An astringent substance is a chemical that tends to shrink or constrict body tissues, usually locally after topical medicinal application. Astringent medicines cause shrinkage of mucous membranes or exposed tissues and are often used internally to check discharge of blood serum or mucous secretions. Externally applied astringents causes mild coagulation of skin proteins, dry, harden and protect the skin.
Displacement of the gingiva is necessary to allow filling of the pocket and with a maximum amount of cord and it is desirably done as gently and with as little discomfort to the patient as possible. Gingival cord is used by dentists for introducing drugs into the pocket between a tooth and the adjacent gingiva.
For both intraoral and dermatological applications, present astringent materials for application to body tissues are comprised of active ingredients which immediately react with the body tissues upon contact therewith. If a practitioner applies an excessively large quantity of such material to the tissues, then those tissues are immediately subjected to an excessively large quantity of reactive agent. A problem that may result from such an occurrence is that delicate tissues may be irritated by the excess astringent substances. Thus, it is an object of the invention to provide an astringent composition which provides an active astringent on demand for contact with body tissues and therefore does not subject the delicate tissues to excessive quantities of reactive agents which cause tissue irritation.
Astringents cause contraction of tissues.They accomplish this by constricting small blood vessels, extracting water from tissue or precipitating protein. Dentist can apply astringents to gingival tissues before taking impressions, placing Class V or root surface restorations. They can alone be used in combination with retraction cords.
Aluminium Chloride causes contraction or shrinking of tissues, making it useful in retracting gingival tissue. It also reduces secretions and minor hemorrhage. Ferric Sulphate is an effective and safe astringent and heamoststic for use in gingival retraction. Aluminium sulphate with other aluminium salts is an effective and safe astringent and haemostatic for use in gingival retraction. Aluminium Potassium Sulphate is not widely used, due to its limited properties.
|Name||Form/strength||Dosage||Precautions/ Contraindications||Adverse effects|
|Aluminim chloride||Gel and solution = 20%; Oint= 25%; Retraction chord= 3.5mg/in||Adults: Apply product directly to tissues using a cotton pledget or apply to gingival retraction cord||not significant to dentistry||Concentrated aluminium chloride is acidic and may even have an irritating and even caustic effect on tissues|
|Aluminim potassium sulphate||Pow= 100%various concentration available||Adults: Any concentration, including 100% powder can be used||not significant to dentistry||may have an irritating effect|
|Aluminim sulphate||Cotton pellet: 2.20- 2.80mg/pellet; Gel in unit dose cartridge; Impregnated retraction chord; topical soln.||Adults: Apply product directly to tissues using a cotton pledget or apply to gingival retraction cord||not significant to dentistry||may have an irritating and even caustic effect on tissues|
|Ferric chloride||NA||Adults: Apply product directly to tissues using a cotton pledget or apply to gingival retraction cord||NA||NA|
|Ferric sub sulphate||NA||NA||NA|
|Ferric Sulphate||Solution||not significant to dentistry||Compound may cause tissue injury more than the aluminium compounds|
|Ferric sulphate/ Ferric sub sulphate||Sol= 25%||NA||NA|
|Name||Dosage||Precautions/ Contraindications||Adverse effects|
|Retraction cord, plain||Use as directed||--||--|
|Retraction cord with aluminium chloride||Use as directed||History of allergy||May cause irritation or tissue destruction|
|Retraction paste, plain||Use as directed||--|
|Retraction paste with aluminium chloride (6.5%  aluminium chloride)||Use as directed||History of allergy||May cause irritation or tissue destruction|
|Retraction cord with aluminium sulphate||Use as directed||--||May cause irritation or may even have caustic effect.|
|Retraction cord with aluminium potassium sulphate||Use as directed||--||May cause irritation|
|Retraction cord with epinephrine (0.5mg/in)||Use as directed||W/P: Patient's medical history and oral health, type of procedure to be done, amount and length of retraction and exposure of the vascular bed should be considered before epinephrine use. Contraindication: Patients with history of CV disease. Diabetes, hyperthyroidism, hypertension and arteriosclerosis||May cause irritation and tissue destruction|