Introduction: The adjunctive use of lasers in the treatment of inflammatory periodontal diseases is gaining popularity in the dental offices. Thermal and photo-disruptive laser effects contribute to the elimination of periodontal pathogens. Clinical studies have demonstrated a highly supportive effect of many laser systems, when used in conjunction with scaling and root planing. Several in vitro studies have, however, indicated that lasers may severely damage root surface structures and inhibit new cellular attachment when certain energy levels are exceeded. The present study focuses on the structural and compositional changes induced on the root surfaces of teeth following diode laser application with increasing quantum of exposure time. Aims and objectives: To examine the structural and compositional changes on the roots of extracted human permanent teeth after application of diode lasers (810 nm). To evaluate and compare structural and compositional changes on roots of extracted human permanent teeth after diode laser application for 15, 30, 45 and 60 seconds. Materials and methods: A total of 20 single rooted extracted teeth were utilized for this study and divided into group 1: laser application for 15 seconds, group 2: laser application for 30 seconds, group 3: leser application for 45 seconds and group 4: laser application for 60 seconds. Diode laser (810 nm) application was done in the noncontact mode. A scanning electron microscope (SEM) was used to examine the cemental surface and compositional changes of the teeth in each group were further assessed using EDAX software. Results: As the exposure time of the diode laser (810 nm) on the root surface was increased, there was a concomitant increase in surface irregularities, manifested in the form of cracks and charring. There was also a decrease in the calcium and phosphorus mass percentage, as the time of laser application increased.