Anatomy – Permanent Dentition

 

 

Anatomy – The Permanent Dentition

Human teeth are divided into two groups whose development is genetically regulated.  From between the age of 6 months and 12 years primary teeth are present in the mouth and are shed as the permanent teeth erupt.  Developmentally the permanent dentition commences mineralisation (calcification) at or just before birth.  Mineralisation of teeth continues until, on average, 19.82 years. The earliest time of mineralisation at or around birth is an important forensic indicator for the age estimation of neonatal infants that have died. [see Whittaker DK and MacDonald DG. A Colour Atlas of Forensic Dentistry. Pages 60,61. Wolfe Publishing Ltd. London 1989.  ISBN 0-7234-0961-7 ]

For most dental age estimates, the Reference Data Set (RDS) is based on Dental Panoramic Tomographs (DPTs) which range between 3.0 and 25.0 years. (There are DPTs from older patients but these are above the age threshold of interest to the DARLInG  group).

[ See Clark DH  Practical Forensic Odontology. 1992, Wright. Oxford. ISBN 0-7236-1511-X. Chapter 3. ]

For Dental Age Estimation purposes, only the teeth on the Left side are used.  This is because there is almost perfect Right – Left Symmetry in Tooth Development. Statistically there is no advantage in using contralateral teeth as the data from each side would need to be combined.

 
This bilateral symmetry has the advantage that if a tooth is lost as a result of trauma or is developmentally absent, the contralateral tooth can be substituted.

Skull of a young adult approximately 19 years old.  This shows the complete permanent dentition of 28 teeth (32 teeth if third molars are present).

OLYMPUS DIGITAL CAMERA

 

Anterior view of dental region if the above skull.  It shows a close view of the anterior teeth on the LEFT side. The Upper Right Permanent Central Incisor [ BrDJ UR1 ]  [ FDI 11 ] is damaged.  The front part of the tooth has sheared off.  It reveals the extent of the pulp cavity (nerve cavity) within the crown of the tooth,

OLYMPUS DIGITAL CAMERA

Occlusal view of the Maxillary (Upper Arch) of the complete Permanent Dentition.
The teeth on the left side are labelled using the British Dental Journal Notation
and the FDI notation.    [ see Tooth Nomenclature ]

 

OLYMPUS DIGITAL CAMERA

 

Occlusal view of the Mandibular (Lower Arch) of the complete Permanent Dentition.
The teeth on the Left side  are labelled using the British Dental Journal Notation and the FDI notation

OLYMPUS DIGITAL CAMERA
[ see Tooth Nomenclature ]

The teeth almost always used in DAE are the developing permanent teeth on the LEFT side. [ see Dental Age Estimation – The Procedure ]

~~~~~~~~~~~~~~~~~~~~ END ~~~~~~~~~~~~~~~~~~~