Effect Of Different Irrigation Regimens On Endodontic Treatment Pain And Debridement Efficiency (An In Vivo / In Vitro Study)

Abstract

The aim of the present study was to evaluate endodontic treatment pain after different irrigation regimes in multiple visit endodontic therapy using negative pressure irrigating system versus conventional needle system in vivo and to compare the debridement efficiency and apical debris extrusion of negative pressure irrigation system versus conventional irrigation in vitro. The study consists of two parts; clinical part evaluating pain between visits and experimental part evaluating apical extrusion of debris and cleanliness of the canal walls. In the clinical part: Eighty mandibular vital and nonvital second premolars teeth of medically free patients. The teeth were randomly classified into main equal two groups according to the method of irrigation; Group Ι: Using negative pressure syringe (Forty patients) Group ΙΙ: Using conventional irrigation method (Forty patients). Each group was subdivided into two equal subgroups according to the vitality of the pulp; Subgroup (a): Vital teeth (Twenty patients) Subgroup (b): Non-vital teeth (Twenty patients). Each subgroup was further subdivided into two equal subdivisions according to the irrigating solutions; (1): EDTA/NaOCl (Ten patients) (2): EDTA/CHX (Ten patients) In the first visit access cavity were done, periapical tooth length radiograph and patency was established and the prepared using crown-down technique with ProTaper Universal nickel titanium rotary instruments using apex locator device. All teeth were flushed with 3ml NaOCl (2.5%) after each instrument then finally flushed with 3ml of different irrigants according to the subgroup for 2 mins. A questionnaire was given to the participants to record the pain intensity using numerical rating scale (NRS) and visual analogue scale (VAS) experienced during the treatment procedures. All questionnaires were collected from the patients in the second visit before obturation. All data were recorded and statistically analyzed. In the experimental part: Forty freshly extracted single rooted mandibular premolar teeth with mature apices and free of decay or restoration were selected. Lengths of roots were standardized by tooth decoration to length 19mm. The working lengths of the canals were measured visually with # 15 k-file until the tip of the file was just visible at the apical foramen. The root canals were classified into two equal groups according to the method of irrigation: Group Ι: Using negative pressure irrigation method; Group ΙΙ: Using conventional needle irrigation. Each subgroup will be further subdivided into two equal groups according to the irrigating solutions ten teeth in each: Group Ιa- Group ΙΙa: EDTA/NaOCl Group Ιb- Group ΙΙb: EDTA/CHX. All root canals were prepared using crown-down technique with ProTaper Universal nickel titanium rotary instruments according to manufacturer's instructions. All teeth were flushed with 3ml NaOCl (2.5%) after each instrument then finally flushed with 3ml of different irrigants according to the subgroup for 2 mins. The dry weight of extruded debris was calculated by subtracting the weight of the empty vials from the weight of the vials containing debris then analyzed. From each group five samples were randomly selected for evaluation of cleanliness of canal walls using the scanning electron microscope. The entire length of the sample was divided equally into cervical, middle and apical thirds be evaluated separately at 500× and 1000× magnification. The amounts of smear layer remaining on the surface of the root canal were evaluated by counting the opened dentinal tubules of the scanning electron microscope images for the coronal, middle, apical thirds of the root canals using computed programme ImageJ software. The amounts of remaining debris on the surface of the root canals were evaluated by scoring system. Results: The method of irrigation: the pain was minimal in EndoVac irrigation system groups than the conventional needle irrigation groups. The pain were more intense in nonvital cases than in vital once, the minimum amount of pain was with the groups using EndoVac irrigation system and the maximum was in groups using the conventional needle irrigating system. The irrigation solution: Sodium hypochlorite NaOCl is an irritant to the periapical tissue thus Gb1 was the maximum pain score recorded between groups. The pain scales: there were slightly differences between the VAS and the NRS without any significant difference between them in all groups and at the entire recorded time interval. The average mean of pain: the maximum value was in Gb1 and the minimum value was in Ga2 recorded by (VAS), the maximum value was in Gb1 and the minimum value was in Ga2 recorded by (NRS). The extrusion of debris: G2b shows the maximum amount of debris extrusion and the minimum amount was in G1a. The maximum open dentinal tubules were at the coronal segment followed by the middle and the minimum were at the apical segment with extreme significant differences between the segments At the coronal, middle and apical segment in the same group: the maximum remaining debris were at the apical segment followed by the middle and the minimum were at the coronal segment with significant differences between the coronal and apical segments and no significant differences between the coronal and middle segment.