Failed Regenerative Endodontic Case Treated by Modified Aspiration-irrigation Technique and Apexification.

AIM: This report addresses the management of a large persistent discharging lesion in an 11-year-old boy. The report describes the use of aspiration-irrigation technique for the management of immature necrotic tooth with persistent discharge after a failed regenerative procedure. BACKGROUND: Regenerative endodontics aim to provide an increase in root canal width, length, and in apical closure. Alternative procedures, such as apexification, should be attempted when regeneration fails. If the canal cannot be dried to persistent discharge, the aspiration-irrigation technique can be used. The technique relies on using aspiration along with irrigation to remove pus from the periapical area. CASE DESCRIPTION: This is a case for an 11-year-old patient who had trauma to tooth #11, which resulted in the complicated crown fracture. He had an emergency management that included pulpectomy and intracanal medication at another clinic. Two years later, the patient was presented to our clinic. Upon examination, the diagnosis was previously initiated therapy with asymptomatic apical periodontitis in immature tooth #11. Regeneration was attempted first but failed. The mineral trioxide aggregate (MTA) plug was removed, and the canal had persistent pus discharge. The canal was filled with intracanal medication, and then 2 weeks later, the canal was filled with triple antibiotic paste (TAP). Next visit, and due to continuous discharge, tooth #11 was treated conservatively with an intracanal aspiration-irrigation technique. An IrriFlex needle attached to a high-volume suction was used to aspirate the cystic fluid. Mineral trioxide aggregate plug apexification was performed in a later visit and the tooth was restored. CONCLUSION: During the 3-month and 16-month follow-up, there was resolution of the symptoms, a decrease in the periapical lesion size, and soft tissues appeared within normal limits. CLINICAL SIGNIFICANCE: Regenerative procedures are a good option for immature necrotic teeth. These procedures may fail due to persistent pus discharge from the root canals. The aspiration-irrigation technique is a good treatment option in cases of consciously discharging canals. How to cite this article: Alsofi L, Almarzouki S. Failed Regenerative Endodontic Case Treated by Modified Aspiration-irrigation Technique and Apexification. J Contemp Dent Pract 2024;25(1):92-97.

The clinical outcomes of vital intact teeth close to large cystic lesions of endodontic origin: A prospective clinical study.

AIM: To evaluate the indication of the endodontic treatment for vital intact teeth with the root apex involved in large radicular cystic lesions of endodontic origin. METHODOLOGY: This prospective cohort study enrolled healthy participants with radicular cysts of endodontic origin and with the root apex of vital intact teeth involved in the bone defect, as determined by cone beam computed tomography (CBCT). Thirty-two sound vital teeth were analysed by thermal (TPT) and electric pulp tests (EPT) before surgery (T0) and 1 week (T1), 2 weeks (T2), 3 months (T3) and 6 months (T4) post-surgery. Student's t-test (p < .05) was used to compare the EPT values at baseline and T4. anova (p < .05) was used to analyse the EPT variations for all maxillary and mandibular teeth. McNemar test (p < .05) was used to compare the results according to variation in EPT values gathering by variation, no variation and no response. RESULTS: At T1, 75 and 65.7% of teeth responded positively whilst 25 and 34.3% did not respond to EPT and TPT, respectively. The variation of the EPT values between T0 and T1 was observed for 50.0% of teeth, whilst no variation was noticed in 25.0% of teeth. At T4, 90.6 and 87.5% of teeth responded positively whilst 9.4 and 12.5% did not respond to EPT and TPT, respectively. At T4, variation of the EPT values between T0 and T4 was observed for 28.1%, whilst no variation was noticed in 62.5% of teeth. There were no statistical differences in EPT results between T0 and T4 (p > .05), but significant differences were observed for EPT values between T1 and T4 (p < .05), and between mandibular and maxillary teeth. The pulp sensibility of maxillary teeth worsened after surgery, before reverting progressively to T0 values, whilst no statistically significant differences were observed for mandibular teeth at the different time points. CONCLUSIONS: These data support the inconsistence of the prophylactic endodontic treatment in healthy vital teeth with apex involvement in large cystic lesions of endodontic origin. Post-surgery follow-up with TPT and EPT is recommended to assess pulp status.

Revolutionizing Endodontics: Innovative Approaches for Treating Mature Teeth With Closed Apices and Apical Lesions: A Report of Two Cases.

INTRODUCTION: Modern tissue engineering strategies have elucidated the potential of regenerative endodontic treatment (RET) as an alternative for treating mature teeth. METHODS: Here, we report two cases in which cell-based RET (CB-RET) using encapsulated allogeneic umbilical cord mesenchymal stem cells (UC-MSCs) in a platelet-poor plasma (PPP)-based scaffold was used in two mature teeth with pulp necrosis and apical periodontitis. RESULTS: After 5 years of follow-up, the healing response was satisfactory in both cases, with evidence of pulp revitalization. CONCLUSIONS: This is the first study to report the success of an extended, 5-year follow-up for allogeneic CB-RET. This report presents an innovative and sustainable solution to challenging endodontic scenarios.

Allogeneic Bone Marrow Mesenchymal Stromal Cell Transplantation Induces Dentin Pulp Complex-like Formation in Immature Teeth with Pulp Necrosis and Apical Periodontitis.

INTRODUCTION: Dental pulp regeneration is challenging in endodontics. Cellular therapy is an alternative approach to induce dental pulp regeneration. Mesenchymal stromal cells (MSCs) have the capacity to induce dental pulp-like tissue formation. In this study, we evaluated the capacity of allogeneic bone marrow MSCs (BM-MSCs) to regenerate pulp following necrosis and apical periodontitis in children's permanent immature apex teeth. METHODS: Patients aged 8 to 12 years with pulp necrosis and apical periodontitis were evaluated. The study included 15 teeth (13 incisors and 2 molars) from 14 patients (8 boys and 6 girls). Radiographic evaluation showed periapical radiolucency and immature apex teeth. There was no response to cold or electric pulp testing. The root canal of each tooth was cleaned, shaped, and Ca(OH)2 used as an interappointment medication. Cryopreserved allogeneic BM-MSCs were thawed, expanded, incorporated into preclotted platelet-rich plasma, and implanted into the tooth's pulp cavity. They were sealed with bioceramic cement and composite. Sensibility, apical foramen, calcium deposits within the root canal, and resolution of periapical lesions were evaluated in each tooth over the following 12 months. RESULTS: Based on 9 variables established for dental pulp-like tissue regeneration, all MSC-treated teeth showed evidence of successful regeneration. Clinical and radiographic evaluation of the treated teeth showed periapical lesion healing, sensitivity to cold and electricity, decreased width of the apical foramen, and mineralization within the canal space. CONCLUSIONS: Transplantation of allogeneic MSCs induces the formation of dental pulp-like tissue in permanent immature apex teeth with pulp necrosis and apical periodontitis. Implant of MSCs constitutes a potential therapy in regenerative endodontics in pediatric dentistry. Future studies incorporating a larger sample size may confirm these results.

Effect of Recombinant Human Platelet-Derived Growth Factor on Healing of Chronic Periapical Tissue Pathosis Following Apical Surgery in a Canine Model: A Histomorphometric and Microcomputed Tomography Analysis.

This canine in vivo study assessed the effect of recombinant human platelet-derived growth factor (rhPDGF) on the healing of periapical tissues following apical surgery. From a total of 96 premolar teeth, 64 teeth from six beagle dogs (2 years old) were classified as experimental and were randomly assigned to four experimental groups (16 teeth per group). After having the pulp extirpated, leaving teeth open to the oral cavity for 1 week, and sealing with an immediate restorative material for 8 weeks, nonsurgical endodontic treatment was performed. A split-mouth design was used, and intra-animal randomization of treatment sides was applied to the groups as follows: apical curettage + 1.5-mm root-end resection (Group 1); apicoectomy + mineral trioxide aggregate (MTA) root-end filling (Group 2); apicoectomy + MTA root-end filling + rhPDGF (Group 3); and apical curettage + rhPDGF (Group 4). The animals were sacrificed 24 months after apical surgery, and histologic and µCT analyses were performed for bone volume loss (BVL). Group 1 showed partial resolution of the periapical lesions without signs of tissue regeneration (BVL: 49.09 ± 10.97 mm3). Group 2 had minimal bone regeneration and showed cementum reformation in 9 teeth, with no direct attachment to the MTA (BVL: 35.34 ± 10.97 mm3). Group 3 showed regeneration of all damaged apical tissues without direct contact between the cementum and MTA (BLV: 4.51 ± 1.55 mm3). Group 4 showed regeneration of PDL, bone, and cementum and attachment of functional cementum fibers (BVL: 2.82 ± 2.3 mm3). The difference in BVL was statistically significant only for Groups 1 and 2 (P < .05). rhPDGF may help regenerate apical tissue structures following apical surgery.

Evaluating In Vitro Performance of a Novel Stainless Steel Rotary System (Gentlefile) Based on Debris Extrusion and Instrumentation Time.

The new Gentlefile (GF) system, made of stainless steel and developed by MedicNRG in Kibbutz Afikim, Israel, claims to have advantages over traditional nickel-titanium files. However, research has shown that nickel-titanium files are mechanically superior due to their increased flexibility, cutting efficiency, and ability to maintain canal anatomy with less risk of procedural errors. This study compared the amount of debris extrusion and the time required for root canal instrumentation using GF versus the nickel-titanium ProTaper Universal (PTU) system and a manual step-back (MSB) stainless steel technique. This in vitro experimental study utilized 66 extracted human single-canal mandibular premolars with mature apices and root curvature of less than 10 degrees. The teeth were randomly divided into three groups (n = 22) and standardized for working length before being placed in preweighed vials. Group 1 was instrumented with PTU, Group 2 with GF, and Group 3 with the MSB technique. Extruded debris was collected in the vials, dried in an incubator, and weighed using the same scale. The change in weight indicates the debris amount. Instrumentation time was recorded using a stopwatch. The normal distribution of data was assessed using the Kolmogorov-Smirnov test. The groups were then compared regarding the amount of extruded debris and instrumentation time using the Kruskal-Wallis test and one-way ANOVA, followed by the Games-Howell test, respectively (alpha = 0.05). No significant difference in apical debris extrusion was found among the three groups (P > 0.05). However, a significant difference in instrumentation time was detected between the groups (P < 0.05). MSB instrumentation took significantly longer than both the PTU (P = 0.001) and GF (P = 0.001) systems. The GF system did not demonstrate reduced apical debris extrusion or faster instrumentation time compared to PTU. MSB had the longest instrumentation time compared to the other techniques.

[Effects and mechanism of glycine on rat cardiomyocytes pretreated with serum from burned rats].

Objective: To investigate the effect and mechanism of glycine on rat cardiomyocytes pretreated with serum from burned rats (hereinafter referred to as burn serum). Methods: Experimental research methods were adopted. Thirty gender equally balanced Wistar rats aged 7 to 8 weeks were collected, 10 of which were used to prepare normal rat serum (hereinafter referred to as normal serum), and the other 20 were inflicted with full-thickness burn of 30% total body surface area to prepare burn serum. Primary cardiomyocytes were isolated and cultured from the apical tissue of 180 Wistar rats aged 1 to 3 days by either gender for follow-up experiments. Cells were divided into normal serum group and burn serum group treated with corresponding serum according to the random number table (the same grouping method below). Trypanosoma blue staining was performed at post treatment hour (PTH) 1, 3, 6, 9, and 12 to detect the cell survival rate. Cells were divided into burn serum alone group treated with burn serum for 6 h followed by routine culture of 30 min and 0.4 mmol/L glycine group, 0.8 mmol/L glycine group, 1.2 mmol/L glycine group, 1.6 mmol/L glycine group, and 2.0 mmol/L glycine group treated with burn serum for 6 h followed by culture of 30 min with corresponding final molarity of glycine, i.e., at post intervention hour (PIH) 6.5, the cell survival rate was detected as before. Cells were divided into normal serum group, burn serum alone group, 0.8 mmol/L glycine group, 1.2 mmol/L glycine group, and 1.6 mmol/L glycine group, with the same intervention of 6.5 h as before, respectively. The content of adenosine monophosphate (AMP) and adenosine triphosphate (ATP) was detected by high performance liquid chromatography, and the AMP/ATP ratio was calculated. The protein expressions of phosphorylated mammalian target of rapamycin complex 1 (p-mTORC1), phosphorylated p70 ribosomal protein S6 kinase (p-p70 S6K), phosphorylated eukaryotic translation initiation factor 4E-binding protein 1 (p-4E-BP1), and phosphorylated AMP-activated protein kinase (p-AMPK) were detected by Western blotting. Cells were divided into normal serum group, burn serum alone group, 0.8 mmol/L glycine group intervened as before and 0.8 mmol/L glycine+25 ng/mL rapamycin group treated with burn serum followed by culture with two reagents. The expressions of heat shock protein 70 (HSP70), metallothionein (MT), and tubulin were detected by immunofluorescence method after 30 min of corresponding culture at PTH 1, 3, and 6, i.e., at PIH 1.5, 3.5, and 6.5, and the microtubule morphology was observed at PIH 6.5. The sample number at each time point was 10. Data were statistically analyzed with analysis of variance for factorial design, one-way analysis of variance, least significant difference (LSD)-t test, LSD test, and Bonferroni correction. Results: At PTH 1, 3, 6, 9, and 12, the cell survival rates in burn serum group were significantly lower than those in normal serum group (with t values of 4.96, 16.83, 35.51, 34.33, and 27.88, P<0.05). In burn serum group, the cell survival rate at PTH 3, 6, 9, or 12 was significantly lower than that at PTH 1 (P<0.05), the cell survival rate at PTH 6, 9, or 12 was significantly lower than that at PTH 3 (P<0.05), and the cell survival rate at PTH 6 was similar to that at PTH 9 (P>0.05) but significantly higher than that at PTH 12 (P<0.05). Treatment of 6 h was selected as the follow-up intervention time of burn serum. At PIH 6.5, compared with that in burn serum alone group, the cell survival rate in each glycine group was significantly increased (P<0.05). The cell survival rate in 0.8 mmol/L glycine group was the highest, and 0.8, 1.2, and 1.6 mmol/L were selected as subsequent glycine intervention concentrations. At PIH 6.5, the AMP/ATP ratio of cells in burn serum alone group was significantly higher than that in normal serum group, 1.2 mmol/L glycine group, or 1.6 mmol/L glycine group (P values all <0.05), and the AMP/ATP ratio of cells in 1.6 mmol/L glycine group was significantly lower than that in 0.8 mmol/L glycine group (P<0.05). At PIH 6.5, the protein expressions of p-mTORC1, p-p70 S6K, and p-4E-BP1 of cells in normal serum group, burn serum alone group, 0.8 mmol/L glycine group, 1.2 mmol/L glycine group, and 1.6 mmol/L glycine group were 1.001±0.037, 0.368±0.020, 1.153±0.019, 1.128±0.062, 1.028±0.037, 0.96±0.07, 0.63±0.12, 1.17±0.13, 1.13±0.16, 1.11±0.11, and 0.98±0.06, 0.45±0.08, 1.13±0.05, 0.77±0.12, 0.51±0.13. Compared with those in burn serum alone group, the protein expressions of p-mTORC1, p-p70 S6K, and p-4E-BP1 of cells in normal serum group and each glycine group were significantly increased (P<0.05), while the protein expressions of p-AMPK were significantly decreased (P<0.05). Compared with those in 0.8 mmol/L glycine group, the protein expression of p-4E-BP1 of cells in 1.2 mmol/L glycine group and the protein expressions of p-mTORC1 and p-4E-BP1 of cells in 1.6 mmol/L glycine group were significantly decreased (P<0.05). Compared with those in 1.2 mmol/L glycine group, the protein expressions of p-mTORC1 and p-4E-BP1 of cells in 1.6 mmol/L glycine group were significantly decreased (P<0.05), while the protein expression of p-AMPK was significantly increased (P<0.05). Compared with those in normal serum group, the expression of tubulin of cells in burn serum alone group was significantly decreased at PIH 1.5, 3.5, and 6.5 (P<0.05), while the expression of HSP70 of cells at PIH 1.5 and 3.5 and the expression of MT at PIH 3.5 and 6.5 were significantly increased (P<0.05). The expressions of HSP70 and MT of cells at PIH 1.5, 3.5, and 6.5 and the expression of tubulin at PIH 1.5 and 3.5 in burn serum alone group and 0.8 mmol/L glycine+25 ng/mL rapamycin group were significantly lower than those in 0.8 mmol/L glycine group (P<0.05). At PIH 6.5, compared with that in normal serum group, the cell microtubule structure in burn serum alone group was disordered; the cell boundary in 0.8 mmol/L glycine group was clearer than that in burn serum alone group, and the microtubule structure arranged neatly near the nucleus. Compared with that in 0.8 mmol/L glycine group, 0.8 mmol/L glycine+25 ng/mL rapamycin group had unclear cell boundaries and disordered microtubule structure. Conclusions: Burn serum can cause cardiomyocytes damage in rats. Glycine can significantly up-regulate mammalian target of rapamycin/p70 ribosomal protein S6 kinase/eukaryotic translation initiation factor 4E-binding protein 1 signaling pathway through AMP-activated protein kinase, promote the synthesis of protective proteins HSP70, MT, and tubulin, stabilize the microtubule structure, and exert cardiomyocytes protection function.

An Innovative Technique for Ejaculation-Sparing Prostatic Enucleation with Thulium:YAG Laser.

Purpose: We report our experience with 100 patients who underwent an innovative prostate enucleation technique that spares the complete urethral-plate from the veru montanum to the bladder neck using a low-energy thulium laser emission. The aim of our study was to evaluate the short-term effects of this procedure on ejaculation preservation and urinary obstruction. Materials and Methods: The International Prostate Symptom Index (IPSS), quality of life (QoL), and Male Sexual Health Questionnaire Ejaculatory Dysfunction (MSHQ-EJD) Short Form were used as validated instruments to quantify ejaculatory dysfunction before and 6 months after the surgery. Results: The median IPSS score pre- and postoperatively was 20 and 5, respectively (p < 0.0001); QoL dropped from a median of 4-1 (p < 0.0001); and the mean preoperative maximal flow rate improved significantly (8.5 vs 21.2 mL/min) (p < 0.0001). Furthermore, there was significant reduction in postvoid residual postoperatively (p < 0.0001). Postoperative ejaculatory function was preserved in 92/100 patients (92%). According to the MSHQ-EJD score, patients reported a slight nonsignificant decrease in frequency of ejaculation (item 1), force of expulsion (item 2) and reduction in semen volume during ejaculation (item 3), with the exception of ejaculation discomfort (item 4). Conclusion: According to our results, complete removal of the apical tissue, which has been advocated as an integral part of the so called ejaculatory hood, does not interfere with ejaculation if the ventral lissosphincter remains intact.

[Electroacupuncture improves ischemic myocardial injury by activating Nrf2/HO-1 signaling pathway to inhibit ferroptosis in rats].

OBJECTIVE: To explore the role of nuclear factor E2 related factor 2 (Nrf2) / heme oxygenase (HO-1) signal pathway in electroacupuncture (EA) induced improvement of acute myocardial ischemia (AMI) and its relationship with ferroptosis in rats. METHODS: Male SD rats were randomly and equally divided into sham operation, model, EA and EA+ML385 (inhibitor of Nrf2) groups (n=8). The rat model of AMI was established by ligating the descending anterior branch of the left coronary artery. EA (2 Hz/100 Hz) was applied to bilateral "Shenmen"(HT7) and "Tongli"(HT5) for 20 min, once daily for 7 days. The electrocardiogram (ECG) of standard Ⅱ (ECG ST) lead and heart rate (HR) in each group was recorded and analyzed before and after modeling and after treatment by using PowerLab physiological recorder system. Histopathological changes of myocardial tissue were observed by H.E. staining, and the ultrastructure of myocardiocytes of cardiac apical tissue was observed under transmission electron microscope. The contents of Fe2+ and glutathione (GSH) in the myocardial tissue were measured by chromato-metry. The protein expression levels of Nrf2, HO-1, glutathione peroxidase 4 (GPX4), ferritin heavy chain polypeptide 1 (FTH1) and long chain acyl CoA synthase 4 (ACSL4) in the myocardial tissue were detected by Western blot. RESULTS: Compared with the sham operation group, the HR, ECG ST, Fe2+ content, expression levels of Nrf2, HO-1, FTH1 and ACSL4 proteins in myocardial tissues were significantly increased (P<0.01), while GSH content and GPX4 protein expression considerably decreased (P<0.01) in the model group. Compared with the model group, both EA and EA+ML385 groups had an obvious decrease in HR, Fe2+ content, and ACSL4 levels (P<0.01), and an increase in the expression levels of GPX4 and FTH1 proteins (P<0.01), EA (rather than EA+ML385) effectively down-regulated ECG ST, and up-regulated GSH, Nrf2 and HO-1 (P<0.01), whereas EA+ML385 apparently down-regulated expression levels of Nrf2 and HO-1 (P<0.01). It shows that ML385 pronouncedly weaken the effects of EA in slowing down ECG ST and HR, down-regulating Fe2+ content and ACSL4 expression (P<0.01), up-regulating GSH content, Nrf2, HO-1, GPX4 and FTH1 expressions (P<0.01). H.E. staining showed disordered arrangement and hyperplasia of myocardiocytes, enlarged myocardial fiber gap, agglomerated and deeply stained myoplasma, and some broken myocardial fibers with irregular mass and local tissue fibrosis in the model group, which was relatively milder in both EA and EA+ML385 groups. Compared with the sham operation group, the model group showed decreased mitochondrial atrophy, increased membrane density, and disappearance or reduction of cristae in myocardial cells，which was improved in the EA group. CONCLUSION: EA of HT7 and HT5 has a protective effect on ischemic myocardium in rats, which may be related to its effects in reducing oxidative stress by regulating Nrf2/HO-1 signaling pathway, and inhibiting "iron death" of myocardial cells.

Relación entre el seno maxilar y ápices de dientes postero- superiores con tomografía computarizada de haz cónico / Relationship between the maxillary sinus and apices of posterior-superior teeth using cone beam computed tomography

El conocimiento de la relación entre el seno maxilar y los ápices de los dientes posterosuperiores es fundamental para evitar complicaciones frente a distintos tratamientos. Estudio descriptivo de corte transversal, con muestra por conveniencia de 383 imágenes de raíces de dientes posterosuperiores obtenidas por medio de tomografía computarizada de haz cónico (TCHC) de un centro radiológico en Viña del Mar, Chile. Cada raíz fue clasificada según su relación vertical con el seno en 4 categorías (0: ápice no se encuentra en contacto con contorno inferior del seno; 1: ápice en contacto con seno; 2: ápice lateralmente al seno; 3: ápice se protruye en seno). Además se midió su distancia en mm. Los datos fueron analizados con estadística descriptivas. El diente más lejano al seno maxilar fue el primer premolar superior (4.2 mm), seguido por el segundo premolar superior (1 mm). En el primer molar superior la raíz más lejana fue la mesio-vestibular (MV) 1mm, seguida por la raíz disto-vestibular (DV) 0.6mm y la raíz palatina (P) -1mm. En el segundo molar superior la raíz más lejana fue P 0.4mm, luego la DV 0.3mm, y MV -0,11mm. En cuanto a las categorías, se observó que la mayoría de las raíces se encuentran alejadas del seno siendo la raíz P del primer molar superior y la raíz MV del segundo molar superior las que se encuentran mayormente protruidas (42 % y 26 % respectivamente). El primer premolar es el diente posterosuperior que se encuentra más alejado del seno maxilar y a medida que se avanza hacia posterior hay tendencia a disminuir la distancia entre los ápices y el seno maxilar.

SUMMARY: Knowledge of the relationship between the maxillary sinus and the apices of the upper posterior teeth is crucial to avoid complications when considering different treatments. A descriptive cross-sectional study was carried out, with a convenience sample of 383 images of upper posterior teeth roots, obtained by means of cone beam computed tomography (CBCT) from a radiological center in Viña del Mar, Chile. Each root was classified according to its vertical relationship with the sinus into 4 categories (0: apex is not in contact with the lower contour of the sinus; 1: apex is in contact with the sinus; 2: apex laterally to the sinus; 3: apex protrudes in sinus). In addition, its distance was measured in mm. The data were analyzed with descriptive statistics. The tooth farthest from the maxillary sinus was the maxillary first premolar (4.2 mm), followed by the maxillary second premolar (1 mm). In the upper first molar, the most distant root was the mesiobuccal (MV) 1mm, followed by the distobuccal root (DV) 0.6mm and the palatal root (P) -1mm. In the upper second molar, the furthest root was P 0.4mm, then DV 0.3mm, and MV -0.11mm. In reference to the categories, it was observed that most of the roots are far from the sinus, with the P root of the first upper molar and the MV root of the second upper molar being the most protruding (42 % and 26 % respectively). The first premolar is the posterior maxillary tooth that is furthest from the maxillary sinus and as one advances posteriorly there is a tendency to decrease the distance between the apices and the maxillary sinus.

Impacts of different Nickel-Titanium rotary and reciprocating root canal preparation systems on the amount of apically extruded debris.

This study aimed to evaluate the amount of apically extruded debris caused by different NiTi files. One hundred mandibular premolars were included in this study. The specimens were divided into five groups (n = 20): (i) TruNatomy, (ii) WaveOne Gold, (iii) 2Shape, (iv) ProTaper Next and (v) Reciproc Blue. The extruded debris was collected into preweighed Eppendorf tubes. These tubes were weighed again, and the net weight of debris was calculated. Data were statistically analysed, and the significance level was set at 5%. The least amount of extruded debris was observed in the TruNatomy group (p < 0.05). Statistically significant differences were not found among (iii), (iv) and (v) groups (p > 0.05). However, these groups resulted in significantly higher amounts of debris when compared to (i) and (ii) groups (p < 0.05). The results lead us to conclude that all instrumentation systems caused apical extrusion of debris at varying weights.

Removal of separated instruments from unfavourable locations: Case reports using the HBW ultrasonic ring or a surgical approach.

Two patients were admitted to the dental clinic to evaluate two right mandibular first molars (both FDI no. 46). In Case 1, there was an accidental instrument separation, which was thought to have been bypassed; however, the instrument was located beyond the apical foramen, in the alveolar bone. The 1-week follow-up revealed that the fragment was close to the inferior alveolar nerve, thus allowing surgical removal to be performed. In Case 2, two separated instruments located in the apical third of the mesiobuccal and mesiolingual canals were removed using the HBW ultrasonic ring coupled to ISO 10 and 15 hand instruments. The 3-month and 1-year follow-ups (Case 1), and the 2-year and 3-year follow-ups (Case 2) showed a favourable evolution in both cases. It can be concluded that both the surgical approach and the HBW ultrasonic ring are viable options for the removal of separated instruments in unfavourable locations.

Morphological alterations of the apical foramen after foraminal enlargement: a systematic review of ex vivo studies / Alterações morfológicas do forame apical após ampliação foraminal: uma revisão sistemática de estudos ex vivo

Foraminal enlargement has been recommended to optimize the disinfection of infected root canals, although some authors still claim that the foramen should be kept in its original shape and position. This study aimed to evaluate morphological alterations of apical foramen after foraminal enlargement through a systematic review. An electronic search was conducted until April 2022. Ex vivo studies evaluating influence of foraminal enlargement in the morphologic changes of apical foramen were included. Studies without a control group or available full text were excluded. Foraminal deformation and area increase were considered as primary outcomes. Risk-of-bias assessment was performed according to a modified Joanna Briggs Institute's Checklist. From 702 studies retrieved, five were eligible. Most studies used single-rooted teeth, and rotary systems for instrumentation ranging from ­ 2 mm to + 1 mm to the apex. All studies found increased major foramen deformation after foraminal enlargement. Among four studies that evaluated foraminal area, all found increased area after foraminal enlargement. Insufficient data for touched/untouched walls by instruments and dentinal microcrack formation was observed. A low risk of bias was found. Foraminal enlargement during root canal preparation seems to increase deformation and major apical foramen area. Future investigations with standardized methodologies are encouraged (AU)

A ampliação foraminal tem sido recomendada para otimizar a desinfecção de canais radiculares infectados, embora alguns autores ainda afirmem que o forame deve ser mantido em sua forma e posição originais. Este estudo teve como objetivo avaliar alterações morfológicas do forame apical após ampliação foraminal por meio de uma revisão sistemática. Uma busca eletrônica foi realizada até abril de 2022. Foram incluídos estudos ex vivo que avaliaram a influência da ampliação foraminal nas alterações morfológicas do forame apical. Foram excluídos estudos sem grupo controle ou com texto completo indisponível. A deformação foraminal e o aumento da área foram considerados desfechos primários. A avaliação do risco de viés foi realizada de acordo com uma lista de verificação modificada do Instituto Joanna Briggs. Dos 702 registros recuperados, cinco foram elegíveis. A maioria dos estudos utilizou dentes unirradiculares e sistemas rotatórios para instrumentação, com comprimento de trabalho variando de ­ 2 mm a + 1 mm até o ápice. Todos os estudos encontraram aumento da deformação do forame maior após ampliação foraminal. Dos quatro estudos que avaliaram a área foraminal, todos encontraram aumento de área após alargamento foraminal. Foram observados dados insuficientes para paredes tocadas/intocadas pelos instrumentos e formação de microfissuras dentinárias. Um baixo risco de viés foi encontrado. A ampliação foraminal durante o preparo do canal radicular parece aumentar a deformação e a área do forame apical. Futuras investigações com metodologias padronizadas são incentivadas (AU)

Influence of different working lengths on the shaping ability of Reciproc Blue in the apical third and apical foramen: a micro-computed tomographic study

Aim: This study aimed to assess the shaping ability of Reciproc Blue in the apical third and apical foramen of moderately curved canals at different working lengths (WLs), by micro-computed tomography. Methods: Thirty-six mesial roots (mesiobuccal and mesiolingual canals) were included, each with 2 separate root canals and independent apical foramina, according to type IV of Vertucci's classification of first and second mandibular molars. The canals were instrumented at three different WLs: G-1, 1mm short of the major apical foramen; G0, at the major apical foramen; G+1, 1mm beyond the major apical foramen. The groups were assessed for changes in root canal volume and untouched wall area in the apical third. Groups G0 and G+1 were also compared for percentage of untouched walls at the apical foramen. One-way ANOVA (post hoc Tukey test) and Student's t-test adopted a 5% level of significance. Results: Root canal volumes (mm3) in the apical third were 22.86±10.46, 44.48±24.91, and 55.71±21.32 in G-1, G0 and G+1, respectively. G-1 volume following instrumentation increased significantly less than that of G0 or G+1 (P>.05); G0 did not differ from G+1. The percentage of untouched wall area in the apical third did not differ among the three groups (P>.05). G0 and G+1 did not differ regarding untouched walls in the major apical foramem walls. Conclusion: Extending the WL from 1mm short of the apical foramen to a point at and beyond the WL increases the apical third volume without increasing the prepared area. Untouched surface areas of the apical foramen were not modified by instrumentation at or beyond the foramen

Modified pulpotomy procedure in immature permanent teeth with apical periodontitis: a randomised controlled trial.

OBJECTIVES: The objective of this study was to evaluate the effectiveness of a modified pulpotomy (MP) procedure in immature permanent teeth with apical periodontitis (AP). DESIGN: Randomised controlled trial. SETTING: One public hospital in Shanghai, China PARTICIPANTS: A total of 33 teeth (31 patients) with a definitive diagnosis of AP with radiographic periapical radiolucency were recruited in this study. All the patients (teeth) completed the study accordingly. METHODS AND INTERVENTION: Patients were randomly assigned to either MP or apexification treatment groups and were followed up for 12 months. Clinical symptoms and complications were recorded, and parallel periapical radiographic images were used to measure changes in root length and apical diameter. Wilcoxon's rank sum test and Fisher's exact test were used to compare the clinical and radiographic outcomes between MP and apexification, and analysed with analysis of variance. MAIN OUTCOME MEASURE: The primary outcome was increase in root length at 12 months. The secondary outcomes included tooth survival, clinical success and decrease in apical diameter. RESULTS: MP group showed a significant increase in root length (10.05%±2.14% vs 1.16%±0.79%, p<0.05) at 12 months and a decrease in apical diameter (48.88%±10.42% vs 15.90%±8.88%, p<0.05) as compared with the apexification group. The tooth survival rate was 100%, and 90.91% (30/33) of teeth were asymptomatic with apical healing in both treatment groups (p>0.05). CONCLUSIONS: MP can be an option for treating immature permanent teeth with AP. MP showed better performance in terms of continued root maturation than apexification. MP and apexification achieved comparable outcomes with regard to the resolution of clinical symptoms and apical healing. TRIAL REGISTRATION NUMBER: ChiCTR-INR-17012169.

Comparison of apical debris extrusion of different generation nickel-titanium instrument systems.

Background and Aim: The aim of this study is to evaluate the apical debris extrusion amounts and preparation times of four different nickel-titanium systems with a similar cross-section design-Mtwo, RECIPROC, RECIPROC blue, and VDW.ROTATE. Materials and Methods: Eighty human mandibular central incisors were divided into four equal groups (n = 20). The test apparatus was inserted into an assembly that provided root canal temperature. Preparation times were recorded using a stopwatch, and the amount of extruded debris was collected in pre-weighed Eppendorf tubes. After drying, the net amount was determined by subtracting the previously measured Eppendorf tube weights from the total weight. Results: The Mtwo had the largest amount of debris, but there was no significant difference among the other groups. The VDW.ROTATE completed the preparation in a significantly shorter time than the RECIPROC blue and Mtwo. Conclusion: Compared to other files, the Mtwo sequence produced significantly more debris and required significantly more time to complete the whole root canal preparation.

Eficácia e importância da patência foraminal em casos de dentes despolpados e em dentes com vitalidade pulpar / Efficacy and importance of apical foramen patency in procedures involving pulpless teeth and teeth with vital pulps

A ciência endodôntica possui um vasto conhecimento e com esse conhecimento os seus inúmeros questionamentos. Algumas teorias e conceitos mudam constantemente e trazem à tona contradições e divergências clínicas no âmbito biológico e prático. A patência foraminal é uma prática que permite que um instrumento de pequeno calibre ultrapasse o forame apical, com o intuito de limpar passivamente e prevenir o acúmulo de detritos e inibir a proliferação de microorganismos que podem causar infecções pós tratamento endodôntico. Essa prática gera discussão interna entre especialistas da área, mas as vantagens da técnica são inúmeras, principalmente no que diz respeito aos casos de polpa necrosada. Casos como esse não são solucionados com sucesso sem a utilização da patência apical. Por outro lado, existem contradições em relação aos casos em que a polpa está viva. Esse trabalho tem como objetivo analisar as vantagens e desvantagens da patência apical, bem como, se os benefícios excedem os possíveis danos que ela pode trazer(AU)

Endodontic science has vast knowledge and with this knowledge its countless questions. Some theories and concepts are constantly changing and bring to light clinical contradictions and divergences in the biological and practical scope. Foraminal patency is a practice that allows a small-caliber instrument to go beyond the apical foramen, in order to passively clean and prevent the accumulation of debris in the region and inhibit the proliferation of microorganisms that can cause infections after endodontic treatment. This practice generates internal discussion among specialists in the field, but the advantages of the technique are numerous, especially with regard to cases of necrotic pulp. Cases like this are not successfully resolved without the use of apical patency. On the other hand, there are contradictions regarding the cases where the pulp is alive. This work aims to analyze the advantages and disadvantages of apical patency, as well as whether the benefits exceed the harm it can bring(AU)

Panoramic radiography and cone-beam computed tomography to measure distances between root apexes and anatomical structures / Radiografía panorámica y tomografía computarizada de haz cónico para medir distancias entre ápices radiculares y estructuras anatómicas

Aim: To compare the accuracy of the panoramic radiography with cone-beam computed tomography (CBCT) scans in measuring the distances between root apexes and the adjacent anatomical structures including the maxillary sinus and the mandibular canal. Material and Methods: A total of 200 CBCT scans (100 maxillary and 100 mandibular) from patients who also had corresponding panoramic radiography were selected. Linear measurements (in mm) presenting centralized image were made between the apexes of the maxillary teeth and the inferior wall of the maxillary sinus, and between the apexes of the mandibular teeth and the superior border of the mandibular canal by using specific software for panoramic radiography and the measurements on the coronal sections in CBCT scans. Data were submitted to inferential statistical analysis and Student's t-test for comparison between measurements. Results: CBCT scans were significantly more accurate than panoramic radiography to measure the distances between the apexes of the maxillary teeth and the inferior wall of the maxillary sinus (p<0.05) and between the apexes of the mandibular teeth and the superior border of the mandibular canal or mental foramen (p<0.05). Conclusion: CBCT scans present more accurate measurements than panoramic radiography.

Objetivo: Comparar la precisión de la radiografía panorámica con las exploraciones de la tomografía computarizada dental de haz en cónico (CBCT) para medir las distancias entre los vértices radiculares y las estructuras anatómicas adyacentes, incluidos el seno maxilar y el canal mandibular. Material y Métodos: Se seleccionaron un total de 200 tomografías CBCT (100 maxilares y 100 mandibulares) de pacientes que además tenían la correspondiente radiografía panorámica. Se realizaron mediciones lineales (en mm) que presentaban imagen centralizada entre los ápices de los dientes maxilares y la pared inferior del seno maxilar, y entre los ápices de los dientes mandibulares y el borde superior del canal mandibular mediante software específico para radiografía panorámica. y las mediciones en las secciones coronales en escaneos CBCT. Los datos se sometieron a análisis estadístico inferencial y prueba t de Student para comparación entre mediciones. Resultados: Las exploraciones CBCT fueron significativamente más precisas que la radiografía panorámica para medir las distancias entre los ápices de los dientes maxilares y la pared inferior del seno maxilar (p<0,05) y entre los ápices de los dientes mandibulares y el borde superior de los dientes mandibulares. canal o agujero mentoniano (p<0.05). Conclusión: Las exploraciones CBCT presentan mediciones más precisas que la radiografía panorámica.

Enhanced conservation of vital pulp and apical tissues by the application of crown rotation surgery for inversely impacted central incisors: A follow-up analysis of two patients over 4 years.

AIM: To describe a novel surgical method (crown rotation surgery) to manage inversely impacted central incisors with immature roots. METHODOLOGY: Two young patients each presented with an inversely impacted maxillary central incisor. To protect the apical tissues, the two impacted incisors were rotated downwards to a relatively normal position without extraction from their bony sockets. RESULTS: After crown rotation surgery, spontaneous eruption, continuous root development, and periodontal healing of the rotated incisors were observed. The pulp retained vitality and blood flow was normal. Moreover, there were no obvious signs of pulp canal obliteration (PCO), as indicated by Cone Beam Computed Tomography (CBCT) imaging. CONCLUSIONS: By optimising protection of the vital pulp and apical tissues, crown rotation surgery represents a minimally invasive, conservative, and practical surgical technique for treating inversely impacted incisors with developing roots. In contrast to existing surgical methods, crown rotation surgery may avoid certain complications, including PCO and abnormal or arrested root development. KEY LEARNING POINTS: By optimizing protection of the vital pulp and apical tissues, crown rotation surgery represents a minimally invasive, conservative and practical surgical technique for treating inversely impacted incisors with developing roots. In contrast to existing surgical methods, crown rotation surgery may avoid certain complications, including PCO and abnormal or arrested root development.