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FACT SHEET: Autism (also known as “autism spectrum disorder” [ASD]; formerly classified into subtypes including “autistic disorder” (also known as‘mindblindedness’), “Asperger syndrome”, “childhood disintegrative disorder”, “pervasive development disorder not otherwise specified”, and “Rett syndrome1”)

Date of Publication: January 31, 2019

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

  • No, unless the patient/client displays or has a history2 of behaviour3 that poses risk to himself/herself or the dental hygienist during procedures.

Is medical consult advised?  

  • No, if autism has been previously diagnosed and the patient/client is responding well to intervention. 
  • Yes, if developmental delay and/or autism is newly suspected or poor response to intervention in previously diagnosed autism is suspected.
  • Yes, if severe xerostomia is suspected to be related to medication used to manage a co-morbidity (which may improve if an alternative drug is a consideration).

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

  • No, unless the patient/client displays or has a history4 of behaviour5 that poses risk to himself/herself or the dental hygienist during procedures.

Is medical consult advised? 

  • See above.

Is medical clearance required? 

  • No, unless severe leukopenia (i.e., reduced white blood cell count, and hence immunosuppression) is suspected with antidepressant or antipsychotic medication use. [This would be a rare situation in the dental hygiene office setting.]

Is antibiotic prophylaxis required?  

  • No (in the absence of immunosuppression).

Is postponing treatment advised?

  • No, unless:
    • medical clearance is pending regarding possible immunosuppression associated with antidepressant or antipsychotic use; or 
    • the patient/client exhibits behaviour that may pose a risk during, or cause inability to perform, procedures, in which case intervention to mitigate risk is first needed.

Oral management implications

  • Communication and behavioural challenges are the major impediments in providing oral care. 
  • Patients/clients may not react appropriately to common verbal and social cues, such as tone of voice or smile. Further complicating dental/dental hygiene care may be repetitive behaviours, obsessive routines, unpredictable body movements, and self-injurious behaviour. Most patients/clients with mild to moderate autism, however, can be treated successfully in the general practice dental hygiene setting. 
  • In order to address communication problems and mental functioning, the oral healthcare provider should speak with the parent or caregiver to learn how best to communicate with the patient/client. A “tell-show-do” approach often is helpful; this means explaining each procedure before it occurs, showing what has been explained (e.g., an instrument such as scaler), and demonstrating how the procedure/instrument works. In some cases, however, this approach may lead to perseveration6 by the patient/client, and thus should be abandoned.
  • Behaviour problems such as hyperactivity and frustration can complicate the provision of oral healthcare. There is a risk that the invasive nature of some dental hygiene procedures may trigger temper tantrums or self-injurious behaviour such as head banging. To mitigate this risk, a desensitization appointment7 can help the patient/client become familiar with the office, staff, and equipment.
  • Appointments should typically be kept short and positive and be scheduled for early in the day. A calming environment is desirable, and praise and reinforcement of good behaviour should occur after each step of a procedure. Inappropriate behaviour should be ignored as much as possible. 
  • For children with autism, a pre-treatment assessment is often useful to learn about the patient/client from the parents or caregivers; specifically, what works and doesn’t work8. Cooperation should be gained in the least restrictive manner possible. This may include the bringing of comfort items such as stuffed animal or blanket and/or asking the parent/caregiver to sit nearby and hold the patient/client’s hand. Immobilization techniques should only be used when absolutely necessary to ensure patient/client and dental hygienist safety.
  • If other strategies fail, pharmacologic sedation may be required in the management of the patient/client. In extreme circumstances, general anaesthesia may be required for dental/dental hygiene treatment. 
  • Unusual responses to stimuli can interrupt dental hygiene treatment. These include overreaction to sound, bright colours, noise, and touch (while exposure to pain and heat may not provoke much reaction at all). Thus, the patient/client with autism benefits from consistency (e.g., same staff, operatory, and appointment time); minimization of distractions (e.g., reduction of unnecessary sights, sounds, and odours); potential lowering of ambient light (in particular, turning off fluorescent ceiling lights) and possible addition of soft music, depending on advice from patient/client’s caregiver); allowing time for adjustment and desensitization of noise in the dental/dental hygiene setting; and communication between the oral health professional and the caregiver regarding the patient tolerance9. Other specific things that may help include: noise-canceling headphones, weighted blanket or vest, sunglasses, limited talking during the dental procedure, or watching a favorite video. For some autistic patients/clients, a hand mirror to watch may be helpful.
  • Unusual and unpredictable body movements can make it challenging to deliver oral health care, and they may also jeopardize safety. Therefore, the path from the reception area to the dental chair should be clear, and the patient/client’s movements should be observed for patterns. The oral healthcare provider should try to anticipate the movements and modify work approach accordingly. 
  • Panoramic x-rays, which are quick and don’t involve putting items in a patient/client’s mouth, may be better tolerated than conventional intraoral dental x-rays. If necessary, a parent or caregiver can be draped and stay in the room to provide head support during the exposure of the x-ray.
  • To combat caries, caregivers should be advised to offer alternatives to cariogenic drinks and foods as incentives or rewards. 
  • Independence in daily oral hygiene should be encouraged via hands-on demonstrations to patients/clients. As appropriate, a modified toothbrush or floss holder can be employed to make oral self-hygiene easier. 
  • If the patient/client does not like foam from toothpaste, a dentifrice that does not contain sodium laurel sulfate can be used.
  • Daily use of an antimicrobial agent (e.g., chlorhexidine) may be beneficial for some patients/clients. 
  • For the patient/client who cannot brush and floss independently, caregivers should be educated in the provision of daily oral hygiene. This includes consistency in timing, location, and positioning. 
  • A custom mouthguard, if tolerated, can be helpful for a patient/client with bruxism or self-injurious oral behaviour. Other orofacial injury preventive measures include use of seat belts; stair gates; and bike helmets.

Oral manifestations

  • Rates of caries and periodontal disease are comparable to those of the general population. 
  • Bruxism, tongue-thrusting, and self-injurious behaviour (such as biting the lips or picking at the gingiva) are common. 
  • Pica (i.e., chewing and eating objects such as gravel) is sometimes seen, which can damage teeth and other oral cavity structures. 
  • Chipped teeth and bites to the tongue and cheeks can be seen in the autistic patient/client with a co-morbid seizure disorder
  • Gingival hyperplasia can result from phenytoin, an anticonvulsant medication that is commonly prescribed for patients/clients with autism who also experience seizures. Delayed tooth eruption may also occur.
  • Xerostomia can result from medications used to treat comorbid depression, anxiety, or attention deficit hyperactivity disorder.
  • Physical abuse may present as oral trauma, and abuse occurs more frequently in persons with developmental disabilities than in the general population. If child abuse or neglect is suspected, the dental hygienist — a regulated health professional in Ontario — must report such suspicion to the Children’s Aid Society10.

Related signs and symptoms

  • Autism is a complex, pervasive, and lifelong neurodevelopmental disorder that impairs communication, as well as behavioural, intellectual, and social functioning. Autism risk is related to many genetic and environmental factors, and the disorder varies widely in symptoms and severity11. Autism is not caused by vaccination. On the milder (i.e., higher functioning) end of autism spectrum disorder is Asperger syndrome12.
  • At least 1 in 94 Canadians has a diagnosis on the autism spectrum, meaning that more than 150,000 Ontarians currently have ASD. Males are affected four times more frequently than females. As of 2015, an estimated 1 in 54 children and youth between 5 and 17 years of age in Canada had been diagnosed with ASD.
  • Although autism is thought to be present at birth, signs can be difficult to identify during infancy. Signs are usually first noticed by parents and other caregivers after infancy and before a child turns 3 years of age, typically related to failure to meet normal developmental milestones (including language, cognitive, social, and motor skills)13. During the teen years, patterns of behaviour often change, with many teens gaining skills but still lagging behind in their ability to relate to and understand others. Some adults are able to work and live on their own, with such accomplishments related to intelligence and ability to communicate; at least 1/3 are able to achieve at least partial independence. 
  • With the exception of Asperger syndrome, mild to severe intellectual disability occurs in about 70% of persons with ASD. 
  • Persons with the disorder may seem distant, aloof, or detached from other people or their surroundings. Affected children are often non-verbal, lack social awareness, live in “their own world”, and are focused on consistent routine with repetitive peculiar behaviours. 
  • Children and adolescents with autism may display abnormal and inconsistent responses to sensory stimuli, such as: 
    • hypersensitivity to normal noises, sight, smells, taste, touch, and pain; and 
    • hyposensitivity manifesting as high pain threshold, simulated deafness, and reduced or absent startle reaction to loud noises.
  • Behavioural problems are common. These may include tantrums, property destruction, aggression towards others and/or self (i.e., self-injury), abnormal behaviour to communicate, and repetitive body movements (e.g., rocking, spinning, and hand flicking).
  • Common comorbid conditions include intellectual disability, sleep disturbance, and epilepsy. Furthermore, half of Ontario young adults (aged 18 to 24 years) with ASD have at least one other psychiatric diagnosis, such as attention deficit-hyperactivity disorder, anxiety, depression, or conduct disorder. 
  • Gastrointestinal problems (including abdominal pain, constipation, and diarrhea) are common in affected children, sometimes reflecting food intolerance and exacerbated by a severe self-limiting diet.
  • Older children and adults may be fascinated by video games, licence plates, or other phenomena or objects. Preference for being alone and reduced (or lack of) empathy for others are common.

References and sources of more detailed information

Date: March 19, 2018
Revised: March 29, 2023


1 Rett syndrome is a rare, X-chromosome linked disorder that leads to reversal of development, particularly in expressive language and hand use. It is seen almost exclusively in girls (because the genetic defect is usually fatal in males, who have only one X-chromosome). According to recent reclassification (DSM-5), it is no longer automatically considered part of the autism spectrum.
2 This includes a history of premedication being required for oral healthcare or minor surgical procedures.
3 Such behaviour could include head-butting, biting, kicking, punching, hair pulling, spitting, and bolting.
4 See footnote #2 above.
5 See footnote #3 above.
6 Persons with autism often engage in perseveration, which is continuous, meaningless repetition or words or movements. For example, a patient/client may mimic the sound of suction or repeat an instruction over and over again.
7 A desensitization appointment(s) may involve the following: having the patient/client sit alone in the dental chair to become familiar with the treatment setting; doing a cursory examination using one’s fingers; and using a toothbrush (a familiar tool) to brush the teeth and gain additional access to the mouth. Desensitization techniques can also be employed by the family caregiver prior to the dental hygiene appointment, such as providing a mouth mirror and use of light to practise looking in the mouth.
8 Strategies for the dental/dental hygiene care of children with autism include orofacial therapy (a form of desensitization therapy employing stabilization of the jaw and deep pressure and vibration on the joints); errorless learning (continual positive reinforcement); music therapy and counting; social story telling; pivotal response therapy (PRT, which targets pivotal areas of a child’s development such as motivation, self-management, and responsiveness to multiple cues); and the D-Termined program (in which cooperation skills are learned by using repetitive tasks over a short interval).
9 Persons with autism differ in their acceptance of physical contact. Some will refuse any contact in or around the mouth and/or cradling of the head and face. Others will find cradling comforting.
10 Despite the fact that some children with ASD may look neglected or abused, the following are also possibilities: severe self-injurious behaviour (e.g., head banging, scratching, biting, etc.); intermittent or limited pain sensation; lack of sense of danger or what will result in injury; and behaviour/perception that makes changing clothes or bathing very difficult.
11 Management of autism (and its associated co-morbidities) may involve one or more of the following professionals: developmental paediatrician; psychiatrist; clinical psychologist; family physician; gastroenterologist; neurologist; speech therapist; audiologist; occupational therapist; physiotherapist; dietitian; optometrist; social worker; and family counsellor. Early diagnosis and treatment helps children with autism reach their full potential; in Ontario, children and youth (under age 18 years) with ASD (and their families) can receive services through the Ontario Autism Program ( There are currently no medications that cure autism or eliminate all signs/symptoms. However, the anti-psychotic medications risperidone and aripiprazole have been approved by the U.S. Food and Drug Administration (but not Health Canada) to treat irritability in autistic children and adolescents. As well, prescription drugs are used to treat co-morbid conditions and problem behaviours, including epilepsy, depression, anxiety, obsessive-compulsive behaviour, and hyperactivity.
12 A person with Asperger syndrome/disorder experiences delays in the development of social skills and behaviour; however, language development is normal. Often the affected person has an extensive vocabulary and strong verbal skills, although speech is frequently pedantic (i.e., putting excessive emphasis on details) and formal. There tends to be difficulty with nonverbal communication such as body posture and facial expressions. Persons with Asperger’s usually have average or above average intelligence and are capable of self-care, while clumsiness and poor motor skills are common (particularly in the use of hands and fingers). Often the patient/client will have an intense preoccupation about a certain topic or interest. Asperger’s is five times more common in males than females.
13 Key milestones in normal child development include babbling and pointing/waving by 12 months, using single words by 16 months, and using two-word spontaneous phrases by 24 months.

* 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.