inner enamel epithelium and outer enamel epithelium squished together (no stellate rticulum or stratum intermedium)
once the cervical loop extends deeper into the ectomesenchyme what does it become?
hertwing's epithelial root sheath (HERS)
how is dentin formed along the root?
HERS induces dental papilla to differentiate into odontoblasts
Odontoblasts leave the dentin matrix
HERS disintegrates
what are epithelial rests of Malassez
HERS that didn't disintegrate and get lost, they can become cystic and cause problems
What can't enamel form in the root?
without the stratum intermedium and stellate reticulum the ameloblasts cannot form
what induces cells of the dental sac to become cementoblasts?
dentin
what is the only slimy trail (matrix) to have a name?
cementoblasts matrix-cementoid
what are the cementoblasts cell bodies called and where do they leave it?
cementocytes
within the matrix
through _____ the dental papilla now forms into the ___ of the tooth.
induction
pulp
the ectomesenchyme from the dental sac ____ into the _____ ____ adjacent to the cementum
differentiates
periodontal ligament
the ectomesenchyme from the___ ___ differentiates into the ____ ___ surrounding each tooth.
dental sac
alveolar bone
what does the periodontal ligament anchor into?
cementum and alveolar bone
how are multirooted teeth formed?
cervical loop splits into multiple roots
what are the developmental disturbances during root formation?
enamel pearls
concrescence
dilaceration
accessory roots
what is it when the ameloblasts get lost and start forming enamel in abnormal places?
enamel pearls
what is it called when two teeth get stuck together by cementum?
concrescence
what is it called when because of injury or pressure the HERS get distorted and make the roots bend?
dilaceration
what is an accessory root?
extra roots because of injury pressure or metabloic disease of HERS
what kind of eruption is actual vertical movement of the tooth?
active eruption
what kind of eruption is it when gingiva recedes around tooth?
passive eruption
what is reduced enamel epithelium and what does it do?
enamel organ squished together
REE fuses with the oral epithelium and disintegrates it to make a tunnel for eruption
what two kinds of cells are needed for primary tooth shedding?
osteoclasts
odontoclasts
what cell dissolves the bone around the tooth in primary tooth shedding?
osetoclasts
what cell dissolves the roots of the tooth in primary tooth shedding?
odontoclasts
What happens when the primary tooth is not quite ready to come out?
osteoblasts, odontoblasts and cementoblasts replace the reabsorbed bone and root. That is why kids teeth will feel really loose and then suddenly tighten up again
what is the nasmyth's membrane?
left over REE and oral epithelium that sticks to the newly erupted teeth and catches stain
how do you remove the nasmyth's membrane?
polishes off
all succedaneous teeth form and erupt _____ to the primary teeth except the maxillary incisors that erupt _____ to the primary teeth.
Lingually
Facially
what are the two types of developmental disturbances during eruption?
dentigerous cyst
eruption cyst
what is a dentigerous cyst?
the REE forms a cyst around the completely formed crown. it can displace teeth and cause pain and must be removed surgically
what is an eruption cyst?
a dentigerous cyst formed around the developing crown. when the tooth erupts it will go away
What developmental disturbance during eruption is around a completely formed crown?
dentigerous cyst
what developmental disturbance during eruption is around a developing crown?
eruption cyst
true/false. a dentigerous cyst will go away on its own when it erupts?
false, a dentigerous cyst must be removed surgically
true/false. a eruption cyst must be removed surgically.
false a eruption cyst will go away on its own when the tooth erupts