Normal and Abnormal Facial Growth Flashcards
how long does facial growth last?
until late teens to a small extent in adult hood
what 2 ways is bone laid down?
endochondral - within a cartilage
intramembranous - within a memebrane
how does bone remodel?
by laying down or resorption
how do bones connect to each other?
sutures (non movable)
except tmj (movable)
what structures make the face?
calvarium (skull)
cranial base
nasomaxillary complex
mandible
what type of ossification is calvarium?
intramembranous
how many fontanelles are there at birth?
6
when are all fontanelles closed by after birth?
18 months
why do fontanelles not close before birth?
allows compression of head at birth
where does bone formation and bone resorption take place?
bone formation - externally
bone resorption - internally
what type of ossification makes the cranial base?
endochondreal
what makes up the nasomaxillary complex?
maxilla, nasal septum and zygomatic bones
what type of ossification takes place to make the nasomaxillary complex?
intramembranous
what type of ossification takes place to form the mandible?
endochondreal
in females when is facial growth finished?
16 - 17 yrs
in males when is facial growth finished?
17-19 yrs
what stage in life can the mandible have late growth?
early 20s
why do teeth lie in a position of equilibrium?
due to forces being applied from lips, tongue, cheeks
when does the first tooth in the deciduous dentition erupt?
6 mths
when is the deciduous dentition usually complete?
age 3
when is root formation in deciduous dentition complete?
18 mths post eruption
when does calcification of the primary teeth happen?
in utero
when do deciduous teeth start to exfoliate?
6 yrs
when is root formation complete in the permanent dentition?
3 yrs after eruption
when is the permanent dentition usually complete?
13 yrs old apart from the 8s
why are anterior permanent teeth bigger?
they erupt into a bigger arch
there was spacing in the deciduous dentition
growth of the jaw
what is the leeway space?
difference between the sum of the mesiodistal crown widths of the primary canines and molars and that of their successors, the permanent canines and premolars
at what age is late crowding in the lower incisors found?
late teens/early 20s - due to late growth of the mandible and general mesial migration of teeth
what is craniosynotosis?
premature fusing of stures on calvarium - creates abnormal shaped head
what is an example of an abnormality in growth of nasomaxillary complex and oral musculature?
cleft lip and palate
what is the LAHSHAL system?
describes site, size, extent and type of cleft
L - lip
A - alveolus
H - hard palate
S - soft palate
H
A
L
when is cleft palate/lip often diagnosed?
ultrasound around 20 wks of pregnancy
what are the dental problems with cleft?
hypodontia
supernumerary teeth
ectopic teeth
hypoplastic teeth
malformed teeth
high caries rate
natal teeth
what is the management and prevention for cleft
regular check ups
OHI
diet advice
fluoride application - duraphat varnish, mouthwash, toothpaste (duraphat)
alveolar bone grafting
definitive orthodontics and alignment
distraction osteogensis
what is the purpose of alveolar bone grafting?
facilitates eruption of the teeth and support teeth on either side of cleft site
improves aesthetics
