A. Hypertrophy
B. Maturation
C. Accretion
D. Hyperplasia
# The concept that growth occurs along an axis from head to tail is known as which growth pattern?
A. Anteroposterior
B. Proximodistal
C. Somatic
D. Cephalocaudal
# According to Scammons' curves, which tissue system exhibits the most rapid growth during the first few years of life, followed by a plateau?
A. Genital system
B. General body growth
C. Lymphoid system
D. Neural system
# Which theory of craniofacial growth posits that growth occurs primarily due to adaptive responses of the skeletal tissues to functional demands of surrounding soft tissues and spaces?
A. Sutural theory
B. Servosystem theory
C. Cartilage theory
D. Functional Matrix Theory
# The primary mechanism for the increase in size of the cranial vault after birth is:
A. Surface remodeling on the external surface of the vault
B. Endochondral ossification at the cranial base
C. Appositional growth at the condylar cartilage
D. Intramembranous bone formation at the sutures
# Which cranial base synchondrosis typically fuses last, continuing to contribute to anteroposterior cranial base growth into late adolescence?
A. Pterygomaxillary synchondrosis
B. Spheno-ethmoidal synchondrosis
C. Intersphenoid synchondrosis
D. Spheno-occipital synchondrosis
# Forward and downward growth of the maxilla primarily occurs through:
A. Appositional growth at the alveolar processes
B. Endochondral ossification within the maxilla itself
C. Direct bone formation at the midpalatal suture
D. Bone deposition at the maxillary sutures and surface remodeling
# Which of the following is the primary mechanism for the growth of the mandible during childhood?
A. Intramembranous ossification of the corpus
B. Endochondral ossification at the condylar cartilage
C. Growth at the symphysis
D. Sutural growth at the posterior border of the ramus
# According to Lavergne and Gasson's classification, which type of mandibular rotation refers to the rotation of the basal bone relative to the cranial base?
A. Intramatrix rotation
B. Matrix rotation
C. Total rotation
D. Alveolar rotation
# A patient with a high Frankfort-Mandibular Plane Angle (FMA) and a tendency towards an anterior open bite often exhibits which of Tweed's growth patterns?
A. Type A (Average/Mesofacial)
B. Type B (Horizontal/Brachyfacial)
C. Type C (Vertical/Dolichofacial)
D. Type D (Unclassified)
# Which pharyngeal arch gives rise to the muscles of mastication and the maxilla/mandible?
A. First pharyngeal arch
B. Second pharyngeal arch
C. Third pharyngeal arch
D. Fourth pharyngeal arch
# The primary palate develops from the fusion of which embryonic structures?
A. Two lateral palatine processes
B. Nasal septum and palatal shelves
C. Frontonasal prominence and mandibular prominences
D. Two medial nasal prominences and two maxillary prominences
# At what approximate gestational age does the fusion of the secondary palate typically begin?
A. Week 4
B. Week 6
C. Week 7-8
D. Week 10
# The primary driving force for the elevation of the palatal shelves during secondary palate formation is widely attributed to:
A. Rapid bone growth within the shelves
B. Tongue growth pushing the shelves upward
C. Intrinsic mesenchymal turgor pressure due to hyaluronic acid accumulation
D. Muscle contractions within the shelves
# Programmed cell death (apoptosis) plays a crucial role in the fusion of the palatal shelves by eliminating which specific tissue?
A. Nasal septal cartilage
B. Medial edge epithelium (MEE)
C. Mesenchymal cells of the shelves
D. Oral epithelial cells on the superior surface
# Which of the following maternal conditions during pregnancy is a known environmental factor that increases the risk of cleft palate?
A. Maternal anemia
B. Use of certain anticonvulsant medications (e.g., phenytoin)
C. Maternal hypothyroidism
D. Excessive intake of Vitamin C
# The neonatal line in enamel and dentin is formed as a result of:
A. Physiological stress associated with birth
B. Genetic predisposition for enamel hypoplasia
C. Trauma during eruption of primary teeth
D. Pre-natal systemic illness
# Which of the following conditions would typically lead to a thinner or less distinct neonatal line?
A. Diabetic mother
B. Low birth weight
C. Elective Caesarean section delivery
D. Asphyxia in the newborn
# The establishment of efficient juvenile chewing is most closely associated with the eruption of which teeth?
A. Primary canines
B. Permanent first molars
C. Primary first molars
D. Primary central incisors
# Which type of bone is rapidly formed in areas of high mechanical stress or rapid bone turnover, such as during initial callus formation in fracture healing or on the tension side during orthodontic tooth movement?
A. Trabecular bone
B. Cortical bone
C. Lamellar bone
D. Woven bone
# On the tension side of the periodontal ligament (PDL) during orthodontic tooth movement, what is the primary cellular event?
A. Hyalinization of the PDL
B. Fibroblast proliferation and collagen synthesis
C. Osteoclast activation and bone resorption
D. Reduced blood flow and cell necrosis
# Dental age is best determined by assessing the developmental stage of which of the following?
A. Tooth eruption and calcification stages
B. Skeletal maturation in the hand-wrist radiograph
C. Cervical vertebrae maturation stages
D. Chronological age
# The peak in mandibular growth velocity typically occurs in males:
A. Before the peak in statural height
B. Simultaneously with the peak in statural height
C. During early childhood (age 5-7)
D. Approximately 1-2 years after the peak in statural height
# Björk's implant studies revealed that the mandible grows primarily by:
A. Remodeling at the symphysis only
B. Surface apposition on the anterior border of the ramus and resorption on the posterior border
C. Bone deposition at the condylar cartilage and remodeling of the ramus and corpus
D. Sutural growth analogous to the maxilla
# The 'V-principle' of growth, described by Enlow, states that bone growth occurs on the inner surface and deposition on the outer surface in areas shaped like a 'V'. This is evident in the growth of the:
A. Mandibular condyle
B. Mandibular ramus (at the posterior border) and maxillary arch
C. Cranial vault
D. Nasal bone
# The pharyngeal pouch that gives rise to the palatine tonsil is the:
A. First pharyngeal pouch
B. Second pharyngeal pouch
C. Third pharyngeal pouch
D. Fourth pharyngeal pouch
# In a child with a 'gummy smile' due to excessive vertical maxillary growth, what change in lip position is often observed during adolescence with normal growth?
A. Shortening of the upper lip vertical dimension
B. Increased lower lip eversion
C. Increased upper incisor display at rest
D. Decreased gingival display during smiling
# Which type of growth involves an increase in the size of individual cells, without an increase in cell number?
A. Hypertrophy
B. Hyperplasia
C. Accretion
D. Remodeling
# The timing of orthodontic treatment, especially for growth modification, is often correlated with:
A. Chronological age alone
B. Dental age only
C. Skeletal age (e.g., hand-wrist or cervical vertebrae maturation)
D. Weight and height percentile
# The concept of 'leeway space' in the mixed dentition refers to the size difference between:
A. Primary canine and permanent canine
B. Primary canines and first and second molars combined, compared to their permanent successors (canine and first and second premolars)
C. The arch perimeter before and after eruption of permanent molars
D. Primary incisors and permanent incisors
# Which of the following describes the growth of the nasal septum?
A. Primarily intramembranous ossification
B. Its growth ceases entirely by age 5
C. Undergoes extensive sutural growth
D. A major determinant of midfacial growth
# The initial growth of the cranial base occurs primarily through which type of ossification?
A. Endochondral ossification
B. Sutural growth
C. Appositional growth
D. Intramembranous ossification
# The growth of the upper lip during adolescence, particularly its vertical dimension, tends to lead to:
A. A more everted lower lip
B. Reduced display of gingiva during a full smile
C. Increased exposure of the maxillary incisors at rest
D. A deeper mentolabial sulcus
# What is the approximate percentage of an individual's final adult brain size achieved by age 6-7 years?
A. 50%
B. 90-95%
C. 75%
D. 100%
# During the mixed dentition phase, the eruption of permanent mandibular incisors often leads to a transient crowding due to:
A. Insufficient leeway space in the mandible
B. Early loss of primary molars
C. Lack of intercanine width increase
D. Larger mesiodistal width of permanent incisors compared to primary incisors
# The concept that the maxilla moves downward and forward, while the mandible grows at its condyles and remodels to accommodate this displacement and its own growth, is best described by:
A. Servosystem theory
B. Combination of displacement and growth at independent sites
C. Sutural theory
D. Purely genetic control
# Remodeling of the chin (mental protuberance) during growth involves:
A. Primarily vertical growth with no anteroposterior change
B. Apposition on the anterior surface and resorption on the inferior border
C. Active cartilaginous growth
D. Predominant resorption on the anterior surface
# The general S-shaped growth curve, characteristic of overall body growth, represents which type of growth?
A. Genital growth
B. Lymphoid growth
C. Skeletal and muscular growth
D. Neural growth
# What is the primary factor driving the downward displacement of the maxilla during growth?
A. Bone apposition on the oral surface of the palatal vault and at the circummaxillary sutures
B. Vertical eruption of mandibular molars
C. Growth of the nasal septum
D. Resorption on the orbital floor
# The term 'maturation' in the context of growth and development refers to:
A. Genetic determination of final size
B. An increase in size due to addition of cells
C. Qualitative changes that enable a higher level of function
D. Quantitative changes in size or number
# The secondary palate contributes to the formation of which part of the palate?
A. The alveolar process for the maxillary incisors
B. The hard palate posterior to the incisive foramen and the entire soft palate
C. The philtrum of the upper lip
D. The premaxilla
# Which developmental anomaly is associated with a deficiency in neural crest cell migration into the first and second pharyngeal arches, leading to hypoplasia of the zygomatic bones, mandible, and external ears?
A. Van der Woude syndrome
B. DiGeorge syndrome
C. Treacher Collins syndrome (Mandibulofacial Dysostosis)
D. Pierre Robin Sequence
# The normal reduction in arch length from the primary dentition to the permanent dentition, particularly in the posterior segments, is known as:
A. Terminal plane relationship
B. Primate space
C. Incisor liability
D. Leeway space
# Which of the following describes the growth direction of the mandibular ramus?
A. Does not significantly change in size post-natally
B. Grows primarily vertically by condylar resorption
C. Grows primarily in an anterior direction by resorption on its posterior border
D. Grows posteriorly by apposition on its posterior border and resorption on its anterior border
# The 'functional matrix' in the functional matrix theory refers to:
A. The genetic blueprint of the bone itself
B. The soft tissues and spaces surrounding the skeletal unit that influence its growth
C. The cartilaginous growth centers
D. The sutures where bone deposition occurs
# Which of the following is an example of an autosomal dominant genetic syndrome commonly associated with cleft lip and/or palate?
A. Cri-du-chat syndrome
B. DiGeorge syndrome
C. Van der Woude syndrome
D. Down syndrome (Trisomy 21)
# The growth of the dental arches, particularly the increase in intercanine width, is primarily completed by what age?
A. Age 6-7 years (eruption of permanent first molars)
B. Age 10-12 years (eruption of permanent canines)
C. Age 15-16 years (end of pubertal growth spurt)
D. Age 3-4 years
# The growth of the dental arches, particularly the increase in intercanine width, is primarily completed by what age?
A. Age 6-7 years (eruption of permanent first molars)
B. Age 10-12 years (eruption of permanent canines)
C. Age 15-16 years (end of pubertal growth spurt)
D. Age 3-4 years
# What is the primary factor that causes the forward and downward displacement of the entire maxilla during growth?
A. Intrinsic growth of the maxillary bones themselves
B. Bone apposition at the various sutures connecting the maxilla to the cranial base and other facial bones
C. Remodeling of the alveolar process in response to tooth eruption
D. Growth of the nasal septum and the brain, pushing the maxilla passively
# The earliest sign of puberty, and a key indicator for the pubertal growth spurt in males, is often considered to be:
A. Peak height velocity
B. Increase in testicular volume
C. Appearance of facial hair
D. Onset of menarche
# Which of the following describes the 'growth spurt'?
A. A sudden and rapid increase in growth rate during adolescence
B. Growth that occurs only during sleep
C. Growth that is purely genetic and unaffected by environmental factors
D. A period of slow and steady growth throughout childhood
# The period of growth from birth to the eruption of the first permanent molar is known as:
A. Pre-pubertal growth
B. Childhood growth
C. Adolescence
D. Infancy and early childhood
# The concept of 'functional space' in the Functional Matrix Theory refers to:
A. The intraoral space for tooth eruption
B. The volume occupied by organs like the brain or eyes, which influences the growth of surrounding bones
C. The space between individual cells in bone tissue
D. The space available for orthodontic appliances
# Which pharyngeal arch's arterial component typically contributes to the formation of the arch of the aorta and the pulmonary artery?
A. First pharyngeal arch artery
B. Second pharyngeal arch artery
C. Third pharyngeal arch artery
D. Sixth pharyngeal arch artery
# The growth of the eye orbits is primarily influenced by the growth of the eyeballs themselves. This is an example supporting which growth theory?
A. Servosystem theory
B. Functional Matrix Theory
C. Sutural theory
D. Cartilage theory
# The average age for the fusion of the intersphenoid synchondrosis is:
A. Birth to 1 year
B. 20+ years
C. 13-17 years
D. 7-8 years
# Which of the following is considered a primary growth center for the cranial base?
A. Condylar cartilage
B. Nasal septum
C. Spheno-occipital synchondrosis
D. Pterygopalatine suture
# In the development of the tongue, the posterior one-third (pharyngeal part) is primarily derived from which pharyngeal arch?
A. Sixth pharyngeal arch
B. Third and fourth pharyngeal arches
C. Second pharyngeal arch
D. First pharyngeal arch
# What is the primary factor thought to initiate the shift from vertical to horizontal growth of the palatal shelves during secondary palate formation?
A. Increased blood supply to the palatal shelves
B. Increased mitotic activity on the oral side of the shelves
C. Head extension and descent of the tongue
D. Growth of the nasal septum pushing them horizontally
# The earliest clinical sign of dental development, which can be observed with the naked eye, is usually the eruption of the:
A. Primary first molars
B. Permanent first molars
C. Maxillary central incisors
D. Mandibular central incisors
# The overall growth of the cranial base, in terms of length, is primarily due to growth at the:
A. Pterygomaxillary suture
B. Spheno-occipital synchondrosis
C. Foramen magnum
D. Cranial sutures of the vault
# What is the approximate average age for the completion of the ossification of the spheno-ethmoidal synchondrosis?
A. 3 years
B. 7-8 years
C. 15 years
D. Birth
# The Servosystem theory, primarily applied to mandibular growth, suggests that mandibular growth is a feedback mechanism regulated by:
A. Direct hormonal stimulation on the mandibular body
B. The growth of the nasal septum
C. Genetic factors alone
D. Changes in occlusal contact and subsequent condylar response
# Which type of growth involves an increase in extracellular substance, such as the deposition of bone matrix by osteoblasts?
A. Resorption
B. Hyperplasia
C. Hypertrophy
D. Accretion
# The peak height velocity (PHV) is a crucial indicator for orthodontic treatment timing because it generally precedes or coincides with:
A. The eruption of all permanent teeth
B. The complete fusion of all cranial sutures
C. The period of maximum mandibular growth
D. The end of all craniofacial growth
# Which of the following bones is primarily formed by intramembranous ossification?
A. Vertebrae
B. Femur
C. Sphenoid bone (cranial base part)
D. Parietal bone (cranial vault)
# The skeletal age assessment method that analyzes changes in the morphology of the cervical vertebrae on a lateral cephalometric radiograph is known as:
A. Hand-wrist analysis (e.g., Greulich and Pyle Atlas)
B. Dental calcification stages (e.g., Nolla's stages)
C. Cervical Vertebrae Maturation (CVM) method
D. Björk's implant method
# An early loss of a primary second molar in the mandibular arch can lead to a reduction in arch length for the eruption of the permanent second premolar due to:
A. Distal drift of the permanent first molar
B. Mesial drift of the permanent first molar
C. Mesial shift of the primary canine
D. Over-eruption of the opposing molar
# The cartilaginous growth plates located within the long bones, responsible for their increase in length, are called:
A. Synchondroses
B. Epiphyseal plates
C. Sutures
D. Periosteum
# Which of the following statements about pubertal growth spurt is generally true?
A. It involves primarily only an increase in height.
B. It occurs earlier in males than in females.
C. It ceases entirely by age 14 in both sexes.
D. It is characterized by a rapid acceleration in growth rate.
# Which of the following cranial base synchondroses remains active longest postnatally, contributing significantly to anteroposterior facial growth?
A. Intersphenoid
B. Spheno-ethmoidal
C. Spheno-occipital
D. Occipito-mastoid
# The primary cause of the change from a straight terminal plane to a Class I molar relationship in the permanent dentition is:
A. Excessive mandibular growth
B. Distal shift of maxillary molars
C. Late mesial shift due to leeway space utilization
D. Early mesial shift due to primate space closure
# Which cranial nerve innervates the muscles derived from the second pharyngeal arch?
A. Vagus nerve (CN X)
B. Trigeminal nerve (CN V)
C. Facial nerve (CN VII)
D. Glossopharyngeal nerve (CN IX)
# The increase in the width of the dental arches, particularly the posterior segments, is primarily due to:
A. Appositional growth on the lingual surfaces of the alveolar processes
B. Growth at the midpalatal suture and apposition on the buccal surfaces of the alveolar processes
C. Resorption on the buccal surfaces of the alveolar processes
D. Passive displacement of the teeth in a buccal direction
# In females, the peak in mandibular growth velocity typically occurs:
A. During early childhood (age 5-7)
B. Before or concurrent with menarche
C. Approximately 2 years after peak height velocity
D. After menarche
# Which of the following genetic factors is most commonly associated with non-syndromic cleft lip and palate?
A. Chromosomal abnormalities (e.g., Trisomy 21)
B. A single gene mutation with Mendelian inheritance
C. Multifactorial inheritance (interaction of multiple genes and environmental factors)
D. Maternal age being over 40 years
# The growth of the overall facial height from childhood to adulthood is proportionally more in the:
A. Upper face (forehead region)
B. Cranial vault
C. Posterior cranial base
D. Midface and lower face
# What is the term for the growth changes that occur in the craniofacial complex to compensate for and maintain normal functional relationships (e.g., occlusion) despite underlying skeletal growth discrepancies?
A. Compensatory growth and remodeling
B. Primary displacement
C. Genetic programming
D. Intrinsic growth
# The primary role of the dental follicle (sac) during tooth development is to:
A. Induce odontoblast differentiation
B. Guide tooth eruption path
C. Contribute to cementum, periodontal ligament, and alveolar bone formation
D. Form enamel
# The term 'remolding' in bone growth refers to:
A. The genetic determination of skeletal size
B. Growth by increase in cell number only
C. Passive displacement of bones due to adjacent growth
D. The continuous process of bone formation and resorption that changes the shape, size, and proportion of bones
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