Biting and chewing forces tooth growth
University of Sydney researchers have found chewing and biting to be the cause of adult teeth breaking through the gums rather than an innate, unknown force.
and his team of researchers from the faculties of Dentistry and Engineering and Information Technologies developed a 3D biomechanical model that shows the stress distribution within the jaw as it bites and chews.
Dr Sarrafpour says that his multidisciplinary team used CT scan images of an eight year old鈥檚 mandible to design a 3D model they could then use to look at the forces produced by the jaw when biting and chewing.
鈥淲e designed the hard and soft tissues in the jaw and input the data we had about jaw movements into the software. We simulated both the back teeth and front teeth chewing and we could assess the stress on the teeth, bone and soft tissue,鈥� he says.
It was found that the chewing and biting actions of the jaw deform the thin layer of soft tissue surrounding the teeth that are yet to appear, forcing them outwards.
3D model of a jaw
Dr Sarrafpour says the team developed the theory after a number of long-standing hypotheses were unsupported by clinical evidence.
鈥淭here were a number of hypotheses surrounding how adult teeth erupted. Perhaps it was from the root forming and pushing the tooth towards oral cavity, maybe it was the blood pressure in dental pulp or perhaps it was the periodontal ligaments forming and contracting, pushing against the tooth.
鈥淗owever there were a number of studies that showed even if you disconnected the root and the ligaments from the tooth, it would still erupt through the bone. So we developed the theory that perhaps soft tissue dental follicle around unerupted adult teeth acts as a mechanosensor in response to biting forces and remodels surrounding bone in a way that carries the tooth to the mouth.鈥�
It鈥檚 believed this research could perhaps lead to further preventative treatments that could correct the angle of a tooth before it erupts rather than rely on orthodontic bands or braces to realign the tooth later in life.
鈥淎t the moment we鈥檙e conducting an In Vitro study to look at dental follicular cells response to compressive and tensile forces and to see their potential role in bone remodeling.
鈥淭here is the possibility that, if that is the case, we could use a form of intraoral appliance or stress shielding 聽implants that could redistribute stress on certain parts of the jaw, and trigger teeth to erupt at the right angle.,鈥� Dr Sarrafpour says.
The research project was completed by a multidisciplinary team including:
- : Discipline of Oral Pathology, Faculty of Dentistry
- : Biomaterials Science Unit, Faculty of Dentistry
- : School of Aerospace, Mechanical and Mechatronic Engineering, Faculty of Engineering