Effects of high power diode laser and photobiomodulation therapy prior delayed replantation in rats

Abstract Introduction The search for effective protocols for a lower incidence of root resorptions reduction and for a favor periodontal repair still represents a great challenge, considering the unfavorable prognostic of the delayed replanted tooth. Objective To evaluate by histologic analyses the effects of high power diode laser and photobiomodulation on the occurrence of root resorption and on the tissue repair of delayed replanted teeth. Material and method Fifty right central incisors of Wistar rats were used. After the extraction, the specimens were assigned to 5 groups (n=10): G1 and G2 were the control groups-with no treatment and they were respectively submitted to immediate and delayed replantation (DR- 60 minutes after the extraction). The other three groups received tissue repair treatment prior the DR: G3 - root surfaces were irradiated with high power laser (810 nm, 1.5 W); G4- root surfaces and the alveolar wounds were irradiated with low power laser (photobiomodulation), respectively with 660 nm, 90 mW and 780 nm, 40 mW; G5- root surfaces were irradiated with high power and the alveolar wound received photobiomodulation with the same parameters used in G3 and G4. After 60 days the animals were euthanized. The specimens were processed for histological analyses. Result The histologic analysis showed lower means values of scores of root reabsorptions and ankylosis in G3 and G5 when compared to G2 and G4 (Kruskall-Wallis test, p>0.05). Regarding the periodontal repair, all the experimental groups (G3, G4 and G5) presented lower means values of scores than G1 (Kruskall-Wallis test, p <0.05) and similar values to G2 (Kruskall-Wallis test, p>0.0.5). Conclusion High power laser reduced the occurrence of root resorption and photobiomodulation did not enhance the tissue healing process in delayed tooth replantation in rats.