Orthodontic treatment of a case of Becker muscular dystrophy

Abstract

Becker muscular dystrophy, similar to Duchenne muscular dystrophy, is a X-chromosomal linked anomaly characterized by progressive muscle wasting and weakness. Duchenne-type is known to have severe openbite with a steep mandibular plane, but there are no studies that describe the occlusal and skeletal patterns of the Becker-type. Here, we report the orthodontic treatment of a Becker muscular dystrophy patient. In the correction of his severe skeletal open bite general anesthesia or orthognathic surgery was not an option. Multiloop edgewise archwires were employed for orthodontic treatment. After 3 years and 8 months the open bite was corrected. During the retention period contact between the anterior teeth was maintained 8 months after active treatment despite a marked relapse tendency.

Botulinum neurotoxin type A in the masseter muscle: Effects on incisor eruption in rabbits

“…44 We speculate that the loss of occlusal force, rather than the loss of attrition, would be the predominant influence in the clinical situation, and thus would expect patients treated with BoNT/A to exhibit excessive eruption as in other types of muscle weakness rather than retarded eruption as exhibited by the rabbits. 20–22 This scenario is plausible but depends on 2 assumptions: (1) that slower attrition was the cause of slower eruption in the rabbits, and (2) that attrition would be a negligible factor for human eruption. If these assumptions are false, then BoNT/A could conceivably retard eruption in patients as well as rabbits.…”

“…When an opposing tooth is removed experimentally 12,15–18 or clinically, 19 eruption speeds up, and overeruption occurs. Muscle weakness in humans 20–22 and muscle resection in rats 23 have the same effect. Because BoNT/A paralysis also causes muscle weakness, it can lead to supraeruption.…”

The effects of muscular dystrophy on the craniofacial shape of Mus musculus

“…Although it is widely known that muscular dystrophy alters bone growth (e.g. Suda et al. 2004; Matsuyuki et al.…”

“…In humans, MD is correlated with cranial skeletal abnormalities (Matsuyuki et al. 2006) and interferes with orthodontic treatment (Suda et al. 2004).…”

Orthodontic treatment in a patient with unilateral open-bite and Becker muscular dystrophy. A 5-year follow-up

“…This patient has similar characteristics to subjects with Duchenne dystrophy, namely: inclined mandibular plane, counterclockwise rotation of the mandible and increased gonial angle. 10 …”