period for observation of the hemostatic response. For vWD type 2B and type 3 or patients who do not respond to desmopressin, vWF replacement therapy is required. Platelet disorders can be divided into two major categories: thrombocytopenia, which affects quantity and results in too few platelets, and thrombasthenia, which affects quality, leading to dysfunction of platelets (Little et al., 2018). Thrombocytopenia results when blood vessel disorders, drug interactions, or autoimmune disorders destroy platelets. Treatments that should be considered include platelet infusion in patients who are at high risk. A platelet count of 100,000/mL is the minimal level required for major surgery and bony extractions, while minor surgery that will result in only superficial wounds can be performed with platelet counts of around 50,000/mL. Thrombasthenias are rare disorders and result from defects in adhesion receptors required for platelet activation and aggregation. The most commonly seen oral signs in patients with platelet disorders are petechiae and ecchymosis of the hard and soft palate (Little et al., 2018). Besides the systemic control of bleeding described above, local therapy using hemostatic agents may also be useful if excessive postoperative bleeding occurs after an extraction or surgery. Products like Gelfoam, an absorbable gelatin sponge made from purified gelatin solution that absorbs for 3 to 5 days, are helpful in patients taking antithrombin agents. Surgicel is another local therapy, made of oxidized regenerated cellulose that swells upon blood contact and results in pressure that promotes hemostasis. Another useful local agent is microfibrillar collagen, commercially known as Avitene , which works to attract platelets and trigger aggregation (Little et al., 2018). It is crucial for the dentist to maintain open and clear communication with the patient’s caregivers and physician or hematologist to ensure the safety of the patient. Possession of a comprehensive medical history, consultation with the patient’s physician, and awareness of current hematologic values are the standard of care for these medically compromised patients. The dentist should also be prepared for intraoperative management via local modalities as well as postoperative bleeding. Surgical techniques may be modified to minimize trauma. In most cases, once the bleeding disorder is identified, steps can be taken to greatly reduce the risks associated with dental procedures. Self-Assessment Quiz Question #2 Patients with bleeding disorders are leading longer, more productive lives. Which of the following is true regarding the dental implications of bleeding disorders? a. Drug-induced coagulation abnormalities occur in patients using warfarin or heparin under anticoagulation therapy. b. Nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen also inhibit COX, and the effect is irreversible. c. Microfibrillar collagen, commercially known as Avitene , works to attract fibrin and triggers coagulation. d. Little clinical value is to be obtained from a patient with a history of bleeding disorders prior to dental treatment.
result of an immune response (Arruda et al., 2018). These inhibitors are usually immunoglobulin G (IgG) antibodies. They are often seen in patients with severe hemophilia and are more common with hemophilia A. The development of inhibitors poses a challenge for treatment because simple factor replacement can be ineffective, and these patients must be treated with alternative bypassing agents such as recombinant factor VIIIa to promote hemostasis. Immunosuppressive drugs may also be needed to reduce antibody titers. As can be the case with hemophilia, desmopressin acetate is included in the treatment for vWD type 1, type 2A, and type 2M. Desmopressin is a synthetic vasopressin analogue (Punjadath et al 2022), which can stimulate release of vWF stored in endothelial cells and thereby raise plasma levels of vWF and functional factor VIII for 8 to 12 hours, improving primary hemostasis. Desmopressin can be administered intravenously, subcutaneously, or as an intranasal spray. Patients considered for desmopressin therapy will need a trial Dental treatment implications Drug-induced coagulation abnormalities occur in patients using warfarin or heparin under anticoagulation therapy. Such patients are at increased risk for bleeding with trauma or surgical procedures. Warfarin is the most widely used anticoagulant in the U.S. and works by inhibiting the biosynthesis of vitamin K–dependent coagulation proteins; factors VII, IX, and X; and prothrombin. Warfarin binds to albumin, is metabolized by the liver, and is excreted in the urine. The INR is employed to monitor warfarin’s effect. The INR value normally maintained is between 2.0 and 4.0, and the risk of bleeding increases as the INR rises. Current recommendations for the management of patients on warfarin include preoperative check of INR within 72 hours of invasive dental procedures. In addition, dentists should not instruct a patient to stop their warfarin without careful consideration because the patient may be placed at significant increased risk of a thrombotic event. It is safe to proceed with invasive dental procedures if the INR is equal to or less than 4, with special precautions taken to minimize trauma (Rodriguez et al., 2023). Heparin A is a proteoglycan that acts as a cofactor to antithrombin III, a naturally occurring anticoagulant. It speeds up the inhibition of serine proteases of the coagulation cascade, especially factors IIa and Xa and thrombin. Heparin is monitored by the thromboplastin time aPTT. It is used in high doses to treat thromboembolism and in low doses as prophylaxis for thromboembolism (Dingus et al., 2022). Certain drugs can hinder platelet activity. The most common is aspirin, which acetylates cyclooxygenase (COX), which blocks thromboxane A2 (TXA2) release from activated platelets and has an irreversible effect on platelets. Nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen also inhibit COX, but the effect is reversible. Therefore, postoperative pain control should be maintained with minimal doses of acetaminophen, with or without codeine. Aspirin and the other NSAIDs must be avoided for these patients (Guin, 2023). The usual treatment for platelet disorders is infusion of packed platelets just prior to surgery.
CRANIOFACIAL ABNORMALITIES
Craniofacial abnormalities are a group of disorders that affect the growth, development, form, function, and positioning of the tissues of the jaw, mouth, and head.
Approximately 28 conditions have been identified as unique craniofacial disorders, although combinations of these conditions account for many more. In the U.S., roughly 1
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