Retreatment Groups Research Articles

Quantitative Assessment of Apically Extruded Debris During Retreatment Procedures Using Three Nickel-Titanium Rotary Systems: An In Vitro Comparative Study

Objectives: Apical extrusion of debris can affect the success of endodontic treatments, and the specific performance of certain retreatment systems has not been studied yet. Therefore, the aim of this in vitro study was to quantitatively assess the amount of apically extruded debris produced during retreatment procedures using three rotary NiTi retreatment systems in mature non-resorbed straight roots. Methods: Thirty extracted permanent human teeth with single straight roots were selected. The root canals were prepared with the ProTaper Next system up to size 30 and obturated with gutta-percha and AH Plus sealer using the continuous wave of condensation technique. The samples were stored for 30 days and randomized by computer sequence into three retreatment groups (n = 10): (1) ProTaper Universal Retreatment; (2) HyFlex Remover; and (3) VDW.Rotate Retreatment. Apically extruded debris was collected in Eppendorf tubes and weighed with a microbalance (10−5 g) before and after retreatment procedure. As the data were not normally distributed, the Kruskal–Wallis test was applied for comparing data among groups, with an alpha level set at α = 0.05. Dunn’s test was considered for post-hoc analyses, if appropriate. Results: Hyflex Remover was associated with the highest amount of extruded debris (0.85 ± 0.82 mg), followed by VDW.Rotate Retreatment (0.78 ± 0.41 mg) and ProTaper Universal Retreatment (0.62 ± 0.28 mg). However, the differences were not statistically significant (p > 0.05). Conclusions: All the retreatment systems tested were associated with apical extrusion of debris in vitro, with no significant quantitative differences between them, suggesting that clinicians can choose a retreatment system with features appropriate to the specific clinical situation without risk of increasing the amount of apically extruded debris.

Does selective root canal retreatment preserve the tooth’s fracture resistance? An ex-vivo study

ObjectivesTo assess the tooth’s fracture resistance when submitted to a selective root canal retreatment compared to the conventional approach.Methods33 intact permanent mandibular first molars were selected according to specific criteria. After teeth mounting, the primary root canal treatment was conducted and followed by thermo-mechanical aging procedures to mimic a few clinical conditions. The specimens were randomly divided into three groups (n = 11); a control group in which intact teeth were used and two experimental groups according to the retreatment approach: conventional non-surgical retreatment (Conventional-NSR), and selective non-surgical retreatment (Selective-NSR). Later, the teeth were submitted to a final thermo-mechanical aging procedure and tested regarding their fracture resistance (static fracture test). The maximum load to fracture was recorded as were the types of failure modes (repairable or non-repairable fracture). A proper statistical analysis was conducted, considering a significance level of 5%.ResultsThe Conventional-NSR group showed a mean failure load of 867.7 ± 108.9 N while the Selective-NSR group had 1106.8 ± 159.8 N (P = 0.012). Both retreatment groups showed significantly lower results when compared to the control group. Additionally, the Conventional-NSR group showed higher proportions of non-repairable fractures (54.5%) when compared to both the Selective-NSR (36.4%) and control (18.2%) groups.ConclusionsSelective root canal retreatment preserved the tooth’s fracture resistance compared to the conventional retreatment approach.Clinical trial numberNon-applicable. Conducting the current experiment was limited to obtaining approval from the local Research Ethics Committee at the Faculty of Dentistry, Minia University (Committee No. 105, Registration No. 902, Date: 26/3/2024).

Five-Year Clinical Trial of the Low-Concentration Atropine for Myopia Progression (LAMP) Study: Phase 4 Report

PurposeTo evaluate (1) the long-term efficacy of low-concentration atropine over 5 years, (2) the proportion of children requiring retreatment and associated factors (3) the efficacy of pro re nata (PRN) retreatment using 0.05% atropine from year 3 to 5. DesignA randomized, double-masked extended trial. MethodsChildren aged 4–12 years originally from the Low-Concentration Atropine for Myopia Progression study were followed up for 5 years. During the third year, children in each group originally on 0.05%, 0.025%, and 0.01% atropine were randomized to continued treatment and treatment cessation. During years 4 and 5, all continued treatment subgroups were switched to 0.05% atropine for continued treatment, while all treatment cessation subgroups followed a PRN retreatment protocol to resume 0.05% atropine for children with myopic progressions of 0.5D or more over one year. Generalized estimating equations were used to compare the changes in spherical equivalent (SE) progression and axial length (AL) elongation among groups. Outcomes Measures(1) Changes in SE and AL over 5 years in different groups over 5 years; (2) Proportion of children who needed retreatment; (3) Changes in SE and AL in continued treatment and PRN retreatment groups from years 3 to 5. Results269 (82.5%) of 326 children from the third year completed 5 years of follow-up. Over 5 years, the cumulative mean SE progressions were –1.34±1.40D, –1.97±1.03D, and –2.34±1.71D for the continued treatment groups with initial 0.05%, 0.025%, and 0.01% atropine respectively (P=0.02). Similar trends were observed in AL elongation (P=0.01). Among the PRN retreatment group, 87.9%(94/107) of children needed retreatment. The proportion of retreatment across all studied concentrations is similar (P=0.76). The SE progressions for continued treatment and PRN retreatment groups from years 3 to 5 were – 0.97D±0.82D, and –1.00±0.74D (P=0.55), and the AL elongations were 0.51±0.34mm, and 0.49±0.32mm (P=0.84), respectively. ConclusionsOver 5 years, the continued 0.05% atropine treatment demonstrated good efficacy for myopia control. The majority of children needed to restart treatment after atropine cessation at year 3. Restarted treatment with 0.05% atropine achieved similar efficacy as continued treatment. Children should be considered for retreatment if myopia progresses after treatment cessation.

Factors Predicting the Need for Re-treatment After Laser Refractive Surgery in Patients With Mixed Astigmatism.

To identify risk factors that increase the likelihood of re-treatment following refractive surgery in patients with mixed astigmatism. This was a retrospective study including patients who underwent either laser in situ keratomileusis (LASIK) or photorefractive keratectomy (PRK) between 2000 and 2019 and had mixed astigmatism (spherical error of +0.50 D or greater and spherical equivalent of less than 0.00 diopters [D]). Patients were divided into two groups according to whether they underwent re-treatments during the study period. Overall, 785 eyes (785 patients) were included. In total, 5.2% of the eyes (n = 41) underwent re-treatment. The re-treatment group was more likely to have preoperative high astigmatism (80.5% vs 48.3%, P < .001), moderate to high hyperopia (36.6% vs 22.3%, P = .035), and to have undergone surgery earlier during the study period (P < .001). They were also more likely to have undergone surgery using the Wave-Light EX200 rather than the EX500 laser platform (Alcon Laboratories, Inc) (P < .001), have a treated optical zone of 6 mm rather than 6.5 mm (P < .001 for both), and their maximum ablation depth was greater (P < .001). There was no difference between the re-treatment and control groups regarding procedure type (PRK vs LASIK). Binary logistic regression found preoperative high astigmatism (odds ratio = 3.97, P < .001) and the type of laser platform used (EX200, odds ratio = 7.78, P < .001) as the only independent factors associated with re-treatment. Re-treatment rates following correction of mixed astigmatism were 5.2% over 20 years. Use of a sixth-generation laser platform significantly reduced the risk of re-treatment. Presence of high astigmatism is a significant risk factor for re-treatment. There was no difference in retreatment risk between PRK and LASIK. [J Refract Surg. 2024;40(2):e73-e78.].

Efficiency and complications in root canal retreatment using nickel titanium rotary file with continuous rotation, reciprocating, or adaptive motion in curved root canals: a laboratory investigation

BackgroundIt is currently unknown whether rotary file motion affects the best outcome of root canal retreatment. This experimental study compared the efficacy, efficiency, and complications of single-use NiTi rotary files using continuous rotation, reciprocating, and adaptive motions in root canal filling removal in curved root canals. Reciproc blue R25 was used with reciprocating motion (RB), VDW.ROTATE retreatment files with continuous rotation (VR), and ProTaper NEXT X2 with continuous rotation (PTNc) or adaptive motion (PTNa).MethodsForty mesial root canals of extracted mandibular first and second molars with an angle of curvature between 20°–40° and a radius of curvature between 5 and 10 mm were collected. The specimens were instrumented and obturated with gutta-percha and AH Plus sealer using the continuous wave of condensation technique. The specimens were randomly divided into 4 retreatment groups (n = 10), RB, VR, PTNc, and PTNa. The percentage of root canal filling removal in each group was analyzed using Micro-Computed Tomography (µCT). The motor running time, total time, root canal complication, and instrument complication were recorded and statistically analyzed (p-value < 0.05).ResultsThe pre-operative root canal curvature and root canal filling volume were comparable among groups. The percentage of root canal filling removal from the whole canal in the PTNc, RB, PTNa, and VR group was 98%, 96%, 95%, and 93%, respectively. A significant difference was observed between the PTNc and VR groups for the whole canal and the apical-third part. The motor running time and total time were significantly different between the groups. Instrument fracture was observed at 40% in the VR and 20% in the PTNa group, but none in the RB and PTNc groups.ConclusionsThe ProTaper NEXT X2 with continuous rotation and RB files can be used with high efficacy and efficiency in curved root canal retreatment. Continuous rotation is more efficacious and efficient than adaptive motion when using the NiTi rotary file. Single file retreatment can be used in small canals with high efficacy, cost-effectiveness, and less time consumption.

A Comparative Evaluation of Canal Transportation and Centering Ability with Three Different Retreatment File Systems– An In vitro CBCT Study

AIM: The study aimed to compare the canal transportation and centering ability of the three different retreatment file systems using cone-beam computed tomography imaging (CBCT).&#x0D; Methodology: Thirty three single-rooted, mandibular premolars were prepared up to ProTaper Gold size F2. Post intrumentation CBCT imaging was taken for all the samples. Obturation is done. The samples were randomly assigned to three different retreatment groups (n = 11), Group I: Pro Taper Universal retreatment kit, Group II: Mtwo R, and Group III: Xp endoshaper. Retreatment was done for all the samples using respective file systems followed by a Post-retreatment CBCT imaging. The two scans were compared both bucco-lingually and mesiodistally to determine canal transportation and centering ability at 3 mm, 6 mm, and 9 mm from the apex using DICOM Software. The results obtained were tabulated and statistically analyzed using One way Anova and Post hoc tukey test.&#x0D; Results: The mean canal transportation was least for Xp endoshaper (Group III). A Significant difference in canal transportation and centering ability was not observed at all three levels from the apex.&#x0D; Conclusion: Under in-vitro conditions, all three file systems have shown similar efficacy concerning canal transportation and centering ability. Based on mean values, canal transportation was higher for PTUR, followed by Mtwo R and Xp endo shaper in mesiodistal and buccolingual directions at 3, 6 and 9mm, and canal centering ability XP endo shaper stay centered followed by Mtwo R and PTUR in mesiodistal and buccolingual directions at 3, 6 and 9 mm.

Evaluation of the efficacy of TruNatomy, ProTaper retreatment, and RaCe file systems in retreatment of moderately curved mandibular molars: An in vitro study.

Endodontic retreatment is the first line of treatment in cases of failed primary endodontic treatment. Although associated with challenges such as incomplete removal of obturating material, increased clinical time, and extrusion of apical debris, endodontic retreatment still has considerable success rate in the general population. The aim of this study was to evaluate and compare the efficacy of TruNatomy, ProTaper retreatment, and RaCe file systems to remove the obturating material, time taken to remove the obturating material, and apical extrusion of debris using cone-beam computed tomography (CBCT). In vitro study. Forty-five moderately curved mesiobuccal roots of the mandibular molars were instrumented up to #25, 4% taper and obturated with bioceramic sealer and lateral compaction technique. Teeth were divided randomly into three groups (n = 15). Teeth were retreated with TruNatomy, ProTaper retreatment, and RaCe file systems, respectively. Preretreatment and postretreatment CBCT scans were recorded and percentage of obturating material removed was calculated. Time taken to remove the obturating material and apical extrusion of debris was noted. Descriptive statistics including percentage, mean, standard deviation, Tukey's post hoc test, Kruskal-Wallis test, and Mann-Whitney Post hoc test were used. The total time needed for the removal of obturating material was comparatively shorter in the RaCe group, followed by the ProTaper retreatment group and TruNatomy group (P < 0.001). TruNatomy files were significantly better in removing the obturating material than the ProTaper retreatment files (P = 0.04). Statically, no difference between RaCe and TruNatomy files was noted. Apically extruded debris was more in the TruNatomy group than in the RaCe and ProTaper retreatment groups (P = 0.01). All tested endodontic files were effective in removal of obturating material, although none could completely remove the filling material and no system could completely eliminate apical extrusion.

Effectiveness of endodontic retreatment using WaveOne Primary files in reciprocating and rotary motions.

This study evaluated the efficiency of WaveOne Primary files (Dentsply Sirona) for removing root canal fillings with 2 types of movement: reciprocating (RCP) and continuous counterclockwise rotation (CCR). Twenty mandibular incisors were prepared with a RCP instrument (25.08) and filled using the Tagger hybrid obturation technique. The teeth were retreated with a WaveOne Primary file and randomly allocated to 2 experimental retreatment groups (n = 10) according to movement type: RCP and CCR. The root canals were emptied of filling material in the first 3 steps of insertion, until reaching the working length. The timing of retreatment and procedure errors were recorded for all samples. The specimens were scanned before and after the retreatment procedure with micro-computed tomography to calculate the percentage and volume (mm3) of the residual filling material. The results were statistically evaluated using paired and independent t-tests, with a significance level set at 5%. No significant difference was found in the timing of filling removal between the groups, with a mean of 322 seconds (RCP) and 327 seconds (CCR) (p < 0.05). There were 6 instrument fractures: 1 in a RCP motion file and 5 in continuous rotation files. The volumes of residual filling material were similar (9.94% for RCP and 15.94% for CCR; p > 0.05). The WaveOne Primary files used in retreatment performed similarly in both RCP and CCR movements. Neither movement type completely removed the obturation material, but the RCP movement provided greater safety.

The Visceral-to-subcutaneous Adipose Tissue Area Ratio is Associated with Retreatment in Chronic Pancreatitis Patients with Pancreatolithiasis after Extracorporeal Shock Wave Lithotripsy.

Objective Extracorporeal shock wave lithotripsy (ESWL) has been used to treat pancreatolithiasis in patients with chronic pancreatitis (CP), but the high recurrence rate remains challenging. We therefore evaluated the association between body composition parameters and the prediction of retreatment after ESWL. Methods This study retrospectively evaluated 42 patients with CP who had been treated with ESWL between 2008 and 2019 in a single center. Body composition parameters were measured on pretreatment computed tomography images. Patients who underwent repeat ESWL were classified as the retreatment group. Results There were 13 (31.0%) and 29 (69.0%) patients in the retreatment and non-retreatment groups, respectively. The visceral-to-subcutaneous adipose tissue area ratio (VSR) of the retreatment group was significantly lower than that of the non-retreatment group (p=0.016). When divided by the median VSR, 10 of the 20 patients with a VSR of <0.85 underwent retreatment, whereas 3 of the 22 patients with a VSR of ≥0.85 underwent retreatment (p=0.019). According to a multivariate analysis, the VSR (p=0.010) and age (p=0.037) were independent factors associated with retreatment after ESWL. Conclusion This study showed that the VSR can predict the retreatment of patients with CP after ESWL.

Comparison in Retreatments between Bevacizumab and Ranibizumab Intravitreal Injections for Retinopathy of Prematurity: A Multicenter Study

To compare the types and dosages of anti-vascular endothelial growth factors (VEGFs) to ascertain whether specific dosages or types of injection were associated with retreatment in clinical practice in the United States. Multicenter, retrospective, consecutive series. Patients with retinopathy of prematurity (ROP) treated with anti-VEGF injections from 2007 to2021. Sixteen sites from the United States participated. Data collected included demographics, birth characteristics, examination findings, type and dose of anti-VEGF treatment, retreatment rates, and time to retreatment. Comparisons of retreatment rates between bevacizumab and ranibizumab intravitreal injections were made. Relative rate of retreatment between varying types of anti-VEGF therapy, including bevacizumab and ranibizumab, and the various dosages used for each. Data from 873 eyes of 661 patients (61% male and 39% female) were collected. After exclusion of 40 eyes treated with laser before anti-VEGF injection and 266 eyes re-treated with laser at or beyond 8 weeks after the initial anti-VEGF treatment, 567 eyes of 307 patients (63% male and 37% female) remained and were included in the primary analysis. There was no difference between the no retreatment and retreatment groups in terms of birthweight, gestational age, age at first injection, ROP stages, or number of involved clock hours. The retreatment group had a larger percentage of aggressive ROP (34% vs. 18%, P < 0.001) and greater percentage of zone 1 ROP (49 vs. 34%, P= 0.001) than the no retreatment group. Ranibizumab use was associated with a higher rate of retreatment than bevacizumab use (58% vs. 37%, P < 0.001), whereas the rate of retreatment was not associated with a specific dose of ranibizumab (R2= 0.67, P= 0.32). Meanwhile, lower doses of bevacizumab were associated with higher rates of retreatment compared with the higher doses (R2= 0.84, P= 0.01). There was a dose-specific trend with higher doses trending toward lower retreatments for bevacizumab. In a multicenter study of ROP patients initially treated with anti-VEGF therapy, ranibizumab and lower-dose bevacizumab use were associated with an increased rate of retreatment when compared with higher-dose bevacizumab. Proprietary or commercial disclosure may be found after the references.

Synergistic Effects and Ecological Responses of Combined In Situ Passivation and Macrophytes toward the Water Quality of a Macrophytes-Dominated Eutrophic Lake

Combined use of in situ passivation and macrophytes is a valuable technology that exerts remarkable effects on aquatic systems. However, the effectiveness and ecological functions of this combined technology for macrophytes-dominated eutrophic (MDE) lakes with organophosphorus-controlled internal phosphorus (P) loading were poorly understood. In this study, aquatic simulation experiments were performed to study the combination of La-modified materials (LMM; La-modified bentonite (LMB), and La/Al co-modified attapulgite (LAA)) with macrophytes (Myriophyllum verticillatum L. (MVL), Hydrilla verticillata (Linn. f.) royle (HVR), and Ceratophyllum demersum L. (CDL)) for the control of P mobility in the water column, and to investigate the passivator effects on the physiological characteristics of macrophytes. The mineralization of organophosphates (BD−Po, HCl−Po, and Res−Po) is an important factor for maintaining high internal P loadings and overlying water P concentrations in the experiments. Compared with individual treatment groups, the reduction of internal P release flux and porewater SRP concentrations was more obvious in the combined treatments. Moreover, the redox-sensitive P forms transformation is more pronounced in the surface sediments. In the LAA+M group, internal P release flux was reduced by 55% and 55% compared with individual passivators and macrophytes retreatment groups, respectively. In contrast, the LMB+M group decreased by 16% and 46%, respectively. Simultaneously, LMM had less effect on macrophytes traits compared with individual macrophytes group and enhanced the absorption of phosphate by macrophytes. The phosphate content of macrophytes in the LAA+M and LMB+M groups increased by 24% and 11%, respectively, in comparison with the individual macrophytes group. Results concluded that the combination of passivator and macrophytes enhanced the effect of ecological restoration and exerts a synergistic effect on internal P pollution with macrophytes.

Full counterclockwise rotary motion kinematics enhances the removal of gutta-percha and bioceramic sealer from root canals: A computed tomographic study.

Complete removal of gutta-percha and sealer is an important step during retreatment. The aim of this study was to assess the efficacy and time taken by full counterclockwise rotary motion of a reciprocating file in the removal of gutta-percha and BioRoot™ RCS bioceramic sealer. Thirty-six extracted human mandibular premolars were instrumented with Mtwo rotary files and obturated using lateral condensation technique with gutta-percha and BioRoot™ RCS bioceramic sealer. The teeth were divided into three retreatment groups (n = 12) based on the kinematics used: Group I, Mtwo retreatment (Mtwo-R) files; Group II, Reciproc files used in reciprocation mode (Reciproc-R); and Group III, Reciproc files used in full counterclockwise motion (Reciproc-CCW). The efficacy of gutta-percha and bioceramic sealer removal was assessed by volume of gutta-percha removed using cone-beam computed tomography and area of remaining gutta-percha and bioceramic sealer using ImageJ software after longitudinal sectioning. Statistical analysis was done by one-way analysis of variance test and Tukey's multiple post hoc tests. Reciproc-CCW motion was significantly efficient in the removal of gutta-percha and bioceramic sealer in comparison to Mtwo-R files and Reciproc-R. The time taken for gutta-percha and sealer removal was least for Reciproc-R (325.5 ± 101.68 seconds) and was statistically significant in comparison to the other groups. Within the limitations of the study, Reciproc-CCW was an effective method of removal of gutta-percha and bioceramic sealer during retreatment.

Efficacy of Rotary Retreatment Techniques Assisted with Passive Ultrasonic Activation of Resin Solvent in Removal of Gutta-percha with Epoxy Resin and MTA Based Root Canal Sealers: An In-vitro Study

Introduction: Endodontic retreatment is indicated in cases of failed primary endodontic treatment. The main goal of retreatment is to establish conditions that will enable the healing of the periapical tissue. Aim: To evaluate the efficacy of rotary retreatment with the ProTaper Universal Retreatment system supplemented with passive ultrasonic activation of solvent in retreatment of singlerooted mandibular premolar teeth obturated with gutta-percha and two different root canal sealers (AH Plus and MTA Fillapex). Materials and Methods: This in-vitro study was conducted in the Department of Conservative Dentistry and Endodontics at Mahatma Gandhi Mission’s Dental College and Hospital, Navi Mumbai, Maharashtra, India, from January 2019 to April 2019. Total 66 freshly extracted human single rooted mandibular premolars were used in this study. Root canal preparation was done using ProTaper Next rotary files. Teeth were decoronated to get a uniform length of 18 mm and were divided into three retreatment groups based on the technique used for retreatment. Group I included rotary retreatment, Group II involved rotary retreatment with solvent and paper point wicking, and Group III involved rotary retreatment with passive ultrasonic activation of solvent and paper point wicking. Based on the sealer used for obturation, teeth in each group were further divided into two subgroups, subgroup A with AH Plus sealer and subgroup B with MTA Fillapex sealer. Teeth were stored in an incubator for 30 days to allow sealer to set after which sectioning of the specimens was done buccolingually for examination under the stereomicroscope and photographed. Statistical analysis was done by using parametric Analysis of Variance (ANOVA) followed by Post-hoc tests and Unpaired t-test. Results: No statistically significant difference in percentage area of residual root canal filling material noted between the group I and II and when obturated with gutta-percha and AH Plus sealer (subgroup A) as p-value=0.215. Whereas, it revealed a statistically significant difference between the group I, II, and III when obturated with gutta-percha and MTA Fillapex sealer (subgroup B) as p-value&lt;0.001. Conclusion: Passive ultrasonic activation of solvent after guttapercha removal using ProTaper Universal rotary files could improve the quality of endodontic retreatment.

Characteristics of patients seeking orthodontic retreatment

BackgroundThe aim of this cross-sectional study was to investigate patients’ experiences with previous orthodontic treatment for those seeking retreatment, and their expectations and motivation for doing so. MethodsA total of 72 patients were invited to answer an anonymous questionnaire. Of these, 36 (13 men and 23 women, mean age 26.3 ± 5.8 years) were seeking retreatment (study group), and 36 (13 men and 23 women, mean age 25.5 ± 6.8 years) were seeking treatment for the first time (control group). Casts from both groups were assessed with the index of complexity, outcome, and need (ICON) score, to objectively determine the treatment need and complexity. Student`s t test for independent samples, and paired Student`s t test, were performed for comparisons between the retreatment and control groups, and between retreatment and previous treatment, respectively. ResultsThere was no statistically significant difference between retreatment patients` motivation for the previous treatment and motivation for the retreatment. However, the mean visual analog scale (VAS) scores for motivation differed significantly between the retreatment and control groups (73.8 ± 23.9 and 87.5 ± 14.5, respectively). The mean ICON score of the retreatment group was lower than that for the control group (25 ± 14 and 31 ± 16, respectively). ConclusionsPatients seeking retreatment were less motivated for treatment, and tooth irregularity was the chief reason for seeking treatment in both groups. Although an objective treatment need was not observed in the 2 groups, all of them had some occlusal traits that clinically justified the orthodontic treatment.

Nilotinib and Dasatinib Evoked Distinct Immune Effects during Tfr Phase of Each Discontinuation Trial

Nilotinib and Dasatinib Evoked Distinct Immune Effects during Tfr Phase of Each Discontinuation Trial

The Effect of Rotation Speed of XP-endo Shaper on Apically Extruded Debris During Endodontic Procedures: an In Vitro Study

The aim of this study was to evaluate the effect of using a higher rotation speed with the XP-endo Shaper (XPS) on apically extruded debris and operation time during endodontic treatment and retreatment procedures. Sixty mesial roots of mandibular first molar teeth were randomly assigned to four groups (Initial treatment groups: XPS used at 1000 or 3000rpm rotation speeds and Retreatment groups: XPS used at 1000 or 3000rpm rotation speeds). During the initial treatment and retreatment procedures preweighed eppendorf tubes were used to collect apically extruded debris, and the operation time was recorded in seconds. The extruded debris was quantified by subtracting the preinstrumentation from the postinstrumentation weight of the Eppendorf tubes. Data were analysed using two-way ANOVA at a significance level of 0.05. In all groups, the use of the XPS at 1000 or 3000rpm rotation speeds had no statistically significant effect on the amount of apically extruded debris (p&gt;0.05). The use of the XPS at a 3000rpm rotation speed significantly decreased the instrumentation time (p&lt;0.05). In summary, the use of the XPS at high rotation speeds in initial treatment and retreatment procedures did not have a significant effect on the amount of apically extruded debris but significantly decreased the operation time.

Clinical features and outcome of 15 patients with recurrent endometrial cancer or atypical endometrial hyperplasia received primary fertility-sparing therapy followed by hysterectomy

ObjectiveTo investigate the clinical features and outcome of recurrent endometrial cancer (EC) or atypical endometrial hyperplasia (AEH) patients who underwent hysterectomy after fertility-sparing therapy. MethodsClinical data was retrospectively collected for 15 recurrent endometrial cancer or atypical endometrial hyperplasia patients who underwent hysterectomy in six hospitals from 2003 to 2019. According to the indicators of hysterectomy, patients were divided into four groups: 7 patients who underwent direct hyesterectomy after the first relapse, 4 due to re-treatment failure, 1 after full term live birth, and 3 because of multiple recurrence. Clinical coexisting conditions, regimen and outcome of fertility-sparing therapy, pre- and post-operative pathological results, and prognosis were analyzed. Results(1) Fertility-spraring treatment was given to a total of 15 eligible patients, including 6 with EC and 9 with AEH. Median time interval from remission to recurrence was 12 months (range 3–92). Oral progestin-based medicine was the main fertility-sparing therapy in both primary treatment and re-treatment after recurrence. Six (6/8) patients received progestin combined with gonadotrophin releasing hormone agonist or metformin in three re-treatment groups. (2) Nine patients underwent hysterectomy and 6 staging surgery. Three patients had pathological upgrade after surgery. Five (5/10) EC patients had superficial myometrial invasion in postoperative pathology. All patients showed no evidence of disease in the median follow-up of 17 months (range 3–118). (3) Among seven patients who failed to re-treatment and had multiple recurrence, six were overweight/obesity and six had insulin resistance. Two of these patients had synchronous ovarian cancer in the postoperative pathology. ConclusionFor the patients with recurrent EC or AEH after primary fertility-sparing therapy, overweight/obesity and insulin resistance might be the risk factors for re-treatment failure. Hysterectomy is recommended when patients had re-treatment failure or multiple recurrence; and generally the prognosis is favorable.

Effectiveness of Glecaprevir/Pibrentasvir for Hepatitis C: Real-World Experience and Clinical Features of Retreatment Cases.

Glecaprevir/pibrentasvir (G/P) are direct-acting antivirals (DAAs) that achieve a high sustained virological response (SVR) rate for hepatitis C virus (HCV) infection. We investigated G/P effectiveness for HCV patients based on real-world experience and the clinical features of retreatment cases. HCV patients (n = 182) were compared for clinical features and outcomes between first treatment (n = 159) and retreatment (n = 23) G/P groups. Overall, 77 patients (42.3%) were male, the median age was 68 years, and 86/66/1/4 cases had genotype 1/2/1 + 2/3, respectively. An SVR was achieved in 97.8% (178/182) of cases by intention-to-treat analysis and 99.4% (178/179) of cases by per-protocol analysis. There were no remarkable differences between the first treatment and retreatment groups for male (42.8% vs. 39.1%, p = 0.70), median age (68 vs. 68 years, p = 0.36), prior hepatocellular carcinoma (5.8% vs. 8.7%, p = 0.59), or the fibrosis markers AST-to-platelet ratio index (APRI) (0.5 vs. 0.5, p = 0.80) and fibrosis-4 (FIB-4) index (2.2 vs. 2.6, p = 0.59). The retreatment group had a significantly more frequent history of interferon treatment (12.3% vs. 52.2%, p < 0.01) and the Y93H mutation (25.0% vs. 64.7%, p = 0.02). The number of retreatment patients who had experienced 3, 2, and 1 DAA treatment failures was 1, 3, and 19, respectively, all of whom ultimately achieved an SVR by G/P treatment. In conclusion, G/P was effective and safe for both HCV first treatment and retreatment cases despite the retreatment group having specific resistance mutations for other prior DAAs. As G/P treatment failure has been reported for P32 deletions, clinicians should consider resistance mutations during DAA selection.

Detrimental Effect of Delayed Re-treatment of Active Disease on Outcomes in Neovascular Age-Related Macular Degeneration: The RAMPS Study

To assess the impact of delaying anti-vascular endothelial growth factor (VEGF) treatment of active disease at any point during a patient's treatment journey on clinical outcomes in a real-world cohort of patients with neovascular age-related macular degeneration (nAMD). Longitudinal cohort study. Consecutive treatment-naive nAMD eyes commencing anti-VEGF monotherapy (bevacizumab, ranibizumab, or aflibercept) from January 2014 from a tertiary eye center in Singapore. We conducted a real-world study using registry data comparing delayed re-treatment (defined as not receiving treatment at 2 or more monitoring visits when disease was graded as active) versus timely re-treatment (defined as receiving treatment when disease was active). The primary outcome was the change in visual acuity (VA) in the timely and delayed re-treatment groups at 12 months. Data from 286 eyes were included and categorized into the timely (188 [66%]) or the delayed (98 ([34%]) group. The mean numbers of anti-VEGF injections over 12 months were similar: 5.6 (standard deviation [SD], 2.9) versus 4.9 (SD, 3.2; P= 0.11) for the timely and delayed groups, respectively. Timely treated patients showed larger gains in VA (6.4 letters [SD, 8.1 letters] vs. 1.2 letters [SD, 5.3 letters; P= 0.04), a higher proportion with VA of 6/12 or better (30% vs. 8%; P= 0.01), and greater reduction in OCT-measured central subfield thickness (135 μm [SD, 154 μm] vs. 87.8 μm [SD, 129 μm]; P= 0.04) at 12 months. A longer delay between detection of active disease and re-treatment was associated with poorer vision outcomes (0.02-letter decrease/day; P= 0.03; R2= 0.29). Although it has been established that adequate numbers of injections are required for favorable outcomes, timely re-treatment of active disease also is important. This should be emphasized to patients to ensure optimal outcomes in real-world clinical settings.

Outcome of retreatment for recurrent saccular cerebral aneurysms: a propensity score-matched analysis.

Although endovascular or surgical treatment has been performed for preventing the rupture of saccular cerebral aneurysms (sCA), in some patients, the aneurysms may recur and require retreatment. We aimed to investigate the clinical and radiological outcomes of treating recurrent sCA. We retrospectively evaluated the data of 52 patients with 60 recurrent sCAs who were retreated and 1534 patients with 1817 sCAs who received initial treatment. The primary outcome was a recurrence of the aneurysm. Secondary outcomes were an additional treatment, rupture after treatment, and a neurological worsening, which was defined as an increase of 1 or more scores using the modified Rankin Scale at 12-month. Safety outcomes included postoperative ischemic and hemorrhagic complications. We compiled the 120 (60 each) propensity score-matched cohort based on a propensity score for the treatment of recurrent sCA. In the propensity score-matched cohort, recurrence after treatment was observed in 25% and 6.7% of cases in the retreatment and initial treatment groups, respectively. The odds ratio of recurrence after treatment was 4.7 (95% CI, 1.4-15; P = 0.011). The secondary and safety outcomes were not significantly different between the two groups. This study showed that the treatment of recurrent sCA was a risk factor for recurrence after treatment but not for additional treatment, rupture after treatment, or neurological worsening. Although decision-making regarding the treatment varies depending on the institutional protocols and personal experience of the physicians, endovascular or surgical retreatment could be performed without hesitation.