Prader-Willi syndrome ( a very rare genetic disorder, in which seven genes on chromosome 15 are missing or unexpressed .They usually have slow mental development, small hands and feet as compared to the body, almond shaped eyes, and skeletal abnormalities, such as a narrow bifrontal skull. Symptoms also include floppy infants
Williams syndrome (a rare neurodevelopmental disorder caused by a deletion of about 26 genes from the long arm of chromosome 7. It is characterized by a distinctive, "elfin" facial appearance, along with a low nasal bridge; mental retardation and cardiovascular problems, such as supravalvular aortic stenosis .
History taking History of birth trauma, asphyxia, or infection may predispose to central hypotonia. It is important to identify whether the hypotonia was present at birth (congenital) or later on. The distinction between a static course (e.g., due to brain insults) or progressive course (due to dystrophies) is critical. Static causes usually results in slow improvements, while progressive causes results in relentless deterioration.
Abnormal head size could suggest a central cause.
Bruising could suggest an acute traumatic etiology.
By inspection, Central hypotonia is usually associated with abnormal primitive
reflex in response to handling (3).
Some diagnostic tests may also be used. Computerized tomography scan (CT scan)
Magnetic resonance imaging (MRI )
Electroencephalogram (EEG): a test that measures the electrical activity in the brain.
Karyotype: a test that performs a chromosomal analysis from a blood test, used to determine whether the hypotonia is the result of a genetic disorder
Muscle biopsy: a sample of muscle tissue removed and examined under a microscope.
Once the correct diagnosis is confirmed, the cause is treated first, followed by symptomatic and supportive therapy for the hypotonia.
Physical therapy can improve fine motor control and overall body strength.
Occupational and speech-language therapy can help breathing, speech, and swallowing difficulties.
Therapy for infants and young children may also include sensory stimulation programs.
Central hypotonia due to static usually improves with time. The prognosis is worst for hypotonia of progressive central disorders.
Children with mild hypotonia may not experience developmental delay, although some children acquire gross motor skills (sitting, walking, running, jumping) more slowly than most. Most hypotonic children eventually improve with therapy and time. Some children are more severely affected, requiring walkers and wheelchairs and other adaptive and assistive equipment.
You must take in consideration that the neuromuscular problems can affect the oral health in several ways.
Malocclusion, hypotonia of the orofacial muscles result in forward tongue posturing, class II malocclusion, poor swallow reflex and mouth breathing (4).
The higher prevalence of class II malocclusion with protruded incisors increases the risk of dental trauma (4).
Sialorrhea (drooling), because of the neuromuscular problems the patient is not able to swallow the saliva .which result in infection, dehydration and perioral inflammation. They also, tend to build up extensive calculus deposits.
The higher calculus deposit and plaque index together with mouth breathing will help to increase the caries rate in these patients (5).
During dental treatment;
Determine the best position for your patient in the dental chair and the safest way to move his or her body, especially the head and neck. Talk with the physician about ways to protect the spinal cord. Use pillows to stabilize your patient and make him or her more comfortable.
In a study done to compare various management techniques in patients with CP during their dental treatment they found that he use of assistive stabilization reduces the number of patient referred to general anesthesia(6).
Maintain a clear path for movement throughout the treatment setting.
REFERANCE, Mohammed M.S. Jan, The hypotonic infant: Clinical approach. J of Pediatric Neurology 5 (2007), 181–187.
Amirsalari S, Kavehmanesh Z, Khalili Matinzadeh Z, Afsharpayman S, Torkaman M, Javadipour M, et al. Hypotonia in infants and young children: An etiological analysis. Pak J Med Sci 2008; 24(5):744-47.