1. Laser Research Centre, Faculty of Health Sciences University of Johannesburg PO, Box 17011, Doornfontein Johannesburg 2028 South Africa
2. Department of Prosthodontic and Oral Rehabilitation, and Laser Therapy in Dentistry, Division, School of Oral Sciences, Health Sciences Faculty WITS University PO Box, 2010, 7 York Street Johannesburg 2193 South Africa