Myotonic dystrophy (DM) is a neuromuscular disorder caused by an expansion of a CTG repeat sequence on chromosome 19q13. The aim of the present study was to describe the characteristics and prevalence of oral motor dysfunction in a cohort of children and adolescents with DM and to correlate different aspects of oral motor function with the type of DM and sex. Fifty-six individuals with DM (30 males, 26 females; median age 13y 2mo; range 2y 6mo-21y 5mo) were compared with healthy controls. They were divided into four subgroups: severe congenital DM (n=18); mild congenital DM (n=18); childhood DM (n=18); and classical DM (n=2). A speechlanguage pathologist assessed different variables of oral motor function, intelligibility, and lip force. The families used a questionnaire to report on eating difficulties and drooling. All individuals with DM had impaired facial expression. Intelligibility was moderately or severely reduced in 30 patients (60%), excluding six patients without speech. Most had a moderate or severe impairment of lip motility (76.0%), tongue motility (52.2%), and lip force (69.2%), causing deviant production of bilabial and dental consonants. The families reported problems with eating (51.9%) and drooling (37.0%). Oral motor dysfunction was most prominent in congenital DM, and males were more affected than females.Myotonic dystrophy (DM) is a slowly progressive neuromuscular disorder with autosomal dominant inheritance. It is caused by an expansion of a CTG repeat sequence (trinucleotide expansion) on chromosome 19q13. The number of CTG repeats correlates broadly with the overall severity of the disease, but the correlation between the size of the CTG repeat sequence and individual clinical manifestations still needs to be elucidated. 1 DM can be congenital and can appear in childhood or later in life (adult or classical type). The cardinal symptoms are weak muscles, especially in the face, neck, hands, and feet, but smooth muscles are also affected. 2 Myotonia is a common feature in adults with DM but this can also be seen in children. [2][3][4][5] Most individuals with the congenital or childhood type have learning disability* and there are an increased number of children and adolescents with DM who have a neuropsychiatric disorder in comparison with the prevalence in the general population. [4][5][6][7] Newborn infants with the congenital form of DM generally have profound difficulties with sucking and breathing because of neonatal hypotonia. Polyhydramnios during pregnancy, caused by poor fetal swallowing, is often noted. 2,4,5 Adults with DM commonly develop flaccid dysarthria with indistinct articulation and hypernasal speech caused by velopharyngeal impairment. [8][9][10][11] The speech characteristics of children and adolescents with DM have not been described previously in any detail. Although orofacial weakness is a characteristic symptom in congenital and childhood DM, 2,4,5 research into the consequences for feeding in infancy, chewing, swallowing, and speech is very limited. Different as...

Myotonic dystrophy or dystrophia myotonica (DM) is a hereditary neuromuscular multisystem disease with a varying clinical expressivity and severity. The objective of this study was to assess the oral health in children with myotonic dystrophy and to compare it with a control group. Fifty-six DM patients, aged 2.7-18.0 yr, were compared with age- and gender-matched control patients with respect to caries, plaque, and gingivitis. Oral function and signs of temporomandibular dysfunction (TMD) were assessed, and the ability to co-operate in dental treatment was estimated. Questionnaires concerning eating habits, dental care, traumatic injuries to teeth, and orofacial function were also used. The DM patients had significantly more caries, plaque, and gingivitis than did control patients. They had more TMD problems and lower co-operation ability than the healthy control persons. General sedation was frequently needed to carry through dental treatment. DM patients are at risk of caries, gingivitis and TMD problems, and need intensified prophylactic care. Behavior management problems are common.

Ultrasound technique was applied to measure the thickness and examine the internal structure of the masseter muscle in a group of 16 adult patients (nine women and seven men) with myotonic dystrophy (MyD) and 16 healthy individuals matched in age, sex and number of occluding teeth. The masseter thickness was measured bilaterally under both relaxed conditions and during maximal clenching. The error of measurement was found to be small, not exceeding 0.45 mm. The imaging characteristics of the masseter in most of the MyD patients was an obvious atrophy of the muscle with increased echointensity of the intramuscular tissue and loss of the internal structure concerning tendons and fasciae. The mean masseter thickness (+/- SD) in the MyD group was 10.4 (+/- 2.2) mm under relaxed conditions and 11.1 (+/- 2.4) mm during maximal clenching, compared with 13.3 (+/- 2.2) mm and 14.1 (+/- 2.4) mm, respectively, in the healthy group (P < 0.001). In conclusion, our results indicate that, in most of the myotonic dystrophy patients, the masseter muscle is atrophic with obvious signs of degeneration. Ultrasound is a useful method for both qualitative and quantitative evaluation of the condition of the masseter muscle.

The aim of the investigation was to try to explain why patients with myotonic dystrophy (MD) have a high caries prevalence. Seventeen MD patients, 15 of whom had been examined 8 years earlier, and 17 matched, healthy controls participated. In connection with this follow-up examination, the oral sugar clearance was evaluated after chewing a glucose tablet. A paraffin-stimulated whole saliva sample was collected for determination of secretion rate, buffer capacity, and numbers of mutans streptococci and lactobacilli. Dietary score, plaque index, oral muscular coordination, and self-cleaning ability were also recorded. For all factors, the MD patients showed less favorable mean values than the controls; the differences between the groups were statistically significant, except for the bacterial counts and the salivary buffer capacity. Thus, the high caries prevalence in MD patients may be explained by longer oral sugar clearance time, lower salivary secretion rate, higher intake frequency of sugar-containing products, higher plaque index, and less pronounced oral muscular coordination and self-cleaning ability than in healthy individuals.

Young patients with DM1 had already from the beginning a more retrognathic profile and hyperdivergent skeletal aberration with a steep mandibular plane and large intermaxillary angle when compared with healthy individuals. The intermaxillary angle did not decrease during the observation period, contrary to what was observed in healthy individuals.