ETIOLOGY OF PERIODONTAL DISEASE
PERIODONTAL DISEASE
- Disease of the supporting structures of the teeth
- Usually caused by PLAQUE
- Gingivitisā inļ¬ammation conļ¬ned to the gingiva
- Periodontitis- inļ¬ammatory disease resulting to the destruction of periodontal ligament and
alveolar bone
ARE FETUSES STERILE
- Yes
- Microorganisms are ļ¬rst acquired during birth
- After around 2 years, there are 1.3-10x more bacteria than human cells
COLONIZERS OF INFANT MOUTH
- Colonization of the oral cavity also starts close to the time of birth
- Within hours after birth -> facultative and aerobic bacteria
- Vaginal microbiota or skin microbiota
- Second day -> anaerobic bacteria
1. Streptococcus salivarius and Streptococcus mitis
Streptococcus mitis
- First and most dominant
2. Veillonella spp., Neisseria spp., Actinomyces spp., and Staphylococcus spp.
- Also among the ļ¬rst colonizers of the oral cavity
3. Streptococcus sanguinis, Lactobacillus spp., and Streptococcus oralis
Streptococcus mitis (right)
- After tooth eruption
4. Oral Streptococci - after ļ¬rst year of life
a. S. oralis
b. Streptococcus anginosus
c. Streptococcus mutans
d. Streptococcus sobrinus
e. Streptococcus gordonii
5. Fusobacterium spp., Prevotella spp.
- For young children
Are all oral bacteria bad?
- No
- Most oral bacteria are harmless commensals
- Disease can still occur
- Increased mass and/or pathogenicity
- Suppression of commensal or beneļ¬cial bacteria
- Reduced host response
- e.g. candida infections; s. sanguinis
- Periodontal microbiota both affects and is affected by the host
MICROBES AND ORAL CAVITY
- Bacteria adhere to surfaces
- Soft tissue surfaces are actively involved in the process of bacterial adhesion
- In periodontal pockets, studies have shown high numbers of bacteria attached to pocket
epithelial cells in vivo
- Areas of gingival inļ¬ammation are characterized by an increased number of adhering bacteria
- Bacteria adhere to hard surfaces as well
- Teeth and implants- unique
- Hard and non-shedding
- Ectodermal interruption- protected by junctional epithelium
- Crevicular ļ¬uid aids in protection of periodontal pocket
- Accumulation and metabolism of bacteria on these hard surfaces are primary causes of caries,
gingivitis, periodontitis, peri-implantitis, and, sometimes, bad breath
