Module N1 Soft and Hard deposits

tenacious membranous layer that is amorphous, acellular, and organic

exposed tooth surfaces, as well as over restorations and dental calculus

• 100 to 1000 nm
• gingival margin

• minutes
• salivary glycoproteins from saliva that are selectively adsorbed by the hydroxyapatite of the tooth surface

• Supragingival pellicle
• Subgingival pellicle

Clear, translucent, insoluble and not readily visible until a disclosing agent has been applied

• subsurface pellicle
• tooth structure
• partially demineralized

• Protective-keeps acid away from tooth surface
• Lubrication-keeps teeth moist 
• Nidus for bacteria-pellicle is a part of plaque formation
• Can be an attachment for calculus

• Biofilm growth and maturation
• -The increase in the mass and thickness of biofilm results from bacterial multiplication
• Matrix formation
• -The intermicrobial substance (matrix) is derived mainly from saliva for supragingival biofilm
• From gingival sulcus fluid and exudate for subgingival biofilm

• Day 1 and 2
• Day 2-4
• Day 4-7
• Day 7-14
• Day 14-21

Early biofilm consists primarily of Gram-positive cocci. Streptococci, which dominate the bacterial population, include Streptococcus mutans and Streptococcus sanguis.

• The cocci still dominate, and increase in number. Gram-positive filamentous forms and slender rods may be seen on the surface of the cocci colonies
• Gradually, the filamentous forms grow into the cocci layer and replace many of the cocci.

• Filaments increase in numbers, and a more mixed flora begins to appear with rods, filamentous forms, and fusobacteria
• Biofilm near the gingival margin thickens and develops a more mature flora, with Gram-negative spirochetes and vibrios

• –Vibrios and spirochetes appear, and the number of white blood cells increases. As biofilm matures and thickens, more Gram-negative and anaerobic organisms appear.
• During this period, signs of inflammation are beginning to be observed in the gingiva

• Vibrios and spirochetes are prevalent in older biofilm, along with cocci and filamentous forms
• Gingivitis is evident clinically

• Inorganic elements
• Calcium and phosphorus. The concentration of calcium, phosphorus, and magnesium is higher in biofilm than in saliva
• Organic components
• consists primarily of carbohydrates, proteins, and small amounts of lipids

2 to 3 weeks

• reversible
• a few days

• 1.Role in initiation of dental diseases
• –Caries
• –Periodontal infections
• 2.Formation of dental calculus
• Calculus is essentially mineralized dental biofilm
• 3.General oral cleanliness factor
• The accumulation of dental biofilm on the teeth and tongue contributes to an unpleasant personal esthetic appearance as well as to halitosis

• Material alba
• Food debris

• A loosely connected soft deposit that is clearly visible and is deposited over plaque
• Often seen with food debris and can be easily removed
• Contains living and dead bacteria

• cervical 1/3 and interproximally
• contributes to caries, attracts bacteria
• Some may be removed by rinsing

• Hard deposit, tightly attached mineralized plaque
• Supra is less mineralized than sub. Air makes it chalky, can be dark or creamy white, forms on teeth, dentures, appliances
• Seen more commonly around salivary ducts

• on the clinical crown coronal to the margin of the gingiva, implants, partials and dentures
• On the lingual surfaces of mandibular anterior teeth and the facial surfaces of maxillary first and second molars, opposite the openings of the ducts of the salivary glands
• On the crowns of teeth out of occlusion; nonfunctioning teeth; or teeth that are neglected during daily biofilm removal (toothbrushing, flossing, or other personal care)

• Sub is harder (more dense) than supra
• -brown, black or greenish in color
• Dark from blood pigmentation
• –below the gingival margin

chalky, creamy white, gray yellow

light to dark brown, dark green or black

• 10 to 12 days
• 24 to 72 hours

incremental lines

• partly calcified
• soft dental biofilm

• Acquired pellicle
• Irregularities in tooth surface
• Direct contact

• Interlocking of inorganic crystals of the tooth with the mineralizing dental biofilm
• Most difficult to remove

• Associated with some but not all periodontal disease
• Occurs after the pocket is formed. It doesn’t cause the pocket, plaque does
• Rough surface allows more plaque to adhere
• Reservoir for plaque toxins
• Can’t be removed by brushing and flossing
• May be present sub without redness or swelling although this is not very common

• removal of biofilm by brushing and flossing
• The patient needs to understand the necessity of daily biofilm removal
• Professional maintenance appointments on a regular basis