Influence of ethylenediaminetetraacetic acid irrigation on the regenerative endodontic procedure in an immature rat molar model

Abstract

Aim: To analyse the influence of ethylenediaminetetraacetic acid (EDTA) on the repair process in immature rat molars after a regenerative endodontic procedure (REP). Methodology:The lower first molars of 12 4-week-old Wistar rats underwent pulpectomy in the mesial root and were divided into the following groups: sodium hypochlorite (NaOCl; n = 6) -the mesial canals were irrigated with 2.5% NaOCl for 5 min, and NaOCl-EDTA (n = 6) -the canals were irrigated with 2.5% NaOCl, followed by 17% EDTA for 5 min each. After evoking bleeding using a size 10 K-file, the cavities were sealed. Three molars on the untreated side were randomly used as control (control-15 d; n = 3), and three molars from the other three rats untreated were used as immediate control (n = 3). After 15 days (NaOCl, NaOCl-EDTA and control-15 d groups) or immediately (control-immediate), the animals were euthanized, and the teeth were subjected to histologic evaluation of tissue regeneration and presence of collagen fibres. Mann-Whitney U-test was used (p < .05). Results:The experimental groups had newly formed cementum-like tissue and increased root length and thickness. Half of the specimens in NaOCl-EDTA group showed apical foramen closure, whilst the NaOCl group had partial apical closure.The experimental groups showed inflammatory infiltrate extending mainly to the medium third of the root canal. These parameters were similar between experimental groups (p > .05). Newly formed connective tissue in the pulp space was significantly higher in the NaOCl-EDTA group than in NaOCl group (p < .05). Regarding the collagen fibres, the NaOCl-EDTA group had more collagen fibres in the root tip, but there was no significant difference compared to NaOCl group, and both groups showed greater amount of immature fibres in this area; in the centre of the apical third of root canal, there was equivalence between mature and immature fibres from both groups (p > .05).

Final irrigation with bioglass solution in regenerative endodontic procedure induces tissue formation inside the root canals, collagen maturation, proliferation cell and presence of osteocalcin

“…The data of REP‐SS corroborate with the previous results of Reis‐Prado et al. (2023), which showed that the use of EDTA in REP increased the deposition of mineralized tissue in the root. However, the REP‐F18Co group had significant greater OCN immunolabelling.…”

“…It was found that the F18Co bioglass solution induced the formation of connective tissue inside the root canal, with collagen maturation, the presence of PCNA-positive cells and higher OCN immunolabelling, whilst did not influence the formation of mineralized tissue on the walls of the root canal. Wistar rat molars were used because they provide an acceptable and previously standardized model (Reis-Prado et al, 2023). These animals exhibit biological responses and repair processes, and histological characteristics similar to those of humans (Cintra et al, 2016;Dammaschke, 2010;Sasaki & Kawamata-Kido, 1995).…”

“…The animals were anaesthetised via intramuscular injection using ketamine 10% (80 mg/Kg; Ketamina Agener 10%, União Química Farmacêutica Nacional S/A, Embu‐Guaçu, São Paulo, Brazil) and xylazine 2% (15 mg/Kg; Xilazin, Syntec do Brasil LTDA, Cotia, São Paulo, Brazil). The upper left or right first immature molars of the animals were used, and the protocol operative was based on a previous study (Reis‐Prado et al., 2023). The teeth were isolated with a especial dental clamp that was sealed by a gingival barrier (Top dam, FGM, Joinville, SC, Brazil), preventing any contact with saliva (File S1).…”

“…The working length was defined using the right and left upper molars of one animal of the same age within the same experiment. After endodontic access, a radiograph was taken with a size 10 K‐file introduced to a length of 4 mm in the mesial canal of the first molars, according to a previous study (Reis‐Prado et al., 2023). This procedure confirmed a root canal length of 4 mm on both sides.…”

Revascularization of a Permanent Tooth with Necrotic Pulp and Apical Periodontitis

“…However, a recent study, 24 conducted using an immature rat molar model, suggested that EDTA irrigation may have a detrimental effect on the regenerative process. This underscores the importance of careful consideration when employing EDTA in regenerative endodontics and highlights the need for further research to determine the optimal irrigation solution.…”