Clinical Scenario

A 47‐year‐old male is referred for urgent dental assessment by his haemato‐oncology specialist. The patient complains of recurrent pain from a tooth in the upper left quadrant which is typically present 1 week after chemotherapy and then subsides.

Structured Learning

1. What is the significance of the patient taking imatinib?
   • Imatinib is a targeted cancer therapy drug (biological therapy)
   • It acts as a tyrosine kinase inhibitor, thereby blocking the growth of cancer cells
   • It is taken orally once or twice a day
   • In addition to the general side‐effects of cancer therapy, it has been implicated in the development of medication‐related osteonecrosis of the jaw (MROJ)

   

   

2. What could be the cause of the lesion in the left buccal mucosa?
   • The patient chews paan which is typically composed of areca nut, slaked lime (from limestone or coral) and tobacco wrapped within a betel leaf
   • This is known to be associated with yellow‐brown staining of the teeth and mucosal surfaces, the development of white patches (leucoplakia) and oral submucous fibrosis (associated with the areca nut)
3. You advise the patient to stop chewing the paan due to the negative impact on his oral health and the risk of oral cancer. He advises you that it helps him to cope with his chemotherapy and manage his diabetes. What could be the perceived benefits he is referring to?
   • Paan is perceived as a cure for halitosis
   • It is also used by some patients to manage symptoms such as nausea and vomiting associated with chemotherapy
   • Some patients with diabetes also believe that paan helps control the disease
   • However, the perceived health benefits are not proven
   • The risks of continued paan use, particularly when it contains areca nut and tobacco, outweigh any possible benefits
4. Sensibility testing is undertaken on #26 and #27. Both teeth are confirmed to be non‐vital. The patient requests root canal treatment as he does not want to lose more teeth. What would you discuss?
   • If the teeth are restorable, endodontic treatment followed by restoration and a full‐coverage restoration at a later stage is an option
   • However, consideration should be given to the fact that the patient is receiving active chemotherapy to control his CML
   • Completion of multiroot endodontic treatment and restoration is likely to cause further delays to chemotherapy
   • Furthermore, although the success rate of root canal treatment is 90–95%, a risk of reinfection remains which can cause further delays
   • As the patient is immunocompromised due to both CML and cancer therapy, the success rate is likely to be lower
   • This can pose a further risk during chemotherapy and delay treatment further due to the potential for bacteraemia
5. Following discussion with the haemato‐oncologist, dental extraction of #26 and #27 is advised. What factors would you need to take into account?
   • It is ideal to wait at least 10 days post dental extractions before recommencing chemotherapy (to allow for primary healing); hence the next cycle of chemotherapy may need to be delayed (risks and benefits of this should be discussed with the haemato‐oncologist)
   • Increased risk of bleeding, infection and delayed wound healing
   • This would then need to be followed by further close reviews due to the risk of MRONJ
6. Preoperative blood tests confirm the Hb level is 100 g/dL, platelets 65 × 10⁹/L and neutrophil count 0.5 × 10⁹/L. What are the implications for dental extractions given these blood counts (see Chapter 12.2)?
   • The Hb count is reduced, indicating that the patient is anaemic; this is associated with hypoxia, lethargy and fatigue; supplemental nasal oxygen at 2–3 L/min should be considered during dental extractions
   • Although the platelet levels are low, they are sufficient to proceed with dental extractions under local anaesthesia without platelet supplementation; local haemostatic measures should be used, including sutures and haemostatic agents (sponges and tranexamic acid mouthwash)
   • The neutrophil count is significantly reduced; this is associated with a significant risk of infection; perioperative antibiotic prophylaxis and granulocyte‐colony stimulating factor (G‐CSF) subcutaneous injections typically given for 5 days prior to surgery, may be advised by the haemato‐oncologist; G‐CSF stimulates the bone marrow to produce more white blood cells, although it is used with caution as it may stimulate some leukaemic processes; it is currently considered as a safe and effective way to stimulate myelopoiesis and allows for continued imatinib therapy in CML patients at risk for disease progression
7. What other factors do you need to consider in your risk assessment?
   • Social
     • Patient is likely to be fatigued due to CML and chemotherapy
     • An escort is desirable
     • When scheduling dental appointments, need to consider the timing and impact of the cancer therapy hospital visits
   • Medical
     • Anaemia, thrombocytopenia and neutropenia are common side‐effects of CML treatment
     • Caution when interpreting the haemoglobin A_1c levels as anaemia in relation to chemotherapy and/or cancer therapy (anaemia may exaggerate the glycaemic status of the patient)
   • Dental
     • Acute and chronic side‐effects of chemotherapy
     • Risk of MROJ
     • Calorific supplement drinks and soft diet increase caries risk
     • Suboptimal oral hygiene habits
     • Compliance issues in daily life
     • Lack of perceived need
     • Irregular dental attender
     • Xerostomia due to chemotherapy and diabetes
     • Increased risk of periodontal disease due to diabetes (bidirectional relationship)
     • Food packing
     • Paan‐associated risk of oral submucous fibrosis

General Dental Considerations