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Systemic Disorders and the Mouth


Rosalyn Sulyanto

, DMD, MS, Boston Children's Hospital

Reviewed/Revised Aug 2021 | Modified Sep 2022
Topic Resources

Clues suggesting systemic disease may be found in the mouth and adjacent structures (see Introduction to the Approach to the Dental Patient Introduction to the Approach to the Dental Patient A physician should always examine the mouth and be able to recognize major oral disorders, particularly possible oral cancers. However, consultation with a dentist is needed to evaluate patients... read more and table Oral Findings in Systemic Disorders Oral Findings in Systemic Disorders Oral Findings in Systemic Disorders ). A dentist should consult a physician when a systemic disorder is suspected, when the patient is taking certain drugs (eg, warfarin, bisphosphonates), and when a patient’s ability to withstand general anesthesia or extensive oral surgery must be evaluated.


Dental Care of Patients With Systemic Disorders

Certain medical conditions (and their treatment) predispose patients to dental problems or affect dental care.

Hematologic disorders

People who have disorders that interfere with coagulation (eg, hemophilia Hemophilia Hemophilias are common hereditary bleeding disorders caused by deficiencies of either clotting factor VIII or IX. The extent of factor deficiency determines the probability and severity of bleeding... read more , acute leukemia Acute leukemias Leukemia is a malignant condition involving the excess production of immature or abnormal leukocytes, which eventually suppresses the production of normal blood cells and results in symptoms... read more , thrombocytopenia Overview of Platelet Disorders Platelets are circulating cell fragments that function in the clotting system. Thrombopoietin helps control the number of circulating platelets by stimulating the bone marrow to produce megakaryocytes... read more Overview of Platelet Disorders ) require medical consultation before undergoing dental procedures that might cause bleeding (eg, extraction, mandibular block, tooth cleaning). Patients with hemophilia should have clotting factors given before, during, and after an extraction and restorative dentistry requiring local anesthesia (eg, fillings). Most hematologists prefer that patients with hemophilia, especially those who have developed factor inhibitors, receive infiltrative local anesthetics instead of blocks for restorative dentistry.

Restorative dentistry can be completed in a dental office after consultation with a hematologist; however, if the patient has inhibitor to factor VIII Factor VIII and Factor IX Inhibitors Circulating anticoagulants are usually autoantibodies that neutralize specific clotting factors in vivo (eg, an autoantibody against factor VIII or factor V) or inhibit phospholipid-bound proteins... read more , the dentistry should be done in a hospital under general anesthesia. Oral surgery should be done in the hospital in consultation with a hematologist. All patients with bleeding disorders should maintain a lifelong routine of regular dental visits, which includes cleanings, fillings, topical fluoride, and preventive sealants, to avoid the need for extractions.

Cardiovascular disorders

After a myocardial infarction, dental procedures should be avoided for 6 months, if possible, to allow damaged myocardium to become less electrically labile. Patients with pulmonary or cardiac disease who require inhalation anesthesia for dental procedures should be hospitalized.

Endocarditis prophylaxis is required before dental procedures only in patients with

  • Prosthetic cardiac valves or prosthetic material used for cardiac valve repair

  • Previous history of bacterial endocarditis

  • Unrepaired cyanotic congenital heart disease, including palliative shunts and conduits

  • Completely repaired congenital heart defect with prosthetic material or device (for 6 months after the procedure)

  • Repaired congenital heart disease with residual defects at the site or adjacent to the site of a prosthetic patch or prosthetic device

  • Cardiac transplantation recipients with a valvulopathy

The heart is better protected against low-grade bacteremias, which occur in chronic dental conditions, when dental treatment is received (with prophylaxis) than when it is not received. Patients who are to undergo cardiac valve surgery or repair of congenital heart defects should have any necessary dental treatment completed before surgery.

Although probably of marginal benefit, antibiotic prophylaxis is sometimes recommended for patients with hemodialysis shunts and within 2 years of receipt of a major prosthetic joint (hip, knee, shoulder, elbow). The organisms causing infections at these sites are almost invariably of dermal rather than oral origin.

Adrenergic drugs such as epinephrine and levonordefrin are added to local anesthetics to increase the duration of anesthesia. In some cardiovascular patients, excess amounts of these drugs cause arrhythmias, myocardial ischemia, or hypertension. Plain anesthetic can be used for procedures requiring < 45 minutes, but in longer procedures or where hemostasis is needed, up to 0.04 mg epinephrine (2 dental cartridges with 1:100,000 epinephrine) is considered safe. Generally, no healthy patient should receive > 0.2 mg epinephrine at any one appointment. Absolute contraindications to epinephrine (any dose) are uncontrolled hyperthyroidism; pheochromocytoma; blood pressure > 200 mm Hg systolic or > 115 mm Hg diastolic; uncontrolled arrhythmias despite drug therapy; and unstable angina, myocardial infarction, or stroke within 6 months.

Some electrical dental equipment, such as an electrosurgical cautery, a pulp tester, or an ultrasonic scaler, can interfere with early-generation pacemakers.


Extracting a tooth adjacent to a carcinoma of the gingiva, palate, or antrum facilitates invasion of the alveolus (tooth socket) by the tumor. Therefore, a tooth should be extracted only during the course of definitive treatment. In patients with leukemia or agranulocytosis, infection may follow an extraction despite the use of antibiotics.


Endocrine disorders

Dental treatment may be complicated by some endocrine disorders. For example, people with hyperthyroidism Hyperthyroidism Hyperthyroidism is characterized by hypermetabolism and elevated serum levels of free thyroid hormones. Symptoms include palpitations, fatigue, weight loss, heat intolerance, anxiety, and tremor... read more Hyperthyroidism may develop tachycardia and excessive anxiety as well as thyroid storm if given epinephrine. Insulin requirements may be reduced on elimination of oral infection in diabetics; insulin dose may require reduction when food intake is limited because of pain after oral surgery. In people with diabetes, hyperglycemia with resultant polyuria may lead to dehydration, resulting in decreased salivary flow (xerostomia Xerostomia Xerostomia is dry mouth caused by reduced or absent flow of saliva. This condition can result in discomfort, interfere with speech and swallowing, make wearing dentures difficult, cause halitosis... read more ), which, along with elevated salivary glucose levels, contributes to caries.

Neurologic disorders

Patients with seizures Seizure Disorders A seizure is an abnormal, unregulated electrical discharge that occurs within the brain’s cortical gray matter and transiently interrupts normal brain function. A seizure typically causes altered... read more who require dental appliances should have nonremovable appliances that cannot be swallowed or aspirated. Patients unable to brush or floss effectively may use 0.12% chlorhexidine rinses in the morning and at bedtime. In many countries outside the US chlorhexidine is available at 0.2%. However, this higher strength has not been shown to be more effective for gingival health and may cause increased tooth staining.

Obstructive sleep apnea

Patients with obstructive sleep apnea Obstructive Sleep Apnea (OSA) Obstructive sleep apnea (OSA) consists of multiple episodes of partial or complete closure of the upper airway that occur during sleep and lead to breathing cessation (defined as a period of... read more who are unable to tolerate treatment with a continuous positive airway pressure (CPAP) or bilevel PAP (BiPAP) mask are sometimes treated with an intraoral device that expands the oropharynx. This treatment is not as effective as CPAP, but more patients tolerate using it.


Certain drugs, such as corticosteroids, immunosuppressants, and antineoplastics, compromise healing and host defenses. When possible, dental procedures should not be done while these drugs are being given.

Many drugs cause dry mouth (xerostomia Xerostomia Xerostomia is dry mouth caused by reduced or absent flow of saliva. This condition can result in discomfort, interfere with speech and swallowing, make wearing dentures difficult, cause halitosis... read more ), which is a significant health issue, especially in geriatric patients. Causative drugs often have anticholinergic effects and include certain antidepressants, antipsychotics, diuretics, antihypertensives, anxiolytic and sedative drugs, nonsteroidal anti-inflammatory drugs (NSAIDs), antihistamines, and opioid analgesics.

Some antineoplastics (eg, doxorubicin, 5-fluorouracil, bleomycin, dactinomycin, cytosine, arabinoside, methotrexate) cause stomatitis Stomatitis Oral inflammation and ulcers, known as stomatitis, may be mild and localized or severe and widespread. They are invariably painful. (See also Evaluation of the Dental Patient and Gingivitis... read more Stomatitis , which is worse in patients with preexisting periodontal disease Periodontitis Periodontitis is a chronic inflammatory oral disease that progressively destroys the tooth-supporting apparatus. It usually manifests as a worsening of gingivitis and then, if untreated, with... read more Periodontitis . Before such drugs are prescribed, oral prophylaxis should be completed, and patients should be instructed in proper toothbrushing and flossing.

Drugs that interfere with clotting may need to be reduced or stopped before oral surgery. Patients taking aspirin, NSAIDs, or clopidogrel should stop taking them 4 days before undergoing dental surgery and can resume taking these drugs after bleeding stops. Most patients taking an oral anticoagulant who have a stable international normalized ratio (INR) < 4 do not need to stop the drug before outpatient dental surgery (including extraction) because the risk of significant bleeding is very small and the risk of thrombosis may be increased when oral anticoagulants are temporarily stopped. For people receiving hemodialysis Hemodialysis In hemodialysis, a patient’s blood is pumped into a dialyzer containing 2 fluid compartments configured as bundles of hollow fiber capillary tubes or as parallel, sandwiched sheets of semipermeable... read more , dental procedures should be done the day after dialysis, when heparinization has subsided.

Phenytoin, cyclosporine, and calcium channel blockers, particularly nifedipine, contribute to gingival hyperplasia. Gingival hyperplasia develops in about 50% of patients taking phenytoin and 25% of patients taking cyclosporine or a calcium channel blocker. However, hyperplasia is minimized with excellent oral hygiene and frequent cleanings by a dentist.

Bisphosphonates can result in antiresorptive agent-induced osteonecrosis of the jaw Medication-Related Osteonecrosis of the Jaw (MRONJ) Medication-related osteonecrosis of the jaw has no unanimously accepted definition or etiology but is generally held to be an oral lesion involving bare mandibular or maxillary bone present... read more (ONJ) after an extraction. ONJ occurs primarily when bisphosphonates are given parenterally to treat bone cancer and to a much lesser extent when they are taken orally to prevent osteoporosis (risk of ONJ about 0.1%). Diligent oral hygiene practices and regular dental care may help lower the risk of ONJ, but there are no validated techniques to determine who is at risk of developing antiresorptive agent–induced ONJ. Stopping bisphosphonate therapy may not lower the risk and may increase the rate of bone loss in people being treated for osteoporosis.

Radiation therapy

Extraction of teeth from irradiated tissues (particularly if the total dose was > 65 Gy, especially to the mandible) may be followed by osteoradionecrosis of the jaw, and thus should be avoided. This is a catastrophic complication in which extraction sites break down, frequently sloughing bone and soft tissue. In order to help avoid this potential complication, patients should have any necessary dental treatment completed before undergoing radiation therapy of the head and neck region, with time allowed for healing. Teeth that may not survive should be extracted. Necessary sealants and topical fluoride should be applied. After radiation, extraction should be avoided, if possible, by using dental restorations. Sometimes root canal therapy is done, and the tooth is reduced down to the gum line in order to prevent bone atrophy. If extraction is required after radiation, 10 to 20 treatments in a hyperbaric oxygen chamber may forestall or prevent osteoradionecrosis.

Pearls & Pitfalls

  • Osteoradionecrosis of the jaw sometimes follows extraction of teeth from irradiated tissues (particularly if the total dose was > 65 Gy, especially in the mandible). In this catastrophic complication, extraction sites break down, frequently sloughing bone and soft tissue. To avoid such a devastating complication, do any necessary dental work before the patient undergoes radiation therapy.

Head and neck radiation often damages salivary glands, causing permanent xerostomia Xerostomia Xerostomia is dry mouth caused by reduced or absent flow of saliva. This condition can result in discomfort, interfere with speech and swallowing, make wearing dentures difficult, cause halitosis... read more , which promotes caries Caries Caries is tooth decay, commonly called cavities. The symptoms—tender, painful teeth—appear late. Diagnosis is based on inspection, probing of the enamel surface with a fine metal instrument... read more Caries . Patients must therefore practice lifelong good oral hygiene. A fluoride gel and fluoride mouth rinse should be used daily. Rinsing with 0.12% chlorhexidine for 30 to 60 seconds, if tolerated, can be done in the morning and at bedtime. Viscous lidocaine may enable a patient with sensitive oral tissues to brush and floss the teeth and eat.

A dentist must be seen at 3-, 4-, or 6-month intervals, depending on findings at the last examination. Irradiated tissue under dentures is likely to break down, so dentures should be checked and adjusted whenever discomfort is noted. Early caries may also be reversed by calcium phosphopeptides and amorphous calcium phosphate, which can be applied by a dentist or prescribed to a patient for at-home use.

Patients who undergo radiation therapy may develop oral mucosal inflammation and diminished taste as well as trismus due to fibrosis of the masticatory muscles. Trismus may be minimized by such exercises as opening and closing the mouth widely 20 times 3 or 4 times/day.

Drugs Mentioned In This Article

Drug Name Select Trade
Coumadin, Jantoven
Adrenaclick, Adrenalin, Auvi-Q, Epifrin, EpiPen, Epipen Jr , Primatene Mist, SYMJEPI, Twinject
Betasept, Chlorostat, DYNA-HEX, Hibiclens, Oro Clense , Peridex, Periogard, PerioRx , Perisol
Adriamycin, Adriamycin PFS, Adriamycin RDF, Rubex
Adrucil, Carac, Efudex, Fluoroplex, Tolak
Jylamvo, Otrexup, Rasuvo, RediTrex, Rheumatrex, Trexall, Xatmep
Anacin Adult Low Strength, Aspergum, Aspir-Low, Aspirtab , Aspir-Trin , Bayer Advanced Aspirin, Bayer Aspirin, Bayer Aspirin Extra Strength, Bayer Aspirin Plus, Bayer Aspirin Regimen, Bayer Children's Aspirin, Bayer Extra Strength, Bayer Extra Strength Plus, Bayer Genuine Aspirin, Bayer Low Dose Aspirin Regimen, Bayer Womens Aspirin , BeneHealth Aspirin, Bufferin, Bufferin Extra Strength, Bufferin Low Dose, DURLAZA, Easprin , Ecotrin, Ecotrin Low Strength, Genacote, Halfprin, MiniPrin, St. Joseph Adult Low Strength, St. Joseph Aspirin, VAZALORE, Zero Order Release Aspirin, ZORprin
Dilantin, Dilantin Infatabs, Dilantin-125, Phenytek
Cequa, Gengraf , Neoral, Restasis, Sandimmune, SangCya, Verkazia, Vevye
Adalat, Adalat CC, Afeditab CR, Nifediac CC, Nifedical XL, Procardia, Procardia XL
7T Lido, Akten , ALOCANE, ANASTIA, AneCream, Anestacon, Aspercreme with Lidocaine, AsperFlex, Astero , BenGay, Blue Tube, Blue-Emu, CidalEaze, DermacinRx Lidocan III, DermacinRx Lidogel, DermacinRx Lidorex, DERMALID, Dologesic, Ela-Max, GEN7T, Glydo, Gold Bond, LidaFlex, LidaMantle, Lido King Maximum Strength, Lidocan, Lidocare, Lidoderm, LidoDose, LidoDose Pediatric, Lidofore, LidoHeal-90, LIDO-K , LidoLite, Lidomar , Lidomark, LidoPure, LidoReal-30, LidoRx, Lidosense 4 , Lidosense 5, Lidosol, Lidosol-50, LIDO-SORB, Lidotral, Lidovix L, LIDOZION, Lidozo, LMX 4, LMX 4 with Tegaderm, LMX 5, LTA, Lubricaine For Her, Lydexa, Moxicaine, Numbonex, ReadySharp Lidocaine, RectaSmoothe, RectiCare, Salonpas Lidocaine, Senatec, Solarcaine, SUN BURNT PLUS, Tranzarel, Xyliderm, Xylocaine, Xylocaine Dental, Xylocaine in Dextrose, Xylocaine MPF, Xylocaine Topical, Xylocaine Topical Jelly, Xylocaine Topical Solution, Xylocaine Viscous, Zilactin-L, Zingo, Zionodi, ZTlido
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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