Drugs Used In Dentistry Question and Answers

Drugs Used In Dentistry Short Notes

Question 1. Antihistamines
(or)
Cetirizine.
Answer:

• Cetirizine is an antihistamine drug used in dentistry to manage acute allergic conditions like allergic stomatitis.
• The drug metabolite competes with histamine for H1 receptors and reduces the histamine response.

Antihistamines Dosage:

• For adults: 5-10 mg once a day
• For children (2-5 years): 5 mg once a day
• Adverse effects: Headache, fatigue, abdominal pain, drowsiness, pharyngitis
  • The drug should be avoided in patients taking anticholinergics and CNS depressants.

Read And Learn More: Oral Medicine and Radiology Question And Answers

Question 2. Saliva substitutes.
Answer:

• Artificial saliva provides symptomatic relief for patients with dry mouth due to minimal salivary gland function.
• Artificial saliva is composed of buffering agents, cellulose derivatives, and flavoring agents. Cellulose increases the stickiness and aids in moistening capacity.

Saliva substitutes Merits: It enhances the patient’s comfort by enhancing speech, mastication, and swallowing actions.

Saliva substitutes Demerits:

• The composition of real saliva contains enzymes, immunoglobulins (salivary IgA), antimicrobial proteins, and minerals.
• These substances are not present in artificial saliva. So, synthetic saliva cannot overcome the effects of reduced salivary flow like increased caries risk and oral infections.

Question 3. Pilocarpine.
Answer:

• Pilocarpine hydrochloride is a systemic sialo- gogue used in the treatment of xerostomia. It is a parasympathetic drug and stimulates exocrine glands.
• In the salivary gland, it acts by stimulating acinar cells with some residual functioning effects.
• Pilocarpine Dose: 5-10 mg, three times a day. The action starts in 30 minutes, the maximum effect is achieved by 1 hour, and the effects persist for 2-3 hours approximately.
• Pilocarpine Side effects: Gastrointestinal irritation, sweating, tachycardia, bradycardia, and blurred vision.
• Pilocarpine Contraindications: Patients with heart diseases, asthma, glaucoma, renal diseases, gallbladder disease, and chronic obstructive pulmonary disease.

Question 4. Orabase.
Answer:

• Orabase is a protective agent for oral mucosa. It stays in close contact with oral mucosa for a sufficient time and therefore protects the lesion site from irritations associated with routine activities like speech and mastication.
• Also acts to prevent secondary infection by forming a protective barrier over the lesion.
• It is composed of gelatin, pectin, and sodium carboxymethylcellulose in a plastic base (plasticized hydrocarbon gel). It is non¬irritating and biocompatible.
• Orabase Indication: Aphthous ulcer, traumatic ulcer, chemical burn.

Question 5. Topical immunomodulators for oral lesions.
Answer:

Tacrolimus:

• Tacrolimus is a fungus-derived immuno-suppressant and is used as a topical ointment for the autoimmune disorder of the oral cavity, such as pemphigus, pemphigoid, lichen planus, psoriasis, desquamative gingivitis, and Crohn’s disease.
• Tacrolimus is a calcineurin inhibitor that inhibits T-helper lymphocyte activation. Calcineurin is responsible for immune response.
• Tacrolimus inhibition of calcineurin leads to inhibition of IL-2 and other pro-inflammatory cytokines, such as IL-4 and -IL-5.
• The result is a failure in the differentiation of inflammatory cells, such as T-lymphocytes, eosinophils neutrophils, and suppression of their action.

Cyclosporine:

• Topical cyclosporine A (CSA) is used in the treatment of oral lichen planus, major aphthous ulcer, pemphigus, pemphigoid, and lichenoid reaction.
• CsA is a polypeptide derived from fungal extracts and selectively inhibits cytokines and the functions of T-cell lymphocytes.
• CsA binds with cyclophilins (cellular cytoplasmic proteins), forming a complex that binds to and inhibits calcineurin. The result is the inhibition of T-helper cell activation and suppression of the proinflammatory cytokines release (IL-2, IL-3, IL-4, CD40L, GM-CSF, TNF-a, and IFN-g), inhibition of T-suppressor and T-cytotoxic cells.

Question 6. Topical corticosteroids.
Answer:

• Topical corticosteroids are primarily used to treat oral mucosal lesions of autoimmune disorders (like lichen planus, pemphigus, and pemphigoid), oral submucous fibrosis, a hypersensitive reaction like erythema multi¬forme and inflammatory conditions like major and herpetiform aphthous ulcers.
• In these conditions, topical steroids are used alone or in combination with systemic steroids.
• Topical steroids are available in three different potentials. Based on the severity of lesion the potency of the drug is selected.

Mild Potent Drugs:

• Triamcinolone acetonide 0.1% cream
• Fluocinolone acetonide 0.025% cream, ointment
• Betamethasone 0.05% cream

Moderate Potential Drugs

• Fluocinonide 0.5% cream
• Desoximetasone 0.25% cream

High Potency Drugs:

• Clobetasol propionate 0.5% ointment
• Betamethasone valerate 0.05% cream.

Question 7. Analgesics
(or)
NSAIDs in dental practice.
Answer:

• Nonsteroidal anti-inflammatory drugs are indicated for pain control.
• They inhibit COX-2 and COX-1 enzymes or selectively inhibit COX-2 alone. (Pain is mediated by prostaglandins which depend on COX-1 and COX-2 actions).
• Many NSAIDs are not only analgesic but also possess anti-inflammatory and antipyretic properties.
• Ibuprofen is the frequently prescribed analgesic in dentistry which is administered at 200 or 400 mg, every 4-6 hours, for a maximum dose of 1200 mg/day. But the major adverse effect associated is a gastric ulcer and bleeding in chronic use.
• Selective COX-2 inhibitors are advantageous in reducing the chances of gastric ulcers and bleeding but less effective than Ibuprofen.
• When prescribing analgesics, NSAIDs should be avoided for patients with a history of asthma, renal disorders, and gastric ulcer. It is strictly contraindicated for pregnant women in the 3rd trimester.
• In such contraindicated conditions, acetaminophen should be the drug of choice. Acetaminophen is free of NSAID side effects and possesses analgesic and antipyretic properties but not anti-inflammatory, at the dose of 500-1,000 mg, 4-6 hourly to a maximum dose of 4 g/day.

Drug interactions:

• NSAIDs reduce the effect of ACE inhibitors, diuretics, and P-blockers in anti-hypertensive patients.
• NSAIDs cause hypoglycemia in diabetic patients taking oral hypoglycemics.
• NSAIDs reduce the effect of warfarin.

Question 8. Opioids.
Answer:

• In the case of managing moderate to severe pain, like pain due to oral cancer, severe trauma, and multiple fractures of facial bones (due to road traffic accidents), and in postsurgical care, opioids are considered in dental practice.
• They are centrally-acting drugs with peripheral anti-inflammatory properties.
• The potential side effects include drug dependence, sedation, respiratory depression, nausea, vomiting, and constipation.
• The recommended oral dosage:
  • Morphine 100 mg/day, codeine 60 mg/ day
• To reduce the side effects, they can be combined with NSAIDs.

Question 9. Carbamazepine.
Answer:

• Carbamazepine is an anticonvulsant drug. Carbamazepine (200-1,200 mg/day) and oxcarbazepine (600-1,800 mg/day) are the most prescribed drugs for treating trigeminal neuralgia.
• Their analgesic action is by the sodium channel blockage. This occurs either by stabilization of hyperexcited neuronal mem-branes, controlling the recurrent firing or by decreasing the synaptic impulses.
• Initial therapy for pain control should be started with 100 mg two to three times a day, and then gradually increased by 100 mg every other day until adequate pain relief is established. Maintenance doses range from 300-800 mg/ day divided into two to three daily doses.
• Initial side effects include drowsiness, nausea, dizziness, diplopia, ataxia, and hypo-natremia. Potentially serious side effects are allergic rash, myelosuppression, hepato- toxicity, lymphadenopathy, Stevens-Johnson syndrome, and aplastic anemia.

Question 10. Capsaicin.
Answer:

• Capsaicin is the component of hot chili pepper. This compound is used in a topical form for the management of postherpetic neuralgia. When applied topically, it results in the excitation of nociceptive afferent fibers. The frequent application of capsaicin results in the desensitization of unmyelinated nerve fibers and pain control.
• Low-concentration (0.025 or 0.075%) capsaicin topical creams are efficient in the pain management of postherpetic neuralgia.
• High-concentration (8%) synthetic capsaicin dermal patches are also available to provide fast and persistent pain relief following a single application. Adverse effects at the application site include erythema and burning sensation.

Question 11. Topical antiviral drugs.
Answer:

• Topical antiviral treatments are used for managing the symptoms rather than treating oral herpes lesions (recurrent herpes labialis).
• They are effective in reducing the symptoms (itching, tingling burning sensation, and pain), the duration of viral shedding, and the healing period for ulcers. They also reduce the number of recurrent episodes.
• The topical forms available for oral use include Acyclovir cream 5% and penciclovir cream 1%. Rapid healing and pain relief are possible when applying penciclovir cream at the prodromal period (erythema stages) and then start applying at the papule and vesicle stages of the lesion.
• The cream should be applied every 2 hours in the daytime for 4 days.

Question 12. Topical antifungal drugs.
Answer:

• The purpose of using topical forms of anti-candidal medication is to enhance the drug’s effectiveness through direct contact of the drug with the lesion.
• Topical antifungal treatment is mandatory for a minimum of 2 weeks to eradicate the infection. But the symptom resolution occurs 3-4 days after application.
• Nystatin is a polyene antifungal anti¬biotic. Sterols are the component of the plasma membrane of the fungus cells. The antifungal effect of nystatin is due to its physicochemical interaction with sterols resulting in the production of aqueous pores on the cell membrane leading to increased permeability, leakage of cytoplasmic contents, and death of the organism.
• It is the most frequently used topical medication for oral candidiasis. Nystatin preparation includes oral rinse, pastille, and suspension forms.
  • Nystatin oral suspension (100,000 U/ mL)—patient needs to rinse 4-6 mL/per dose for 2 minutes and expectorate, four times/day for 2 weeks.
• Ergosterol is a constituent of the fungal cytoplasmic membrane. Clotrimazole interferes with the biosynthesis of ergosterol and provides fungicidal effects.
  • Clotrimazole (10 mg oral troches): Dis-solve one troche in the oral cavity five times a day.

Question 13. Tricyclic antidepressants.
Answer:

• Antidepressants are used in the management of many chronic pain conditions, even though depression is not caused or precipitating reason. The typical conditions include myo¬fascial pain dysfunction syndrome, atypical facial pain, postherpetic neuralgia, diabetic neuropathy and TMJ disorders especially associated with parafunctional habits.
• When the patient is suffering from chronic facial pain, there may be an associated state of depression and altered sleep patterns. These conditions further worsen the pain experience. In the presence of parafunctional habits (bruxism), tricyclic antidepressants (TCAs) may bring about muscle relaxation effects.
• The analgesic action of tricyclic anti-depressants is by blocking the reuptake of serotonin and norepinephrine. This blockade enhances the inhibition of spinal cord neurons involved in pain perception. Pain relief is not an immediate effect and takes several weeks for sufficient control.
• The commonly used antidepressants include amitriptyline (10-30 mg/day), imipramine, clomipramine, nortriptyline, and desipramine.

Question 14. Interferons.
Answer:

• Interferons are proteins belonging to the cytokine group and possess immunomodulatory, antiviral, and antiproliferative activities.
• There are three types: Alpha, beta, and gamma. Alpha interferons have 24 subtypes, whereas beta and gamma interferons have one subtype each.
• In dentistry, interferons are used in the management of oral premalignant and malignant lesions.
• They bind to specific receptors on the cell surface and exert their effects.
• Antiviral activity: IFNs act in the viral target cells by either blocking or impairing the viral replication by synthesizing of enzymes that interfere with the cellular and viral processes.
• Anticancer effect: They exert an antiproliferative effect on cancer cells and cause stasis of tumor growth by inducing certain enzymes.

Question 15. Magic mouthwash.
Answer:

• “Magic mouthwash” is a unique preparation prescribed for oral mucositis induced by chemotherapy or radiotherapy, major aphthous stomatitis, and other mucosal ulcerations. Magic mouthwash is prepared by a mixture of medications to treat oral mucositis and ulcers.
• The following medications can be used in combination and preferably any three components can be used as per requirement.

Antibiotic (to inhibit the microbial colonization):

1. Antihistamine (to control local allergic reactions)
2. Antifungal (to prevent secondary fungal growth)
3. Steroid (to suppress inflammation)
4. A local anesthetic agent (pain relief), and
5. An antacid (to enhance the coating of the ingredients).

Other preparation includes topical anesthetics, such as lidocaine, viscous diphenhydramine, and Maalox (aluminum/magnesium hydroxide) to enhance the adhesion of the ingredients in the mouth.

Question 16. Adverse effects of corticosteroid therapy.
Answer: Long-term steroid (glucocorticoids) therapy is associated with:

• Hypertension is caused by renal sodium retention and increased response to angiotensin 2 and catecholamines.
• Inhibition of osteoblast formation leads to osteoporosis by bone fracture.
• Delayed wound healing due to the synthesis of matrix metalloproteinases and collagen.
• It promotes gluconeogenesis and inhibits protein degradation and lipolysis leading to hyperglycemia.
• Gastrointestinal bleeding and peptic ulcer.
• Immunosuppression and reactivation of viral infection.
• In children, extended use may lead to growth retardation.
• Prolonged topical application of oral mucosa may lead to tissue atrophy and a burning sensation.
• Steroid inhalation and topical application may lead to opportunistic candidal infection.

Drugs Used In Dentistry Viva Voce

Question 1. Amifostine.
Answer:

• It has cytoprotective and radioprotective effects on the salivary gland.
• It is used for patients undergoing head and neck radiation therapy.
• 4 route administration of the drug before radiotherapy.

Question 2. What are immunomodulators?
Answer: Immunomodulators are the drugs that modify the immune reaction by either enhancing (immunostimulators) or reducing (immuno- suppressors) the production of antibodies.

• Immunosuppressive drugs are used to treat autoimmune diseases, such as graft-versus-host, pemphigus, pemphigoid, or lichen planus.
• Immunostimulants are used to increase, the immune response to immunodeficient conditions (like AIDS) and malignancies.

Question 3. Name a few bacteriostatic antibiotics used in dentistry.
Answer: Tetracycline, erythromycin, and clindamycin.

Question 4. What is pseudomembranous colitis?
Answer:

• The use of broad-spectrum antibiotics (like penicillin—especially ampicillin, erythromycin, and cephalosporin) alters the gut ecology and leads to the overgrowth of Clostridium difficile.
• C. difficile and its toxins cause pseudomembranous colitis characterized by diarrhea and abdominal pain, hence otherwise known as antibiotic-associated diarrhea.
• The broad-spectrum antibiotic should be immediately discontinued and metronidazole 400 mg, three times/day for 7-14 days should be started to treat this condition.

Question 5. What are the requirements for antibiotic prophylaxis?
Answer:

• Dental patients reporting with a history of infective endocarditis, prosthetic heart valves, valvular heart disease, cardiac transplantation, congenital cardiac disorders, and total joint replacement should be considered for antibiotic prophylaxis to provide specific dental treatments.
• Prophylaxis is not required for patients with pacemakers and implanted defibrillators, and previous history for coronary bypass surgery.

Question 6. What are the dental procedures that require antibiotic prophylaxis in susceptible patients?
Answer: Dental extraction, periodontal surgeries, endodontic procedures involving beyond the apices, placement of orthodontic bands, reimplantation of avulsed teeth, subgingival placement of cords or fibers, intraligamentous injections, teeth polishing and implant procedure with bleeding.

Question 7. What is the half-life of a drug?
Answer:

• The half-life of a drug is the time taken for the drug to achieve a plasma concentration of 50% from the initial concentration.
• The clinical significance is half-life is to calculate the drug administration frequency like doxycycline with a half-life of 20 hours is administered once in 24 hours to achieve target concentration.
• Drugs with very short life are administered intravenously.

Question 8. What are the action and indications for bisphosphonates?
Answer:

• Bisphosphonates are effective in inhibiting b bone resorption by impairing the blood supply and reducing the action of osteoclasts.
• They are indicated in the management of osteoporosis, Paget’s disease, multiple myeloma, metastatic cancers, and for patients taking long-term corticosteroid therapy.
• Their main adverse effect is osteonecrosis of jaw bones.

Question 9. Amlexanox.
Answer:

• Amlexanox is a topical anti-inflammatory and antiallergenic drug used for the treatment of aphthous stomatitis. In the concentration of 2-5% application, they reduce the ulcer size and healing period.
• Amlexanox is a pyridochromene and monocarboxylic acid derivative.

Question 10. Topical metronidazole.
Answer:

• Metronidazole is an antibiotic effective against gram-negative anaerobic organisms. It acts by inhibiting the synthesis of DNA and by oxidation-induced degradation to break the single and double strands of DNA and cell death.
• The topical form is available as 25% metronidazole gel and is effective in antimicrobial properties due to the high concentration at the lesion site. The topical form is indicated in the treatment of dry socket, periodontitis, and peri-implantitis.

Question 11. What is Reye’s syndrome?
Answer:

• The administration of aspirin in children at the recovery stage of viral infection (like chickenpox or flu) causes a severe condition characterized by a reduction in blood glucose, a rise in blood ammonia level, and plasma acidic pH.
• The symptoms include diarrhea, vomiting, tachypnea, lethargy, seizures, convulsions, and loss of consciousness. It is a serious condition and needs immediate medical care.

Drugs Used In Dentistry Highlights

• Prescribing drug is a routine act in dental practice. Dental students should acquire adequate knowledge about the commonly prescribed drugs, modes of action, drug interactions, and safety measures.
• Before prescribing, it is necessary to review the medical condition, concurrent medications taken by the patient for other illnesses, and drug allergies. Also, underdosing and overdosing should be avoided as they develop drug resistance and drug toxicity, respectively.
• This chapter focuses on the relevant drugs prescribed in dental practice with drug regimens and dosages.