Todd: growth: increase in size Development: progress toward maturity Krogman: increase in size : change in proportion and progressive complexity Meridth: segmental anatomic and physiologic changes taking place from beginning of prenatal life to senility Moyers: quantitative aspect of biologic development per unit of time Moss: change in any morphologic parameter which is measurable. By bone remodeling there is several changes in: size, shape, proportion, relationship with adjacent structure. Maxillary sinus: Like other paranasal sinuses are rudimentary at birth, they grew slowly until the age of 6 -7 years, then they enter the spurt specially the maxillary sinus. At 8 years it has a pyramidal form that will length after eruption of canine and last molar Function of sinuses: 1- Lightening of skull weight 2- Resonance of voice 3- Conditioning of air 4- Craniofacial protection Fate of pharyngeal arches: Mesodermal core of each pharyngeal arch and neural crest cells which migrate into the arches differentiate into: 1- Skeletal elements 2- Vascular elements 3- Nervous elements 4- Muscular elements Growth center Growth site Growth indicator Growth adjustor Pushes a part Pulled a part Tissue separating force No tissue separating force As: nasal cartilage Spheno occipital synchondrosis As: condyle and suture Synchondrosis Epiphyseal plate 1- Cranial base Long bones 2- Interstitial growth Appositional 3- Bone replaced on both sites so it considered as double action of epiphyseal plate At one site Center of ossification of maxilla start around the anterior superior dental arch of inferior orbital nerve and spread: Anterior: --- premaxilla Posterior ----zygomatic process of maxilla Superior ---- frontal process of maxilla Inferior: ------periosteum of alveolar process of maxilla Medial: ------- hard palate N: B: Types of bone remodeling: 1- Biomechanical remodeling: continuous deposition and removal of ions to maintain the mineral content 2- Growth remodeling: constant replacement of bone during childhood 3- Haversian remodeling: cortical reconstruction as primary vascular bone is replaced 4- Regeneration and reconstruction of bone following pathology or trauma Endochondral bone formation: = on the cartilage surface, there is -------chondroblast arranged in parallel columns while the matrix is being deposited among the columns of cells = chondroblast ----- hypertrophic and there is a lacuna become wide and so there is small strand of matrix between each cell = this matrix starts of mineralization after appear of nuclei then chondroblast ----------- chondrocyte ---------- degenerative and disappear after loss of nutrition fluids. = after time there is vascular invasion so; perichondrium changed into periosteum and the osteoblast start its action for osteoid formation = by this process there is a formation of central core of mineraliz

1. 1
Dr. Mohammed Alruby
Growth and development
of craniofacial skeleton
Prepared by
Dr. Mohammed Alruby
Definitions

2. 2
Dr. Mohammed Alruby
Growth center and sites
Facial processes
Types of bone and bone cells
Growth of cranial vault
Growth of cranial base
Growth of maxilla
Growth of mandible
Age changes
Methods of studying bone growth
Growth indicators
Todd: growth: increase in size

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Dr. Mohammed Alruby
Development: progress toward maturity
Krogman: increase in size
: change in proportion and progressive complexity
Meridth: segmental anatomic and physiologic changes taking place from beginning of prenatal
life to senility
Moyers: quantitative aspect of biologic development per unit of time
Moss: change in any morphologic parameter which is measurable.
By bone remodeling there is several changes in: size, shape, proportion, relationship with adjacent
structure.
Maxillary sinus:
Like other paranasal sinuses are rudimentary at birth, they grew slowly until the age of 6 -7 years,
then they enter the spurt specially the maxillary sinus. At 8 years it has a pyramidal form that will
length after eruption of canine and last molar
Function of sinuses:
1- Lightening of skull weight
2- Resonance of voice
3- Conditioning of air
4- Craniofacial protection
Fate of pharyngeal arches:
Mesodermal core of each pharyngeal arch and neural crest cells which migrate into the arches
differentiate into:
1- Skeletal elements
2- Vascular elements
3- Nervous elements
4- Muscular elements
Growth center Growth site
Growth indicator Growth adjustor
Pushes a part Pulled a part
Tissue separating force No tissue separating force
As: nasal cartilage
Spheno occipital synchondrosis
As: condyle and suture
Synchondrosis Epiphyseal plate
1- Cranial base Long bones
2- Interstitial growth Appositional
3- Bone replaced on both sites so it
considered as double action of
epiphyseal plate
At one site
Center of ossification of maxilla start around the anterior superior dental arch of inferior orbital
nerve and spread:
Anterior: --- premaxilla

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Dr. Mohammed Alruby
Posterior ----zygomatic process of maxilla
Superior ---- frontal process of maxilla
Inferior: ------periosteum of alveolar process of maxilla
Medial: ------- hard palate
N: B:
Types of bone remodeling:
1- Biomechanical remodeling: continuous deposition and removal of ions to maintain the
mineral content
2- Growth remodeling: constant replacement of bone during childhood
3- Haversian remodeling: cortical reconstruction as primary vascular bone is replaced
4- Regeneration and reconstruction of bone following pathology or trauma
Endochondral bone formation:
= on the cartilage surface, there is -------chondroblast arranged in parallel columns while the
matrix is being deposited among the columns of cells
= chondroblast ----- hypertrophic and there is a lacuna become wide and so there is small strand
of matrix between each cell
= this matrix starts of mineralization after appear of nuclei then chondroblast -----------
chondrocyte ---------- degenerative and disappear after loss of nutrition fluids.
= after time there is vascular invasion so; perichondrium changed into periosteum and the
osteoblast start its action for osteoid formation
= by this process there is a formation of central core of mineralized cartilage surrounded by matrix
of bone -------- spongiosa---------- resorption of mineralized cartilage -------- degenerate space for
vascular invasion ----------- by time is filled by red bone marrow
Mandible:
Have two different ways of mandibular formation:
1- Primary intramembranous calcification center arise lateral to each half of Meckel’
cartilage around the nerve and blood supply: to start ossification spread ventrally and
laterally to forms body and ramus of mandible.
Meckel’ cartilage after time disappear except: incus, mellus, mental ossicles that
incorporated to mental region
2- Accessory cartilage:
a- Condyle center: starts as separate part to form condyle and posterior part of ramus
above inferior nerve
b- Coronoid center: form coronoid and anterior part of ramus above the inferior alveolar
nerve
c- Mental ossicles:
Types of bone:
1- Lamellar: collagen fibers run parallel to each other in lamellae as compact and spongy
2- Non lamellar: woven bone (embryonic bone)
3- Bundle bone: found adjacent to periosteum give attachment to ligament and tendon
Synchondrosis: layer of cartilage connect bone to bone

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Dr. Mohammed Alruby
Syndesmosis: layer of CT connect bone to bone
Synostosis: bridge of calcified tissue connect bone to bone
Cartilaginous area of facial skeleton:
1- Mandibular condyle
2- Nasal septum
3- Spheno-occipital synchondrosis at base of skull
Types of bone cells:
1- Osteoblast
2- Osteoclast
3- Osteocyte
4- Bone lining cells: will have major impact on Ca metabolism within the body
Cranial vault
Anatomy: 2 frontal bone------- metopic suture
2 parital bone --------sagittal suture
1 occipital bone
Coronal suture = lambdoid suture
Origin: intramembranous
Width: coronal suture and lambdoid suture
Cranial fontanelles; anterior: bregma: 2---3 years of life
Posterior: lambda: 1 years of life
2 anterior lateral: sphenoid petrion -------- close soon after birth
2 posterior lateral: mastoid sterion ---------close soon after birth
Cranial base
Origin: intramembranous and endochondral bone formation
Anatomy: anterior cranial base: nasion to sella
Posterior cranial base: sella to basion
Sutures:
1- Front- ethmoidal suture
2- Spheno-ethmoidal synchondrosis --------- 6 -7 years of age
3- Sphno-occipital synchondrosis ------------ 20 years of age
4- Inter-sphenoid ------- close before birth
5- Inter-occipital ------- 3 -5 years of age
Anterior-posterior direction:
= nasion to foramen cecaum: ----- thickness of frontal bone
= foramen cecaum to sella turcica; ------- include the length of cripriform plate of ethmoid which
is neural growth (eruption of U6 and L6)
= sella turcica to basion ------ skeletal growth (eruption of U8 and L8)
= cranial base complete more than half of its growth by age of 8 years
Vertical direction:

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Dr. Mohammed Alruby
At occipital bone, frontal bone, greater wing of sphenoid bone
Lateral direction: width:
7 to 8 years increase transverse size follow the neural pattern
Maxilla
Origin: intra-membranous bone formation
Formed of
1- Bone:
Palatal bone
Maxillary bone
Vomer
Malar bone
Zygomatic bone
Pterygoid plate of ethmoid
2- Sutures:
Fronto-maxillary suture
Zygomatico-maxillary suture
Zygomatico frontal suture
Zygomatico temporal suture
Fronto-nasal suture
Pterygo- palatine suture
Height:
Half of growth by displacement due to anterior cranial base and nasal cartilage due to respiratory
demands
The other half, by drift, reposition on the nasal floor and deposition of the palate and alveolar
process.
So the nasal floor become in low level than orbital floor due to more reposition on nasal floor (V
principle) and eruption of teeth increase the alveolar height
Width:
Sutures, appositional, direction of eruption of teeth
Length:
1- Displacement to cranial base
2- Pnumatization of maxillary sinus
3- Deposition of bone at tuberosity area
4- Give chamber of eruption of 6,7 together with primary displacement
N: B:
Vomer:
One of unpaired facial bone of skull located at mid sagittal line
Articulate with sphenoid, ethmoid, right and left palatine bone, right and left maxillary bone
Vomer articulate with six bones:
Two with cranium: sphenoid and ethmoid
Four with face: two maxillary bone and two palatine bone. And also articulate with septal cartilage
of nose
Mandible

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Dr. Mohammed Alruby
Origin: endochondral and intramembranous bone formation
Endochondral sites: condyle, coronoid, mental ossicles, symphyseal cartilage
Sites of mandibular growth:
1- Symphysis: depend on symphyseal suture until 11 years and after that fusion complete
2- Condyle: appositional growth of cartilage at the perichondrium of condyle, it is the major
site of growth
3- Processes:
a- alveolar process
b- Muscular process:
1- Gonial process: --- masseter muscle and medial pterygoid
2- Coronoid process: temporalis muscle
3- Mental process: mentalis muscle
Height:
Surface apposition on the lower border of mandible
Development of alveolar arch with eruption of teeth
Width:
Symphyseal cartilage growth
V principle
Remodeling from inner and outer surface of mandible
Length:
Secondary displacement
Surface apposition
Relocation at ramus area
Mental foramen: early in life it is under mesial cusp of the 1st
deciduous molars, in adult is below
and between 1st
and 2nd
premolars due to backward and outward inclination of canal
Role of Meckel’s cartilage:
1- It guides the development of mandible forming morphogenic template which exert tension
on the ossification center
2- It participates in the development of symphysis menti
3- It serves as a means of attachment of the muscles of mastication and tongue muscles
4- It is involved in the development of middle ear ossicles
5- Contribute in the formation of articular disc of TMJ
6- It is important in shaping the palate
Section of Meckel’s cartilage regard to their position:
1- Proximal or tympanic portion give raise to the mellus and incus (Richary et al 1965)
2- Anterior process of mellus formed from osgonial
3- Portion from mellus of middle ear and lingualla of mandible is transformed into spheno-
mandibular ligament
4- Spin of sphenoid bone
5- Mental ossicles
Age change in the mandible:

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Dr. Mohammed Alruby
At birth:
= bone, mere shell containing sockets of two incisors, canine and two deciduous molars
= mandibular canal: large size and run near the lower border of the bone
= mental foramen opens beneath the socket of 1st
deciduous molar
= condyle portion in the line with the body
= coronoid process: large size and project above the level of condyle
Childhood:
= two segment of bone become joined at symphysis from below to upward in 1st
year, but trace of
separation may be present at 2nd
year
= body become elongated in whole length, but more especially behind the mental foramen to
provide space for the three molar developed
= depth increase to allow for roots (increase vertical growth)
= increase thickening of bone at sub-dental portion which enable the jaws to withstand the action
of muscle
= mandibular canal is just above the mylohyoid line
= mental foramen occupies the position that usually in adult
= mandibular angle become less obtuse 140 degrees
Adulthood:
= mental foramen opens midway between the upper and lower border of bone
= mandibular canal: parallel to mylohyoid line
= mandibular angle: 110 – 120 degrees
Old age:
= bone reduce in size with loss of teeth
= mandibular canal with mental opening from it and close to the alveolar border
= ramus: oblique in direction
= mandibular canal: 140
= neck of condyle: less bent backward
Methods of studying craniofacial bone growth
1- Vital staining:
In 1736 Belchier reported that bones of animals who had eaten the madder plant were stained red
color
In 1739 Duhamel fed madder plant to animal, withheld it for a period prior to sacrifice as a result,
the bone contained a band of red stain followed by unstained band
Alizarin red was the essential dye for madder plant
There are another dyes as: procion compound, trypan blue, acid alizarin blue, antibiotic
tetracycline
Value of such vital dyes:
1- Describe the pattern of postnatal bone deposition over an expected period in one animal
2- The manner in which the bone is laid out
3- The sites of growth
4- The direction of growth
5- The relation duration at different sites
2- Radio Isotopes:

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Dr. Mohammed Alruby
Used as un-vivo marker
Such labelled material is injected and then after time located within the growing bone by means
of:
- Giger counter
- Auto-radiographic technique
3- Implant:
Bjork method: implanting the bits of titanium into growing bone of animals or human being, this
will serve as reference marker during several cephalometric analysis
Implant growth studies: Bjork 1969:
Involve implanting of small bits of biological inert alloy into growing bone:-- titanium—1.5mm
length and 0.5 diameter
In maxilla:
- Hard palate behind the deciduous canine (prior eruption of maxillary permanent incisors)
- Below anterior nasal spin after eruption of maxillary incisors
- Two implant on either side of zygomatic process of maxilla
- Border between hard palate and alveolar process medial to 1st
molar
In mandible:
- Anterior aspect of symphysis in midline below root tips
- Two pins on right side of mandibular body, one under 1st
premolar and one below 2nd
premolar or 1st
molar
- One pin on the external aspect of the right ramus at the level of occlusal surface of molars
4- Comparative anatomy:
Significant contribution to the knowledge of human facial growth have been provided through
comparison with other species
5- Craniometry:
Measurements of skull to determine its characteristic related to sex, race, or body type
6- Genetic studies:
Used to study parents’ child relationship
There are different genetic factors in the dentofacial development
The problem is to identify the specify, site, timing, and mechanism of any such genetic control
7- Natural markers:
The persistence of certain developmental features of bone has led to their use as natural markers
using certain radiograph
- Trabecula
- Nutrient canal
- Incremental lines (lines arrested growth)
This can use for reference to study deposition, resorption, and remodeling
8- Removal of parts to study growth:
As cartilaginous nasal septum and its effect on the forward growth
9- Histologic study:

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Dr. Mohammed Alruby
Study matrix and its density
Beam of x-ray and microscopic level is passed through un-calcified thin section of bone placed
over sensitive emulsion
Different passage of ray, record on the film as varying ---- black, gray, while colors
10-Split line technique: Benninghoff 1925
Bone is partially decalcified making it soft enough and punched with needle
India ink inserted in these split to make them visible and fixes permanently (pattern of trabecula)
Growth indicators
History:
1896: Sydney Rowand record hand & wrist x-ray after 6 months from discover x-ray in London
1900: Pryor Rotch
1928: Helman and Haward
1936: Flory (Sesamoid) stage of begins calcification
1- Hand & wrist radiograph:
= Using left hand or use 1st
,2nd
, 3rd
finger on the front of cephalometric film in attempt to reduce
the dose of radiation
= Most common published by Greulish and Pyle in 1959
= TW2 (Tuner and white house 2) make developmental score with twenty bones on hand and wrist
= the long axis of third finger in direct line with axis of forearm
= the thumb is placed in the most comfortable natural degree of rotation with its long axis making
30 degree with 1st
finger
= tube is centered above the third metacarpal at a tube film distance of 30 inches or 75cm
= hand and wrist views may be interpreted by many ways:
a- Either comparing the radiograph with series of standard films represent normal children at
different age
b- Time of occurrence of certain ossification events in relation to spurte growth
c- By assessing score to developmental age of 20 bones in hand and wrist (TW2 1975)
(phalanx, radius, ulna)
Methods:
- Greulish Pyle 1959
- TW2 1975
- Singer method 1980
- Hagg and Taranger 1980
- Fishman
2- Adductor sesamoid:
Sesamoid of the adductor bravis muscle at the metacarpo-pharyngeal joint of thumb
Sesamoid bone: bone embedded within tendon or muscle, it is derived from Latin ward (sesamum)
(seasamy seads) due to small size. Sesamoid bone found on joint throughout the body:
a- Knee: the patella
b- Hand --- two sesamoid, most used that present within the tendon of adductor pollicis
c- Wrist: the pisiform of the wrist within tendon of flexor carpi ulnaris
d- In foot: 1st
metatarsal

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Dr. Mohammed Alruby
e- In neck
Described by Champan 1972 as the following:
ASO: no ossification
AS1: pin point ossification
AS2: ossification more than pin point but not identified
AS3: seed shape: well defined outline, measured about 3mm x2mm ------- short female and 3mm x
4mm -------- long male
3- Cervical vertebrae:
Lampanraski 1972
Hassel and Farman 1995
Fishman 1982
Baccelli et al 2000
Franchi and Macnamara
Anatomy:
C1: atlas:
Known as atlas vertebrae is the 1st
of upper most of 33 vertebrae of spinal column of cervical
vertebrae
1st
, 2nd
vertebrae are distinct from the other true vertebrae or removable vertebrae below them
within the neck
C2: axis:
2nd
cervical vertebrae, 2nd
upper most vertebrae
Name axis derived from its role in allowing the head to rotate from its support at C1 where the
skull attach the neck
C3:
Setting below the C2 axis, from C3 to C6 are grouped together
Composed of:
- Vertebral arch: protect spinal cord
- Ventral body centrum: provide strength, protection and mobility to the body
C4:
Small in relation to the other vertebrae but with large vertebral foramen for passage of nerves of
spinal
Cervical vertebrae maturation: CVM:
Depend on: C2, C3, C4
Definition of cervical vertebrae maturation stages:
Cs1: the lower border of all 3 vertebrae C2 – C4 are flat
The bodies of C3 and C4 are trapezoid in shape
Cs2: a concavity is present at the lower border of C2 in 80% of cases. The bodies of both C3 and
C4 are trapezoid in shape
Cs3: concavities at the lower border of both C2 and C3 are present. The bodies of C3 and C4 can
be either trapezoid or rectangular horizontal in shape.
Cs4: concavities at lower border of C2, C3 and C4 now present, the bodies of C3 and C4 are
rectangular horizontal in shape
Cs5: the concavities at lower border of C2, C3, C4 still present at least body of C3 or C4 square
in shape. If not square the body of others cervical vertebrae still rectangular horizontal
Cs6: the concavities at lower border of C2, C3 and C4 still present

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Dr. Mohammed Alruby
At least body of C3 or C4 is rectangular vertical in shape if not rectangular is square
4- Frontal sinus:
Rossow 1991: analysis the size of frontal sinus highest point and lowest point and relate to SN line
5- Dental development:
1- Nolla calcification stages 1960
2- Bjork and Hellman 1967
3- Hagg and Taranger 1982
4- Damaergian 1982
5- Chertknow 1980: calcification stage of permanent lower canine at the close to the
ossification on sesamoid of adductor
6- Lower third molar development:
a- Tooth germ visible
b- Cusp formation
c- Crown formation complete
d- Half of root formed
e- Root formation complete but apex not closed
7- Other indicators:
a- Body weight and hight
b- Chronological age
c- Growth velocity
d- Concentration of growth hormone