Medical and Dental Biofilms

Image 1. Medical Dental biofilms.

Biofilm growth on human tissue, dental surfaces, and prosthetic implants is a rapidly growing concern to the medical industry. Oral biofilms promote tooth decay (dental caries) and gum disease. Biofilms may develop on catheter surfaces as well as the surfaces of prosthetic implants resulting in infection. Note that bacterial cells which detach from these biofilms can enter the circulatory system an be transported through the human body.'

Image 2. Elbow prosthesis.

Here is an Scanning Electron Micrograph of showing biofilm growing on an elbow prosthesis removed from a patient.

The foregoing examples illustrate that practitioners in diverse industrial sectors have very similar concerns about biofilm accumulation and activity in their respective systems including how to detect and quantify biofilm accumulation, how to identify the presence of key bacterial strains, and most importantly, how to control biofilm accumulation. It should be noted that the existing and evolving method for biofilm detection, quantification and identification usually (with some exceptions) require some form of laboratory analysis to complete. These methods are covered in detail in Module 8 “Methods for Studying Biofilms” . One obvious opportunity in the biotechnology arena there is to develop such methods in a format with can be applied directly in the field.

As we see again the same type of biofilm research questions are of concern to the medical industry namely: How to detect, quantify, identify and control bacterial cells on medical dental surfaces? What is the significance of biofilms to periodontal disease, dental caries, prosthetic implants and chronic wound care?

Image 3. Biofilm Control

The biofilm control concepts of destruction, prevention, and removal are illustrated in this slide. Some of the more interesting research-oriented concepts are based on understanding and controlling the production of signaling molecules within the biofilm—thereby possibly blocking the production of EPS (and preventing biofilm formation) or causing the biofilm to detach and be easily removed from the system. There is also considerable research being done on engineering “fouling resistant” surfaces which prevent or reduced initial attachment of cells. The more traditional methods of controlling biofilm are mechanical scraping or other form of physical removal along with killing biofilm cells with biocides or antibiotics. However, as the next series of slides shows, biofilm cells can be very resistant to biocidal attack. Detailed coverage of the topic of biofilm control is found in Module 5 “Control of Biofilm Accumulation”