Biomedical Engineering Reference
In-Depth Information
progression, respectively. Despite these considerations and regular use of tooth brushes, most
patients do not clean their teeth as properly as necessary for caries prevention. Accordingly, addi-
tional strategies and new preparations for optimized biofilm management as well as remineraliza-
tion of incipient dental lesions are necessary. In general, a vast number of artificial materials and
related products are available for oral health care and preventive dentistry. However, they are not
as effective as desirable. Furthermore, the conventional oral health-care products represent no bio-
mimetic or at least biological approaches for biofilm management in the oral cavity. Furthermore,
since the physiological remineralization is frequently inadequate to maintain the integrity of enamel
and dentin exposed to modern diet and nutrition behaviors, the natural remineralization process
after an acidic challenge needs to be augmented. This applies not only for carious attacks but also
for dental erosion. The prevalence of erosions is increasing due to the extensive consumption of
acidic beverages in the industrialized countries
[5]
. In particular, eating disorders combined with
often high resistance to psychological therapy cause extensive erosive defects
[6]
. Accordingly,
also for dental erosion, additional strategies are required to prevent demineralization and to improve
remineralization. Thereby, the specific mode of demineralization which is different from dental car-
ies has to be considered as well as the interactions of proteolytic enzymes with the demineralized
dentin matrix
[7,8]
. Due to the interaction of acidic agents with the hierarchically nanostructured
dental hard substances, especially nanomaterials are of interest for treatment of initial erosive
lesions
[9]
.
Loss of periodontal attachment as well as gingival recession leads to the exposure of the root
surface. Wrong or excessive tooth brushing can induce abrasion and accelerated loss of the exposed
dental hard substance. This often results in tooth hypersensitivities, which are characterized by
opened dentinal tubules. Nanoscaled particles might help to obturate the open dentin tubules, which
are responsible for the hydrodynamic and osmotic effects inducing the hypersensitivities
[9,10]
.
Nanomaterials might also be of interest for preventive, therapeutic, and regenerative strategies in
periodontal disease itself, but this is not the topic of the present review.
The relevance of nanotechnology and nanobiomaterials to overcome these challenges in oral
medicine is clearly mirrored by the increasing number of papers that had been published over the
last few years describing nanotechnological approaches and nanosized materials with proposed
applications in preventive dentistry
[9,11
14]
. In principle, the effects of such nanobiomaterials
are governed by surface interactions and the process of bioadhesion at the tooth surface
[15]
.
This applies for physiological as well as pathophysiological mechanisms and processes taking place
at the tooth
saliva interface. Thereby, strategies mimicking nature at the nanolevel seem
to be the most promising approaches as they try to avoid successfully unpredictable adverse effects
potentially caused by artificial agents
[16]
. For the development and understanding of these strate-
gies, it is necessary to have a closer look on the process of bioadhesion, surface interactions, as
well as de- and remineralization occurring at the tooth to saliva interface.
biofilm
8.2
The ubiquitous phenomenon of bioadhesion on dental hard tissues
The teeth are characterized by nonshedding surfaces which are the essential fundament for the inci-
dence of caries, periodontal diseases, and dental erosion
[15]
. In this context, the bioadhesion of
