Find a Registered Dental Hygienist


Knowledge Network

FACT SHEET: Fetal Alcohol Spectrum Disorder (also known as “FASD”; includes “fetal alcohol syndrome [FAS]”, “partial FAS [pFAS]”, “alcohol-related neurodevelopmental disorder [ARND]”, “alcohol-related birth defects [ARBD]”, and “neurobehavioural disorder associated with prenatal alcohol exposure [ND-PAE]”)1

Date of Publication: June 20, 2019

Is the initiation of non-invasive dental hygiene procedures* contra-indicated?

  • No, unless the patient/client displays behavioural signs/symptoms that pose a risk to himself/herself or the dental hygienist during procedures (e.g., extreme restlessness or aggression).

Is medical consult advised?

  • Yes, if undiagnosed2 FASD is suspected.
  • Yes, if poor response to intervention in previously diagnosed FASD is suspected.

Is the initiation of invasive dental hygiene procedures contra-indicated?**

  • No, for most patients/clients.
  • Yes, if the patient/client displays behavioural signs/symptoms that pose a risk to himself/herself or the dental hygienist during procedures (e.g., extreme restlessness or aggression).
  • Yes, if the patient/client has any cardiac condition for which antibiotic prophylaxis is recommended in the guidelines set by the American Heart Association (AHA) unless the dental hygienist has consulted with either the patient/client’s physician, dentist, or registered nurse in the extended class and determined that it is appropriate to proceed if the patient/client has taken the prescribed medication per the AHA guidelines.

Is medical consult advised?

  • See above.

Is medical clearance required?3

  • Yes, for any cardiac condition requiring antibiotic prophylaxis. Medical clearance may also be required for certain co-morbid conditions (e.g., significant seizure risk).

Is antibiotic prophylaxis required?

  • Possibly but not typically, because some patients/clients with FASD have congenital heart disease. AHA antibiotic prophylaxis guidelines for infective endocarditis should be followed for patients/clients with unrepaired cyanotic congenital heart disease (including palliative surgical shunts and conduits) or repaired congenital heart disease with residual defects4 or prosthetic patches/devices within first 6 months of repair procedure.

Is postponing treatment advised?

  • Yes, if the patient/client exhibits behavioural signs/symptoms that may pose a risk during, or cause inability to perform, procedures.
  • Yes, until medical assessment has occurred regarding possible antibiotic prophylaxis in patients/clients with a history of congenital heart disease.
  • Possibly, if there is co-morbid epilepsy (depends on severity and level of control of the disease, including compliance with treatment regimen and presence/absence of oral pathology ― such as tooth fractures ― that may need to be addressed prior to dental hygiene treatment).

Oral management implications

  • Given the dental hygienist’s education on facial features, the hygienist can play an important role in first identifying FASD.
  • The dental hygienist should adequately screen the patient/client with FASD prior to treatment. This includes eliciting information related to behavioural, neurological (including seizure), mental health, and physical manifestations. To optimally accomplish this, the dental hygienist should express a supportive, non-judgmental attitude, which will assist in overcoming reluctance on the part of the patient/client and/or parent/guardian to disclose a history of FASD.
  • Patients/clients with fetal alcohol syndrome have a high prevalence of dental anomalies and speech pathologies that often require early intervention. Other co-morbidities are also common.
  • The patient/client may exhibit behavioural, emotional, and/or physical difficulties that complicate the provision of oral healthcare. These include: aggressive behaviour when upset; impulsiveness; anxious, hostile, and uncooperative behaviour; hyperactivity5; short attention span and distractibility; inability to answer questions appropriately due to speech disorder or brain dysfunction; memory impairment; danger of self-injury from removable prosthetic devices; and motor skills impairment.
  • A calm appointment environment in which stress is minimized is desirable.
  • Management of dry mouth may be indicated for mouth breathing and/or as result of side effects from medications used to treat hyperactivity or attention deficit or epilepsy.
  • Nutritional counseling and caries risk assessments may positively influence the patient/client’s oral health, particularly if there are undesirable eating patterns (including snacking on cariogenic foods and eating between meals).
  • Manual dexterity should be evaluated, because difficulties in handwriting have been reported in persons with FASD, which may also affect their ability to brush and floss properly. Personalized self-care instruction with modifications is warranted to optimize to plaque control.

Oral manifestations

  • In FAS, distinctive orofacial characteristics include: smooth, indistinct philtrum; thin upper lip and vermilion border; and incomplete development of midface. Mandibular micrognathia and maxillary hypoplasia contribute to collapse of the midface.
  • Other orofacial abnormalities in FAS may include: microdontia with defective enamel; cleft lip; cleft palate; malocclusions; and poor tongue thrusting.
  • Mouth breathing resulting from orofacial deformities can lead to dry mouth, as well as contribute to malocclusions with increased or decreased overjet, anterior and posterior crossbite, open bite, and contact point displacement. The net effect is an increase in the long-term risk of caries, occlusal trauma, and periodontal diseases.
  • Dental eruption may be slightly delayed.
  • Labial inclination of the upper incisors may result from a high rate of non-nutritive sucking (thumb or tongue suction).
  • Temporomandibular joint (TMJ) disorders occur at elevated rates.
  • Sleep apnea may be related to retraction of the midface.
  • Poor oral hygiene related to behavioural and emotional issues may manifest as gingivitis, spontaneous gingival bleeding, plaque, and decay.
  • Gingival overgrowth may be present if the patient/client is taking the anticonvulsant phenytoin for seizure control.

Related signs and symptoms

  • A pregnant woman with active alcohol dependence/addiction is at elevated risk for delivering a child with FASD.6 This umbrella term describes persons who experience disability as a result of prenatal alcohol exposure, and it encompasses a range of conditions which together constitute the leading cause of developmental disability in Canada. While preventable (i.e., by no alcohol consumption during pregnancy), these incurable conditions are associated with damage to the central nervous system.
  • FASD is estimated to occur in Canada at the rate of 9 per 1,000 births (i.e., just under 1% of births), although this may be an underestimation of the true burden of illness.7
  • Fetal Alcohol Syndrome
    • FAS is the most serious end of the FASD spectrum, and fetal death is the most extreme outcome from consuming alcohol during pregnancy.
    • Failure to thrive, growth impairment (including microcephaly and short stature), and intellectual and developmental disabilities occur.
    • Features associated with FAS include: abnormal facial characteristics (including low forehead with frontal bossing (due to maxillary retrusion); low nasal bridge; short, “snub” nose; short palpebral fissures8; epicanthal folds9; orbital hypertelorism [widely spaced eyes]; ear anomalies [including low set ears and vestibular dysfunction]); nail dysplasia; learning disabilities; behavioural challenges; speech impairments; hyperactivity; decreased muscle tone contributing to poor motor skills and coordination; and problem-solving and memory deficits.
    • The facial abnormalities that are present at birth tend to become less apparent with growth. However, degree of intellectual disability is correlated with the severity of craniofacial anomalies.
  • Partial fetal alcohol syndrome
    • In contradistinction to FAS, there are fewer facial abnormalities and no growth impairment in the presence of alcohol-related brain injury.
  • Alcohol-related neurodevelopmental disorder
    • In contradistinction to pFAS, there are no facial abnormalities as well as no growth impairment in the presence of alcohol‑related brain injury. However, persons with ARND may have intellectual disabilities and problems with learning and behaviour.
  • Alcohol-related birth defects
    • Birth defects include: congenital heart disease (including atrial and ventricular septal defects); malformations of the kidneys, liver, and bones; impairments of vision and hearing; and reduced immune function.
    • ARBD is rarely seen alone but rather as a secondary disorder accompanying other FASD conditions (particularly FAS).
  • Neurobehavioural disorder associated with prenatal alcohol exposure
    • A child or youth with ND-PAE has problems in 3 areas: thinking and memory; behaviour; and day-to-day living.
  • Patients/clients affected by FASD often lead chaotic lives, including difficulties in family and social relationships, school, employment, mental health, and the legal system. Depression, anxiety, conduct disorder, attention deficit and hyperactivity disorder (ADHD), and alcohol and substance misuse occur at elevated rates.
  • Seizures occur in 3% to 21% of children with FASD.
  • Diabetes and hypertension may occur at elevated rates.
  • Persons with FASD may develop their own alcohol and substance-abuse problems.

References and sources of more detailed information

Date: November 13, 2018
Revised: April 14, 2023


1 Prior to 1996, the term “fetal alcohol effects” (FAE) was used to described intellectual disabilities and problems with behaviour and learning in a person whose mother consumed alcohol during pregnancy. In that year, the Institute of Medicine (IOM) replaced FAE with the terms ARND and ARBD.
2 In addition to history of maternal consumption of alcohol during pregnancy, diagnosis of FASD involves characteristic findings on physical (particularly facial) and neurodevelopmental assessments.
3 Although some patients/clients with FASD may have defects in their immune system, these are not typically significant enough to warrant medical clearance.
4 Residual defects include persisting leaks or abnormal flow at or adjacent to a prosthetic patch or prosthetic device.
5 Inability to keep a stable position in the dental chair may lead to a requirement for general anesthesia for some oral healthcare procedures.
6 The severity of FASD features depends on a variety of factors, including timing of alcohol exposure during fetal development (e.g., during early first trimester for distinctive facial features of FAS) and amount and duration of alcohol consumption by the mother. The risk of FAS in offspring of woman who continually drink heavily (5 or more drinks per day) during pregnancy is high. However, some damage — not necessarily full FAS — can occur with a single binge (5 or more drinks). There is no safe level of alcohol use during pregnancy — ethanol is a known teratogen.
7 A 2018 study by the Centre for Addiction and Mental Health indicated that 2% to 3% of children in the Greater Toronto Area had FASD. The 2019 Canadian Health Survey of Children and Youth (aged 1 to 17 years) found a prevalence of 1/1,000 (0.1%) amongst those living in private dwellings; Canadian children and youth who identified as Indigenous and lived off reserve had a significantly higher prevalence of FASD than those who did not identify as Indigenous (1.2% versus 0.1%). Diagnosis of FASD relies on medical assessment (including signs/symptoms, sentinel facial features, and maternal alcohol history) and neurodevelopmental assessment.
8 A palpebral fissure is the elliptical space between the medial and lateral canthi (corners) of the upper and lower eyelids.
9 An epicanthal fold is a skin fold of the upper eyelid covering the medial canthus (inner corner) of the eye.

* Includes oral hygiene instruction, fitting a mouth guard, taking an impression, etc.
** Ontario Regulation 501/07 made under the Dental Hygiene Act, 1991. Invasive dental hygiene procedures are scaling teeth and root planing, including curetting surrounding tissue.