The Problem - Tooth Decay

Poor oral hygiene combined with frequent ingestion of simple sugars creates an environment in which changes in the oral microbiome (dental plaque) can cause dental caries (tooth decay). If tooth decay is left untreated it causes the breakdown of teeth, with symptoms that include pain, difficulty eating and tooth loss. While education, water fluoridation and improvements to oral hygiene products have helped to decrease caries incidence and severity, the prevalence of the disease remains remarkably high ~90% of adults and ~60% of adolescents in the US have experienced caries in their adult teeth. In addition, approximately 40% of children have had dental caries in their teeth. Surgical restoration remains a primary way to treat caries, with significant costs associated with dental treatment. Moreover, caries is predicted to remain a significant global health problem as developing countries increase consumption of cariogenic sugars and life expectancies increase.

Below is a simple diagram explaining the process of caries which is predominately caused by shifts in the abundance of certain oral bacteria. These shifts are caused by changes in the environment - eating and drinking excess sugar without good oral hygiene.

Our Approach

The long-term goal of the lab is to understand how Streptococcus mutans causes tooth decay. This includes addressing which genes are essential for pathogenesis, and what is the role of other bacteria in promoting or reducing S. mutans colonization. Systems and synthetic biology techniques are critical tools for addressing these problems. Our projects occur at three levels, that we call the information, discovery, and molecular stages. We gather the ‘information’ by forward genetic screens, and then we validate interesting findings at the ‘discovery’ stage. Exceptional findings then move towards mechanistic studies at the ‘molecular’ stage. Ultimately, understanding the biology of this organism will allow us to develop new treatment modalities, both against S. mutans and other streptococcal pathogens. We have several collaborations with chemists who are actively exploring antimicrobials both against S. mutans and other patogens.

The Tools

We use a variety of methods, both traditional and modern, to understand how Streptococcus mutans causes tooth decay. These tools include, next generation sequencing, electron microscopy, forward genetics (transposon sequencing), CRISPR technologies and fluorescence microscopy. Just like everyone else, we also want to apply artifical intelligence approaches to super charge our research.