Sutures of the neurocranium join the frontal, sphenoid, temporal, ethmoid, parietal, and occipital bones. They are found on the superior, posterior, lateral, and inferior parts of the skull. Some sutures also run along the midline. However, most are located on both sides of the skull and are paired.

The sutures of the neurocranium include the following fibrous joints:

Metopic (frontal) suture - a vertical midline suture that separates both frontal bones at birth; this suture is present in children; together with the coronal and sagittal sutures, it contributes to the formation of the anterior (frontal) fontanelle; typically, it runs from the anterior fontanelle/bregma to the nasion, but it can also be incomplete; the metopic suture fuses between the ages of 3 to 8 months; in most people, the metopic suture has ossified by the age of 9 months; some adults may have remnants of metopic sutures known as persistent metopic sutures that are anatomical variants and can be easily misdiagnosed as skull fractures;
Frontoethmoidal suture (2) - a relatively short paired suture that separates the frontal and ethmoid bones; it is found on the medial wall of the orbit; this suture marks the articulation between the orbital plate of the frontal bone and the orbital plate of the ethmoid bone; closure of this suture happens between the 50 and 60 years of age;
Sphenofrontal (frontosphenoidal) suture (2) - this suture marks the separation between the greater wing of the sphenoid and the frontal bone; it is seen on the lateral wall of the orbit and on the anterior aspect of the lateral side of the skull; it can be described as the inferomedial extension of the coronal suture; the ossification of this suture is usually completed around 12 - 15 years of age (can happen anytime between age 5 and 15);
Coronal suture (2) - a paired suture that is seen on both lateral sides and the superior aspect of the skull; it is also called the frontoparietal suture, as it is formed at the junction between the parietal and frontal bones; it runs horizontally and obliquely across the anterosuperior aspect of the skull; in the middle of the skull, it intersects with the opposite coronal suture and the metopic (in children) and sagittal sutures; the ossification of the coronal suture finishes at around 24 years of age; in children, both coronal sutures are separated by the anterior (frontal) fontanelle, while in adults both coronal sutures have fused; the name of the suture derives from Latin “corona” and Ancient Greek “korone,” both translating to “crown” and referring to the anatomical location where the crown is usually placed;
Sphenoparietal suture (2) - a short, paired suture that is located between the greater wing of the sphenoid and the sphenoidal angle of the parietal bone; it contributes to the formation of cranial landmark known as the pterion; it is found laterally to the sphenofrontal suture; the closure of this suture starts around 2 years of age and is completed by the age of 6 - 7 years;
Sphenosquamous (sphenosquamosal) suture (2) - a paired, oblique suture between the squamous part of the temporal bone and the greater wing of the sphenoid; it is found on both lateral sides of the skull below the sphenofrontal suture; like the previous suture, it also contributes to the formation of the pterion; it usually has ossified at around age 10;
Squamous (squamosal) suture (2) - a serrated and oblique paired suture that is seen on the lateral side of the skull; it is formed by the squamosal border of the parietal bone and the squamous part of the temporal bone; anteriorly, the squamous suture contributes to the formation of the pterion; this suture typically ossifies later in life and sometimes it is not completely closed until 60 years of age;
Parietomastoid suture (2) - a direct posterior continuation of the squamous suture; it is found at the posterior end of the squamous suture and is formed between the parietal bone and the mastoid part of the temporal bone;
Squamomastoid suture (2) - an occasionally present paired suture between the squamous and mastoid parts of the temporal bone; sometimes, it forms a ridge;
Occipitomastoid suture (2) - an oblique inferior continuation of the lambdoid suture; it is formed between the squamous part of the occipital bone and the mastoid part of the temporal bone; it participates in forming cranial landmark known as the asterion; this suture has completely closed at around 16 years of age;
Lambdoid (lambdoidal) suture - an inverted U-shaped suture that is found on the posterior aspect of the skull; it is formed between the lambdoidal border of the occipital bone and the occipital borders of both parietal bones; this suture is also known as the parietooccipital suture; it participates in forming cranial landmark called the lambda; this suture usually has ossified between 20 - 30 years of age (on average, 26 years of age);
Sagittal (interparietal) suture - it runs across the midline of the calvaria; formed between the sagittal borders of both parietal bones; posteriorly, it meets the lambdoid suture and contributes to the formation of the lambda; anteriorly, it meets the coronal suture and contributes to the formation of the bregma; ossification of this suture usually happens around 22 years of age but can also occur much later;
Mendosal suture - it is an accessory suture that is present occasionally on the occipital bone; it is a normal anatomical variant of cranial sutures; this suture extends throughout the occipital bone; the occipital bone develops from six different ossification centers - the Mendosal suture develops due to incomplete or improper fusion of occipital and nuchal planes; it may be easily confused with fractures; these sutures most commonly are bilateral and symmetrical;
Sphenoethmoidal suture - a short suture that is found in the anterior cranial fossa; it is formed between the sphenoid and the ethmoid.

Note: Some authors name the sphenoccipital, sphenopetrosal, petrooccipital, posterior intraoccipital, anterior intraoccipital, and sphenoethmoidal synchondroses as sutures. However, this is incorrect, as synchondroses are completely different joint types. Synchondroses are primary cartilaginous. Within these joints, the adjacent bones are joined by hyaline cartilages. Also, this joint type includes sites where a bone is united only to hyaline cartilage. Some authors also mislabel petrotympanic, petrosquamous, tympanosquamous, and tympanomastoid fissures as sutures.

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Sutures of neurocranium