Flashcards in Lecture 3 Deck (39):
When is extraction of an ankylosed primary tooth recommended?
-If the primary tooth drops below the height of contour
T/F Growth is controlled both by genetic factors and environmental factors
What is the theory of genetic blue print model?
-The role of genetic preprogramming has long been presumed by many to have a fundamental influence in establishing basic facial pattern
How do bioelectric signals occur?
-From distortions of the crystals in the bone that can lead to the triggering of osteoblastic and osteoclastic responses
What is Wolffs law?
-Bone in a healthy person or animal will adapt to the loads under which it is placed, if loading on a particular bone increases, the bone will remodel itself over time to become stronger
What is the mechanostat theory?
-Bone growth and loss is stimulated by the local mechanical elastic deformation of bone
There is a linear relationship in a healthy body for the growth of bone between what?
-Muscle cross sectional area and bone cross sectional area
What is a growth site?
-A location at which growth occurs
What is a growth center?
-Location at which independent growth occurs regardless of the growth and development of adjacent structures
T/F The pressure created by growth at the sutures, causes the maxilla to be pushed downward and forward
-People used to think this was true but later discovered it was not true
If a piece of epiphyseal plate is transplanted somewhere else and it keeps growing does that make it a growth site or growth center?
Are sutures growth sites or growth centers?
Synchondroses are growth centers or growth sites?
Is the nasal septum a growth site or growth center?
What does growth typically refer to?
-increase in size, but it can tend to be more linked to change than anything else
T/F All of the tissue systems of the body grow at the same rate
-They do not grow at the same rate
What does a change in growth pattern indicate?
-Some alteration in the expected changes in body proportions
When is the peak growth for girls?
When is the peak growth for boys?
T/F Boys will generally start growth sooner for a shorter amount of time?
What are the three cellular possibilities for growth?
-Cells secrete extracellular material
T/F Cartilage behaves like soft tissue
THe direct addition of new bone to the bones surface can and does occur through the activity of cells located where?
T/F Bone is formed as a primary tissue
-It is never formed as a primary tissue
T/F Once bone is mineralized interstitial growth is impossible
The greatest period of cranial growth occurs between what age?
-Birth and 5 yrs
What serves as a major site of bone expansion during postnatal craniofacial growth?
For sutures to function as growth sites they need to remain in what state?
-An unossified state
What type of bones is the cranial vault made up of?
-Flat bones formed via intramembranous bone formation
What is the most complex structure of the human skeleton?
What is the first region of the skull to reach adult size?
How does the cranial base form?
What are the three pairs of cartilaginous precursors for the chondrocranium?
Histologically what do synchondroses look like?
-Two-sided epiphyseal plate
T/F Typically more bone deposition occurs on the ethmoid bone at the sphenoethmoidal synchondrosis
How does growth of the maxilla occur?
-Apposition of bone at the sutures by they periosteum
What direction does the maxilla grow?
-Downward and forward
What two ways accomplish the downward and forward growth of the maxilla?
-A push from behind created by cranial base growth
-By compensatory growth at the sutures in response to the displacement of the maxilla through soft tissue growth