Cranial sutures connect the bones of the skull and allow flexibility during birth but become rigid in adults. There are several types of sutures located in different areas of the skull. Sutures close according to age-related timelines starting with fontanelles closing in infants and ending with some sutures closing in older adults. Three scoring systems are used to estimate age from cranial suture closure: Acsadi and Nemeskeri, Masset, and Meindl and Lovejoy. Each system assigns a score from 0-4 to describe the degree of suture closure.

2. SKULL SUTURES
FORENSIC SIGNIFICANCE
Made by: Dr. Pankti Patel
M.Sc. Forensic Odontology
Volunteer at AFRS

3. CONTENTS
• What are cranial sutures
• Types of cranial sutures
• Cranial suture closure
• Age estimation from cranial suture

4. CRANIAL SUTURES
• Cranial sutures are fibrous type of connective tissue
that connect the bones of the skull.
• The dense fibrous tissue that connects the sutures
is made mostly out of collagen. These joints are
fixed, immovable, and they have no cavity. They are
also referred to as the synarthroses.
• In fetal skull the sutures are wide and allow slight
movement during birth, but later they become rigid
and fixed just like in the adults.

5. • An infant's skull is made up of 6 separate cranial (skull)
bones:
• Frontal bone
• Occipital bone
• Two parietal bones
• Two temporal bones
• The spaces between the bones that remain open in babies
and young children are called fontanelles. Sometimes, they
are called soft spots. These spaces are a part of normal
development.
• They then grow together as part of normal growth. They stay
connected throughout adulthood.

6. • Two fontanelles usually are present on a newborn's skull:
• On the top of the middle head, just forward of center (anterior
fontanelle)
• In the back of the middle of the head (posterior fontanelle)
• The sutures and fontanelles are needed for the infant's brain growth
and development. During childbirth, the flexibility of the sutures
allows the bones to overlap so the baby's head can pass through
the birth canal without pressing on and damaging their brain.

7. Types of cranial sutures
Anterior aspect of skull:
• Frontonasal suture - between the frontal bone and
nasal bones
• Frontozygomatic suture - between the frontal bone
and zygomatic bone
• Zygomaticomaxillary suture - between zygoma and
the maxilla
• Intermaxillary suture - between two maxilla
• Metopic suture - found in children; on the midline
of the frontal bone

8. Posterior aspect of skull:
• Sagittal suture - between two parietal bones
• Lambdoid suture - between the parietal bone
and occipital bone
Superior aspect of skull:
• Coronal suture - between the frontal bone and
the parietal bone

9. Lateral aspect of skull:
• Squamous suture - between the parietal bone and
temporal bone
• Sphenofrontal suture - between the frontal bone and
sphenoid bone
• Sphenoparietal suture - between the sphenoid bone
and parietal bone
• Occipitomastoid suture - between the occipital bone
and mastoid process of the temporal bone
• Temporozygomatic suture - between the temporal
bone and zygomatic bone

10. Inferior aspect of skull:
• Median palatine suture - between the hotizontal plates of the
palatines
• Transverse palatine suture - between the palatine process of
the maxillary bone and the palatine bone
• Petro-occipital suture - between the occipital bone and
petrous part of the temporal bone
• Spheno-occipital suture - between the sphenoid bone and
occipital bone
• Petrosquamous suture - between the petrous and squamous
parts of the temporal bone
• Petrotympanic suture - between the temporomandibular joint
and the tympanic cavity

11. Image source- https://commons.wikimedia.org/

12. Cranial suture closure
SUTURE AGE OF CLOSURE
Posterior fontanelle At birth- 6 months
Anterior fontanelle 1 ½ - 2 years
Two halves of mandible 1-2 years
Metopic suture 1 year (May remain
unfused)
Basiocciput and
basisphenoid
18- 20 years (Females)
20-22 years (Males)
Lambdoid 45-50 years
Sagittal 50-60 years
Coronal 50-60 years
Parieto-mastoid 55-70 years
Parieto-temporal 60-70 years

13. Age estimation from cranial suture
• Acsadi and Nemeskeri scoring system
SCORE DESCRIPTION
0 Open suture. Little space left between edges and
adjoining bones
1 Incipient closure. Suture is closed but clearly visible
as a continuous zigzag line
2 Closure in process. Suture line thinner, less zigzag
may be interrupted by complete closure
3 Advanced closure. Only pits indicate where the
suture is located
4 Closed suture. Suture completely obliterated

14. • Masset scoring criteria:
(1)Open, with no evidence of bony bridging across the
suture.
(2)Minimal closure, indicated by any evidence of bony
bridging up to 50% closure.
(3)Significant closure, indicated by evidence of bony
bridging of greater than 50%.
(4)Obliteration, with no trace remaining of the suture
margins

15. Image source- sciencedirect.com

16. • Meindl and Lovejoy scoring system
SCORE DESCIPTION
0 Open.There is no evidence of any ectocranial closure at
the site
1 Minimal closure. Given for minimal to moderate
closure-from single bony bridge across the suture to
about 50% synostosis at the site
2 Significant closure. Marked degree of closure but some
portion of the site still not completely fused
3 Advanced closure. Only pits indicate where the suture is
located