Aim: Aim of this review was to present a comprehensive outline of the use of hard tissue lasers in Periodontics with respect to non-surgical periodontal treatment. Materials and method: Electronic databases of PubMed and Cochrane Library were searched from 1992 to 2018. 18 clinical studies were evaluated after the inclusion, exclusion criteria. Results: It was deduced that Er:YAG laser is a feasible option for non-surgical periodontal therapy if proper parameters are followed i.e. the energy in the range of 140-160 mJ and frequency of 10 Hz. None of the studies favoured the use of Nd:YAG and CO2 laser because of their prospective adverse effects. Conclusion: It can be concluded that Er:YAG laser application in non-surgical periodontal therapy is valuable. In combination with mechanical debridement, the results are similar or better with significant gains in clinical attachment level as compared to other various lasers. It is an excellent alternative to control the proliferation of micro-organisms. Nd:YAP, diode and other low power lasers can be used but with caution since they offer no additional advantage over conventional treatment modalities.
Keywords: CO laser; Er:YAG laser; lasers; non-surgical periodontal therapy.