University of Manchester

Development and Application of Er:YAG Laser in Restorative Dentistry.

Abtesam Imhammed Aljdaimi

Scientific Case

Erbium lasers are recognized as the ideal dental lasers for precise, effective, and minimally invasive ablation of dental hard tissues. Dental hard tissues and bone are composed mainly of the same mineral contents with varied concentrations. Many studies have studied the effect of laser in hard tissues using different techniques including scanning electron microscope. However, to our knowledge, no study demonstrated the effect of laser on hard tissues by the nanotomography technique. Therefore, the aim of this study to see the effect of Er: YAG laser on hard tissues in three-dimensional at the nanometer scale.
Human teeth and Rat bone

Experiment Design

Sample preparation
Carious-free human permanent premolar teeth, stored in a 10% buffered formalin solution before the use under the Human Tissue Authorization of University of Manchester in the UK were selected for this experiment. Prior to sectioning, the teeth were stored in distilled water that was changed periodically, in order to remove any remnants of formalin. The teeth and rat bone samples were sectioned transversally using IsoMet┬« 1000 Precision Saw. The rat bone was also stored in 10% formalin solution. Then, the samples thickness was prepared to be 100 ┬Ám in wedge form using abrasive papers.
Laser irradiation
All the experimental sections received an Er: YAG laser treatment (Fidelis Surgical Laser Model 320A Er: YAG Fotona Medical Lasers) emitting at a wavelength of 2940 nm, with energy density of 0.062 J/ cm^(-2), pulse energy of 100 mJ and repetition rate of 10 Hz. The laser was working in very long mode (750-950 microseconds).
The samples will be scanned by the nanotomography before and after laser irradiation. The structure of each tissue will be seen in 3D to see the effect of laser.
Scanners and Rigs
Xradia Ultra XCT
Not Required

Sample & Safety

In this study, three types of samples are going to see.
(1) Human enamel.
(2) Human dentine.
(3) Rat bone.

One sample of each kind is going see two times before and after the irradiation.

Regarding the hazardous, no hazards from the sample as the specimens are already fixed with the formalin. However, to remove the effect of formalin, the samples will be put in distilled water for 24 h prior to the experiment and it will be changed periodically to remove any remnants of formalin.
Low Hazard

Scan Records

Project Report