Aim: To compare the adhesive strength of FRC glass fibers under different conditions on endodontically treated dentin of anterior teeth, using compressive strength tests.

Method: An in vitro experimental study. 60 single-rooted premolars extracted for orthodontic reasons were selected, of which 40 met the inclusion criteria. The samples were standardized using a precision cutter. Each sample underwent endodontic treatment and fillings. All samples used various root anchorage materials and were therefore divided into 4 groups: G1(N:10) First group with polyethylene FRC fibers (Ribbond- TBR Dental); G2(N:10) Second group with polyethylene FRC fibers (Construct - Kerr); G3(N:10) Third group with quartz sFRC fibers (Quartz Splint- RTD); G4(N:10) Fourth control group with glass fibers.

Each of the samples was unfilled according to the manufacturer's instructions. These materials were then placed as root anchors to subsequently create a stump. Once this was done, the samples were subjected to artificial saliva for 168 hours. The samples were then subjected to ain an Instron universal testing machine. The compression machine will exert a force at a rate of 0.5 mm per minute.