Chapter 5 Flashcards
What is a normal SNA angle?
82
What type of growth is characteristic of membranous bones?
a) Appositional growth
b) Interstitial growth
a) Appositional growth
T/F: Disorders of ossification: intramembranous (cleidocranial dysplasia, apert’s, crouzon’s). Endochondral bone formation (achondroplasia - depressed midface) Both: Osteogenesis imperfecta
True
What results when the median nasal and maxillary processes fail to fuse?
Cleft lip. prevalence is half that of cleft palate. more often on the left side of the face
What are two syndromes associated with premature closure of cranial sutures?
Apert’s and Crouzon’s (intramembranous)
Which is characterized by the process of laying down bone?
a) Deposition
b) Resorption
c) Remodeling
d) Drift
e) Displacement
a) Deposition
What range of days if the ovum period?
10-14 days
The median nasal and maxillary processes form what adult structure?
Lateral lip and maxilla. fusion
Which term is being described: Increase in complexity; refers to transition in functional stage or activity
a) Growth
b) Development
b) Development
Which is characterized by the removal of bone?
a) Deposition
b) Resorption
c) Remodeling
d) Drift
e) Displacement
b) Resorption
How many weeks is the prenatal period?
40 weeks
What is the classic triad of submucous cleft palate?
1) bifid uvula
2) Palatal muscle diastasis
3) Notch in posterior surface of the hard palate
What type of bone formation has no cartilaginous precursors and bone is formed by periosteum and sutures under tension?
Intramembranous (cleidocranial dysplasia). Cranial vault. Premature closure of cranial sutures - apert’s and crouzon’s. Maxilla - IM
When do the maxillary processes typically fuse?
11 weeks, closure should occur starting at the incisal foramina and zipping forward and backward
Disorders in endochondral bone formation lead to what?
Achondroplasia - hypodontia, delayed eruption
What is a normal SNB angle?
78
Which is characterized by simultaneous deposition and resorption?
a) Deposition
b) Resorption
c) Remodeling
d) Drift
e) Displacement
c) Remodeling
What causes displacement of maxilla?
Growth of the cranial base. cranial base and condylar head of mandible - endochondrial bone formation
What is a normal mandibular plane angle?
32 degrees
When does the mandible have the greatest arch length?
4 years old
What area of the mandible grows by endochondrial ossification? All other areas of the mandible grow by?
Condylar region; intramembranous ossification (surface remodeling and direct apposition)
Which is characterized as a relative movement of bone through combination of deposition and resorption?
a) Deposition
b) Resorption
c) Remodeling
d) Drift
e) Displacement
d) Drift
What is the term for increase in size?
Hypertrophy
What ethnicity and gender are at higher risk for cleft?
asians and females
What range of weeks is characterized as the “fetal” period?
9 weeks to birth. Characterized by Growth. morphogenesis and differentiation
T/F: The upper lip and maxilla - fusion
The lower lip and mandible - mergence
Commisures of mouth - mergence
True
First branchial arch problems: cleft lip and palate. Treacher Collins syndrome. Hemifacial microsomia. Pierre Robin Sequence. What % of branchial anomalies are first branchial arch related?
First branchial arch anomalies represent 1% of all branchial anomalies
What are 4 characteristics of Pierre Robin sequence?
Triad:
1) Glossoptosis
2) Micrognathia
3) Cleft Palate
4) 15-25% cardiac defects
T/F: Second arch anomalies are the most common and represent 90-95% of branchial anomalies
True
What range of weeks is characterized as the “embryo”?
first 8 weeks, characterized by development
To assess craniofacial increase, which three dimensions are used?
1) Magnitude
2) Velocity
3) Direction
Sychondroses: most fuse at birth with exception of spheno-occipital and inter-sphenoidal. Which remains active during childhood?
Spheno-occipital
Apert’s is associated with what type of malocclusion?
NArrow, high palate
Hypoplastic midface (intramembranous bone malformation - maxilla+cranial vault).
Trapezoidal-shaped mouth
Cleft soft palate (30%) or bifid uvula was found in approximately 75%
Malocclusion tends to be severe with mesial molar occlusion, mandibular overjet, anterior and posterior crossbites, and severe crowding of teeth
How does the palate form? (1 word)
fusion
Which dimension is characterized by the vector of size increase as might be described on a 3D coordinate system?
a) Magnitude
b) Velocity
c) Direction
c) Direction
What is the cartilage that is characterized by prenatal mandibular development?
Meckel’s cartilage - appears during the 7th week inter and disappears by the 24th week. At weeks 10-14 secondary accessory cartilages appear (head of the condyle; coronoid process; mental protuberance)
What is the term for increase in number?
Hyperplasia
Which hypothesis revolved around the Servo system theory; somatotrophic hormone-somatomedin complex on the primary and secondary cartilages?
Petrovich’s hypothesis of craniofacial growth
What type of bone growth is characterized in the mandible?
Both intramembranous and endochondrial ossification
Which dimension is characterized by linear craniofacial increase?
a) Magnitude
b) Velocity
c) Direction
a) Magnitude
What side of the face most often has cleft lip?
left side
What type of bone growth is characterized in the maxilla?
Intramembranous ossification; apposition of bone at the sutures that connect the maxilla to the cranium and cranial base; surface remodeling
T/F: Apert syndrome is a genetic disorder characterized by the premature fusion of certain skull bones (Craniosynostosis). This early fusion prevents the skull from growing normally and affects the shape of the head and face. In addition, a varied number of fingers and toes are fused together (syndactyly)
True
What is the age range for the period of life known as Adolescence?
10-20
When do males reach skeletal maturity?
17-18 years
Which is characterized as movement of bone as a unit?
a) Deposition
b) Resorption
c) Remodeling
d) Drift
e) Displacement
e) Displacement
Maximum velocity of growth is attained approximately how many years after prepubertal onset?
2 years
What is the age range for the period of life known as Infancy?
first 2 years after birth
What is the definition of diastasis?
Separation: classic triad of the submucous cleft palate: bifid uvula+palatal muscle diastasis+notch in the posterior surface of the hard palate
What is the theory where Sicher ascribed equal value to all osteogenic tissues, cartilages, sutures, and periosteum; Sicher thought sutures were the primary growth centers
Sutural dominance theory
Which dimension is defined as the amount of change per unit time?
a) Magnitude
b) Velocity
c) Direction
b) Velocity
With growth occurs through apposition and resorption, which results in remodeling-cortical drift displacement?
a) Maxilla
b) Mandible
a) Maxilla
Which bone grows similarly to long bones?
Condyle (endochondral growth)
What is the term for increase in complexity?
Development
What is the classic triad of submucous cleft palate?
1) Bifid uvula
2) Palatal muscle diastasis
3) Notch in the posterior surface of the hard palate
What is the term for an early maturing person?
Endomorphic
When does the greatest rate of increase in all directions occur?
Birth-3 years of life
Which dimension means the vector of size increase as might be described on a 3D coordinate system?
a) Magnitude
b) Velocity
c) Direction
c) Direction
What is the week range of the embryonal period?
2-8 weeks, differentiation of tissue occurs
Bone formation that occurs in areas of pressure?
a) Intramembranous
b) Endochondral
b) Endochondral, cartilage prevursor. Achondroplasia. Cranial base. Condylar head
What part of the mandible does not grow by direct apposition of bone and surface remodeling?
The condylar region grows by endochondrial ossification
Facial growth corresponds to somatic growth, when do females reach skeletal maturity?
13.5 y - Females, female growth spurts are earlier and shorter
What is the most accepted theory of craniofacial growth?
Functional matrix theory
T/F: 34% of 3 yos have a normal occlusion
True
When should the alveolar bone graft be performed?
When the maxillary canines are entirely within bone still
What type of growth is characteristic of primary cartilage?
a) Appositional growth
b) Interstitial growth
b) Interstitial growth
Which dimension refers to the linear dimension overall?
a) Magnitude
b) Velocity
c) Direction
a) Magnitude
What is the age range for the period of life known as Childhood?
2-10
Which term is being described: passing from one form (size or number of EC number) to another
a) Growth
b) Development
a) Growth
REVIEW: The following are characterized by delayed eruption of teeth
Down's Syndrome HYPOpituitarism Cleidocranial dysplasia (may retain primary teeth until age 15) Gardener's syndrome Osteogenesis imperfecta Chondroectodermal dysplasia Delange Albright's Familial hypophosphatemia Gorlin Mucopolysaccharidoses
What type of bone formation occurs in areas of tension?
Intramembranous growth (endochondral is pressure) Maxilla, cranial vault (Apert's Crouzon, Cleidocranial dysplasia)
