Age at death estimation has several indicators that can be used to quantify an age range for the individual being studied. However, it is always best to examine as many features as possible in order to obtain the most accurate estimation.
The pubic symphysis is the most anterior point of the pelvis where the two pubis bones articulate together. The wear on the articular surfaces of the pubis bones is an accurate assessment of age at death. As a young adult this surface has a billowed appearance with ridges running in the transverse plane. As the individual becomes older these ridges erode and surface becomes grainy. After complete erosion, the surface becomes depressed creating a raised rim around the articular surface. At this stage, pitting is often observable. In the oldest individuals, the rim has also been eroded away, deepening the articular surface.
Cranial sutures are also accurate measures of age at death. Sutures undergo continuous obliteration after an individual has finished growing and the degree to which different sutures are closed can give good estimates. Although there are multiple sutures in the cranium, the focus here will be the coronal, the sagittal, and the lambdoidal sutures. Each suture is ranked in a four-point system, with each category corresponding to a different level of closure:
- Level 0: open
- Level 1: minimal closure
- Level 2: significant closure
- Level 3: complete obliteration
After each suture has been ranked accordingly, the scores are added to create a composite score. The composite score give an age range for the individual under examination.
One of the most accurate ways to age an individual is by their dental eruption and attrition. In depth studies of tooth eruption have enabled forensic scientists and osteologists to assign ages based on the presences and absences of different teeth. This is an important aspect of age determination of juveniles. A good example of this is the third molar or more commonly known as the wisdom teeth. Third molar eruption usually takes places between ages 16-24. Therefore, if an individual with molars in the process of erupting is found, this age range can be accurately applied.
However, the third molar is a unique case, because unlike any other tooth, it is more often congenitally absent. The absences of third molars should not be used as an automatic indicator of adolescence because there are many adults do not have their third molars. This finding is even more pronounced in modern industrial populations since many individuals elect to have their third molars removed through dental surgery when there are problems of overcrowding and impaction.
Dental attrition, or wear, is also provided reliable age ranges. Chewing involves the grinding of food against occlusal surfaces and this also has the side effect of grinding teeth down as well. There are three categories of wear that can be assigned to overall dental attrition.
- Category A has minimal wear on all teeth except the third molars, which exhibit no wear.
- Category B has intermediate wear on all the teeth except the second and third molars, which exhibit minimal wear.
- Category C has severe wear on all the teeth except for the third molars, which have intermediate wear. The fact that the third molars, and sometime the second molars, do not have the same wear pattern as the rest of the dentition can be attributed to the later eruption of these teeth.