Understanding dental anatomy and bite marks

What we are seeing is on the top is a maxillary dentition. The down part is the mandibular dentition. So identifying teeth is important. We have four types of teeth- the central what we have are the incisors. In that the first teeth is central then the lateral. Then what is projecting is the canine. Then we have two premolars and the last three are the molars. This I am referring it so easily because we are all aged over twenty years. That is why we will have all permanent teeth. Temporary teeth or what children below six years have-twenty teeth. They are temporary. They slowly move on to become permanent teeth.

So temporary is also known as the primary teeth and the deciduous teeth whereas permanent teeth are referred to as secondary teeth. So we all have permanent. They are twenty eight plus four. Those four are called the wisdom tooth. So thirty two teeth and children below the six years have only twenty teeth. From six to twelve years is when there is a mixed dentition. The temporary teeth are moving, permanent teeth are coming. So those are referred to as mixed dentition age group.

The first thing that must be appreciated is the inherent complexity in bite mark injuries. The injury itself combined with subjective nature of interpretation and the dynamic nature of the biting incident produces a number of problems which do not have ready answers available. The words here give a perfectly reasonable definition of a human bite mark on human skin. The truth, however, is far less clear cut. I have only ever once in my twenty year career seen a bite mark that fulfills all of the criteria stated here. And that is this injury here in the image on the right-curved and separate dental arches, clearly visible individual tooth marks clearly visible.

I can easily tell upper from lower teeth and have a rough idea of alignment. But even in this clear injury, there are issues with providing a factually correct match to a suspect that I will explain as we continue. The injury on the left is instructive in light of our forthcoming conversation. We can see here some of the severe distortion that is evident in almost all bite mark injuries. The injury does not represent a true reflection of the shape of the dentition, even though this injury is quite fresh. Here we can see a selection of bite marks that I’ve been asked to provide opinions for over the years.

This collection represents, more realistically, the average quality of injury we are asked to assess and comment on. All these injuries have issues that make meaningful comparisons impossible.