This course was published in the December 2018 issue and expires December 2021. The author has no commercial conflicts of interest to disclose. This 2 credit hour self-study activity is electronically mediated.
After reading this course, the participant should be able to:
- Discuss the prevalence, incidence and ramifications of spina bifida.
- Define the risks and protective factors associated with the development of this neural tube defect.
- Differentiate between various types of spina bifida, and list common impairments and complications associated with this condition.
- Identify oral health care considerations for this patient population.
Spina bifida is a neurogenetic disorder with a complex etiology that involves genetic and environmental factors.1 It is part of a larger group of congenital birth defects termed neural tube defects. These defects affect various parts of the central nervous system, such as the brain, spine and spinal column.2 The most common neural tube defect, spina bifida is a largely preventable, noncommunicable, and permanently disabling congenital condition that results in the incomplete development of the brain, spinal cord and/or meninges.3 Health disparities continue to exist for individuals with neural tube defects in both racial/ethnic and sex distribution. Hispanics are at higher risk than non-Hispanics,4 and non-Hispanic whites are at higher risk than non-Hispanic blacks. In all racial and ethnic communities, women are at higher risk than men.4
The U.S. Centers for Disease Control and Prevention’s (CDC) National Spina Bifida Patient Registry and Surveillance System estimates the national prevalence of this condition at 166,000 individuals.4 Researchers estimate the national annual incidence of spina bifida to be approximately 1500 live births.4
There are significant social and economic costs for individuals with this neural tube defect. Multiple studies have tracked national expenditure trends in populations with spina bifida. Affected children have an approximate 13-fold increase in health care expenditures compared to children without neural tube defects, whereas adults with spina bifida experienced a threefold to sixfold increase in health care expenditures.5 The medical care and surgical costs for all affected individuals exceed $200 million annually, with the lifetime cost of care for each child born with spina bifida estimated at more than half a million dollars.5
Diagnostic screening begins in the first trimester of pregnancy at 28 days of gestation. To detect spina bifida, the mother’s maternal serum alpha-fetoprotein levels can be measured, a thorough ultrasound examination can be performed, or an amniocentesis can be conducted.3
Multiple risk factors are associated with the development of spina bifida: familial history of neural tube defects, mother’s consumption of anticonvulsant medication, and mother’s systemic health status, such as presence of obesity and/or diabetes mellitus type 2.4 Clinical and public health studies have indicated the appropriate intake of folic acid is the most significant preventive method for reducing the risk of this condition.3 Folic acid is a water-soluble B-9 vitamin that is available in supplements or through dietary sources, including asparagus, avocado, beans, milk, orange juice, salmon, soybeans and spinach.6 In 1992, the U.S. Public Health Service published the mean recommended dosage to minimize risk for pregnancies with spina bifida at 0.4 mg (400 mcg).7 The CDC estimates that approximately 50% of all pregnancies in the United States are unplanned; therefore, it is important for all women of childbearing age to take the recommended dosage of folic acid daily.4 Women at increased risk, such as mothers with affected children, typically require a tenfold prescriptive dosage of 4 mg folic acid per day at least one to three months before conception, and continuing through the first trimester of pregnancy to minimize risk for neural tube defects.8
Research has been conducted on the polymorphic mutational impact of the methylenetetrahydrofolate reductase (MTHFR) gene in the incidence of spina bifida.9 This mutation modifies the innate ability of the subsequent MTHFR enzyme to process folate in the body.9 Further research is needed on the role of the MTHFR gene and enzyme on the incidence of neural tube defects.
There are four types of spina bifida: occulta, closed neural tube defect, meningocele and myelomeningocele, with the closed neural tube defect being the most rare.3,4 Occulta is the mildest and most common form, and is a condition in which the vertebrae are malformed.3 Present in approximately 10% to 20% of the affected population, occulta rarely causes disability and is typically asymptomatic.3 Closed neural tube defects consist of a diverse group of vertebral defects marked by malformation of fat, bone or membranes, and can result in neurogenic bowel and bladder.3
Meningocele and myelomeningocele manifest with a physiological protrusion through an abnormal vertebral opening. In myelomeningocele, however, the spinal cord and neural elements in the physiological protrusion are exposed and vulnerable to symptomatic paralysis.3 Table 1 outlines the commonly associated impairments and clinical considerations in this patient population.10
Hydrocephalus, or fluid in the brain, is caused by excessive accumulation of cerebral spinal fluid (CSF), resulting in increased pressure in the ventricular environment.11 Approximately 80% of patients with spina bifida experience hydrocephalus.6 An excessive accumulation of CSF presents as an abnormally rapid increase in cranial circumference or an unusually large head.12 The abnormal widening of the craniofacial structure creates potentially harmful pressure on the cranial meninges, increasing risk for abnormal gait, altered coordination, visual impairment, developmental delay and/or convulsive seizures.11 The typical medical protocol for hydrocephalus is the surgical placement of a biocompatible shunt to redirect excessive cerebral fluid from the ventricles into alternative vital organs for systemic excretion.10 Artificial shunts placed for the management of hydrocephalus include ventriculoperitoneal (VP) shunts, ventriculoatrial shunts, ventriculopleural shunts or ventriculocholecyst shunts.12 The VP shunt is the most common.
The American Academy of Pediatric Dentistry and American Heart Association recognize that patients with certain types of complex medical conditions face increased risk for bacteremia-induced infections, including infective endocarditis.13 Patients with shunted hydrocephalus who have a ventriculoatrial shunt, ventriculocardiac shunt or ventriculovenus shunt are at a significantly increased risk for bacteremia-induced infections. As such, they should be prescribed prophylactic antibiotic premedication for invasive dental procedures, as should those at risk for infective endocarditis.13 Oral health care procedures that engage in “manipulation of gingival tissues, periapical regions of teeth, or perforation of oral mucosa” are invasive and may increase the risk for infective endocarditis.13 The use of prophylactic antibiotic premedication decreases — but does not eliminate — the risk for bacterial-induced infections.13 Clinicians should be selective in prescribing antibiotics based on the individual needs of the patient to minimize risk for antibiotic resistance and allergic sensitization.
Patients with impaired autonomic nerve function can manifest with neurogenic bowel and bladder.11 The permanent nerve damage secondary to spina bifida can result in interrupted voluntary communication between the sphincter muscles, spinal column and bowel/bladder function.14 Unfortunately, these patients experience both frequent urinary tract infections and/or frequent fecal impactions. The typical medical management of neurogenic bowel and bladder includes intermittent catheterization, urinary diversion (such as vesicostomy or bladder augmentation), and pharmaceutical interventions.4
There are multiple oral health considerations for populations affected with neurogenic bowel and bladder, including attentiveness to scheduling appointments, provider sensitivity to patients’ needs to use the restroom, and xerostomia management.14 Individuals with neurogenic bowel and bladder should be encouraged to use the restroom before the appointment, and clinicians should suggest frequent restroom breaks during appointments.14 Oral health professionals should suggest methods to mitigate decreased salivary flow, such as using saliva substitutes, oral lubricants, or over-the-counter, glycerin-based mouthrinses and toothpastes with a neutral pH.14 Patients with xerostomia are also at an increased risk for dental caries, and therefore need close monitoring and, if indicated, topical fluoride therapy.14
Some patients with spina bifida also manifest with the Arnold-Chiari II malformation complex. This presents as an inferior migration of the cerebellum directed proximally toward the foramen magnum; thus, the cerebellum’s depth of protrusion through the foramen magnum categorizes the stage of Arnold-Chiari malformation complex.3 Radiologists can detect the depth of the malformation through magnetic resonance imaging or computed tomography. The second stage of the complex, known as Arnold-Chiari II malformation, occurs when the cerebellar tonsils herniate through the foramen magnum.3 Approximately one in every 1000 live births and one-third of patients with myelomeningocele have Arnold-Chiari II malformation.3,10 Patients can be asymptomatic; therefore, surgical intervention remains deferred until the individual is symptomatic.3 If the patient is symptomatic, a surgical posterior fossa decompression intervention will alleviate pressure at the compression site.3 The common signs and symptoms of Arnold-Chiari II malformation include abnormal gait, altered coordination, irregular respirations, dysphagia, increased aspiration risk, hypersensitive gag reflex, and hypotonia in the arms.6 The development of symptoms varies on the typology and severity of the spina bifida.10
Oral health care implications for individuals with Arnold-Chiari II malformation include preliminary evaluation of a patient’s gait and coordination to assess increased risk for orofacial trauma secondary to falling.14 Patients with Arnold-Chiari II malformation should be positioned upright to minimize concerns with airway obstruction and dysphagia.14 Furthermore, oral health professionals should have extra personnel to assist with suctioning during procedures that use water to minimize the risk of aspiration.14 Clinicians can employ alternative approaches to provide individualized care to patients with special health care needs. For example, if patients experience dysphagia and are at increased risk for aspiration, the dental team can alternate between wet and dry gauzes to cleanse the oral cavity during procedures, rather than using the air/water syringe and suctioning with the saliva ejector.
Many patients with spina bifida have orthopedic concerns, such as clubfoot, dislocated hips, spinal dysplasia and atypical musculoskeletal contractures.6 An estimated 90% of patients with a neural tube defect experience musculoskeletal deformities, including scoliosis, kyphosis or kyphoscoliosis.4 Patients with significant abnormal spinal curvatures undergo surgical rodding procedures that attempt to align the spinal column to a near-normal curvature.14 Some orthopedic surgeons require patients to obtain medical clearances from other clinicians — including the patient’s oral health professional — prior to spinal instrumentation. As such, patients who are candidates for spinal surgery should complete oral health care treatment as soon as possible.14 Dental teams should also maintain communication with the patient and his or her orthopedic surgeon regarding the medical necessity for prophylactic antibiotic premedication for routine and invasive dental procedures post-spinal instrumentation.14
In addition, this patient population is at increased risk for orofacial musculoskeletal concerns, including Angles Class II malocclusions.15 Individuals with malocclusions and crowding have difficulty maintaining adequate oral hygiene and are at an increased risk for developing caries and periodontal disease.15 Those with complex malocclusions may wish to see an orthodontist for therapeutic realignment. Dental providers should help patients minimize their incidence of oral disease by stressing oral hygiene education, increasing preventive dental hygiene visits, placing sealants, frequently applying topical fluoride, and providing referrals to specialists, as necessary.
In addition, affected individuals are at increased risk for a compromised vertebral column; thus, they often experience a permanent altered sensory function.4 Most patients with spina bifida are limited in ambulation and are likely to use assistive devices, such as wheelchairs.14 There are multiple oral health care considerations for patients with limited ambulation and insensate skin. Clinicians should evaluate if the patient, based on comfort and safety, should remain in the wheelchair or transfer to the dental chair for treatment. If the patient remains in the wheelchair, dental teams should embrace adaptive ergonomics to complete the necessary treatment. Alternatively, if a patient transfer scenario is indicated, clinicians should ensure the patient’s receiving platform is at a lower height than the initial platform to minimize risk for patient injury. For example, if a patient transfer is from a wheelchair to the dental chair, the team should lower the dental chair so the transfer is from a higher to lower plane. Conversely, if the transfer is from the dental chair to a wheelchair, the clinician should raise the dental chair slightly so the transfer is from a higher to lower plane. Additional resources, such as extra personnel and patient transfer boards, can assist during transfers.
Patients with impaired sensory function are at increased risk for developing sores, calluses, blisters and bruises. Due to localized spatial areas of insensate skin, individuals with spina bifida are likely to be unaware of their pressure-based wounds.4 Affected individuals can benefit from the use of an intermediary device placed between the patient and the firm dental chair, such as a soft beanbag (Figure 1). A beanbag adapts to the musculoskeletal structure and redistributes bodily pressures. Patients placed on soft beanbags are seated on adaptive and more secure structures, reducing their risk for pressure wounds.14 In addition, dental teams should ideally schedule short appointments to minimize these concerns.
Compared to the general population, patients with spina bifida are at increased risk of latex sensitivity.4 When exposed to latex, an estimated 70% of this patient group exhibits physiological symptoms, including pruritus, erythematous skin, itchy/watery eyes, dyspnea, wheezing and slurred speech.16 The exact etiology for latex sensitivity in patients with spina bifida is idiopathic; however, many sources trace it to frequent exposures during postnatal medical and surgical interventions.17 Studies have also demonstrated that latex sensitivities are associated with allergic reactions to bananas, strawberries and kiwi.18 Many health care facilities have transitioned to nonlatex products to mitigate concerns with sensitivity. Oral health professionals should realize that many dental products may contain latex, including, but not limited to, adhesive bandages, blood pressure cuffs, personal protective equipment, nitrous oxide reservoir bags, orthodontic bands/elastics, rubber cup polishers, dental dams and saliva ejectors.18 An adequate supply of nonlatex alternatives for commonly used armamentarium should be maintained. Early morning appointments are ideal for patients with latex sensitivity to minimize aerosol exposure.18
Patients with special health care needs, such as spina bifida, are a particularly vulnerable and underserved population.19 Dental professionals are valuable members of an interdisciplinary health care team dedicated to improving the overall health of these patients. Spina bifida is a complex neural tube defect with multiple associated impairments and considerations. As such, proactive clinicians should ensure their teams are educated and clinically adaptive to the individual needs of these patients.
- Fletcher JM, Brei TJ. Introduction: spina bifida — a multidisciplinary perspective. Dev Disabil Res Rev. 2010;16:1–5.
- Medline Plus. Neural Tube Defects. Available at: nlm.nih.gov/medlineplus/neuraltubedefects.html. Accessed October 25, 2018.
- National Institute of Neurological Disorders and Stroke. Spina Bifida Fact Sheet. Available at: ninds.nih.gov/Disorders/Patient-Caregiver-Education/Fact-Sheets/Spina-Bifida-Fact-Sheet. Accessed October 25, 2018.
- U.S. Centers for Disease Control and Prevention. Spina Bifida. Available at: https://www.cdc.gov/ncbddd/spina bifida/index.html. Accessed October 25, 2018.
- Ouyang L, Grosse S, Armour B, Waitzman N. Health care expenditures of children and adults with spina bifida in a privately insured U.S. population. Birth Defects Res A Clin Mol Teratol. 2007;79:552–528.
- Spina Bifida Association. Overview. Available at: spinabifidaassociation.org. Accessed October 25, 2018.
- Recommendations for the Use of Folic Acid to Reduce the Number of Cases of Spina Bifida and Other Neural Tube Defects. MMWR Recomm Rep. 1992;41(RR-14):1–7.
- Folic acid for the prevention of neural tube defects. American Academy of Pediatrics. Committee on Genetics. Pediatrics. 1999;104:325–327.
- U.S. National Library of Medicine. MTHFR Gene. Available at: ghr.nlm.nih.gov/gene/MTHFR. Accessed October 25, 2018.
- Kabani F, Anderson M. Treating children with spina bifida. Dimensions of Dental Hygiene. 2012;10(4):52–57.
- March of Dimes. Spina Bifida. Available at: marchofdimes.org/baby/spina-bifida.aspx#. Accessed October 25, 2018.
- Mayo Clinic. Diseases and Conditions Spina Bifida. Available at: mayoclinic.org/diseases-conditions/spina-bifida/basics/definition/CON-20035356?=1&p=1. Accessed October 25, 2018.
- American Academy on Pediatric Dentistry Clinical Affairs Committee.; American Academy on Pediatric Dentistry Council on Clinical Affairs. Guideline on antibiotic prophylaxis for dental patients at risk for infection. Pediatr Dent. 2008–2009;30(Suppl 7):215–218.
- Kabani F. Special care for special needs populations: spina bifida. Presented at Collin County Dental Hygiene Society; October 24, 2015; McKinney, Texas.
- McGuire S. Presentation and Management of Patients at Texas Scottish Rite Hospital for Children: Spina Bifida. Presented at Special Care Dentistry Conference; April 20, 2013; New Orleans.
- American Academy of Allergy, Asthma & Immunology. Latex Allergy. Available at: aaaai.org/conditions-and-treatments/allergies/latex-allergy.aspx. Accessed October 25, 2018.
- American Latex Allergy Association. AANA Latex Protocol. Available at: latexallergyresources.org/articles/aana-latex-protocol. Accessed October 25, 2018.
- Spina Bifida Association. Latex in the Hospital Environment. Available at: spinabifidaassociation.org/project/latex-hospital. Accessed October 25, 2018.
- Lo A, Polsek D, Sidhu S. Estimating the burden of neural tube defects in low-and middle-income countries. J Glob Health. 2014;4:010402.
Featured image by WOLFGANG MORODER, CREATIVE COMMONS ATTRIBUTION-SHARE ALIKE 3.0 UNPORTED LICENSE
From Decisions in Dentistry. December 2018;4(12):40—43.