Customer : Sebastian Aguayo, Pontificia Universidad Catolica de Chine, Santiago, Chile
Highlighted publication: Ultrastructural characterisation of young and aged dental enamel by atomic force microscopy Sebastian Aguagyo et al (2022) Journal of Microscopy – Special Issue 288 (3)
Instrument: Asylum MFP 3D-SA AFM
Probes: SCOUT 350 RAu
Imaging modes: Intermittent Contact (AC mode)
Keywords: Dental Industry, AFM, Atomic Force Microscopy, AFM Probes, Microscopy, Dental Enamel, Characterisation
Dental enamel is the hardest substance in the body. It forms a protective surface on teeth, to help with the wear and tear that comes from eating and drinking a variety of food and beverages. However, from the age of 50 years onwards enamel thickness is known to steadily decrease. This makes teeth vulnerable to damage and decay, potentially resulting in tooth loss and affecting the health and eating habits of older people.
Prior to research conducted by the team at Pontificia Universidad Catolica de Chine, changes in enamel structure due to ageing had not previously been explored with nanoscale resolution.
Enamel is predominantly formed by a mineral phase of hydroxyapatite (HA) – composed of calcium and phosphate ions. HA crystals form compact enamel rods from the interior to the outer surface of the tooth enamel.
The purpose of Aguagyo et al’s study was to begin to explore whether high-resolution AFM could provide more detailed information on the effects of ageing on tooth enamel structure. Understanding potential changes in enamel ultrastructures could aid in the development of novel therapeutic dentistry approaches for the elderly.
Using NuNano’s silicon AFM probes (Scout 350 RAu) with an Asylum Research MFP 3D-SA AFM the team were able to examine specimens of tooth enamel from a sample of six teeth, across a range of ages. They characterized the samples, recording height, amplitude and phase channels, in intermittent contact (AC mode) under environmental conditions.
Specifically, the team were interested in the extent to which high-resolution AFM could help them determine potential differences in topography, HA crystal size and surface roughness at the nanoscale.
Sectioned enamel specimens were cleaned and samples were mounted onto metal discs. Using a free amplitude of 1V and adjusting the imaging setpoint during scanning for image optimisation, the nanoscale images were produced for the internal and external enamel regions (Fig 1A).
Conclusions
Important variations in HA crystal width and roughness across the analysed specimens were identified. In particular, increased surface roughness and decreased HA width was seen in the older external enamel group compared to the younger one.
The study demonstrated that high-resolution AFM was an effective approach for the qualitative and quantitative characterisation of human dental enamel ultrastructure. Given the study’s initial results, this approach could offer a valuable new way to explore ageing in dental enamel, with future work recommended to focused on assessing larger sample sizes.