the regenerative procedures were performed by over-instrumentation the apices and irritating the apical tissues to induce bleeding into the root canal, then orifices plugged with MTA over blood clot and restored with GI.

photobiomodulation therapy was carried out using diode laser with wavelenght 810 nm and output power 300 mW on the apical root areas of buccal and lingual surfaces at 48 hours intervals for 2 weeks after completion of the regenerative procedures which were performed by over-instrumentation the apices and irritating the apical tissues to induce bleeding into the root canal, then orifices plugged with MTA over blood clot and restored with GI.

regenerative procedures performed in necrotic mature permanent teeth

clinical evaluation of pulp sensibility using electric pulp tester as a measurement tool

Radiographic evaluation using standardized digital radiograph that stored in computer for assessment of periapical tissues status using scoring system:

1. Score 0 - No radiological changes seen compared to preoperative radiograph
2. Score 1 - Slight decrease in radiolucency seen in periapical region
3. Score 2 - Complete reduction or resolution of radiolucency seen in periapical region.