Occlusal traits and longitudinal dental changes in children and adolescents with congenital or childhood onset myotonic dystrophy.

BACKGROUND/OBJECTIVES: This research aimed to study the malocclusions of children and adolescents with myotonic dystrophy type 1 (DM1), in respect to healthy individuals, and trace the occlusal changes that occurred in these individuals during growth. MATERIALS/METHODS: Thirty-six dental casts, from children and adolescents with DM1 living in western and southern Sweden, were compared with a control group of 50 healthy individuals. To identify potential changes in occlusal traits, 26 casts were assessed and followed-up over a median time of 9 years. Independent samples t-tests were used to compare the two groups and their changes over time. Paired samples t-tests tested changes over time within each group (P < 0.05). RESULTS: DM1 patients had a higher prevalence of anterior open bite, posterior crossbite, and Class III malocclusions. When compared to controls, patients presented smaller upper and lower intermolar as well as intercanine widths. In both groups, the individuals revealed longitudinal changes with a decrease in both upper and lower arch lengths and an increase on the palatal vault height. During the follow-up period, the prevalence of malocclusions remained almost the same, only significantly differing regarding the changes that occurred between groups referred to the upper intermolar width, which decreased among DM1 patients. CONCLUSIONS/IMPLICATIONS: In comparison to healthy controls, children and adolescents with DM1 have shown already at an early age a higher prevalence of both anterior open bite and posterior crossbite. These occlusal traits did not change with time apart from the upper narrow intermolar width, which further decreased with time.

Speech characteristics in the congenital and childhood-onset forms of myotonic dystrophy type 1.

BACKGROUND: Myotonic dystrophy type 1 (DM1) is a slowly progressive multi-systemic disease with an autosomal-dominant inheritance caused by a mutation on chromosome 19 (19q13.3). AIMS: To explore speech characteristics in a group of individuals with the congenital and childhood-onset forms of DM1 in terms of intelligibility, speech-sound production, nasality and compensatory articulation. A further aim was to analyse whether speech characteristics were correlated to subforms of DM1 and if speech outcome could be related to muscle strength. METHODS & PROCEDURES: Fifty native Swedish speakers (7-29 years old) with the congenital and childhood-onset forms of DM1 and 13 healthy controls participated in the study. The intelligibility of spontaneous speech, speech-sound production - single-word and sentence repetition - including percentage consonants correct (PCC) and compensatory articulation, were evaluated by speech-language pathologists from video recordings. A nasometer and lip-force meter were used for objective evaluations of nasality and orofacial strength. OUTCOMES & RESULTS: In severe (n = 9) and mild congenital DM1 (n = 13), all participants had impaired intelligibility to some degree, while this applied to 79% of those with childhood DM1 (n = 28). PCC for bilabials were 53.9% in severe congenital DM1, 57.4% in mild congenital DM1 and 85.3% in childhood DM1; the corresponding results for dentals were 69.3%, 59.2% and 87.3%. Bilabials were most often compensated for with interdental or labiodental articulation. Dentals were substituted with interdental articulation. Velars were seldom affected. The mean nasalance score was high in the study group compared with controls and with normative data and the majority had weak lips. Maximum lip force, as well as the mean nasalance score, correlated significantly with the intelligibility score. CONCLUSIONS & IMPLICATIONS: The deviant production of bilabial consonants, interdental articulation and hypernasal speech are characteristic features of dysarthria in congenital and childhood DM1. Dysarthria is more frequent and more severe in congenital DM1 compared with childhood DM1. Most individuals with congenital DM1 and childhood-onset DM1 will need speech therapy from a young age. For some children with incomprehensible speech or severe neurodevelopmental disorders, alternative and augmentative ways of communication will be part of the treatment.

Oral hygiene aspects in a study of children and young adults with the congenital and childhood forms of myotonic dystrophy type 1.

The primary aim was to study the interaction between oral hygiene, oral care, saliva production, and oral motor function in individuals with myotonic dystrophy type 1 (DM1). A secondary aim was to study how oral hygiene, oral care, and saliva flow rate are affected by gender, age, and subgroup of DM1 in this study population. The study comprised 52 individuals, seven to 29 years of age, divided into two subgroups of DM1, the congenital (N = 24) and childhood-onset forms (N = 28). A combined dental and oral motor examination was performed and the participants or caregivers answered a questionnaire with questions about general health and disabilities, medication, dental care, and oral health. Sixteen individuals with a plaque-, gingivitis-, or calculus-index score of 5-6 were considered to have poor oral hygiene. There were no significant differences between subgroups (age, gender, or form of DM1) in terms of the occurrence of calculus, gingivitis, plaque, or saliva flow rate. The mean value of the unstimulated whole saliva flow rate was 0.7(±0.44) mL/min. An open mouth at rest and oral motor dysfunction were frequent findings. The majority of Swedish children and young adults with the congenital or childhood form of DM1 have fair or poor oral hygiene, with a high occurrence of plaque and gingivitis. As a group, individuals with DM1 and poor oral hygiene have a higher frequency of caries and they report less satisfaction with their oral care at home and the quality of dental care received compared with those with good oral hygiene.