Pharmacology Third Year

1. 1
Astringents, Keratolytics, Anti-seborrhics
Enzymes
(hyaluronidase, varidase, trypsin & chymotrypsin)
Obtundants, Mummyfying agents & fluorides
Treatment of common oral diseases

2. 2
Astringents
• These are locally applied protein precipitants
• Action limited to cell surface or interspaces
• Membrane permeability is reduced, cells remain viable
• Actions & uses:
• Form a protective layer, prevent irritation & m.o. entry
• Control bleeding, local hemostatic action
Reduce inflammation, prevent exudation from capillaries
∀ ↓ sweating (anti-perspirant action); block sweat ducts
• Promote healing
• Adverse effects:
• Many astringents are irritants or caustics in high doses
• Can cause redness, pain & ulceration

3. 3
Astringents (Cont.)
• Metallic astringents:
• Aluminum compounds: Al acetate, Al chloride
• Zinc compounds: Zn oxide, Zn chloride
• Calamine: Iron oxide with Zn oxide
• Others: Silver nitrate, potassium permanganate
• Vegetable astringents: Tannic acid

4. 4
Keratolytics
• Drugs that facilitate removal of outer layer of skin
(stratum corneum) are called keratolytics
• Salicylic acid, benzoyl peroxide, tretinoin
• Uses:
• Hyperkeratosis
• Fungal skin infections (along with anti-fungal drugs)
• Acne vulgaris (along with antibacterial drugs)

5. 5
Anti-seborrhics
• Seborrhea is a chronic skin condition, due to over
activity of epidermis & sebaceous glands
• Greasy crusty scales are formed behind ears, on face,
neck.
• Dandruff is the commonest complaint.
• Accompanied by fungal skin infection or eczema
• Treatment:
• Selenium sulphide shampoo

6. 6
Enzymes
• Trypsin & chymotrypsin: (proteolytic enzymes)
• In chewing gum & toothpaste to destroy dental plaque
• Varidase: (Streptokinase & streptodornase)
• Breaks down blood clots & dead tissue around wounds
• Helps healing of wounds & surgical incision
• Use carefully in bleeding disorders, or in patients using
NSAIDs, warfarin, or given heparin
• Hyaluronidase:
• It hydrolyzes hyaluronic acid in connective tissues
• Given SC dissolved in saline to facilitates spread of
drug solutions & prevention of adhesions
• Not used with local anesthetics or if there is infection

7. Obtundents
Agents which are used to either diminish or eliminate the
dentine sensitivity to make the excavation painless.
• An ideal obtundent should possess the following
characteristics
– It should remove dentive sensitivity and penetrate the dentine
sufficiently.
– It should not stain the dentine.
– It should be free from any local irritation or pain.
7

8. Obtundents
I. Act by destroying the nervous tissue – Absolute alcohol
II. Act by paralysing the sensory nerve endings
• Phenol creosote
• Benzyl alcohol
• Camphor
• Thymol
• Menthol
• Eugenol (clove oil)
III. Act by precipitating proteins
• Silver nitrate
• Zinc chloride
8

9. 9
Fluorides
• Compounds that release fluoride ion:
Monofluorophosphate, Na fluoride, Stannous fluoride
Actions & uses of Fluorides:
• Strengthen the enamel & prevents dental caries
Prevent decalcification of the structure of tooth by inhibiting
bacterial enzymes which produce lactic acid
Modes of use:
• Topically: In toothpaste or solution for mouth rinses
• Systemically: Via water fluoridation (1 part per million), fluoride
tablets & drops, fluorinated table salt or milk

10. 10
Fluorides
Adv. Effects:
Acute overdose:
•Nausea, vomiting & muscle spasm
Chronic overdose:
•Dental fluorosis: white patches & hypoplasia of teeth
•Increased bone density: in spine, pelvis & long bones

11. 11
Mummifying agents
Agents used to harden & dry tissues of the pulp & root canal
so that the tissues are resistant to infection.
A combination of various mummifying agents are used in
the form of paste or semi-liquid preparation.
PARAFORM paste
–(zinc oxide or zinc sulphate, glycerine & creosote)
IODOFORM paste
–(tannic acid, phenol, eugenol, cinnamon oil & glycerine)
Tannic acid glycerine,

12. Mummifying agents
Paraformaldehyde paste
•These drugs mummify (or fix) coronal and radicular pulp
•Used during “2 stage non-vital pulpotomy technique
•Place paraformaldehyde over exposed pulp, formaldehyde
released fixes pulp, seal cavity with thin layer of ZnO &
eugenol paste
•After 1-2 weeks remove non-vital pulp, give antiseptic
dressing & seal cavity with hard setting cement
12

13. 13
Treatment of common oral diseases
Dental caries : Most common oral condition & dental emergency
• Removal of the softened & infected hard tissues, sealing of exposed
dentines and restoration of the lost tooth structure with porcelain,
silver, amalgam, composite plastic, gold, etc.
Dental hypersensitivity: Exposure of dentine to oral environment
•Toothpastes containing strontium chloride & formaldehyde
Acute puplitis: Inflammation of the pulp as a result of caries
•Apply 1% triamcenolone + 3% demeclocycline paste
•Root canal therapy (RCT) for irreversible pulpitis
Periapical abscess:
• Incision & drainage or RCT or extraction
– With Amoxicillin + Metronidazole+ NSAlDs.

14. Treatment of common oral diseases (Cont.)
Periodontal abscess:
•Drain abscess & irrigate with 0.2% chlorhexidine
Cellulitis & Ludwig’s angina: Usually streptococcal
infection
•Drainage and, if necessary, treachostomy
•Amoxicillin + Metronidazole IV & NSAIDs
Pericoronitis:
Localized pericoronitis:
– hot saline mouthwashes & irrigation under the flap
Severe cases with cellulitis:
– Amoxicillin + Metronidazole IV & NSAIDs
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15. 15
Treatment of common oral diseases (Cont.)
Herpetic labialis: Acyclovir cream 5%
Herpetic gingivo-stomatitis: Acyclovir 200 mg orally &
chlorhexidine 0.2 % mouth wash, both 4-5 times/d
Candidiasis: (oral thrush & angular cheilitis)
•Topical nystatin, amphoterricin B, miconazole
Recurrent aphthous ulcer: Due to sharp edge of tooth
•Treat cause, chlorhexidine & benzydamine mouth wash
Dry socket: Infection of tooth socket after extraction
•Clean with warm saline, dressing with guaze soaked with iodoform,
euginol & butyl-paraminobenzoate