Revealing the unknowns [Part III Question 5]

Question 5 

Match the photos of the victims’ pieces of evidence, explaining your rationale for doing so. 

A short recap of our progression which includes the evidence we have collected up to this moment are:

1. An adult's skull and jaw
2. Pieces of jaw 
3. A child's jaw

Possible victims of the murder case:

1. Herman Hartono
2. Adi Hartono (son of Herman Hartono) 
3. Anya Suriati (9-year old, missing since 4 months ago)

From the first picture above, if you observe close enough you are able to see 8 dental alveolus in each quadrant of the mandibular arch; thus, we detecteeths can assure you that this skull and jaw belong to an adult. What is the rationale behind our interpretation? This is because there are 7-8 teeth in each quadrant of a permanent dentition whereas there are only 5 teeth in each quadrant of a primary dentition . The pictures below show both permanent (adult) dentition and primary (child) dentition. 

PRIMARY DENTITION

PERMANENT DENTITION

Besides that, the dentition also clearly shows a third molar at quadrant 4, which further indicated that the skull and jaw do not belong to Anya Suriati as she is a 9-year old girl. Up to this part, we can safely assume that the skull and jaw from picture 1 can either belong to the once living Herman Hartono or his son.

Moving on to the second group of pictures, we detecteeths can deduce that they are different views of the lower right jaw bearing first, second and third molars according to the position of mandibular foramen. Besides that, all the teeth show characteristic of permanent molars, especially the third molar where it is the smallest molar among all three. As explained above, since there is a third molar, this piece of jaw could also belong to either the father or the son. 

Now that we have interpreted the first 2 pictures, we can make a conclusion that the jaw shown in the third picture belongs to Anya. From our observation, the jaw bears a primary mandibular canine with a sharp cusp tip and the mesial slope is shorter than the distal slope. By comparing this jaw to the previous ones, it is relatively smaller, hence further proves our finding.

Here we would also like to enlighten you on some facts about the rate of decomposition of human bodies as we can clearly observe that the child jaw was rather decomposed. From a forensic pathologist point of view, decomposition which can also be known as putrefaction is the final stage following death, which is mainly caused by the action of bacterial enzymes. There are certain conditions that can affect the rate of decomposition:

• Moisture can speed up the rate of putrefaction, rapid drying of body is able to inhibit the process of decomposition.
• If the surface of the body is injured, decomposition tends to take place more rapidly. This is because if there is any presence of wound or other forms of violence before death, decomposition becomes easier for microorganism to gain access to the damaged tissues. 
• Body of children putrefy faster than those of older people.
• Tight clothing such as under the belt, socks or tight-fitting undergarments slows down the process as it causes compression of tissues and prevents access of airborne organisms, flies or insects which can destroy the tissues.
• Acidic soil and high soil moisture content will hasten the rate of decomposition of buried bodies.
• Bones exposed to the air and sunlight blanch more quickly, they can also take on the colour of the material which they are buried. 
• If the bones are found to have a splotchy brown discolouration and greasy texture, it means that there is fats present in the bones and that the bones are from a recent death that occured months, not years ago.

So...my budding detecteeths, what do you have in your mind now? ;)

References:
1. http://www.forensicpathologyonline.com/e-book/post-mortem-changes/putrefaction
2. The Use of Forensic Anthropology by Robert B. Pickering and David Bachman