Pigmented deposits on the tooth surface are called dental stains.
Causes: Stains are ordinary colorless. The acquired or developmental coating become pigmented by-
i. Chromogenic bacteria.
There are several types of stains physically as well as chemically. Some of them are describe here.
(a) Brown stain:
# This is a thin, translucent, acquired bacteria free pigment pellicle.
# The color is due to tannin.
# Causes-Insufficient brushing.
- Inadequate cleansing action of dentifrice.
(1) Buccal surface of maxillary molars.
(2) Lingual surface of mandibular incisors.
(b) Tobacco stain:
These are tenacious dark brown or black with brown discoloration. Causes:
(1) Coltar combustion products.
(2) Penetration of pits and fissures, enamel and dentine by tobacco juices.
(c) Black stain:
This is a thin black line, firmly attaches, tends to recur, common in woman, may occur in excellent hygiene.
(1) Near the gingival margin of facial and lingual surface of a tooth.
(2) Diffuse patch on the proximal surface may be seen.
(1) Associated with low incidence of caries in children.
(2) Chromogenic bacteria-e.g.-Gm. positive rods-Actimomyces species -Bacteriods melaninogenicus.
(d) Orange stain:
Both facial and lingual surface of anterior teeth.
Serratia marcescens, Flavobactraium lutescens.
(e) Green stain:
These are green or greenish yellow stains of considerable thickness. This type of stain is considered as stained remnants of enamel cuticles. Children are frequently affected.
(i) Fluorescent bacteria-Penicillium.
(iii) Associated with children with T. B. or cervical lymph node.
Site: Facial surface of maxillary anterior teeth
(f) Metallic stain:
This type of stain is caused by metals and metallic salts. Metals are penetrated into tooth substances and produces permanent decolonization or they bind with pellicle and produce surface stain.
Source of metals:
(I) Introduction of metals into oral cavity.
(II) Metal containing dust inhalation by worker.
(III) Oral administration of drugs.
Some metals that cause’s stains:
Copper dust-Green stain Iron dust-Brown stain Magnesium-Black stain Silver-Black stain Iodine-Black stain Nical-Green stain.
Metal penetrating into tooth substance causes permanent discoloration where as that bind with pellicle causes surface stain.
(g) Chlorhexidine stain:
Chlorhexidine has affinity for sulfate and acidic groups such as those found in pellicle, plaque constituents, carious lesion and bacterial cell wall. So it is retained into oral cavity and stained oral tissues.
(i) Cervical and interproximal area of the teeth
(ii) Plaque and other restorations
(iii) Tongue Color: Yellowish brown to brownish.
Removal: The stains are not permanent in nature.It can be removing with proper brushing with dentifrice.