Local Factors Flashcards
Friskopp 1980
calculus does not directly causes periodontal disease, but it protects and host bacteria, obstructing adequate oral hygiene
Allen 1965
sterile calculus may be encapsulated in connective tissue without causing abscess formation or even marked inflammation
Steralized calculus put in flaps of guinnie pigs
Will all plaque turn in to calculus? Why or why not?
Not all plaque will become calcified, it depends on the binding of calcium ions to carbohydrate protein complexes of the organic matrix and precipitation of crystalline calcium phosphate salts. (Jepsen 2011)
How many “types” of calculus are there? What are they?
According to Jepsen 2011: 2 types - Supragingival and Subgingival
Describe Supragingival Calculus
(Jepsen 2011)
6 characteristics
Color - White/yellow
Position - Coronal to gingival margin
Location - Usually near salivary ducts - facial surface of molars
Mineral Content - 37% - saliva is major contributor
Crystal type - Octacalciumphosphate (external) Hydroxyapatite (Internal)
Formation - Heterotypic nucleation/growth/and calcification
Describe Subgingival Calculus
(Jepsen 2011)
6 characteristics
Color - Brown/Green
Position - Apical to gingival margin from CEJ to pocket base
Location - variable - lingual/interproximals
Mineral content - 58% - GCF major contributor
Crystal type - whitelockite (WHT)
Formation - Heterotopic nucleation/growth - Homogenous calcification
How is calculus attached to the tooth?
According to Zander 1953 there are 4 modes of attachment
RISP
Resorption
Irregularities
Secondary Cuticle
Penetration
1 - secondary cuticle
2 - microscopic irregularities
3 - areas of resorption
4 - microbial penetration
Describe Secondary Cuticle attachment of calculus
There can be a thin cuticle of epithelial attachment that remains attached to cementum after apical migration - calculus can form on this and be easily detached
Describe Microscopic Irregularities attachment of calculus
Adhered by irregularities left from detached Sharpey’s Fibers (MOST COMMON FORM OF ATTACHMENT)
Describe calculus attachment by areas of resorption
Areas where the cementum has resorbed create potential areas of mechanical attachment
Describe calculus attachment by microbial penetration
DESPUTED BY Canis et al 1979
Microbes present on calculus penetrate cementum and lay calculus
What are some tooth related factors that impact periodontal health?
Accessory/lateral canals
Root proximity
Root concavities
Root trunk
Bifurcation ridges
Furcation entrance
Cemental tears
Verticle root fractures
Cervical enamel projections
Enamel pearls
Palatoradicular grooves
Crowding
Helpless teeth
Impacted third molars
How do lateral canals form?
According to Gutman 1978
believed to form by a failure of the HERS where odontoblasts do not differentiate and fail to form dentin
How can lateral canals impact periodontal health and vic versa?
According to Armitage 1999
Canals exposed to periodontal disease can cause “idopathic pulpitis”
Infected canals exposed to periodontium can lead to accelerated periodontal disease progression by spreading endodontic pathogens
What is the prevalence of lateral canals?
According to Gutmann 1978
Average 28.4% in the furcations
Mandibular > Maxillary
(prevalence of about 25-30%)
What is a bifurcation ridge?
A dentin ridge that is covered by a layer of cementum extending from buccal to lingual furca in mandibular molars
What is the prevalence of bifurcation ridges?
Everett 1958 (Mt. Everest) REMEMBER EVERETT
1st Molar - 73%
Hou and Tsai 1997
1st Molar - 73%
2nd Molar - 67.9%
What is a cemental tear?
a root SURFACE fracture that usually involves only cementum, but can involve dentin in rare cases. - commonly associated with periodontal abscess
What are the predisposing factors for a cemental tear?
Lin 2011
Collected from multicenters
Male Gender (3:1)
Age >60
Pocket >6mm
Vital teeth
Position - Incisors (Max and Mand)
Mod-Sev attrition (TFO)
What is a cervico enamel projection?
anatomical anomaly in which there is projection of the enamel tissue on the cervical area of the tooth, pass the CEJ level, extending towards or even into the furcation area.