Class 1 Flashcards
Adolescence
Period between juvenile and adulthood
Fertility is attained
Sex hormones ____ lymphoid tissue
Shrinks
Endochondral growth and sex hormones
Stimulate cartilage growth
And an even greater increase in transformation of cartilage to bone
Female growth spurt
1.5 to 2 years earlier in females than males
Female growth spurt begins around
10
Ends 3 years later
Male growth spurt begins
Begins 12.5
Ends up to 5 years later
Male grows bigger because
Slower to start and longer
Chronologic age is
No indication of where an individual is developmentally
Growth height correlates with
Jaw growth
Females growth spurt ends with
Menarche
Cervical Verterbeal Maturation Stage
vertebra become more rectangular
Serial Radiographs
Superimposition to monitor growth
Mandibular growth reflects….
General growth curve
Maxillary growth most resembles
Neural growth curve
Facial growth is _____growth
Differential
Differential jaw growth
Mandible goes more and longer
Mandible more prominent
Profile becomes less convex
Width stops before ______ before ______
Length
Height
Width stops before
Growth spurt except alveolar arches widen in the area of molar eruption
Length and height increase through
Puberty
Height of face grows longer than
Length dues to vertical growth of mandible
Leeway space
Difference in mesial distal width between primary canines/molars and permanent canine/premolars
Permanent molars move
Into leeway space
If anterior crowding is present send to orthodontist before
Primary 2nd molars exfoliate
E-space
Difference in mesial distal width between primary 2nd molars and permanent 2nd premolars
Primary molar occlusion
Mesial step
Flush
Distal step
Mesial step usually becomes
Class I
Flush terminal and still step usually become
Class II
Late Mesial shift
Mandibular molars greater movement
Prevalence of Class II _____ with age
Decreases
Permanent incisors lie _____ to primary incisors
Lingual
Permanent incisors are _______ wider than primary
2-3.5 mm
Eruption of lateral incisors force mandibular canines
distally into primate space
Permanent maxillary incisors erupt
Labial
Developmental spaces
Spaces between incisors
Primate spaces
Spaces between canines
Mesial of maxillary canine
Distal of mandibular canine
Canine erupt
Buccally
Incisor replacement 4 things
Spacing
Labial eruption
Increase in arch
Distal repositioning
Central diastema closes with
Eruption of lateral incisors
If not will close with canines
The mandible grows
Downward and forward
The mandible ______ and ______ via _____ and ____
Grows and envelopes translation and remodeling
Three dimensional Imaging
CAT Scans
Cone Beam CT
MRI
Interestitial
Insides the tissues
Growth that occurs by a combination of hyperplasia hypertorphy and secretion of ECM
Interstitial growth occurs at
All points within the tissue
Cranial base is a form of ___growth
Interstitial
Hyperplasia
Proliferation cells
Hypertorphy
Increase in cell siE
If ECM is not mineralized
Interstitial growth may continue in soft tissues and cartilages
Appositional Growth
Growth that occurs by a combination of hyperplasia hypertorphy and secretion of ECM
Occurs ONLY at the surface of bones
Appositional growth occurs though activity of
Cells in the periosteum
Cranial vault, maxilla, and mandible examples of ____growth
Appositional
______ can grow interstitially but _____ cant
Cartilage
Bone
Once cartilage is transformed into bone it cones to grow but only by
apposition
Endochondral bone
Bone within cartilage
Ossification centers within cartilage
Chondrocranium
Ethmoid
Sphenoid
Basioociptal bones
Chondocranium and epiphyseal plate _______ growth
Endochondral ossification
Intramembranous
Secretion of bone matrix within and between connective tissue
______ no intermediate formation of cartilage or replacement of cartilage
Intramembranous
Desmocranium
Cranial vault maxilla and mandible
Desmocranium _____ ossification
Intramembranous
The mandible forms by intramembranous bone formation just lateral to ______
Meckels cartilage
Remanent of meckels cartilage
Sphenomandibular ligament
Condylar cartilage
Does not form from meckels cartilage
Develops from independent secondary cartilage fuses with mandibular Ramus
Surface Modeling
Change in shape of bones
The result of bone in one area and bone addition in another
_____ occurs at the surface of growing endochondral and intramembranous bones
Surface modeling
Internal Remdoleing
Vascular channels within bones bring osteocytes to the area
Allows the bone to adapt to mechanical stress
_________ does not age bone grow or change shape
Internal remodeling
Internal remodeling allows
Exchange of calcium and phosphate
Adapt to mechanical stress
Cranial Vault
Flat bone formed from intramembranous formation a from ossification centers
No cartilaginous precursors
Predictable activity results in bone modeling both at sutures and at inner and outer surfaces
2 types of growth at cranial vault
Intramembranous
Bone remodeling
Cranial sutures and Fontanelles lined by
Periosteum
Bones of the base of the skull formed by
Endochondral ossification
Synchondroses of the cranial base
Cartilaginous joints between the bones of the cranial base
Immovable joints
Most important synchondrosis
Spheno-ethmoidal, inter-sphenoidal, spheno-occipital
_____ growth occurs within synchondroses
Endochondral
Growth at synchondroses ______ the area of the ______
Lengthens
Cranial base
Suture
Junction between adjacent bone
Connective tissue**
Appositional ossification
The nasomaxillary complex is formed by____ and growth is done by
Intramembranous ossification with no cartilaginous precursors
Appositional and surface modeling
Translation of maxilla
Downward and forward until 6-7
Translation of maxilla is due to
Growth of nasal cartilage
Maxilla surface remodeling occurs
Anterior is resorbed
Appositional of bone occurs at the maxillary tuberosity
The palate moves _______ and widens _______ because bone is resorbed in the floor of the_____ and apposition occurs at ____
Downward
Widens transversely
Nose
Palate alveolar process
What part of the mandible grows by endochondral growth
The condyle
Body of the mandible grows
Longer
Ramus of the mandible grows
Higher
Site of growths
A location at which growth occurs
Center of growth
A location at which independent growth occurs
All centers of growth are also
Growth sites but the reverse is not true
Suture theory
All tissues that form bone have intrinsic potential to do so
Growth centers are locations of genetically controlled growth independent from environment
INclused sutures periosteum synchondroses and mandibular condyles
Suture theory evidence
Does NOT support this theory
Sutures and periosteum ARE _______
Sutures ____ rather than acting independently
Growth sites
React
Cartilage theory
All cartilage are growth centers
Cartilage theory evidence
PARTLY supports this theory
Transplanter cartilage from synchondroses and nasal septum is capable of growth
Transplanted cartilage from mandibular condyles shows significantly less growth
Synchondroses and nasal septum act as growth centers but condyles don’t
Functional Matrix theory
Heredity and genes play NO role in growth of craniofacial skeleton
Growth of the face occurs in response to functional needs mediated by soft tissues in which the bones are embedded
All tissues that form bone are merely growth sites
Functional Matrix theory: Mandibular Ankylosis
Occurs as a result of infection or trauma in TMJ area
Mechanical restriction due to scarring prevents growth of mandible
Functional Matrix Theory: clinical application
Rapid maxillary expansions
Distraction osteogenesis
Function matrix theory Evidence
Partial veracity
It is not clear how functional needs are transmitted
Genes have been shown to be involved
Growth of cranium is a response to
Growth of brain
Sutures +periosteum = growth sites
Growth of cranial base is a result of
Of endochonral growth at synchondroses
Growth centers
Growth of the maxilla is primarily a result of
Apposition and model oaks the bone is translated by soft tissues
Sutures + periosteum = growth sites
Growth of maxilla may result from endochondral growth at
Nasal septum cartilage
Growth of the mandible occurs by
Endochondral growth at condyle and surface modeling as the bone is translated by soft tissues
Condyle + periosteum = growth sites