Mental Disorders

Developmental Disorders

Mental Retardation

Mental retardation (MR) is defined as significant subaverage general intellectual functioning existing in conjunction with deficits in adaptive behavior and is manifested during the developmental period prior to age 18. It is not an illness but an impairment in intellectual and adaptive functioning. The cause is not always known; rarely can a single cause be identified. In 75 percent of cases the cause is unknown.

Some of the known causes are:

  • chromosomal abnormalities
  • prenatal conditions (rubella, alcohol use, drug use)
  • perinatal (anoxia)
  • postnatal (meningitis, encephalitis, trauma, cultural deprivation, severe malnutrition)

Mental retardation is defined by Intelligence Quotient (IQ) scores or by categories such as:”educable,” “trainable,” “total care”:

  • normal intellectual functioning, IQ = 100
  • mild mental retardation, IQ = 55-70 (educable)
  • moderate mental retardation, IQ = 40-55 (trainable)
  • severe mental retardation, IQ = 25-40 (some training possible)
  • profound mental retardation, IQ <25 (total care is required)

(Note: Due to variability in testing, these classificatrions are not always appropriate and an individualized approach is always indicated.)

3 to 5 individuals in 100 are classified as mentally retarded. 85 percent are mildly mentally retarded (IQ > 55) and can function in the community environment. Mental retardation may be the most common disabling condition the dentist will encounter in private practice.

Mental retardation can be associated with other disorders, e.g.:

  • seizure disorders
  • cardiac anomalies
  • emotional disorders

Consultation with the physician, family and care givers is essential for:

  • obtaining an accurate medical history
  • providing appropriate oral health care
  • obtaining informed consent
  • managing behavior
  • insuring that daily oral hygiene is performed

Oral findings may include:

  • poor oral hygiene
  • malocclusion
  • enamel deficits
  • gingival hyperplasia
  • tongue thrusting habits
  • clenching and bruxism
  • drooling
  • self-injurious behavior
  • pica (ingestion of inedible objects)

Communicating with the patient who has mild mental retardation:

  • minimize distractions
  • use short explanations
  • use simple language
  • take more time to present information
  • avoid explanation of causes
  • focus on effects of lack of oral hygiene
  • teach activities rather than concepts
  • encourage consistency
  • use “tell-show-do”
  • use positive reinforcement
  • use verbal praise

Communicating with the patient who has severe mental retardation:

  • use shorter simpler explanations,
  • greater repetition of instructions and
  • use more practice of oral hygiene procedures
  • more extensive use of positive reinforcement

Accommodating the behavior of these individuals may present a challenge. Behavioral difficulties are often related to cognitive functioning. Behavior management may require:

  • “tender loving care”
  • “gentle firmness” (verbal control)
  • desensitization
  • restraints
  • sedation
  • general anesthesia
  • a combination of the above strategies

Down Syndrome

Trisomy 21 (Down Syndrome) is probably the most common developmental disability. It is associated with an extra chromosome of the twenty first group. These individuals have 47 chromosomes rather than the normal complement of 46.The overall incidence of Down Syndrome is one in 700 live births, however, the incidence increases with the age of the mother; e.g., at age 54 the incidence is 1 in 54.

The typical facial appearance includes:

  • midface hypoplasia
  • slanted eyes
  • broad flat nose
  • flat occiput
  • short stature

Medical consultation is important, associated conditions include:

  • mental retardation
  • congenital cardiac anomalies (antibiotic propohylaxis is often required)
  • seizure disorders
  • immunological impairment
  • upper respiratory disease
  • leukemia
  • hepatitis

Oral conditions include:

  • low caries rate
  • increased risk of severe periodontal disease
  • short conical roots
  • tongue thrusting
  • protruding tongue
  • macroglossia
  • fissured tongue
  • malocclusion (Class III)
  • narrow palate
  • delayed eruption
  • bruxism
  • drooling
  • self injurious behavior (SIB)

Clinical management includes:

  • possible seizure management
  • restricted nasal passages may prevent the use of nitrous oxide
  • possible increased gag reflex
  • sedation may help to control patient anxiety
  • difficult cases may require treatment under general anesthesia

The treatment plan must consider problems with drug-induced gingival overgrowth. Optimal oral hygiene is required to prevent gingival overgrowth. Removable prostheses may be contraindicated if the seizure disorder is not well contolled. If anterior teeth are repeatedly traumatized and repaired; consider acrylic veneers instead of porcelain in fixed prostheses.

Extra attention should be focused on oral hygiene. Educate caregivers. Prescribe a chlorhexidine rinse. Perioguardª tastes better than Peridexª.


Autism is a developmental disorder characterized by:

  • poor social skills (inability to get along with people)
  • lack of interpersonal relationships
  • abnormal speech and language
  • repetitive stereotyped activities
  • mental retardation is common

These individuals are often receiving psychotopic medications which can cause xerostomia

In addition they have a known desire for sweet foods and generally have poor oral hygiene.

Therefore, these patient’s are at increased risk for increased dental caries and periodontal disease

Patient’s behavioral problems may present management difficulties. Behavior management should include behavior modification, positive einforcement and desensitization; however, sedation, restraint, and general anesthesia may be necessary when oral disease is extensive.

Patients who have autism may be receiving one or more of the following medications:

  • antipsychotics

Psychiatric Disorders

Major Depression

Major depression is an affective disorder which is an out ward manifestation of one’s feelings or mood. It characterized by prolonged depression of mood which affects the patient’s life.There is a prominent and persistent loss of interest in and pleasure in daily activities and pastimes.

Major depression is associated with:

  • a loss of appetite
  • weight loss
  • sleep disturbances
  • decreased energy
  • difficulty with memory
  • concentration (easily distracted, indecisive).
  • sad appearance
  • feelings of worthlessness, hopelessness, and guilt
  • thoughts of death or suicide
  • poor personal hygiene

Associated oral problems include:

  • poor oral hygiene
  • rampant caries
  • generalized advanced periodontitis
  • oro-facial pain
  • xerostomia
  • poor nutrition, poor diet

Treatment consisits of:

  • medications
  • psychotherapy
  • diet counseling
  • exercise
  • correction of sleep disturbances
  • electroconvulsive therapy (ECT) occasionally

Psychotropic medications include:

Tricyclic antidepressants:

  • Sinequan (doxepin)
  • Elavil (amitryptiline)
  • Anafranil (clomipramine)
  • Tofranil (imipramine)
  • Etrafon ( perphenazine and amitryptiline)
  • Pamelor (nortryptiline)

MAO inhibitors:

  • Nardil (phenlzine sulfate)
  • parnate ( tranylcypromine sulfate)

Miscellaneous anti-depressants:

  • Prozac (fluoxetine)
  • Desyrel (trazadone)
  • Paxil

Precautions must be taken with patients receiving tricyclic antidepressants. They may affect the cardiovascular system causing:

  • hypotension
  • orthostatic hypostension
  • tachycardia
  • arrythmias
  • myocardial infarction
  • congestive heart failure
  • xerostomia

Adverse drug interactions may occur between tricyclic antidepressants and; sedatives, hypnotics, general anesthetics, barbiturates, and narcotics which could result in severe respiratory depression. There is continuing debate regarding the use of local anesthetics containing epinephrine; the pressor effect can be potentiated by tricyclics; always aspirate before injecting

Precautions must be taken with patients receiving MAO inhibitors; disturbances in cardiac rate/rhythm may be seen. Do not use a local anesthetic containing epinephrine or neo-cobefrin this can preceipitate a hypertensive crisis resulting in CVA, MI or death. Hypotension and xerostomia may be caused by this drug as well.

Patients undergoing ECT may receive drugs that diminish protective reflexes that guard against aspiration and should be evaluated for loose teeth, gross calculus and loose prostheses; a mouthguard may be indicated.

Bipolar Disorder

Bipolar disorder is also known as Manic-Depressive Disorder. Patient suffer from alternating, prolonged episodes of extreme elation and depression.

Periods of mania are characterized by hyperactivity involving excessive participation in multiple activities (sexual, occupational, political, religious, etc.) which is unrecognized by the patient. Speech is often pressured, loud, rapid, theatrical, dramatic, difficult to interpret, with abrupt changes in topic. The most common complications of manic episodes are substance abuse and the consequences of actions resulting from impaired judgement

Persons with bipolar disorder:

  • are easily distracted
  • display grandiose delusions in which they claim a special relationship to well known person
  • may go days with little or no sleep and not appear tired
  • may have very labile mood with rapid shifts to anger or depression

Periods of depression are characterized by a loss of interest in almost all daily activities

Oral problems manifested during mania are abrasion of mucosa and teeth from vigorous brushing. During depression; poor oral hygiene, rampant caries, periodontal disease, and oro-facial pain.

Lithium carbonate is effective in treating the manic phase while depressive episodes are treated by temporary administration of antidepressants. Long term lithium therapy may result in complaints of generalized stomatitis and xerostomia; artificial saliva may make the patient more comfortable and better able to tolerate the medication. NSAIDs may affect renal flow and increase blood levels of lithium; consult with patint’s physician.


Schizophrenia is a psychotic disorder characterized by varying degrees of personality disorganization. The individual’s thought processes are disupted by bizarre delusions and perceptual disturbances such as hallucinations. This decreases the individual’s ability to communicate and work with others. Therefore, routine daily functions such as work, social relationships, and self care are impaired.

These patient’s often have severe dental problems. Administration of mood altering drugs can cause xerostomia with associated caries mucositis and discomfort. Since they are frequently confused, depressed, withdrawn or anxious they often neglect or resist dental care

Individuals with schizophrenia often manifest the following oral problems:

  • decreased salivary flow
  • increased caries
  • increased periodontal disease
  • occasional parotitis
  • attrition associated with tardive dyskenisia

Patients should be approached slowly in a nonthreatening manner and should be warned of what to expect during the procedure.

Medico-legal competence may have to be established via consultation with patient’s psychiatrist

Individuals with bipolar disorder may be receiving psychotropic agents such as:

  • phenothiazines (Mellaril, Prolixin, Thorazine)
  • Haldol
  • Navane
  • Thiothixene
  • Clozapine
  • Risperidone
  • Lithium
  • Alprazolam

Aspirate when injecting local anesthetic, use no more than 3 carpules containing 1:100,000 epinephrine.

Post-Traumatic-Stress Disorder

Post-traumatic-stress disorder is characterized by the “reexperiencing” of a psychologically traumatic event. It is most commonly associated with veterans of the War in Viet Nam, however, it is also seen in individuals who experience trauma such as natural disasters, airplane crashes, and rape. The traumatic event is reexperienced as recurring disruptive intrusive thoughts of past experiences and nightmares. These experiences increase during periods of stress such as illness, marital discord, financial problems, and dental treatment.

Symptoms associated with PTSD include:

  • irritability
  • aggressive behavior
  • explosive behavior
  • impulsive behavior (unexplained absence, sudden trips)
  • alcohol or drug use
  • feelings of detachment
  • estrangement
  • lack of emotions (“psychic numbing”)
  • marital and family problems
  • problems at work

Associated medical problems (possibly due to prolonged periods of stress) include:

  • cardiovascular disease
  • bypass surgery
  • GI disease (ulcerative colitis)

Frequently manifested oral problems include:

  • poor oral hygiene
  • rampant decay
  • advanced generalized periodotitis
  • glossodynia
  • TMJ disturbances

Individuals with PTSD may be receiving antidepressant medication. (See section on major depression for precautions)

Attempt to establish a trusting professional and open relationship. Esthetic restoration of the patient’s teeth can enhance self esteem, social rehabilitation and vocational rehabilitation.


Dementia can be classified as a neurologic or psychiatric disorder. Alzheimer’s disease is a type of dementia. It is defined as a loss of intellectual function severe enough to interfere with social and vocational activities. Dementia is characterized by losses in memory, judgement, abstract thought and other higher cortical functions.The characteristic poor short-term memory can cause increased agitation, disorientation, and inappropriate behavior in unfamiliar settings

As the disease reaches a more advanced state it may be characterized by:

  • incontinence
  • loss of self care abilities
  • limb contractures
  • vegetative states
  • death

Individuals over 65 years of age are most susceptible. There is a 2 to 3 percent occurrence between ages 65 and 79, and a 20 percent occurence after age 80.

Dementia undermines oral health due to a decreased willingness to perform oral hygiene, and a decreased ability to properly report symptoms of pain and dysfunction. In addition, patients often receive cholinesterase inhibitors (tacrine, donepizil) which may cause xerostomia leading to disasterous dental consequences.

Frequently manifested oral problems include:

  • maxillofacial injuries
  • traumatic oral ulcerations
  • poor oral hygiene
  • extensive caries
  • periodontal disease
  • missing and broken teeth
  • attrition
  • salivary gland dysfunction
  • severe atrophy of residual ridges secondary to ill-fitiing dentures

Comprehensive oral rehabilitation should be completed as early as possible for the patient with a progressive dementia since the patient will eventually lose the ability to cooperate during dental treatment. Frequent preventive oral health visits are indicated

Use caution when prescribing medications, age-related changes in the liver and kidneys affect dental therapeutics (anesthetics, analgesics). As a rule of thumb, in the elderly a single dose of many drugs produce a peak blood level twice as high and a half-life twice as long and in the younger patient. Consult with the patient’s physician.

Attrempt to create a warm reassuring safe environment; explain procedures, smile, make eye contact, gently touch the patient. Use short words, short sentences and repetition.

Legal competency may have to be determined in consultation with the patient’s physician.

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