Tissue repair is an essential process that reestablishes tissue integrity and regular function. Nevertheless, different therapeutic factors and clinical conditions may interfere in this process of periapical healing. This review aims to discuss the important therapeutic factors associated with the clinical protocol used during root canal treatment and to highlight the systemic conditions associated with the periapical healing process of endodontically treated teeth. The antibacterial strategies indicated in the conventional treatment of an inflamed and infected pulp and the modulation of the host's immune response may assist in tissue repair, if wound healing has been hindered by infection. Systemic conditions, such as diabetes mellitus and hypertension, can also inhibit wound healing. The success of root canal treatment is affected by the correct choice of clinical protocol. These factors are dependent on the sanitization process (instrumentation, irrigant solution, irrigating strategies, and intracanal dressing), the apical limit of the root canal preparation and obturation, and the quality of the sealer. The challenges affecting the healing process of endodontically treated teeth include control of the inflammation of pulp or infectious processes and simultaneous neutralization of unpredictable provocations to the periapical tissue. Along with these factors, one must understand the local and general clinical conditions (systemic health of the patient) that affect the outcome of root canal treatment prediction.

ObjectiveThe aim of the study was to evaluate the effects of the capping materials mineral trioxide aggregate (MTA), calcium hydroxide (CH) and BiodentineTM (BD) on stem cells from human exfoliated deciduous teeth (SHED) in vitro. Material and MethodsSHED were cultured for 1 – 7 days in medium conditioned by incubation with MTA, BD or CH (1 mg/mL), and tested for viability (MTT assay) and proliferation (SRB assay). Also, the migration of serum-starved SHED towards conditioned media was assayed in companion plates, with 8 μm-pore-sized membranes, for 24 h. Gene expression of dentin matrix protein-1 (DMP-1) was evaluated by reverse-transcription polymerase chain reaction. Regular culture medium with 10% FBS (without conditioning) and culture medium supplemented with 20% FBS were used as controls.ResultsMTA, CH and BD conditioned media maintained cell viability and allowed continuous SHED proliferation, with CH conditioned medium causing the highest positive effect on proliferation at the end of the treatment period (compared with BD and MTA) (p<0.05). In contrast, we observed increased SHED migration towards BD and MTA conditioned media (compared with CH) (p<0.05). A greater amount of DMP-1 gene was expressed in MTA group compared with the other groups from day 7 up to day 21.ConclusionOur results show that the three capping materials are biocompatible, maintain viability and stimulate proliferation, migration and differentiation in a key dental stem cell population.

Background:Extrusion of infected debris into the periapical tissue has been cited as the major cause of postoperative pain, regardless of instrumentation technique.Aim:Comprehensively review two different kinematics of instrumentation (reciprocating and rotary) and association to the postoperative pain after endodontic treatment.Methods:Two investigators performed a systematic review with meta-analysis. MEDLINE/PubMed, Cochrane Library, and Scopus supplied relevant data from studies published until February 2018 to answer the PICO question. Primary outcome was overall postoperative pain, and the secondary outcomes were nature of the pain (mild, moderate, and severe) at 12, 24, and 48 h.Results:Ten randomized clinical trials fulfilled eligibility criteria, and five of them were submitted in the meta-analysis. Primary outcome indicated that reciprocating system results in less postoperative pain compared to rotary system (P < 0.05). As a secondary outcome, there was no statistical difference for mild, moderate, and severe pain after 12 and 24 h using reciprocating or rotary systems (P > 0.05). However, the reciprocation system showed less severe pain after 48 h (P < 0.05).Conclusion:Rotary motion had a negative impact on postoperative pain after endodontic treatment. Furthermore, after 48 h, more patients presented severe pain under rotary motion. More randomized clinical studies would be helpful.

The aim of this study was to evaluate the influence of diabetes mellitus on tissue response and mineralization ability of Sealapex ® and MTA Fillapex ® sealers. Twenty-four Wistar rats were divided into two groups: diabetic and non-diabetic. The materials were placed in polyethylene tubes and implanted into dorsal connective tissue of rats for 7 and 30 days. Six animals from each group received injection of calcein, alizarin, and oxytetracycline on days 7, 14, and 21, respectively. The animals were killed after 7 and 30 days and specimens were prepared for histologic analysis by staining with hematoxylin and eosin or Von Kossa or left unstained for polarized light or fluorescence microscopy. On day 7, inflammatory reactions were characterized. Moderate inflammatory responses were observed for all groups and on day 30, a mild inflammatory response against MTA Fillapex ® and a moderate inflammatory response against Sealapex ® were observed. Von Kossa-positive structures were observed in response to both materials and birefringent structures were observed upon polarized light analysis; these had no relation to the diabetic condition (p > 0.05). The fluorescence intensity was unaffected in diabetic rats (p > 0.05).In conclusion, diabetes mellitus did not influence the tissue response or mineralization stimulated by Sealapex ® or MTA Fillapex ® .

Aim The aim of the present study was to evaluate apical periodontitis (AP) development in rats under a chronic alcohol diet by calcium, phosphorus, and alkaline phosphatase blood levels in addition to histological and radiographic analyses. Methods Thirty‐two rats were arranged into four groups: (a) group 1: without apical periodontitis and on a regular diet; (b) group 2: AP and on a regular diet; (c) group 3: alcoholic diet without apical periodontitis; and (d) group 4: alcoholic diet and apical periodontitis. Alcoholic solution at 20% was given throughout the 8‐week experiment. AP was induced in the first molars at the end of the 7th week. At the end, the animals were anesthetized for blood collection, followed by euthanasia, and jaws were removed for digital radiography and histological processing. The level of significance was 5%. Results Calcium levels remained constant in all groups (P > 0.05). Group 4 showed a higher phosphorous level than group 2 (P < 0.05). The alkaline phosphatase activity was higher in group 3 compared with group 1 (P < 0.05). Three animals in group 4 exhibited a severe inflammatory reaction, whereas the animals in group 2 did not demonstrate any reaction (P < 0.05). The lowest value of radiographic density was given by group 4 (P < 0.05). Conclusions Chronic alcohol consumption increased serum phosphorus and decreased bone density in the periapical region, favoring AP development.