It is concluded that LLLT does improve bone healing, and this can be safely assessed by Raman spectroscopy.

No abstract

An algorithm using PCA and discriminant analysis based on m-distance has been developed and successfully applied to diagnose coronary artery disease by NIRS obtaining good sensitivity and specificity for each tissue category.

Utilization of optical-fiber catheters can turn the Raman spectroscopy system into a powerful remote biomedical diagnostic probe. An in vivo (a qualitative and a quantitative) biochemical diagnosis of biotissues is possible by developing the Raman-fiber probes with a good flexibility and less background signals generated in the probes themselves. Considering the isotropic nature of Raman scattering, the amount of Raman signal guided through the fiber is expected to depend on the numerical aperture (NA) of the fiber. To study the dependence for catheter probes experimentally, various flexible probes (with small diameter fibers) with different combinations of numerical apertures and with different assembling materials (biocompatible) have been developed. The catheter probes have been characterized by collecting the near infrared excited Raman scattered light from cholesterol powder. The results demonstrate that the catheters with a combination of lower NA (0.12) fibers used for laser excitation and relatively higher NA (0.22) fibers for Raman signal collection will have lower background signals generated in the probes. Furthermore, the catheters with a black Teflon tubing cover and black epoxy resin adhesives were found to give better results.

Objective: The aim of this study was to assess, through Raman spectroscopy, the incorporation of calcium hydroxyapatite (CHA; ~960 cm -1 ), and scanning electron microscopy (SEM), the bone quality on the healing bone around dental implants after laser photobiomodulation (830 nm). Background Data: Laser photobiomodulation has been successfully used to improve bone quality around dental implants, allowing early wearing of prostheses. Methods: Fourteen rabbits received a titanium implant on the tibia; eight of them were irradiated with 830 nm laser (seven sessions at 48-h intervals, 21.5 J/cm 2 per point, 10 mW, ~0.0028 cm 2 , 86 J per session), and six acted as control. The animals were sacrificed 15, 30, and 45 days after surgery. Specimens were routinely prepared for Raman spectroscopy and SEM. Eight readings were taken on the bone around the implant. Results: The results showed significant differences on the concentration of CHA on irradiated and control specimens at both 30 and 45 days after surgery ( p < 0.001). Conclusion: It is concluded that infrared laser photobiomodulation does improve bone healing, and this may be safely assessed by Raman spectroscopy or SEM.