About 80% of US adults have some form of dental disease. There are a variety of new dental products available, ranging from implants to oral hygiene products that rely on nanoscale properties. Here, the application of AFM (Atomic Force Microscopy) and optical interferometry to a range of dentistry issues, including characterization of dental enamel, oral bacteria, biofilms and the role of surface proteins in biochemical and nanomechanical properties of bacterial adhesins, is reviewed. We also include studies of new products blocking dentine tubules to alleviate hypersensitivity; antimicrobial effects of mouthwash and characterizing nanoparticle coated dental implants. An outlook on future “nanodentistry” developments such as saliva exosomes based diagnostics, designing biocompatible, antimicrobial dental implants and personalized dental healthcare is presented.

Drebrin A, an actin-binding protein, is a key regulatory element in synaptic plasticity of neuronal dendrites. Understanding how drebrin binds and remodels F-actin is important for a functional analysis of their interactions. Conventionally, molecular models for protein-protein interactions use binding parameters derived from bulk solution measurements with limited spatial resolution, and the inherent assumption of homogeneous binding sites. In the case of actin filaments, their structural and dynamic states-as well as local changes in those states-may influence their binding parameters and interaction cooperativity. Here, we probed the structural remodeling of single actin filaments and the binding cooperativity of DrebrinA(1-300) -F-actin using AFM imaging. We show direct evidence of DrebrinA(1-300)-induced cooperative changes in the helical structure of F-actin and observe the binding cooperativity of drebrin to F-actin with nanometer resolution. The data confirm at the in vitro molecular level that variations in the F-actin helical structure can be modulated by cooperative binding of actin-binding proteins.

Cleaved, cation-derivatized Muscovite mica is utilized extensively in AFM imaging due to its flatness over large areas (millimeter cleavage planes with local RMS roughness <0.3 nm), ease of preparation and ability to adsorb charged biomolecules such as DNA1–3. In particular, NiCl2 treatment has become a common method for controlling DNA adsorption on mica substrates while retaining the mica’s ultra flat surface4. While several studies have modeled the mica:metal-ion:DNA system using macroscopic colloidal theory (DLVO, etc) 4–8, Ni-mica’s physicochemical properties have not been well characterized on the nanoscale. Efforts to manipulate and engineer DNA nanostructures would benefit greatly from a better understanding of the surface chemistry of Ni:mica. Here we present in-situ, nanometer- and attogram-scale measurements, and thermodynamic simulation results that show the surface chemistry of nickel treated mica is more complex than generally appreciated by AFM practitioners, due to metal ion speciation effects present at neutral pH. We also show that under certain preparations, Ni:Mica allows in situ, nanoscopic nucleotide sequence mapping within individual surface-adsorbed DNA molecules by permitting localized, controlled desorption of the double helix by soluble DNA binding enzymes. These results should aid efforts to precisely control DNA:mica binding affinity, particularly at physiological pH ranges required by enzymatic biochemistry (pH 7.0–8.5)4–8, and facilitate development of more complex and useful biochemical manipulations of adsorbed DNA, such as single molecule sequencing.