University of Sydney researchers have found that it is chewing and biting that causes adult teeth to break through the gums—not an innate, unknown force.
Dr Babak Sarrafpour and his team from the faculties of Dentistry and Engineering and Information Technologies made this discovery following their development of a 3D biomechanical model that shows the stress distribution within the jaw as it bites and chews.
The researchers used CT scan images of an eight-year-old’s mandible to design the 3D model which they then used to look at the forces produced by the jaw when biting and chewing.
“We designed the hard and soft tissues in the jaw and inputted the data we had about jaw movements into the software,” Dr Sarrafpour explained.
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.
Dr Sarrafpour noted that there have been a number of longstanding hypotheses around the eruption of adult teeth but so far none have been clinically proven.
“However, 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 un-erupted adult teeth acts as a mechano-sensor in response to biting forces and remodels surrounding bone in a way that carries the tooth to the mouth.”
Dr Sarrafpour is hopeful his team’s research will lead to further preventive 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.
“At the moment, we’re 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 remodelling,” Dr Sarrafpour said.
“There is the possibility that, if that is the case, we could use a form of intraoral appliance or stress-shielding implants that could redistribute stress on certain parts of the jaw, and trigger teeth to erupt at the right angle.”