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CDHO Advisory: Chemotherapy









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 receiving or who have received chemotherapy.


Cite as College of Dental Hygienists of Ontario, CDHO Advisory Chemotherapy, 2024-03-20


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





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 receiving or who have received chemotherapy, 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 receiving or who have received chemotherapy.


For persons receiving or who have received chemotherapy: 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

Chemotherapy, “chemo”, cancer chemotherapy, cancer medication therapy, cytotoxic chemotherapy

  1. is a method of treating cancer by using medications with the intention of
    1. curing cancer, to the extent that the chemotherapy has destroyed the cancer cells so that they can no longer be detected, and that there is good reason to believe that they will not recur
    2. controlling cancer, to the extent that the chemotherapy keeps the cancer from spreading, slows its growth, or destroys cancer cells that have spread to other parts of the body
    3. providing palliative care, to the extent that the chemotherapy shrinks tumours that are causing pain or pressure. 
  2. comprises various types, including
    1. combination chemotherapy, destroying cancer cells with a mix of chemotherapy medications
    2. neoadjuvant chemotherapy, shrinking a tumour before surgery or radiation therapy 
    3. adjuvant chemotherapy, destroying cancer cells missed by the surgery or radiation 
    4. ablative chemotherapy, destroying existing bone marrow prior to its replacement by stem cells or bone marrow from a donor 
    5. palliative chemotherapy, reducing pain and other symptoms of cancer.
  3. is also used to kill bacteria, viruses, fungi, and not only cancer cells. 

Other terminology used in this Advisory is as follows.

  1. Cerebrospinal fluid
    1. circulates throughout the central nervous system within the spine and skull
    2. delivers nutrients to and removes waste from the brain and spinal cord
    3. cushions the brain and spinal cord against trauma.
  2. Cytotoxicity, toxicity to or destructiveness of a cell.
  3. Immunosuppression, when the response of the body’s immune system is reduced or absent as a result of disease or treatment.
  4. Myelosuppression, where bone marrow activity is decreased, thereby reducing the production of red blood cells, white blood cells, and platelets, which occurs as a side effect of some cancer treatments. 

Overview of chemotherapy

Resources consulted


of chemotherapy has the intention of

  1. curing a cancer
  2. stopping a cancer from spreading
  3. relieving symptoms of a cancer that is incurable.


involves various types of chemotherapy 

  1. varies considerably 
    1. among patients/clients in the way it affects the cancer and in its side effects
    2. among cancer types
    3. in duration, pattern and frequency of delivery
  2. is delivered in specialized clinics in hospitals, though some chemotherapy treatments can be delivered at home, which requires special support for family caregivers
  3. includes medications that travel the bloodstream throughout the entire body, so that chemotherapy is considered systemic treatment
  4. is administered 
    1. variously by 
      1. mouth as tablets or capsules
      2. injection
        1. intra-muscular
        2. intravenous
        3. into the cerebrospinal fluid
        4. by catheter inserted into a large vein close to the heart when treatment is required over lengthy periods
      3. along with radiation therapy (CDHO Advisory) before, during or after the chemotherapy
      4. may be accompanied by surgery or biological therapy
      5. most commonly in cycles which provide for periods of rest, sometimes lengthy
  5. is routinely checked against clinical progress and adjusted accordingly
  6. damages not only cancer cells, but also healthy ones though, over time, the healthy cells recover and repair themselves
  7. renders persons vulnerable to infection, which accounts for a major proportion of deaths
  8. may call for long-term or even life-long oral healthcare.


of chemotherapy 

  1. is most effective on cells that divide often to make new cells, a characteristic of most cancer cells
  2. also damages normal, healthy cells, especially cells that divide quickly, including those in the
    1. oral mucosa, which may lead to oral side effects such as mouth sores
    2. blood
    3. hair
    4. lining of the gastrointestinal tract.

Side effects

  1. of chemotherapy generally 
    1. vary considerably from person to person even for a particular chemotherapy medication, dependent on the
      1. treatment schedule
      2. particular medication
      3. body’s reaction to the treatment overal
    2. arise from damage to normal, healthy cells, resulting in
      1. bleeding problems
      2. fatigue
      3. increased risk of infection, requiring
        1. personal hygiene including hand washing
        2. caution with pets and other animals
      4. loss of weight, requiring attention to calorific intake
      5. oral side effects
      6. pain associated with neurological damage
      7. poor appetite
    3. vary in time of occurrence
      1. arising
        1. during treatment
        2. immediately after treatment
        3. throughout an extended period following treatment
      2. depending on the length of time healthy cells need to recover from chemotherapy; the most affected of which are those that grow quickly
    4. often gradually disappear when treatment is completed
      1. depending on the 
        1. types of medications used
        2. person’s general physical health
      2. though not always disappearing completely or permanently
    5. may include
      1. causing a cancer after a period of years
      2. life-threatening allergic reactions to a chemotherapy medication, which are medical emergencies room and which are signalled by some combination of
        1. sudden or severe itching  
        2. rash or hives 
        3. wheezing or difficulty breathing
      3. mood-altering feelings, which occur commonly with chemotherapy chiefly  because it is inherently stressful, including
        1. anger
        2. anxiety
        3. depression 
        4. fatigue
        5. fear
        6. frustration
        7. helplessness
        8. loneliness
      4. debilitation-related symptoms, such as
        1. pain, which arises from the chemotherapy treatment overall, rather than particular chemotherapy medications
        2. fatigue
        3. nausea 
        4. vomiting
        5. hair loss.
      5. chemo brain (also known as chemo fog, cancer-related brain fog, and cancer-related cognitive impairment or cognitive dysfunction), which describes thinking and memory problems that can occur before, during, and after chemotherapy (or certain other cancer treatments, including radiotherapy and hormone treatment)
  2. Includes oral side effects of chemotherapy, which
    1. are related to the general side effects of chemotherapy and are chiefly
      1. immunosuppression, which impairs the body’s defences against microorganisms, creating high risk of
        1. periodontal and odontogenic abscesses
        2. viral and fungal infection
      2. myelosuppression, which reduces
        1. platelet counts, which impairs blood clotting and creates risk of excessive hemorrhage
        2. other white cells circulating in the blood, which impairs the body’s defences against infection
      3. cytotoxicity, which produces mucositis, the most common acute oral side effect of chemotherapy, which usually occurs 5 to 7 days after the start of chemotherapy
      4. mucositis and immunosuppression together, which
        1. arises from chemotherapy treatments involving combinations of medications
        2. creates extreme vulnerability to opportunistic infections
      5. bleeding tendency, which is signalled by bleeding from the gums or nose 
      6. infection risk, associated with depression of the white cell count
    2. create changes in the mouth, lips and throat during chemotherapy, including
      1. hyposalivation, associated with changes in saliva, such as
        1. increased viscosity
        2. reduced volume
      2. mucositis, associated with
        1. mucosal ulceration
        2. oropharyngeal pain
      3. mucosal infection
        1. fungal
        2. viral
      4. gingivitis
      5. infections of teeth or tongue
      6. exacerbation of dental or periodontal disease
      7. caries or demineralization
      8. changes in taste and smell
      9. increased sensitivity to hot or cold foods
      10. eating difficulty attributable to problems in the mouth
    3. bring additional changes following cancer therapy, including chemotherapy-induced
      1. mucosal conditions
        1. fibrosis
        2. atrophy
        3. sensitivity
      2. persistent salivary gland dysfunction
      3. problems with dental prosthesis fit or function
      4. osteoradionecrosis (CDHO Advisory)
      5. oropharyngeal or head and neck pain fibrosis of muscles or soft tissue
      6. neuropathy
      7. speech difficulties
      8. esthetic concerns
    4. have particular consequences for children, including observations that
      1. childhood cancer survivors may be at an increased risk of caries and various developmental malformations of teeth, whether from the anti-cancer therapy or from the cancer itself
      2. children treated in the early years of their lives display the most severe dental defects, suggesting that immature teeth are at a greater risk of developmental disturbances than fully developed teeth.
    5. include side effects that lower the quality of life, such as
      1. pain
      2. fatigue 
      3. nausea 
      4. vomiting
      5. hair loss.


varies from complete recovery to palliative treatment, depending on

  1. the stage of the underlying cancer
  2. whether the cancer is localized or systemic
  3. the cytotoxic agents chosen
  4. the person’s general health and medical conditions other than the cancer.

Social considerations 


  1. many patients/clients’ feeling well enough to receive oral healthcare, which requires particular consideration to the oral health implications of chemotherapy’s side effects relative to the Procedures and to the advice given to patients/clients
  2. the delivery of certain chemotherapy regimens to persons living at home, which requires support of family caregivers and advice on the maintenance of oral hygiene
  3. the ability of many people to work during chemotherapy, who need to match their workloads to how they feel, which may require adaptation of work organization and arrangements.

Comorbidity, complications and associated conditions

Comorbid conditions are those which co-exist with chemotherapy 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 is especially difficult for chemotherapy. 

  1. It appears to be that, among cancer patients with comorbidities, use of chemotherapy is diminished and cancer outcomes are generally inferior when compared to use and outcome among cancer patients without comorbidities.

Oral health considerations

Resources consulted

  1. The Procedures are contraindicated without prior advice from the treating physician or chemotherapy or radiation therapy team about 
    1. implementing the procedures for patients/clients for whom cancer chemotherapy 
      1. is planned, when oral healthcare treatment is best delivered before the chemotherapy is begun, with the intention of reducing dental emergencies during the delivery of chemotherapy, and should include
        1. thorough periodontal cleaning
        2. appropriate mouth care generally
      2. is underway, when oral healthcare treatment should be undertaken only on an emergency basis, which
        1. may include periodontal debridement if warranted by
          1. active periodontal disease
          2. medical need for removal of a source, actual or potential, of infection
        2. requires account to be taken of the 
          1. white blood cell count
          2. platelet count
          3. need for antibiotic prophylaxis
          4. the optimum point for oral healthcare in the individual patient/client’s treatment cycle
    2. risk of infection, which  
      1. is associated with depression of the white cell count and may require antibiotic prophylaxis for a patient/client with low white blood count
      2. is countered by
        1. consulting with the treating physician
        2. obtaining medical advice prior to the use of aspirin, acetaminophen and any other anti-pyretic medications
        3. categorizing a fever in excess of 38⁰ C as an indication for immediate medical advice 
        4. emphasizing the need for close attention to care of the mouth, and oral and general hygiene on the part of the patient/client 
        5. giving close attention to infection control on the part of the dental hygienist
        6. care of the mouth before chemotherapy and during and after chemotherapy
    3. risk from bleeding, which 
      1. requires consultation with the treating physician
      2. may lead the treating physician to recommend a platelet count prior to the Procedures.
  2. The mouth of the patient/client receiving chemotherapy 
    1. provides conditions favourable for microbial growth, particularly if the patient/client is debilitated
    2. is a portal of entry for infection of lungs, digestive tract, and circulatory system 
    3. is especially susceptible to oral infection because
      1. pathogenicity of oral flora may be enhanced
      2. host-defence mechanisms may be impaired
    4. requires meticulous attention to oral infection control, which
      1. includes particular attention on the part of
        1. the oral healthcare provider
        2. the patient/client receiving chemotherapy
      2. involves well-laid oral healthcare treatment plans, including appropriate recall appointments 
      3. may prevent or reduce oral complications such as
        1. mucositis 
        2. local and systemic infection
      4. may help enhance the general health and comfort of the patient/client.
  3. Side effects include
    1. allergic reactions to chemotherapy medications, which may be severe enough to be a medical emergency
    2. oral side effects of chemotherapy, which 
      1. are usually acute
      2. often subside shortly after the chemotherapeutic medications lose their biological effectiveness
      3. include mouth, throat and lip changes, which can affect teeth, gums, lining of the mouth, and salivary glands
    3. non-oral side effects of chemotherapy, of which some raise special concerns for oral healthcare, including
      1. anemia, arising from chemotherapy effects on bone marrow 
      2. appetite changes, which sometimes arise from mouth problems that make eating painful; eating well is important for patients/clients receiving chemotherapy, which can of itself also be associated with weight loss or gain
      3. bleeding, caused by chemotherapy-induced abnormally low counts of platelets, which may cause bruising, small hemorrhages into the skin, or bleeding from the nose or mouth
      4. diarrhea, caused by infections, chemotherapy, or medications used to treat constipation
      5. fatigue, which may persist after treatment is concluded, is associated with chemotherapy and its accompanying medications, the pressure of frequent visits for healthcare, feelings such as stress, anxiety, and depression, and with various medical problems.


Sourcing medications information

  1. Adverse effect databases
  2. Specialized organizations
  3. Information about specific medications
  4. 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.
  5. Information on herbals and supplements 
  6. Complementary and alternative medicine

Types of medications

Chemotherapy medications

  1. are delivered by various routes, including
    1. injection: intramuscular, subcutaneous or directly into a cancerous lesion of the skin
    2. intra-arterial: directly into the artery supplying the cancer
    3. intraperitoneal: directly into the peritoneal cavity
    4. intravenous: directly into a vein, which
      1. may involve a vein-residing catheter instead of an IV needle
      2. may be accompanied by anti-nausea medication
      3. requires from 15 minutes to 3 hours for each treatment
    5. topical: as cream for the skin.
    6. oral: pills, capsules, or liquids, which 
      1. require strict adherence to the prescribed directions
      2. may require medication reminders, such as dosettes
      3. could require an advisory procedure for dealing with forgotten doses
      4. requires hand-washing after taking the chemotherapy substance
      5. requires avoidance of contact with the medication by persons other than the patient/client
      6. requires cleansing of the spoon and other utensils used for the chemotherapy substance.
  2. used for and with chemotherapy are indexed in resources such as

Side effects of medications

See the resources 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
    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 chemotherapy,  such as changes in the mouth
    2. symptoms indicative of side effects of chemotherapy, such as
      1. infection history
      2. bleeding problems
      3. severe allergic reactions
    3. changes in chemotherapy and other medications prior to and during chemotherapy treatments made by the patient/client without the advice of the chemotherapy provider or treating physician; these 
      1. may involve
        1. prescription medications
        2. over-the-counter medications
        3. vitamin supplements
        4. mineral supplements
        5. herbal remedies and other natural health products
        6. complementary and alternative therapies.
      2. should be accurately reported by the dental hygienist to the chemotherapy provider or treating physician
    4. the patient/client’s understanding and acceptance of the need for oral healthcare
    5. problems with previous dental/dental hygiene care
    6. problems with infections generally and specifically associated with dental/dental hygiene care
    7. the patient/client’s current state of health
    8. 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 (2024)
  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.


With active chemotherapy or radiation therapy the Procedures are contraindicated without prior consultation with the appropriate chemotherapy or radiation treatment provider(s).

The dental hygienist 

  1. should not implement the Procedures without prior consultation with the appropriate primary or specialist care provider(s)
    1. if the patient/client’s current treatment includes chemotherapy with or without radiation therapy
    2. if the patient/client has undergone or is about to undergo chemotherapy with or without radiation therapy
    3. if the patient/client’s condition or treatment calls for 
      1. antibiotic prophylaxis
      2. pre-medication
  2. may postpone the Procedures pending medical advice if the patient/client 
    1. appears debilitated
    2. is experiencing symptoms suggestive of complications of chemotherapy 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. bleeding problems
      3. infections that may be related to chemotherapy or radiation therapy
      4. a history such as life-threatening allergic reactions associated with chemotherapy
    7. has symptoms or signs of 
      1. exacerbation of the medical condition
      2. comorbidity, complication or an associated condition of chemotherapy
      3. not recently or ever sought and received medical advice relative to oral healthcare procedures
      4. 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 chemotherapy, 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 
    1. that he or she has a history of chemotherapy 
    2. to the medications he or she is taking
  2. should discuss, as appropriate 
    1. 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
    2. the need for regular oral health examinations and preventive oral healthcare 
    3. 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 
    4. the importance of an appropriate diet in the maintenance of oral health
    5. for persons at an advanced stage of a cancer or debilitation
      1. regimens for oral hygiene as a component of supportive care and palliative care
      2. the role of the family caregiver, with emphasis on maintaining an infection-free environment through hand-washing and, if appropriate, wearing gloves
      3. scheduling and duration of appointments to minimize stress and fatigue 
    6. comfort level while reclining, and stress and anxiety related to the Procedures
    7. medication side effects such as dry mouth, and recommend treatment
    8. mouth ulcers and other conditions of the mouth relating to chemotherapy, comorbidities, complications or associated conditions, medications or diet
    9. pain and fever management with aspirin, acetaminophen and any other anti-pyretic medications.



  1. Promoting health through oral hygiene for persons who have received, are about to receive, or are receiving chemotherapy.
  2. Reducing the adverse effects, such as risks of infection and excessive bleeding associated with dental hygiene interventions by
    1. informed communication with the appropriate chemotherapy or treatment provider(s)
    2. generally increasing the comfort level of persons in the course of dental hygiene interventions 
    3. using appropriate techniques of communication
    4. providing advice on scheduling and duration of appointments.
  3. Reducing the risk of oral health needs being unmet. 


  1. Causing infection or excessive bleeding.
  2. Performing the Procedures at an inappropriate time, such as 
    1. without prior consultation with the treating physician
    2. for non-urgent oral healthcare during chemotherapy
    3. in the presence of complications for which prior medical advice is required
    4. in the presence of acute oral infection without prior medical advice.
  3. Disturbing the normal dietary and medications routine of a person with chemotherapy.
  4. Causing inappropriate management of pain medication. 






2011-12-01; 2016-02-16; 2021-05-10; 2024-03-20


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

Robert Farinaccia

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, 2016, 2021, 2024 College of Dental Hygienists of Ontario


1 Persons includes young persons and children