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Table 4: Normal Complete Blood Count Type of Cell Age of Patient

Table 5: Differential White Blood Cell Count Type of White Blood Cell Normal Results Neutrophils (PMNs)

Normal Range

White blood cells

1–3 years

6.0–17.5 cells/mm 3

40%–60% (3,000–6,000/mm 3 )

4–7 years

5.5–15.5 cells/mm 3

Neutrophils (Bands)

0%–3% (0–300/mm 3 )

8–13 years

4.5–13.5 cells/mm 3

Eosinophils Basophils Lymphocytes Monocytes

1%–4% (50–400/mm 3 )

13 years–adult

4.5–11.0 cells/mm 3

0.5%–1% (15–50/mm 3 )

Note. Adapted from Medline, U.S. National Library of Medicine. 202 2. CBC blood test . https://medlineplus.gov/ency/ article/003642.htm

20%–40% (1,200–3,000/mm 3 )

2%–8% (100–600/mm 3 ) Absolute neutrophil count (ANC) = WBC × (%PMNs + %Bands). Consider antibiotic prophylaxis if ANC is <1,000/mm 3 . Note. Adapted from National Institutes of Health, U.S. National Library of Medicine. (2023). Blood differential . https:// medlineplus.gov/ency/article/003643.htm of radiation, and lack of collateral circulation. Before treating a patient who has had head and neck radiation, it is critical to obtain information from the radiation oncologist regarding the field of radiation and the specific dose to the bone (Brook, 2020). In addition to the complications mentioned, prepubescent pediatric patients undergoing radiation treatment or chemotherapy may have abnormal craniofacial and dental development. Corrective surgery can be considered when the patient reaches adulthood. Dysgeusia (altered taste), swallowing difficulties, and speech impairment are also possible consequences of radiation and chemotherapy. Patients undergoing chemotherapy with vincristine or vinblastine may develop transient neurotoxicity. This condition can mimic pulpitis (nerve inflammation in the teeth). Chemotherapeutic agents can affect platelet function as well as production of clotting factors that are made in the liver. Because of the extreme oral complications that can occur in this population, patients must receive a pretreatment dental evaluation. Early treatment of oral infections can minimize the risk of systemic infections when the patient is myelosuppressed. Minimizing oral pain will help the patient maintain nutrition throughout the active cancer treatment phase and beyond. If extractions are indicated, it is important that surgery is performed at least 2 weeks prior to initiation of head and neck radiation, and 10 days prior to initiation of chemotherapy. Balancing protective and risk factors by means of a caries risk assessment is a helpful tool for managing oral health and preventing dental disease. Cancer patients present with the highest risk for developing caries and the highest risk for the systemic manifestations of oral disease, making prevention of great significance. Increasing protective factors by means of additional fluoride, other remineralizing agents, or diet modifications must be made patient-specific by tailoring them to the needs of each individual and family. There are some special considerations for the patient receiving a hematopoietic stem cell transplant (bone marrow transplant). The risk of xerostomia, infection, severe bleeding, and oral ulceration or mucositis is considerably higher because of the intensive immunosuppressive conditioning regimen such a patient is experiencing.

Dental treatment implications Oral mucositis is characterized by damage to the epithelium of the oral mucosa, which can include the cheeks, tongue, palate, and oropharynx. Oral mucositis is graded on a scale of 1 to 4, with Grade 1 characterized by soreness and erythema (reddening) and Grade 4 characterized by extreme pain and sloughing of the mucosa. In radiation therapy, mucositis develops as early as 6 to 10 days after the beginning of treatment and resolves a month or so after treatment. In chemotherapy, mucositis is less severe, takes longer to develop, and resolves more quickly. In the patient undergoing radiation, severe mucositis necessitates reduction or cessation of therapy 35% of the time (Soutome et al., 2021). Mucositis has a variable presentation that requires multiple treatment modalities. There are many types of proprietary palliative treatments available to decrease pain associated with mucositis. One is called, which provides a temporary protective coating to the mucosal tissues. It is important to be able to distinguish oral mucositis from traumatic ulcers, erosive lichen planus, apthous ulcers, herpetiform lesions, erythematous candidiasis, vesiculo bullous lesions, and other oral soft tissue pathology. The development of oral lesions in proximity to radiation or chemotherapy should help inform the clinician accordingly (Mazhari et al., 2019; Razmara & Khamamzadeh, 2019; Shetty et al., 2022). Radiation therapy via external beam may be done with or without chemotherapy. The oral effects are more severe when the patient undergoes therapy for head and neck tumors than for total body irradiation for hematopoietic (blood-related) diseases. Dosing is measured in centigray (cGy). A dose of 3,000 to 4,000 cGy is sufficient to permanently damage salivary glands and cause fibrosis of the soft tissues of the head and neck. This damage can cause severe xerostomia and trismus (limited opening of the jaw), which can become a permanent condition. Full-dose radiation in the range of 7,000 to 7,500 cGy can damage the fine vasculature of the jaws, particularly in the mandible. The most severe complication in this situation is called osteoradionecrosis . In this situation, hypoxia (low oxygen levels), hypovascularity (low vascularity), and hypocellularity (low cellular count) set the condition for the body’s inability to heal bone when an extraction is done. The mandible is more susceptible than the maxilla to osteoradionecrosis because of the mandible’s higher density, higher absorption

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