximum voluntary contraction (MVC).

Results

The rest activity of the temporalis and masseter muscles was significantly higher in TMD-P group compared with non-TMD children. A significant decrease in temporalis muscle activity during MVC was observed in TMD-P patients. There was a significant increase in the Asymmetry Index for temporalis and masseter muscle rest activity in the TMD-P group.

Conclusion

Cleft children diagnosed with TMD-P have altered masticatory muscle activity, and this can affect their muscle function.

Reliability of a Categorical Scale (GOSLON) and a Continuous Scale (10-cm Visual Analog Scale) for Assessing Dental Arch Relationships Using Conventional Plaster and 3D Digital Orthodontic Study Models of Children With Complete Unilateral Cleft Lip and Palate

Objective:

To assess reliability of scoring plaster models and their 3D digital copy of children with complete unilateral cleft lip and palate (CUCLP) using a continuous scale (10-cm visual analog scale [VAS]) and a categorical scale (GOSLON Yardstick).

Design:

Reliability observational study involving 3 trained GOSLON Yardstick assessors blinded to the origin of the models.

Patients:

Models from 35 New Zealand (NZ) and 35 Oslo CUCLP patients were standardized and randomly ordered before rating.

Outcome Measures:

Assessments were undertaken using the GOSLON and the VAS for both model formats. Twenty percent of sample were randomly selected and rescored at the first assessment, and whole sample was rescored 1 week later. Weighted κ was used to assess GOSLON reliability, while correlation was used for the VAS.

Results:

The VAS and GOSLON intra- and inter-rater agreement was similar for both model formats. Repeat measurements on the day have similar intra-rater reliability as repeat measurements at least a week part. There was no significant difference between the 2 model formats, and both the GOSLON and VAS found the NZ models were significantly worse than Oslo.

Conclusions:

A 10-cm VAS is a reliable method to assess dental arch relationships and appears to have good face validity when compared to GOSLON. The VAS allows for statistically robust rankings of the dental arch relationships, although more studies will be required to enable the VAS scores to have greater clinical meaning. The 3D digital models can be used for GOSLON and VAS rankings with a high degree of reliability.

Occlusal, chewing, and tasting characteristics associated with orofacial dysfunctions in children with unilateral cleft lip and palate: a case-control study

OBJECTIVE

The objective of this study is to assess the associations between orofacial dysfunctions with malocclusion, masticatory performance, and taste in children with and without unilateral cleft lip and palate (UCLP).

MATERIAL AND METHODS

A patient-based, matched, case-control study was conducted involving 108 8- to 10-year-old children divided in UCLP and control groups. Orofacial dysfunctions were evaluated using the Nordic Orofacial Test-Screening (NOT-S). Orthodontic treatment need was evaluated using the Goslon Yardstick Index (GYI) and the Index of Orthodontic Treatment Need (IOTN) of patients and controls, respectively. Masticatory performance was assessed using a chewable test material to determine median particle size (X ₅₀) and distribution of particles in different sieves (b value). Taste perception was evaluated using four solutions (sweet, salty, bitter, or acid) in three different concentrations.

RESULTS

More than half of the patients needed orthodontic surgery. UCLP group presented higher median particle size and needed more chewing cycles to comminute the artificial test into particles smaller than the median than those of controls. UCLP group had less perception of salty flavor than controls. There was a positive correlation between b value and NOT-S examination score for patients. In regression analysis, a significant interrelationship was observed between NOT-S examination score and b value.

CONCLUSIONS

In the UCLP patients, masticatory performance was compromised probably as a result of facial asymmetry and speech disturbance; whereas, taste was less perceived only for salty flavor.

CLINICAL RELEVANCE

These findings provide preliminary evidence that mastication and taste are altered in children with UCLP, so these factors must be followed up to ensure oral and general health in growing individuals.

Pattern of clefts and dental anomalies in six-year-old children: a retrospective observational study in western Norway

OBJECTIVES

Clefts of the lip and/or palate (CL/P) are the most common congenital disorders of the head and neck. In Norway, the incidence is 1.9/1000 live births. The aim of this study was to investigate the frequency and distribution of various types of clefts and dental anomalies in patients treated by the cleft lip and palate (CLP) team in Bergen, Norway.

MATERIAL AND METHODS

The material comprised the records of patients 6 years of age, examined by the CLP team in Bergen from spring 1993 to autumn 2012, incomplete records were excluded. The records of 989 patients were analysed, using frequencies and Chi-square test to compare differences in percentages between groups.

RESULTS

The gender distribution was 58.8% male and 41.2% female. Isolated cleft palate (CP) was the most common condition (39.5%). Clefts of the lip, jaw and palate (CLP) constituted (30%) of cases and (30.5%) had isolated cleft lip (CL). The frequencies of agenesis, supernumerary and peg-shaped teeth were (36.5%), (17.8%) and (7.5%), respectively. Over 50% of the study population were diagnosed with one or more malocclusion. Of the CLP patients, 61.4% had Angle Class III occlusion. Statistical analysis disclosed a positive association of agenesis with Class III occlusion (OR =1.8, p≤ 0.001).

CONCLUSIONS

The findings supported the hypothesis that the distribution of dental anomalies and occlusal disorders varied among patients with CL, CP and CLP. In patients with cleft, there is a twofold chance to get Class III malocclusion in the presence of agenesis.

Assessing Angle's malocclusion among cleft lip and/or palate patients in Jammu

OBJECTIVE

The study was conducted to examine the patients with abnormalities of cleft lip and/or palate and its association with different types of malocclusion.

MATERIALS AND METHODS

This descriptive study was done among 168 patients with abnormalities of cleft lip and/or palate. Angle's classification of malocclusion was applied for assessment of occlusion as Class I, Class II, and Class III. The types of oral clefts classification such as cleft lip unilateral and cleft lip bilateral, cleft palate (CP), unilateral cleft lip with palate (UCLP) and bilateral cleft lip with palate (BCLP) was considered. Chi-square test was applied to analyze the data at P < 0.05.

RESULTS

The study showed different categories of clefts patients as cleft lip (81), CP (31), and both cleft lip and palate (53). The occurrence of unilateral cleft lip (44) was maximum among the sample followed by UCLP (39), and bilateral cleft lip (31). Maximum subjects with Class II (10.7%) and Class III (4.9%) malocclusion were seen with unilateral cleft lip deformities. None of the patients with UCLP had Class III malocclusion.

CONCLUSION

Cleft lip was the most commonly observed deformity and high frequency of Class II and III malocclusion was evident. Therefore, patients with such abnormalities should be screened timely.

Prevalence and correlation between TMD based on RDC/TMD diagnoses, oral parafunctions and psychoemotional stress in Polish university students

The aim of the study was to assess the prevalence of temporomandibular disorders (TMD) and oral parafunctions, as well as their correlation with psychoemotional factors in Polish university students. The research was conducted in a group of 456 students (N = 456). The examination form comprised of two parts: survey and clinical examination. The research diagnostic criteria for temporomandibular disorders (RDC/TMD) was used in order to assess TMD. Symptoms of TMD were observed in 246 (54%) students after clinical examination. The largest group involved students with disc displacement (women: 132, 29%; men: 70, 15%). Women (164; 36%) suffered more frequently than men (82; 18%) from problems related to the stomatognathic system (P < 0.05), described themselves as easily excitable and emotionally burdened, and reported symptoms as tightness of the facial and neck muscles (P < 0.05). In 289 (64%) students intraoral symptoms concerning occlusal parafunctions were observed. In 404 (89%) examined students, nonocclusal parafunctions were recorded. A significant correlation between TMD and psychoemotional problems could be detected. TMD symptoms more often concern women. Emotional burden and excitability are factors predisposing muscular disorders.