Periapical PeriodontitisPulpectomyPeriapical DiseasesPeriodontitisPeriapical TissueChronic PeriodontitisPeriapical GranulomaAggressive PeriodontitisPeriapical AbscessRoot Canal TherapyDental Pulp NecrosisAlveolar Bone LossPeriodontal PocketRadiography, BitewingRadicular CystRoot Canal ObturationDental Pulp ExposureDental Pulp CavityPeriodontal Attachment LossPorphyromonas gingivalisGingivaGingival Crevicular FluidRoot Canal Filling MaterialsGingival HemorrhageGingivitisCalcium HydroxidePeriodontal IndexApicoectomyPulpitisRadiography, Dental, DigitalApexificationDental ScalingAggregatibacter actinomycetemcomitansDental FistulaDental Pulp DiseasesGutta-PerchaRoot Canal PreparationDental Plaque IndexDental PlaqueTooth, NonvitalCutaneous FistulaFistulaGastric FistulaArteriovenous FistulaIntestinal FistulaBronchial Fistula