2. ETIOLOGY OF PERIODONTAL DISEASE
• The clinical manifestations of periodontal
disease result form a complex interplay
between bacteria found in dental plaque and
the host tissues.
• Etiological factors in periodontal disease are
classified into two broad categories,
depending on their specific origin.
3. Primary
Local Factors (dental plaque
Secondary
(plaque retention factors)
Systemic factors
(modify the response of the gingiva to local factor)
4. Dental
plaque
Calculus Tobacco Use
Iatrogenic Local factors Orthodontic
Factors Therapy
Design of
Removable
Partial Restorative Malocclusion
Dentures Dentistry
Procedures
6. Dental Plaque
Dental plaque can be defined as the soft deposits
that form the biofilom adhering to the tooth
surface or other hard surfaces in the oral cavity,
including removable and fixed restorations.
8. • The different regions of plaque are significant
to different processes associated with diseases
of the teeth and periodontum.
9. Plaque Composition
1_Microorganisms which exits within an
intercellular matrix.
Gram positive: S. sanguis, A. viscousus.
(initial colonizers)
Gram negative: P. intermedia,
F.nucleatum.
(secondary colonizers)
10. Plaque Composition
2_The intercellular matrix consists of :
• Organic constituents of the matrix include
polysaccharides, proteins, glycoproteins and lipid
material.
• Inorganic component of plaque is predominately
calcium and phosphorus and other minerals such
as sodium, potassium and fluoride
11. Clinical fissure
• White, greyish or yellow in colour.
• Globular appearance.
• ON gingival third of the tooth surface.
12. Plaque Formation
• Dental pellicle.
• Initial colonization( G. positive)
• The plaque mass matures (colonization and
growth of additional species)
• G .negative anaerobic.
• Dental plaque may be visualized on teeth after 1
or 2 days without oral hygiene measures.
13. Association between plaque
microorganisms and Periodontal
Diseases.
a. Nonspecific plaque hypothesis : that
periodontal disease results from the elaboration
of noxious products by the entire plaque flora.
b. Specific Plaque Hypothesis: that only
certain plaque is pathogenic and its pathogenicity
depends on the presence or increase in specific
microorganisms.
14. 1. Calculus
Consist of mineralized bacterial plaque that forms on
the surfaces of natural teeth and dental prostheses.
16. Supra gingival calculus mostly formed in the
buccal surfaces of the maxillary molars and the
lingual surfaces of the mandibular anterior teeth.
When the gingival tissues recede, sub gingival
calculus becomes exposed.
17. Formation of calculus
Between the first and 14th days of plaque
formation(4 to 8 hours).
Saliva supra gingival calculus
G. Fluid sub gingival calculus.
Calcification begins along the inner surface of
the plaque.
18. There are a positive correlation between the
presence of calculus and the prevalence
of gingivitis but this correlation is not as
important as that between plaque and
gingivitis.
19. 2. Dental Stains
• Dental stains may lead to tissue irritation by
creating a rough tooth surface, which
contributes to plaque accumulation and
retention.
20. 3. Iatrogenic Factors
Deficiencies in the quality of dental
restorations or prostheses are contributing
factors for gingival inflammation and
periodontal destruction.
22. Iatrogenic Factors
b. Over contoured crown :
Over contoured crowns and restorations
tend to accumulate plaque possibly prevent
the self- cleaning mechanisms of the adjacent
cheek, lips and tongue.
23. Iatrogenic Factors
c. Open Contacts:
• Food particles create a favourable
environment for plaque accumulation.
• Acts as a direct mechanical irritant to the
tissue.
29. 9. Tobacco use
the smokers had more sites with:
Deep pockets
Greater attachment loss and
severe periodontal disease.
30. Effects of tobacco use:
• Diminish host response and increase disease
susceptibility.
• Less numbers of T- lymphocytes and less antibody
production and serum levels of IgG.
• Reduce serum IgG antibobies to P. intermedia and F.
nucleatum.
• Diminish neutrophils chemotaxis, phagocytosis or
both.
• Nicotina decrease gingival blood flow.
31. Bibliography
Carranza´s. Clinical Periodontology. 9th ed.
2003. pg:15-55.
Gururaja R. Textbook of Periodontology.
2nd ed. pg: 6.
Klaus H. Color Atlas of Dental Medicine.
Periodontology. Vol 1. 1989. pg: 1- 10.