Investigation of impact of sugary and acidic foods on modifying acquired salivary pellicle and dental erosion

Dental erosion involves the loss of the hard tooth substances due to acidic sources from food and drink (extrinsic) and stomach acid (intrinsic) and has become a prevalent oral health problem which can lead to many clinical concerns such as poor appearance, loss of function, pain and discomfort. The protective roles of proteins and minerals in saliva and acquired enamel pellicle against dental erosion have been well documented. The thickness and lubrication performance of the acquired enamel pellicle is influenced by a number of chemical, biological and behavioural factors including the role of whole mouth saliva, as well as the severity of, and duration of exposure to, acidic food and drinks.

The sugars in drinks can also play a synergistic role in dental erosion. The modification of both saliva and acquired enamel pellicle as well as the true erosive potential of sugary and acidic drinks remains poorly understood. The type, concentration and interplay of sugar-acid on changing the thickness and lubricity of whole mouth saliva and acquired enamel pellicle are yet to be studied. Therefore, a better understanding of the salivary protein interactions in whole mouth saliva as well as acquired enamel pellicle when exposed to sugar-acid food environment are of paramount importance in understanding the mechanism of dental erosion progression.

This PhD project led by Dr. Mahdi Mutahar at University of Portsmouth Dental Academy in collaboration with the Colloids and Oral Tribology laboratory of Prof. Anwesha Sarkar at University of Leeds will address this knowledge gap using a novel suite of in vivo and in vitro experimental approaches. A range of biochemical techniques, optical methods, tribology measurements and quartz crystal microbalance with dissipation monitoring will be employed.

Dental erosion happens when the hard surface of a tooth wears away due to acids from our diet (like certain foods and drinks) or from stomach acid. This is a growing problem and can lead to visible wear on teeth, loss of function, pain, and general discomfort. Thankfully, the proteins and minerals in saliva, along with a natural protective coating on our teeth called the "acquired enamel pellicle," help guard against this erosion.

However, this protective enamel pellicle layer varies in thickness and how well it works, influenced by what we eat and drink, how acidic these items are, and how often and for how long we consume them. Sugars in drinks can also worsen erosion, but we still don't fully understand how sugar and acid work together to affect saliva and the enamel pellicle.

This PhD project, led by Dr. Mahdi Mutahar at the University of Portsmouth Dental Academy and in partnership with Professor Anwesha Sarkar's team at the University of Leeds, aims to shed light on these questions. Using innovative laboratory and live testing methods, they will explore how sugar and acid in foods interact with saliva and enamel pellicle, examining factors like pellicle thickness, salivary proteins, and how well the pellicle layer protects against erosion. This research will provide new insights into dental erosion and how we might better protect our teeth against it.