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CDHO Advisory: Crohn’s Disease









Use of the dental hygiene interventions of scaling of teeth and root planing including curetting surrounding tissue, orthodontic and restorative practices, and other invasive interventions for persons1 with Crohn’s disease.


Cite as College of Dental Hygienists of Ontario, CDHO Advisory Crohn’s Disease, 2023-11-10


Scaling of teeth and root planing including curetting surrounding tissue, orthodontic and restorative practices, and other invasive interventions (“the Procedures”).



Crohn’s disease


Advanced practice nurses
Dental assistants
Dental hygienists
Health professional students
Public health departments
Regulatory bodies


To guide dental hygienists at the point of care relative to the use of the Procedures for persons who have Crohn’s disease, chiefly as follows.

  1. Understanding the medical condition.
  2. Sourcing medications information.
  3. Taking the medical and medications history.
  4. Identifying and contacting the most appropriate healthcare provider(s) for medical advice.
  5. Understanding and taking appropriate precautions prior to and during the Procedures proposed.
  6. Deciding when and when not to proceed with the Procedures proposed.
  7. Dealing with adverse events arising during the Procedures.
  8. Keeping records.
  9. Advising the patient/client.


Child (2 to 12 years)
Adolescent (13 to 18 years)
Adult (19 to 44 years)
Middle Age (45 to 64 years)
Aged (65 to 79 years)
Aged 80 and over
Parents, guardians, and family caregivers of children, young persons and adults with Crohn’s disease.


For persons who have Crohn’s disease: to maximize health benefits and minimize adverse effects by promoting the performance of the Procedures at the right time with the appropriate precautions, and by discouraging the performance of the Procedures at the wrong time or in the absence of appropriate precautions.



Terminology used in this Advisory

Resources consulted

Terminology varies among centres; the following is used for the purposes of this Advisory.

Crohn’s disease, Crohn disease, is an inflammatory bowel disease that 

  1. may affect any area of the gastrointestinal tract from the mouth to the anus including
    1. ileum, the most commonly affected part of the small intestine
    2. ileocecal region
    3. colon
    4. small intestine.
  2. is also called 
    1. granulomatous ileocolitis
    2. IBD-Crohn’s disease
    3. ileitis
    4. regional enteritis.

Other terminology used in this Advisory is as follows.

  1. Aphthous stomatitis, a recurring condition characterized by the eruption of painful ulcers, commonly called canker sores, on the mucous membranes of the mouth.
  2. Autoimmune system disorder, a condition
    1. in which the immune system 
      1. erroneously attacks and destroys healthy body tissue
      2. creates chronic inflammation
    2. of which there are more than 80 different types. 
  3. Cecum, a pouch that forms the first few centimeters of the large intestine.
  4. Fistula, which 
    1. is an abnormal connection between an organ, vessel, or intestine and another structure
    2. in Crohn’s disease or inflammatory bowel disease such as ulcerative colitis created links between
      1. one loop of intestine and another 
      2. the intestine and the abdominal wall, particularly after surgery
      3. the skin of the buttocks outside the anus and an anal gland just inside the anus, which 
        1. is almost always the result of a previous abscess in the gland
        2. may cause draining of pus, mucus, or stools around the rectal area.
  5. Granuloma, a microscopic collection of cells that 
    1. forms during an infection or inflammatory state
    2. is associated with Crohn’s disease but also occurs in other conditions.
  6. Inflammatory bowel disease (IBD) which 
    1. is not the same condition as irritable bowel syndrome (CDHO Advisory)
    2. includes
      1. Crohn’s disease
      2. ulcerative colitis (CDHO Advisory).
  7. Ileocecal region, which consists of the
    1. ileum, which moves digesting food to the beginning portion of the large intestine
    2. cecum.
  8. Ileum, the last few centimeters of the small intestine.
  9. Incidence, a measure of the rate of occurrence of new cases of a disease or condition.
  10. Tenesmus, a sensation 
    1. of constantly needing to pass stools, even though the bowels are already empty
    2. that may involve straining, pain, and cramping.
  11. Ulcerative colitis (CDHO Advisory), one type of inflammatory bowel disease that affects the lining of the colon and rectum.

Overview of Crohn’s disease

Resources consulted

Crohn’s disease

  1. is
    1. an autoimmune system disorder
    2. described according to the part of the gastrointestinal tract affected.
  2. occurs at any age, but
    1. usually in persons in the age range 15 to 35 years.
  3. varies in incidence throughout the world though 
    1. the incidence has increased markedly in recent years, and particularly in children under the age of 6 years old in Canada
    2. Canada has
      1. among the highest incidences of Crohn’s disease and ulcerative colitis in the world, with prevalence of inflammatory bowel disease estimated at 0.8% of the population (or more than 322,000 persons with IBD)
  4. consists of chronic inflammation which
    1. can arise in any part of the gastrointestinal tract 
    2. sometimes is accompanied by healthy patches of tissue between the diseased areas
    3. arises most frequently in the terminal ileum, especially the section that joins with the colon, which also is often affected.
  5. develops because of inflammation that 
    1. may be an abnormal immune reaction to the normal intestinal bacteria 
    2. thickens gastrointestinal tract wall 
    3. consists of swelling and dilated blood vessels
    4. results in loss of fluid into the tissues.
  6. is characterized by
    1. diarrhea, sometimes bloody, which 
      1. causes impairment of absorption of food resulting in excessive elimination of fat and other foodstuffs 
      2. causes weight loss
    2. abdominal pain of a cramping nature
    3. fecal urgency and poor control of bowel function
    4. fever
    5. in children, delay or failure of growth
    6. various non-specific symptoms that
      1. range from mild to severe
      2. can come and go with periods of flare-ups
      3. chiefly include
        1. abdominal pain, cramp-like
        2. anorexia
        3. diarrhea, watery and persistent 
        4. fatigue
        5. fever
        6. tenesmus
        7. weight loss, unintended
      4. may also include
        1. aphthous stomatitis 
        2. constipation
        3. eye inflammation
        4. fistulas 
        5. gingivitis
        6. joint pain
        7. liver inflammation
        8. rectal bleeding and bloody stools
        9. skin lumps or ulcers
      5. pertain to the part of the gastrointestinal tract affected
        1. in the intestine generally are associated with the narrowing and obstruction of the intestine, which
          1. results from inflammation of the intestine
          2. increases the intestine’s irritability and propensity for spasm, which is associated with pain often cramping in nature 
          3. produces cramps through pressure build-up behind the narrowed intestine 
          4. may  in the narrowing that blockage occurs be severe enough to require immediate medical or surgical attention 
        2. in the colon are associated with 
          1. impairment of the normal function of water re-absorption, resulting in frequent, liquid stools
          2. ulceration of the lining of the colon causing bloody diarrhea
          3. in the later stages of the disease, narrowing and shortening, with decreased absorption of water, fecal urgency, and poor control of bowel function
        3. in the rectum are associated with
          1. tenesmus, which results from inflammation and spasm 
          2. the rectum, which may become a focal point for the inflammation, with the formation of painful anal fissures
          3. large abscesses, which may accumulate, producing severe pain and fever
        4. in the blood system
          1. anemia from blood loss, which may be severe enough to require blood transfusions 
          2. depletion of blood proteins from loss of blood serum into the gastrointestinal tract, and from malnutrition secondary to the debilitating effects of the disease
    7. signs associated with specific abnormalities, such as
      1. fistulas 
      2. abscesses.
  7. in course and prognosis
    1. follows a course that varies considerably in its
      1. clinical picture
      2. complications, which 
        1. may result in
          1. strictures
          2. abdominal abscesses
          3. perianal and intestinal fistulas singly or in combinations
        2. may never develop in some persons
    2. creates an outlook that is mixed because of the
      1. lack of a cure
      2. periods of improvement followed by flare-ups 
      3. increased risk of 
        1. small-intestine cancer
        2. colon cancer.
  8. is of unknown cause likely with various influences on cause and course, including
    1. genetic factors, such as
      1. family history of Crohn’s disease
      2. Jewish ancestry
      3. environmental factors, such as smoking.
  9. is treated symptomatically because it lacks a cure, but can be helped by various  treatments, such as
    1. medications
    2. surgery, to 
      1. remove diseased parts of the 
        1. colon
        2. intestine
        3. rectum
      2. drain abscesses
      3. control hemorrhage
      4. correct effects of failure to grow in children
      5. close fistulas 
      6. relieve narrowing of the intestine
    3. diet and nutrition
      1. though 
        1. no specific diet has been shown to improve or to aggravate Crohn’s disease symptoms 
        2. reactions to specific foods vary from person to person
      2. that 
        1. is balanced with adequate calories, protein, and essential nutrients from various food groups
        2. avoids foods that aggravate diarrhea and gas symptoms especially during flare-ups, which may require
          1. consumption of 
            1. small amounts of food throughout the day
            2. copious amounts of water
          2. avoidance of 
            1. high-fibre foods, including
              1. beans
              2. bran
              3. nuts
              4. popcorn
              5. seeds
            2. fatty, greasy and fried foods 
          3. gas-inducing foodstuffs, such as beans, spicy food, cabbage, broccoli, cauliflower, raw fruit juices and fruits 
          4. limitation of dairy products.
  10. is investigated with
    1. physical examination to reveal
      1. abdominal mass or tenderness
      2. mouth ulcers
      3. skin rash
      4. swollen joints
    2. tests such as 
      1. barium enema
      2. colonoscopy
      3. computed tomography (CT scan), abdomen
      4. endoscopy
      5. enteroscopy
      6. magnetic resonance imaging (MRI), abdomen
      7. sigmoidoscopy
      8. certain laboratory tests, including C-reactive protein
      9. stool culture
      10. upper GI series.
  11. has as yet no methods of prevention available.
  12. relative to social considerations is supported by
    1. Crohn’s disease support groups, Canada
    2. Crohn’s disease support groups, USA

Multimedia and images

Comorbidity, complications and associated conditions

Resources consulted

Comorbid conditions are those which co-exist with Crohn’s disease but which are not believed to be caused by it. Complications and associated conditions are those that may have some link with it. Distinguishing among comorbid conditions, complications and associated conditions may be difficult in clinical practice. 

Comorbid conditions, complications and associated conditions of Crohn’s disease include

  1. abscess
  2. arthritis
  3. bowel obstructions
  4. complications of corticosteroid therapy, such as thinning of the bones
  5. effects on
    1. albumin
    2. C-reactive protein
    3. erythrocyte sedimentation rate
    4. fecal fat
    5. hemoglobin
    6. liver function 
    7. white blood cell count
  6. erythema nodosum
  7. eye lesions 
  8. fistulas in 
    1. anus
    2. bladder
    3. rectum
    4. skin
    5. vagina
  9. gallstones, or other diseases of the liver and biliary system
  10. impaired growth and sexual development in children
  11. joint inflammation 
  12. kidney stones
  13. nutritional deficiencies
  14. oral conditions, such as
    1. aphthous ulceration
    2. gingivitis
  15. pyoderma gangrenosum
  16. skin conditions

Oral health considerations

Resources consulted

  1. Stress
    1. During periods of stress, such as dental work, temporary increases in prednisone therapy may be necessary
    2. Patients/clients may also be stressed by the worry, embarrassment, or depressing effects of or fear of a bowel accident, and may need help with stress management in oral healthcare.
  2. Oral lesions, which occur in as many as 20 percent of persons with Crohn’s disease , include mouth sores, which 
    1. are the most likely to be aphthous stomatitis, which may signal that Crohn’s disease is active
    2. may be one of the earliest indications of Crohn’s disease
    3. may be painful
    4. may be controlled with steroid gels 
    5. may improve when medical treatment is implemented  for the Crohn’s disease.
  3. Non-self-healing granulomas which in Crohn’s disease but not ulcerative colitis occur
    1. chiefly in the intestines
    2. occasionally in children and young adults as orofacial granulomatosis, which may or may not be linked to Crohn’s disease, and which are manifested as  
      1. aphthous oral ulcers
      2. gingival hyperplasia 
      3. mucosal nodularity (cobblestoning)
      4. mucosal tags
      5. swelling of the lips or face.
  4. Dental disorders, of which the risk is increased in Crohn’s disease, include  
    1. cavities
    2. gingivitis
    3. bacterial  infections associated with periodontal disease and tooth abscesses
    4. yeast infections in the mouth. 
  5. Gastrointestinal infection, which
    1. poses a risk because it may cause complications of Crohn’s disease and ulcerative colitis, including
      1. infectious colitis
      2. toxic megacolon
    2. calls for emphasis on
      1. oral hygiene
      2. oral self-care.


Sourcing medications information

  1. Adverse effect database
  2. Specialized organizations
  3. Medications considerations
    All medications have potential side effects whether taken alone or in combination with other prescription medications, or as over-the-counter (OTC) or herbal medications.
  4. Information on herbals and supplements
  5. Complementary and alternative medicine

Types of medications

  1. In Crohn’s disease, because the cause is unknown, treatment is directed at inducing remission, which requires combinations of therapies and medications.
  2. Therapies include
    1. Intestinal rest, an important part of healing, which involves specialized diets and occasional fasting
    2. Attention to nutrition, an important component for digestive health when compromised by Crohn’s disease
    3. Nutrition management 
      1. Supplementation of nutrition, which is recommended especially for children whose growth has been slowed
      2. Intravenous feeding for short periods
      3. While no known foods are proven causes of Crohn’s disease, persons in a flare-up may experience an increase in diarrhea and cramping with foods such as bulky grains, hot spices, alcohol, and milk products.
  3. Stress management combined with appropriate medication for anxiety and stress. 
  4. Anti-Inflammation Drugs
    1. sulfasalazine (Azulfidine®), may be used to treat mildly active Crohn’s colitis
    2. mesalamine (5-ASA), may be used to treat mild to moderate Crohn’s disease
    3. corticosteroids, used in graded doses, high when the disease is at its worst;  dosage is reduced once symptoms are controlled
      budesonide oral (Entocort® EC)
      methylprednisolone oral (Medrol®) 
    4. immune system suppressors, used to block the immune reaction that contributes to inflammation, and immunomodulators, such as
      azathioprine (Imuran®)
      tacrolimus (Prograf®)
      thalidomide (Thalomid®).
  5. Cell-growth inhibitors
    methotrexate (Rheumatrex®).
  6. Corticosteroids, used in graded doses, high when the disease is at its worst; dosage is typically reduced once symptoms are controlled
    budesonide (Entocort EC®)
    hydrocortisone (Cortef®, Hydrocortone®)
    methylprednisolone oral (Medrol®)
  7. Antibiotics, used to treat bacterial overgrowth in the small intestine caused by stricture, fistulas, or prior surgery
    ampicillin (Principen®)
    metronidazole (Flagyl®)
    ciprofloxacin (Cipro®, Proquin®)
    tetracycline (Sumycin®). 
  8. Anti-diarrheal and fluid replacements, used if diarrhea and cramp-like abdominal pain are not relieved when the inflammation subsides following treatment
    1. medications which alter the muscle activity of the intestine to slow the intestinal transit time, taken as needed, such as
      diphenoxylate and atropine (Lomotil®, Lonox®)
      loperamide (Imodium®, Anti-Diarrheal Formula®)
    2. bulk-formers that adjust stool looseness and frequency by binding water and increasing the water content in the gastrointestinal tract, such as
      psyllium (Alramucil®)
    3. bile-salt binders, used when transit time in the small intestine is especially fast
    4. associated dehydration is treated with fluids and electrolytes 
    5. antibiotics for diarrhea
      rifaximin (Xifaxan®). 
  9. Tumor necrosis factor (TNF) inhibitors, which block the action of TNF-alpha, a substance in the body that causes inflammation, such as
    adalimumab injection (Humira®)
    certolizumab injection (Cimzia®)
    etanercept injection (Enbrel®)
    golimumab (Simponi®)
    infliximab (Remicade®)
    tocilizumab injection (Actemra®). 
  10. Monoclonal antibody drugs
    natalizumab Injection (Tysabri®)

    ustekinumab (Stelara®)
    vedoluzimab (Entyvio®)
  11. Janus kinase (JAK)2 inhibitors, such as
    upadacitinib (Rinvoq®), which is a targeted synthetic small molecule
  12. Analgesics 
    acetaminophen, as preferred choice.
  13. Vitamin and iron supplements for anemia which, in severe cases, may require blood transfusion. 
  14. Targeted medications for extra-intestinal conditions such as arthritis or inflammation of the eye. 
  15. Surgery: two-thirds to three-quarters of persons with Crohn’s disease require surgery at some point in their lives, which is reached when medications can no longer control their symptoms.

Side effects of medications

See the links above to the specific medications. 


The dental hygienist in taking the medical  and medications history-taking should 

  1. focus on screening the patient/client prior to treatment decision relative to
    1. key symptoms
    2. medications considerations, especially immunomodulator medications,  prednisone, and other drugs that cause immunosuppression and/or thrombocytopenia (low platelet count)
    3. contraindications
    4. complications
    5. comorbidities
    6. associated conditions
  2. explore the need for advice from the primary or specialized care provider(s)
  3. inquire about
    1. pointers in the history of significance to Crohn’s disease, such as any propensity to infection, whether created by the medications used to treat the Crohn’s disease, the disease itself, or infection, which may require the treating physician’s advice
    2. symptoms indicative of inadequate control of Crohn’s disease, such as the patient/client’s sense of the likelihood of a flare-up
    3. indications of susceptibility to stress
    4. the patient/client’s understanding and acceptance of the need for oral healthcare
    5. medications considerations, including over-the-counter medications, herbals and supplements
    6. problems with previous dental/dental hygiene care
    7. problems with  infections
      1. generally
      2. of the gastrointestinal system
      3. specifically associated with dental/dental hygiene care
    8. the patient/client’s current state of health
    9. how the patient/client’s current symptoms relate to
      1. oral health
      2. health generally
      3. recent changes in the patient/client’s condition.


Identifying and contacting the most appropriate healthcare provider(s) from whom to obtain medical or other advice pertinent to a particular patient/client

The dental hygienist should

  1. record the name of the physician/primary care provider most closely associated with the patient/client’s healthcare, and the telephone number
  2. obtain from the patient/client or parent/guardian written, informed consent to contact the identified physician/primary healthcare provider
  3. use a consent/medical consultation form, and be prepared to securely send the form to the provider
  4. include on the form a standardized statement of the Procedures proposed, with a request for advice on proceeding or not at the particular time, and any precautions to be observed.


Infection Control

Dental hygienists are required to keep their practices current with infection control policies and procedures, especially in relation to

  1. the CDHO’s Infection Prevention and Control Guidelines (2023)
  2. relevant occupational health and safety legislative requirements
  3. relevant public health legislative requirements
  4. best practices or other protocols specific to the medical condition of the patient/client.


The dental hygienist 

  1. should not implement the Procedures without prior consultation with the appropriate primary or specialist care provider(s) if the patient/client
    1. is being treated with medications associated with immunosuppression +/- increased risk of infection (e.g., corticosteroids, azathioprine, 6-mercaptopurine, methotrexate, cyclosporine, biologic response modifier drugs [e.g., anti-tumour necrosis factor drugs and monoclonal antibody drugs], JAK inhibitors, etc.)
    2. is being treated with medications (e.g., azathioprine, 6-mercaptopurine, and sulfasalazine) associated with thrombocytopenia (low platelet count), which can lead to excessive bleeding3
    3. has recently undergone or is about to undergo surgery
    4. has a history of severe gastrointestinal infection
    5. has a condition or treatment which calls for 
      1. antibiotic prophylaxis
      2. pre-medication 
  2. may postpone the Procedures pending medical advice if the patient/client 
    1. appears debilitated or in a flare-up
    2. is experiencing symptoms suggestive of complications of Crohn’s disease or its treatment 
    3. has not complied with pre-medication, including antibiotic prophylaxis, as directed by the prescribing physician 
    4. has recently changed significant medications, under medical advice or otherwise
    5. recently experienced changes in his/her medical condition such as medication or other side effects of treatment
    6. is unable to provide the dental hygienist with sufficient information about
      1. medications
      2. the medical history
    7. has symptoms or signs of 
      1. exacerbation of the medical condition
      2. comorbidity, complication, or an associated condition of Crohn’s disease
    8. has not recently or ever sought and received medical advice relative to oral healthcare procedures
    9. is deeply concerned about any aspect of his or her medical condition.  


Dental hygienists are required to initiate emergency protocols as required by the College of Dental Hygienists of Ontario’s Standards of Practice, and as appropriate for the condition of the patient/client.

First-aid provisions and responses as required for current certification in first aid.


Subject to Ontario Regulation 9/08 Part III.1, Records, in particular S 12.1 (1) and (2) for a patient/client with a history of Crohn’s disease, the dental hygienist should specifically record

  1. a summary of the medical and medications history
  2. any advice received from the physician/primary care provider relative to the patient/client’s condition
  3. the decision made by the dental hygienist, with reasons
  4. compliance with the precautions required
  5. all Procedure(s) used
  6. any advice given to the patient/client.


The dental hygienist should 

  1. urge the patient/client to alert any healthcare professional who proposes any intervention or test that he or she
    1. has a history of Crohn’s disease
    2. is taking medication for Crohn’s disease or any comorbidity, complication or associated condition
  2. should discuss, as appropriate 
    1. with parents/guardians of children the caution that
      1. during periods of stress, such as dental work, temporary increases in prednisone therapy may be necessary, and
      2. they should notify the child’s physician of the occurrence of such bodily stresses
    2. with the family caregiver the importance of oral care for persons at an advanced stage of the disease, with emphasis on maintaining an infection-free environment, and advice on wearing gloves 
    3. medication side effects such as dry mouth, and recommend treatment
    4. the importance of the patient/client’s
      1. self-checking the mouth regularly for new signs or symptoms
      2. reporting to the appropriate healthcare provider any changes in the mouth
    5. the need for regular oral health examinations and preventive oral healthcare 
    6. oral self-care including information about 
      1. choice of toothpaste
      2. tooth-brushing techniques and related devices
      3. dental flossing
      4. mouth rinses
      5. management of a dry mouth 
    7. the importance of an appropriate diet in the maintenance of oral health
    8. for persons at an advanced stage of a disease or debilitation
      1. regimens for oral hygiene as a component of supportive care and palliative care
      2. scheduling and duration of appointments to minimize stress and fatigue 
    9. comfort level while reclining, and stress and anxiety related to the Procedures
    10. medication side effects such as dry mouth, and recommend treatment
    11. mouth ulcers and other conditions of the mouth relating to Crohn’s disease , comorbidities, complications or associated conditions, medications or diet
    12. pain management.



  1. Promoting health through oral hygiene for persons who have Crohn’s disease.
  2. Reducing the adverse effects (including stress that is excessive for the patient/client) by
    1. informed discussion with the person’s prescribing physician, as necessary
    2. obtaining medical advice about the Procedures during a flare-up
    3. obtaining an accurate history, including medications
    4. generally increasing the comfort level of persons in the course of dental-hygiene interventions 
    5. using appropriate techniques of communication
    6. providing advice on scheduling and duration of appointments.
  3. Reducing the risk that oral health needs are unmet.


  1. Failing to 
    1. recognize the significance of mouth sores in Crohn’s disease
    2. advise the patient/client to seek medical advice if he or she has not already done so.
  2. Performing the Procedures at an inappropriate time, such as 
    1. during a period of severe debilitation or during a flare-up without obtaining medical advice or when necessary adjustments to medications have not been made
    2. when the patient/client is using prednisone or other medications associated with immunosuppression, and informed advice has not been obtained from the prescribing primary care or specialist provider
    3. when the patient/client is using medications associated with thrombocytopenia, and informed advice has not been obtained from the prescribing primary care or specialist provider
    4. in the presence of acute oral infection without prior medical advice 
    5. when the patient/client has history of severe gastrointestinal infection and medical advice has not been obtained
    6. in the presence of complications for which prior medical advice is required
    7. in the presence of acute oral infection without prior medical advice.
  3. Disturbing the normal dietary and medications routine of a person with Crohn’s disease.
  4. Inappropriate management of pain or medication.






2011-04-01; 2019-12-12; 2023-11-10


College of Dental Hygienists of Ontario, regulatory body
Greyhead Associates, medical information service specialists


College of Dental Hygienists of Ontario


College of Dental Hygienists of Ontario, Practice Advisors


Dr Gordon Atherley
O StJ , MB ChB, DIH, MD, MFCM (Royal College of Physicians, UK), FFOM (Royal College of Physicians, UK), FACOM (American College of Occupational Medicine), LLD (hc), FRSA

Dr Kevin Glasgow

Lisa Taylor

Kyle Fraser
RDH, BComm, BEd, MEd

Carolle Lepage


The College of Dental Hygienists of Ontario gratefully acknowledges the Template of Guideline Attributes, on which this advisory is modelled, of The National Guideline Clearinghouse™ (NGC), sponsored by the Agency for Healthcare Research and Quality (AHRQ), U.S. Department of Health and Human Services.

Denise Lalande
Final layout and proofreading

© 2009, 2011, 2019, 2023 College of Dental Hygienists of Ontario


1 Persons includes young persons and children.
2 JAK = Janus kinase
3 Flare-ups of the underlying disease itself can rarely be accompanied by thrombocytopenia.