development of the dentition Flashcards
growth
1) increase in number and size of cells
- increase body size and weight -
development
1) qualitative (functional abilities)
- advancement of skills needed to function
maturity
1) increase in complexity and ability
2) function at higher level
differentiation
1) early cells and structures modified to achieve a specific function
basic concepts
1) all components are interrelated
2) healthy individuals go through same growth stages
3) diff parts of body grow at diff times and rates
4) grow potential is primarily related to genetics
5) attaining growth potential due to environment
6) motor development is cephalocaudal, and progresses proximodistal
growth assessment indices
1) chronologic age
2) biologic age
- developmental (speech and language)
- skeletal age (hand wrist and cephs)
- dental age
skeletal age
1) hand wrist radiographs
- compare to atlas standards
2) begin with distal ends of radius and ulna => carpals => metacarpals => phalanges
lateral cephs
1) size and shape of C2-C4
2) good correlation with puberty
3) difficult to quantify growth
4) direction and proportion of growth 5)
dental age
1) teeth erupted
2) primary root resorption
3) permanent tooth development
4) compare it to a known chronological age
common growth parameters
1) height
- length or stature
- decreasing rate of growth over time except for pubertal spurt
2) growth proportions
- extremities and trunk grow faster first
- eventually become equal
body weight
1) newborns weight about 7.5 lbs
- initial drop followed by rapid growth
2) head circumference
- massive increase in first year but drops with age
rate of growth
1) infancy
- rapid but declining
2) childhood
- stable, slight decline
3) adolescence
- pubertal growth spurt
4 )adult
- declining to completion
which period has the higher rate of growth
1) infancy
neural
1) brain, spinal cord, optic, and auditory systems
2) 95% adult size at age 7-8
3) rapid early neural brain growth due to fontanelles
lymphoid
1) thymus, adenoids, tonsils, lymphoid tissue,
2) indicator of immune health
3) spikes at 200% of adult size at age 10
4) cervical lymph nodes may be palpable, but should not be tender in a 10 year old
general
1) skeleton, muscular
genital
1) primary and secondary sex characteristics
2) rapid development at puberty
3) if too early, may be a cause for concern
which systemic growth curve matures the slowest
?
maxillary and mandibular
1) lagging development of mandible
2) causes convex facial profile associated with pediatric face
sequence of calcification
1) 14 weeks in utero - 19 weeks
2) central incisors => first molars => lateral incisors =>canines => second molars
3) formation of dentition 6 wks
anomalies in newborn
1) inclusion cysts
- episteins pearlys
- brohns nodules
- dental lamina cyst
* early colonization of cariogenic bacteria
2) natal and neonatal teeth
- predeciduous teeth
- primary teeth erupt prematurely
3) eruption hematoma
inclusion cysts
1) bohnls nodules
- B and L aspects of dental ridges
- remnants of mucous gland
2) epsteins pearl
- mid palatine raphe
- remnants of dental epithelium
sequence of eruption
1) lateral incisors erupt before first molars
- but first molars calcify first
6 mo-24 mo
—
1) 6 wees in utero - primary teeth begin to form
2) 3-4 months - calcification
—
3) 1st - primary teeth enamel complete
4) 2nd year - primary teeth erupted
5 )3rd year - roots of primary teeth complete
primary significance of
1) evaluation of dental development
2) clues to developmental discrepancy (pre and post natal injury)
natal teeth
1) present at birth
neonatal teeth
1) within 30 days after birth
predeciduous teeth
1) supernumerary or not normal
2) extracted for aspiration risk
3) 1/4000
primary but erupted prematurely
1) should not be extracted unless mobile
2) 1/2000
eruption hematoma
1) bluish, opaque
2) bleeding into follicular sac
3) as the tooth erupts, it resolves
anatomy of primary teeth
1) generalized spacing is common
2) lack of spacing may lead to crowding in permanent dentition
3) primate space
- distal of lower canine and medial of upper canine
evaluate primary dentition
1) overjet and overbite
2) overbite is vertical overlap of the teeth
3) overjet is the horizontal distance
4) open bite is not normal occlusion
primary molar relationship
1) flush
- end to end
2) mesial step
- class I
3) distal step
- class II
4) exaggerated mesial step
- class III
primary canine relationship
1) class I
- cusp tip of max canine is same vertical plane as mandibular
2) class II
- mand canine distal to class II
3) class III
- mand canine mesial to class II
exfoliation of primary teeth
1) eruptive pressure of the permanent tooth
2) stimulation of osteoclasts, resorption of dentine, cementum and adjacent bone
3) apex and its surroundings
4) can be hastened by abscess or trauma
5) can be delayed by ankylosis
transition from primary to permanent
1) around age 6
2) mandibular permanent central incisor first
3) girls before boys
4) eruption follows exfoliation by 6 mo
5) enamel complete about 3 years before erupting
6 )root formation completion causes eruption
7) root formation complete 3-4 years after eruption
8) perm first molars are mesially inclined and can cause closure of spaces
9) attrition of primary dentition is common
early mixed dentition
1) 6-9 years
2) mandibular and maxillary 1st molars
3) mandibular and maxillary permanent central incisors and laterals
incisor transition
1) interdental spacing of primary teeth
2) intercanine arch width growth
3) intercanine arch length increase due to anterior placement of permanent incisors
4) parents are quite concerned about this gap
late mixed dentition
1) 9-12 years
2) upper and lower canines
3) premolars
4) second permanent molars
5) if primary dentition is lost prematurely, can lose space (cause crowding usually in last teeth to erupt)
- ex. max canines
- ex man 2nd premolar
leeway space
1) tooth size differential between the primary canines and molars and their permanent successors
- premolars are smaller than primary molars
- so its about 0.9 mm and 1.7 mm of leeway
eruption sequence
know it
