CE: The Host Flashcards
what is the host?
tooth structure, saliva surrounding tooth, and immune response of saliva/plasma
Caries don’t develop w/o presence of
host
Tooth has 4 major tissues which are?
enamel, dentin, dental pulp, cementum
Enamel
Most mineralized tissue of the body, very hard, thin, translucent layer of calcified tissue that covers the entire anatomic crown of the tooth, vary in thickness and hardness and color
What does the enamel consist of?
No n. or blood supply w/n
Hardness allows teeth to w/stand blunt/heavy masticatory forces
- 95-98% of its Ca & P make up strong hydroxyapatite crystals
- 1-2% of enamelin proteins that have high affinity for binding hydroxyapatite crystals
- 4% water
Rod
Carbonated hydroxyapatite crystals arranged in long thin structures – extend @ right angles from dento-enamel junction
What is surrounding each rod?
Area btw the rods?
protein matrix of enamelin interrod enamel (interrod cement)
Pores
Minute spaces where crystals don’t form btw rods, contribute to enamel’s permeability
if pH drops below 5.5 what happens?
demineralization & crystalline structure shrinks in size while pores enlarge
Ameloblasts do what to enamel?
Enamel gets broken down removing enamels ability to regenerate/repair itself – cannot be restored beyond normal course of remineralization
The tooth at eruption is
Not fully mineralized, complete mineralization with Ca & P & Fluoride ions from saliva by adding a layer of enamel
Genetic disorder: Amelogenesis imperfecta is?
Enamel is never completely mineralized & flakes off exposing softer dentin to cariogenic bacteria. Other conditions linked like GERD and Celiac disease
Dentin Structure
dentin is hard, light yellow, porous layer of tissue under enamel & cementum – is largest portion of the tooth
What is Dentin made of
Ca & P ions form hydroxyapatite crystals that are 30x smaller & softer than enamel
Dentin is a
Living tissue and can repair/regrow – tiny dentinal tubules running btw cementoenamel junction & pulp layer assist in regeneration
What is in the dentin to remineralize it and to feel pain?
Cell processes in pulp layer extend into tubules creating new dentin & mineralizing it, n. pass through these dentinal tubules allowing dentin to transmit pain (unlike enamel)
Pulp Chamber
Soft tissue, containing – coronal pulp w/n crown continuous w/ radicular pulp w/n root
- Pulp contains odontoblasts (creation of dentin) – contains neurons, vascular tissues, fibroblasts, and macrophages BUT doesn’t contain true lymphatic vessels
- Apical foramen @ end of radicular pulp
Cementum
thin, light yellow layer of bone-like tissue covering root of teeth – anchor
teeth to bony walls of the tooth’s socket in periodontium by attaching to periodontal ligament
What is the Cementum made of? and where is it?
Mainly Ca salts, joins enamel @ cervix of tooth @ cementoenamel junction in a sharp line (cementum overlaps enamel for a short distance)
Saliva
Mixture of mucous & serious fluid, bodily fluids that are pale yellow, transparent, and benign in nature, secreted from salivary glands
Parotid gland
largest pair of glands, parotid facial space, posterior to mandibular ramus, anterior & inferior to ear – secretes saliva through Stensen’s ducts to facilitate
mastication & swallowing
Submandibular glands
pair of glands located beneath lower jaws – smaller than parotid,
they produce 70% of saliva via Wharton’s ducts
Both parotid & submandibular glands secrete true saliva
(combo of serious fluid & mucous) also have acini connected to intercalated ducts that connect to striated ducts that have capacity to modify the mineral content of saliva
Sublingual glands
located beneath tongue – secrete mainly mucous & does NOT have striated ducts, releasing mucous directly from acini via excretory ducts
