basic tooth and periodontium :) Flashcards
what is the cervix of the tooth
where the crown joints the root
what is the bottom point of the tooth
apex
what is the clinical crown
crown seen in paitents mouth
what is the anatomical crown
entire crown
gingivae overlines the cervix of the tooth
what is enamel
layer of tissue which covers the anatomical crown of tooth
what is enamel derived from
ectoderm cells
what is enamel when fully formed
non vital acellular so cannot be repaired
what runs through enamel tissue
enamel rods/prisms
how is enamel deposited
increments
what is dentine derived frm
ecomesenchyme
mineralisation of dentine and enamel
dentine 70
enamel 96
is dentine living or non living
living
properties of dentine
compressive and tensile strength
acts as a cushion for enamel
what are found within the dentine
dentine tubules
what do dentine tubles contain
odontoblast cell processes extending from odontoblast cell bodies
where do odontonblasts cell bodies lie
pulp dentine boundary
where is dentine laid down around
around the tubules
what happens to the odontoblasts in the dentine
remain on pulp dentine boundary in quiesent state
can be reactivated to produce new dentine
what is the pulp
centre of the tooth
what is the pulp derived from
ectomesechyme
describe the pulp
soft vital connective tissue
odontoblast cells line the outside of the pulp
occupies pulp chamber in crown and root canals
what covers the tooth root
cementum
what is cementum derived from
ectomesenchyme
mineralisation of cementum
55% mineral
where is acellular cementum
towards the crown of the tooth
where is cellular cementum
towards the apex of teh tooth
what is found in cellular cementum
cementocytes in lacunae
name the periodontal tissues
periodontal ligament
alveolar bone
gingiva
what is PDL derived from
ectomesenchyme
what is the alveolar bone
part of mandible and maxilla which supports the tooth roots and creaes the tooth socket
what does the alveolar bone do
form anchor for PDL fibres
what does alveolar bone respond to
loading
gingivae in health
pale pink
thick
keratinised
adjacent to cervix of tooth
oral mucosa in health
red
lines oral cavity
stretches
found in low abrasion areas
type of epithelium of gingivae
stratified sqamous keratinised
purpose of gingivae
form protective region where teeth pierce epithelium
oral mucosa epithelium
stratified squamous
can be keratinised
dentition types for humans
primary
permanent
how many teeth in primary
20 2 incisors 1 canine 2 molars ABCDE
Permanent dentition
16 teeth
quadrants for permanent/primary
1-4
5-8
what does the PDL do
connects cementum of tooth to the
- alveolar bone
- adjacent teeth
- gingivae
why do fibres go in different directions
supports the root of the tooth within the socket
help bring the tooth back uo after pressure is allied
what reforms during orthodontic treatment
PDL (apart from the end inserted into the cementum as the cementum doesnt remodel)
composition of the PDL
dense fibrous tissue
collagen with formative fibroblasts interspersed, neurovaualr bundles
- arranged in different orientations to absorb masticatory load
types of forces applied to the tooth
axially (down towards the apex)
rotational
tiliting
