The document discusses the bones that make up the human skull. It is divided into two parts: the axial skeleton and appendicular skeleton. The axial skeleton includes the skull bones, which are divided into the cranium and mandible. The cranium contains eight bones, while the mandible is a single bone. The document further describes several important skull bones in more detail, including the maxilla, mandible, nasal bones, ethmoid bone, and sphenoid bone. It outlines the structures and features of each bone.

1. Bones of the Jaw
Dr. Yumna
Lecturer
Dental Hygiene and Technology

2. Human Skull

3. Human Skull
• Human skull is divided into 2 parts
– Axial skeleton
– Appendicular skeleton

4. Axial Skeleton
• Consists of the bones of the head and trunk of a
vertebrate
• It consists of 80 bones and is composed of six parts
– The skull bones
– The ossicles of the middle ear
– The hyoid bone
– The rib cage and sternum
– The vertebral column

5. Axial Skeleton

6. Appendicular Skeleton
• The appendicular skeleton is divided into:
– Pectoral/Shoulder Girdle
• Clavicles
• Scapulae

7. Appendicular Skeleton
– Pelvic Girdle
• Hip bone
• Sacrum
• Coccyx

8. Appendicular Skeleton
• Fore limbs
• Hind limbs

10. Skull

11. Human Skull
• The skull is a bony structure that forms
the head in vertebrates
• It supports the structures of the face and provides a
protective cavity for the brain
• The skull is composed of two parts:
– The cranium
– The mandible

12. Bones of Skull
• One Occipital bone
• Two temporal bones
• Two parietal bones
• The sphenoid,
• Ethmoid and
• Frontal bones.

13. Bones of Skull

14. Bones of Skull
• The bones of the facial skeleton(14) are
– The vomer
– Two nasal conchae, two nasal bones
– Two maxilla
– The mandible
– Two palatine bones
– Two zygomatic bones and
– Two lacrimal bones.

15. Bones of Skull

16. Nasal Bones

17. The Maxilla
• Also known as the upper jaw
• Maxilla is the second largest bone of the face, first
being the mandible
• The two maxillae form the whole of the upper jaw
• Plays an important role for mastication and
communication.

18. The Maxilla
• It contributes to the formation of:
– Floor of the nose and orbit
– Roof of the mouth
– Lateral wall of the nose
– Pterigopalatine and infratemporal fossae
– Pterigomaxillary and infraorbital fissure

19. The Maxilla

20. The Maxilla
• The maxillary sinus is one of the four
paranasal sinuses, which are sinuses located
near the nose.
• The maxillary sinus is the largest of the
paranasal sinuses
• Maxillary sinuses are located below the
cheeks, above the teeth and on the sides of the
nose

21. The Maxilla

22. The Mandible
• Also known as the lower jaw
• Largest bone of the face
• It forms the lower jaw and holds the lower teeth
in place.
• The mandible is the only movable bone of the
skull

23. The Mandible
• The body of the mandible is curved somewhat
like a horseshoe and has two surfaces and two
borders.
• A broad quadrilateral part of the
mandible projecting upward from the posterior
end of the body behind the lower teeth is called
ramus

24. The Mandible

25. The Mandible
• It has:
– Mylohyoid ridge
– Coronoid process
– Condylar process
– Mndibular foraman
– Mental foraman
– Angle
– Body
– Ramus

26. The Mandible
• The external surface of
the mandible is marked in
the median line, indicating
the mandibular symphysis,
or symphysis menti
• junction where the two
lateral halves of
the mandible fused at an
early period of life.

27. The Mandible
• Parasymphysis region is present below the canines

28. The Mandible
• Inferior alveolar nerve enters in mandible from
mandibular foraman

29. The Mandible
• It transmits the
terminal branches of
the inferior alveolar
nerve and vessels
(the mental nerve
and artery).

30. Temporomandibular Joint (TMJ)
• A joint where mandibular condyle articulates with
the glenoid fossa of temporal bone.

31. Ethmoid Bone
• An unpaired bone in the skull that separates the
nasal cavity from the brain
• It is located at the roof of the nose, between the
two orbits
• Anterior cranial bone located between the eyes
• It contributes to the medial wall of the orbit, the
nasal cavity, and the nasal septum

32. Ethmoid Bone

33. Ethmoid Bone

34. • An unpaired bone of the neurocranium
• It is situated in the middle of the skull towards
the front, in front of the temporal bone and
the basilar part of the occipital bone
• Its shape somewhat resembles that of
a butterfly or bat with its wings extended.
Sphenoid Bone

35. Sphenoid Bone

36. Sphenoid Bone

37. Skull Bones