SKULL
It is skeletal framework of the head.
BONES OF SKULL
The skull consists of 22 bones, excluding the ear ossicles.
PAIRED UNPAIRED
Infra nasal conchae Frontal
Parietal Vomer
Temporal Ethmoid
Zygomatic Sphenoid
Maxillary Occipital
Nasal Mandible
Lacrimal
Palatine
DIVISION OF SKULL
There is confusion about exactly what the term skull means. It may mean the cranium
(which includes the mandible) or the part of the cranium excluding the mandible. There
has also been confusion because some people have used the term cranium or only
neurocranium. FICAT has decided to use the Latin term cranium, or the skeleton of the
head.
The skull is divided into 2 parts:(According to gray's anatomy)
1,Cranium which is further divided into:
A, Neurocranium, which consist of two parts:
a,an upper domed part (the calvaria or skull cap), which covers the cranial cavity
containing the brain.
The bones forming the calvaria are mainly the paired parietal bones and temporal bones,
and parts of the unpaired frontal,and occipital bones
b,Basicranium( floor of cranial cavity). The bones forming the base of the cranium are
mainly parts of the sphenoid, temporal, and occipital bones.
B. viscerocranium, the facial skeleton.The bones forming the facial skeleton are the paired
, nasal bones, palatine bones, lacrimal bones, zygomatic bones, maxillae, inferior nasal
conchae and ethmoid and the unpaired vomer.
2,Mandible.
METHODS OF STUDY OF SKULL
The whole skull can be studied from the outside or externally in different views:
a. Superior view or norma verticalis.
b. Posterior view or norma occipitalis.
c. Anterior view or norma frontalis.
d. Lateral view or norma lateralis.
e. Inferior view or norrna basalis.
The whole skull can be studied from the inside or internally after removing the roof of the
calvaria or skullcap:
a. Internal surface of the cranial vault.
b. Internal surface of the cranial base which shows a natural subdivision into anterior, middle
and posterior cranial fossae.
The skull can also be studied as individual bones.
ANATOMICAL POSITION OF SKULL
The skull can be placed in proper orientation by considering any one of the two planes.
1 Reid's base line is a horizontal line obtained by joining the infraorbital margin to the centre of
the external acoustic meatus, i.e. auricular point.
2 The Frankfurt's horizontal plane of orientation is obtained by joining the infraorbital margin
to the upper margin of the external acoustic meatus
SKULL JOINT
The joints in the skull are mostly sutures, a few primary cartilaginous joints and three pairs of
synovial joints. Two pairs of synovial joints are present between the ossicles of middle ear. One
pair is the largest temporomandibular joint. Sutures are:
Plane - internasal suture
It is skeletal framework of the head.
BONES OF SKULL
The skull consists of 22 bones, excluding the ear ossicles.
PAIRED UNPAIRED
Infra nasal conchae Frontal
Parietal Vomer
Temporal Ethmoid
Zygomatic Sphenoid
Maxillary Occipital
Nasal Mandible
Lacrimal
Palatine
DIVISION OF SKULL
There is confusion about exactly what the term skull means. It may mean the cranium
(which includes the mandible) or the part of the cranium excluding the mandible. There
has also been confusion because some people have used the term cranium or only
neurocranium. FICAT has decided to use the Latin term cranium, or the skeleton of the
head.
The skull is divided into 2 parts:(According to gray's anatomy)
1,Cranium which is further divided into:
A, Neurocranium, which consist of two parts:
a,an upper domed part (the calvaria or skull cap), which covers the cranial cavity
containing the brain.
The bones forming the calvaria are mainly the paired parietal bones and temporal bones,
and parts of the unpaired frontal,and occipital bones
b,Basicranium( floor of cranial cavity). The bones forming the base of the cranium are
mainly parts of the sphenoid, temporal, and occipital bones.
B. viscerocranium, the facial skeleton.The bones forming the facial skeleton are the paired
, nasal bones, palatine bones, lacrimal bones, zygomatic bones, maxillae, inferior nasal
conchae and ethmoid and the unpaired vomer.
2,Mandible.
METHODS OF STUDY OF SKULL
The whole skull can be studied from the outside or externally in different views:
a. Superior view or norma verticalis.
b. Posterior view or norma occipitalis.
c. Anterior view or norma frontalis.
d. Lateral view or norma lateralis.
e. Inferior view or norrna basalis.
The whole skull can be studied from the inside or internally after removing the roof of the
calvaria or skullcap:
a. Internal surface of the cranial vault.
b. Internal surface of the cranial base which shows a natural subdivision into anterior, middle
and posterior cranial fossae.
The skull can also be studied as individual bones.
ANATOMICAL POSITION OF SKULL
The skull can be placed in proper orientation by considering any one of the two planes.
1 Reid's base line is a horizontal line obtained by joining the infraorbital margin to the centre of
the external acoustic meatus, i.e. auricular point.
2 The Frankfurt's horizontal plane of orientation is obtained by joining the infraorbital margin
to the upper margin of the external acoustic meatus
SKULL JOINT
The joints in the skull are mostly sutures, a few primary cartilaginous joints and three pairs of
synovial joints. Two pairs of synovial joints are present between the ossicles of middle ear. One
pair is the largest temporomandibular joint. Sutures are:
Plane - internasal suture
