(PR24) Evaluation of GentleWave System and Passive Ultrasonic Irrigation with Minimally Invasive and Conventional Instrumentation Against LPS in Infected Root Canals

Abstract: Minimal instrumentation has attracted interest among clinicians. However, a specific concern raised is whether the root canal enlargement achieved is enough to disinfect the root canal system. This study compared the effectiveness of GentleWave System (GWS) and passive ultrasonic irrigation (PUI) in removing lipopolysaccharides (LPS) from infected root canals after minimally invasive (MIT) and conventional instrumentation (CIT) techniques. Sixty first-premolars with two roots were inoculated with fluorescent LPS conjugate (Alexa Fluor® 594). Of the 60 teeth, twelve were submitted to confocal laser scanning microscopy (CLSM) to validate the LPS-infection model; forty-eight were randomly divided into the following groups: GWS + MIT, GWS + CIT, PUI + MIT, and PUI + CIT (all, n=12). Teeth were instrumented with Vortex Blue rotary file size 15/.04 for MIT and 35/.04 for CIT. Root canal samples were collected before (s1) and after root canal procedure (s2) and after cryogenically grinding the teeth (s3). LPS was quantified with the KQCL test. GWS + MIT and GWS + CIT were the most effective against LPS, with no difference between them (p>.05). PUI + CIT was more effective than PUI + MIT (p <.05) but less effective than GWS + MIT and GWS + CIT. GWS was most effective against LPS in infected root canals using MIT and CIT techniques.