Presentation by:  P. Rechmann, D. Charland, B. Rechmann, C. Le, and J. Featherstone.

Preventive and Restorative Dental Sciences, University of California – San Francisco, San Francisco, CA

IADR General Session – Iguazu Falls, Brazil, June 20-23,212

Abstract: High caries prevalence in occlusal pits and fissures warrants novel prevention methods. In-vivo 86% reduction in smooth surface demineralization following short-pulsed 9.6!m CO2-laser irradiation was recently reported (Rechmann et al 2008, 2010).
Objectives: To conduct a blinded 12-month pilot clinical trial of occlusal pit and fissure caries inhibition using the same CO2-laser irradiation conditions.
Methods: , 20 subjects, average age 14 years (range 12–16), were recruited. At baseline, second molars were randomized into test and control groups, assessed by International Caries Detection & Assessment System (ICDAS-II) and SOPROLIFE Light-Induced Fluorescence Evaluator in daylight and blue-fluorescence mode (SOPROLIFE) (SOPRO-Acteon, La Ciotat, France). An independent investigator irradiated test molars with a CO2-laser, Pulse System Inc. (Model #LPS-500, Los Alamos, New Mexico), wavelength 9.6μm, pulse duration 20μs, pulse repetition rate 20Hz, beam diameter 800μm, average fluence 4.5±0.5J/cm2, 20 laser pulses per spot, contra-angle handpiece. At 3-, 6- and 12-month recall, teeth were assessed by ICDAS and SOPROLIFE. All subjects received fluoride varnish applications at baseline and 6-month recall.
Results: All subjects completed 3-month, 19 6-month and 16 12-month recalls. ICDAS: At 3-month, average ICDAS score changes (mean±SE) were for test -0.10±0.14 and control molars 0.30±0.18, for 6-month test -0.26±0.13 and control 0.47±0.16, and at 12-month – 0.31±0.15 and 0.75±0.17, respectively. The results showed statistically significant differences for 6 and 12-month (P=0.001 and P<0.0001, Student t-test). SOPROLIFE: SOPROLIFE blue-fluorescence revealed (area of interest better/same/worse [+1/0/-1]) at 3-month statistically
significant differences of average changes (mean±SE) for test -0.55±0.15 and for control molars 0.10±0.16 (P=0.006, Student t-test); for SOPROLIFE daylight at all recalls mean changes were statistically significantly different (P between 0.009 and 0.02).
Conclusion:  Specific CO2-pulsed-laser irradiation markedly inhibits caries progression in pits and fissures in comparison to fluoride varnish alone over 12 months. SOPROLIFE evaluations confirmed those ICDAS results.