Full Root Research Articles

Endodontic characteristics of mandibular premolar with dens evaginatus: a retrospective study.

This study aimed to investigate the endodontic characteristics of mandibular premolars with dens evaginatus (DE) that require endodontic treatment. Patients who underwent endodontic treatment were enrolled. The inclusion criteria were patients who underwent root canal treatment in the lower permanent teeth with DE and were followed up for at least 1 year. Preoperative clinical and radiographic variables were obtained. The frequency distribution of the preoperative variables was compared using the χ2 or Fisher's exact tests. The significance of the change in periapical health index (PAI) and root development stages before and after treatment was examined using the Wilcoxon signed-rank test. A total of 150 teeth of 134 patients with an average age of 15.3 years were included. The percentage distribution comparison of the preoperative variables and obturation techniques revealed significant differences in pulpal and periapical diagnosis, and percussion, and especially regarding age, root development stage, and PAI. Age was the only statistically significant preoperative variable associated with root growth (p < 0.05). Approximately, 60% of DEs requiring endodontic treatment had immature roots. Age being the most significant predisposing factor, early treatment provides the greatest opportunity for full root development.

Adaptation of regenerant plants representing the genus Hydrangea L. to non-sterile conditions using a hydroponic system

The adaptation of regenerant plants to ex vitro conditions constitutes the final stage of clonal micropropagation for hydrangea. The study used the AirCube Ebb &amp; Flow hydroponic system that periodically floods the plant roots with a nutrient-rich solution. The study examined the effect of three different substrates on the establishment of regenerant plants: agroperlite, coconut substrate, and mineral wool. The establishment of microshoots with the use of the hydroponic system was found to average 85 %. Agroperlite proved to be the most effective substrate for the adaptation of regenerant plants: the average plant establishment amounted to 90 %; the use of mineral wool was shown to be the least effective (81 %). A greater number of plants with full root system development after 15 days of adaptation was noted with the use of agroperlite and coconut substrate. Of all the studied substrates, agroperlite was more effective for root system development (average root length of 5.9 cm), with the coconut substrate being slightly inferior (average root length of 5.4 cm); the use of mineral wool was the least effective (average length of 2.9 cm). The greatest average plant height at day 30 of cultivation was observed in H. arborescens varieties (8.61 cm), while the lowest was noted in the varieties of H. paniculata (4.02 cm). The use of a hydroponic system in the adaptation of regenerant plants was proved to provide a means to obtain the planting material of hydrangea with a developed above-ground part and root system in 30 days.

Long-term outcome after the Ross procedure in 173 adults with up to 25 years of follow-up.

The potential risk of autograft dilatation and homograft stenosis after the Ross procedure mandates lifelong follow-up. This retrospective cohort study aimed to determine long-term outcome of the Ross procedure, investigating autograft and homograft failure patterns leading to reintervention. All adults who underwent the Ross procedure between 1991 and 2018 at the University Hospitals Leuven were included, with follow-up data collected retrospectively. Autograft implantation was performed using the full root replacement technique. The primary end-point was long-term survival. Secondary end-points were survival free from any reintervention, autograft or homograft reintervention-free survival, and evolution of autograft diameter, homograft gradient and aortic regurgitation grade over time. A total of 173 adult patients (66% male) with a median age of 32 years (range 18-58 years) were included. External support at both the annulus and sinotubular junction was used in 38.7% (67/173). Median follow-up duration was 11.1 years (IQR, 6.4-15.9; 2065 patient-years) with 95% follow-up completeness. There was one (0.6%) perioperative death. Kaplan-Meier estimate for 15-year survival was 91.1% and Ross-related reintervention-free survival was 75.7% (autograft: 83.5%, homograft: 85%). Regression analyses demonstrated progressive neoaortic root dilatation (0.56 mm/year) and increase in homograft gradient (0.72 mmHg/year). The Ross procedure has the potential to offer excellent long-term survival and reintervention-free survival. These long-term data further confirm that the Ross procedure is a suitable option in young adults with aortic valve disease which should be considered on an individual basis.

Root-to-shoot signaling positively mediates source-sink relation in late growth stages in diploid and tetraploid wheat

Non-hydraulic root source signaling (nHRS) is a unique positive response to soil drying in the regulation of plant growth and development. However, it is unclear how the nHRS mediates the tradeoff between source and sink at the late growth stages and its adaptive mechanisms in primitive wheat. To address this issue, a root-splitting design was made by inserting solid partition in the middle of the pot culture to induce the occurrence of nHRS using four wheat cultivars (MO1 and MO4, diploid; DM22 and DM31, tetraploid) as materials. Three water treatments were designed as 1) both halves watered (CK), 2) holistic root system watered then droughted (FS), 3) one-half of the root system watered and half droughted (PS). FS and PS were designed to compare the role of the full root system and split root system to induce nHRS. Leaves samples were collected during booting and anthesis to compare the role of nHRS at both growth stages. The data indicated that under PS treatment, ABA concentration was significantly higher than FS and CK, demonstrating the induction of nHRS in split root design and nHRS decreased cytokinin (ZR) levels, particularly in the PS treatment. Soluble sugar and proline accumulation were higher in the anthesis stage as compared to the booting stage. POD activity was higher at anthesis, while CAT was higher at the booting stage. Increased ABA (nHRS) correlated with source-sink relationships and metabolic rate (i.e., leaf) connecting other stress signals. Biomass density showed superior resource acquisition and utilization capabilities in both FS and PS treatment as compared to CK in all plants. Our findings indicate that nHRS-induced alterations in phytohormones and their effect on source-sink relations were allied with the growth stages in primitive wheat.

Coronally advanced flap with and without connective tissue graft in root coverage procedure: A Case Series

Objective: This paper aims to report the outcome of the coronally advanced flap with and without connective tissue graft in the root coverage procedure. We intend to explain the importance of connective tissue graft in coronally advanced flap surgery. Methods: Two patients with gingival recession required surgical intervention to get root coverage and improve aesthetics. Both patients were treated with a coronally advanced flap. We combined the coronally advanced flap with a connective tissue graft for the first patient's maxillary left second incisor and canine; meanwhile, we only did the coronally advanced flap for the second patient's maxillary right canine and first premolar. Results: Surgical intervention was done for both patients with good results. For the first patient with a connective tissue graft, we noticed increased thickness on the keratinized gingiva and gained 1 mm of root coverage. Meanwhile, we got full root coverage for the second patient. In this article, a patient with a connective tissue graft was observed for six months, and a patient without a connective tissue graft was observed for two years. In both cases, we noticed stable and good results. Conclusions: Coronally advanced flap procedure can be a reliable treatent for root coverage in the tooth with gingival recession. An additional connective tissue graft combined with a coronally advanced flap can increase keratinized tissue thickness.

Should we operate on patients with acute type A aortic dissection who present with cardiopulmonary resuscitation?

Acute aortic dissection type A (AADA) is a life-threatening medical emergency. Emergent surgical repair is the gold standard but mortality remains high. Mortality is even higher in patients who arrive at the hospital in poor condition, especially after cardiopulmonary resuscitation (CPR). This study was designed to analyse the outcome of patients who underwent surgery for AADA and who require preoperative CPR. Between 2000 and 2023, 810 patients underwent emergent surgery for AADA at our centre. Of these, 63 had preoperative CPR. We performed a retrospective analysis with follow-up. Mean age was 64 ± 13 years and 37 (59%) patients were male. Further, 50 (79%) patients had preoperative intubation, and 54 (86%) had pericardial effusion. Twenty-four (38%) patients had out-of-hospital CPR, 19 (30%) required CPR in hospital and 20 (32%) needed CPR in the operating room. Successful CPR with return of spontaneous circulation was achieved in 41 (65%) patients, and 22 (35%) underwent emergent surgery under ongoing CPR. The median time of CPR was 10 (interquartile range 12) min, and the median time from onset of symptoms to start of the operation was 5.5 (interquartile range 4.8) h. The majority of patients underwent ascending aortic replacement with hemiarch repair (n = 37, 59%). Further, 26 (41%) patients underwent full root replacement. Another 15 (24%) patients underwent total arch repair with or without (frozen) elephant trunk repair. Postoperative stroke was present in 8 (13%) patients. The 30-day mortality was 29 (46%). The 30-day mortality of patients with preoperative intubation was not significantly higher (n = 15/28, 54%, P = 0.446). The 1-, 5- and 10-year survival rates of the entire group were 42, 39 and 36%. Early mortality for patients undergoing surgery for AADA with preoperative CPR is extremely high (almost 50%). However, this means that also ∼50% of patients benefit from surgery despite poor preoperative prognosis. Patients with preoperative intubation after CPR and unknown neurological condition should also undergo surgery. Patients who survive the initial operation for AADA have acceptable long-term survival. Emergent surgery should be offered for all patients with AADA regardless of the preoperative condition, even after CPR.

The Management of Hyperplastic Pulpitis in Immature Permanent Molar Using Vital Pulp Therapy: A Case Report with 12 Months Follow‐Up

Hyperplastic pulpitis is an irreversible type of pulpitis that primarily affects young patients. It occurs when an inflamed pulp becomes exposed due to factors such as dental caries, dental trauma, or other causes. Root canal treatment is commonly employed to manage hyperplastic pulpitis. However, vital pulp therapy can be considered as a less invasive option. The main objective of this treatment is to preserve the vitality and functionality of the remaining pulp tissue. This case report discusses the potential management of hyperplastic pulpitis in an immature molar using vital pulp therapy instead of a full root canal treatment. The report includes clinical and radiographic follow‐up at six and twelve months.

Reoperations after Ross procedure: a retrospective study

Aim. To analyze the immediate outcomes of reinterventions after Ross procedure.Material and methods. From April 2009 to December 2022, 224 Ross operations in adults were performed at the Federal Center for Cardiovascular Surgery. The retrospective study included 17 patients who required repeated interventions (14 men/3 women). The mean age of the patients was 38±11 years, with a minimum age of 21 and a maximum of 54 years. A history of infective endocarditis was revealed in 4 (23,5%) patients, hypertension — in 3 (17,6%) patients. Of the 17 included patients, 15 patients underwent the classic Ross operation ("full root replacement"), while 2 — a modified technique (1 — wrapping with aorta, 1 — wrapping with a Dacron graft). Annulus enhancement was previously performed in 3 patients.Results. Interventions on the pulmonary autograft and homograft were performed in 16 and 4 cases, respectively. The main indication for pulmonary autograft intervention was aortic regurgitation in 15 cases, and neoaortic aneurysm in 14 cases. In 3 patients, there was pulmonary homograft stenosis, while in 1 case — thrombosis. Two patients required interventions on other valves: 1 — mitral valve stenosis, 1 — severe tricuspid regurgitation. Mean reoperation, cardiopulmonary bypass and myocardial ischemia time were 289±62, 126±35 and 98±22 min, respectively. Combined interventions were performed in 6 cases. David valve-sparing procedure was performed in 9 patients, Bentall-de Bono technique — in 3, aortic valve repair — in 2, mechanical aortic valve replacement — in 2, supracoronary ascending aorta replacement — in 2, pulmonary homograft replacement — in 2, pulmonary homograft thrombectomy — in 1, pulmonary homograft repair — in 1 patient, mitral valve replacement — in 1 patient, tricuspid valve repair — in 1 patient. One patient required resternotomy for bleeding. There were no postoperative complications (perioperative myocardial infarction, acute kidney injury, stroke, sternal infection, cardiac tamponade) and deaths. The median length of stay in intensive care unit was 21 [16-23] hours.Conclusion. Reoperations after the Ross procedure may be required for different pathologies, but all can be performed surgically with a high safety in experienced operator.

Clinical and Radiographic Outcomes of Mineral Trioxide Aggregate Pulpotomies in Vital Permanent Teeth with Carious Pulp Exposure: A Pioneering Retrospective Study.

Vital partial pulpotomy (PP) or cervical pulpotomy (CP) in carious pulp-exposed permanent teeth preserves tooth vitality, promotes pulp healing, decreases treatment costs, and shortens treatment duration, which is a significant factor in treating noncooperative children. The aim of this retrospective study was to compare clinical and radiographic outcomes of partial and CP in vital carious-exposed permanent teeth. All vital permanent teeth with carious pulp exposure, treated by pulpotomy using mineral trioxide aggregate (MTA) during 2017-2019, by two operators in one dental center, were included in the study. Around 118 permanent teeth in 97 children and adolescents (mean age 10.9 years) were evaluated 6-57 months postoperatively. The total success rates of CP and PP were 82.5 and 80.8%, respectively (p = nonsignificant). The only factor that significantly affected the success rate was the presence of preoperative periapical pathology. Teeth without such pathology showed an 87.3% success rate compared to 74.1 and 58.3% in teeth with preoperative enlarged periodontal ligament (PDL) or with periapical radiolucency, respectively (p = 0.0301). Demographic variables, maturation state of the tooth, type of tooth (incisor, premolar, molar), postoperative variables, such as the presence of radiographic dentinal bridge, partial or full obliteration of the pulp during the follow-up period, and the integrity of the final restoration during the recall examinations did not affect the success rate of the treatment. Partial and CP in vital permanent teeth with carious pulp exposure in children and adolescents might be a reliable alternative to full root canal treatment (RCT). Yoshpe M, Kaufman AY, Lin S, et al. Clinical and Radiographic Outcomes of Mineral Trioxide Aggregate Pulpotomies in Vital Permanent Teeth with Carious Pulp Exposure: A Pioneering Retrospective Study. Int J Clin Pediatr Dent 2023;16(4):555-559.

Apexogenesis and Apexification - Review

The role of dental pulp in the development of the teeth. Young patients with infected or damaged tooth pulp still present a challenge among practitioners due to the degree of tooth development, more specifically the permanent teeth that have not completed their root development. At the time of eruption, only two thirds of the tooth root is developed. If there is a disruption of pulp vitality before the full root development, the root growth and dentin formation stop, resulting in reverse-tapered or flared roots and an opened apex, which will make the future root canal treatment difficult. In these cases, we can find teeth with short roots, very thin walls and an inadequate crown-root ratio. The thing root walls increase the risk of fracture. We currently have several therapies available to treat these teeth, which we will discuss further on.

Video-assisted thoracoscopic redo sternotomy for primary dysfunction of the aortic root homograft: a case report

Adhesion in the anterior mediastinum following previous heart surgeries is a predictor of fatal trauma of the heart chambers, large vessels and lungs during redo cardiac procedures. The approaches used to prevent such complications have evolved over the past decades, but the need for their improvement remains. Annual increase in heart surgeries, coupled with the phenomenon of “aging population” in economically developed countries, predetermines the growth of redo cardiac surgical procedures. An important role in this process is also played by the recent more active use of various biological implants (for example, bioprosthetic heart valves), which makes the search for new technologies for safe redo sternotomy even more urgent.The publication presents a case of redo surgery in a patient with primary degeneration of the homograft in the aortic root position implanted 13 years ago for aortic stenosis using the Full Root technique. The original technique applied (Method for endoscopic prevention of traumatisation of cardiac, lung and major vessels of anterior mediastenum accompanying repeated cardiosurgical operations. Patent No. RU 2726605 C1) provides for a combination of minimally invasive and classic surgical approaches. Total adhesiolysis of the anterior mediastinum was performed thoracoscopically: the posterior surface of the sternum and the cartilaginous part of the ribs were completely freed from adhesions with the right ventricle, the aorta, lungs and innominate vein. The redo sternotomy was made using a standard electric saw under direct visual control and protection of the right ventricle and the ascending aorta with endoscopic retractors. The risk of surgical trauma of the anterior mediastinum organs was fully eliminated and the intraoperative blood loss was comparable to a traditional sternotomy approach. Received 27 January 2022. Revised 23 April 2022. Accepted 20 May 2022. Informed consent: The patient’s informed consent to use the records for medical purposes is obtained. Funding: The study did not have sponsorship. Conflict of interest: Authors declare no conflict of interest. Contribution of the authorsLiterature review: S.A. Petko, V.A. Popov, E.S. MalyshenkoDrafting the article: E.S. Malyshenko, S.A. PetkoCritical revision of the article: E.S. Malyshenko, V.A. Popov, A.Sh. RevishviliSurgical treatment: E.S. Malyshenko, M.G. Gasangusenov, V.A. PopovFinal approval of the version to be published: E.S. Malyshenko, S.A. Petko, V.A. Popov, M.G. Gasangusenov, A.Sh. Revishvili

Frozen elephant trunk in acute aortic type a dissection: risk analysis of concomitant root replacement.

To analyse whether full root replacement increases perioperative risks in patients who undergo frozen elephant trunk for acute aortic dissection. Between March 2013 and December 2019, 115 patients underwent emergency frozen elephant trunk for acute dissection. Patients without root replacement were assigned to group A, while patients with concomitant full root replacement to group B. Mean age was 50.8 (12.5) years and 85 (73.9%) patients were male. Preoperative malperfusion was present in 49 (42.6%) patients. In group B, 27 (41.5%) patients received composite root replacement and 38 (33.0%) aortic valve-sparing David procedure. Cardiopulmonary-bypass and cross-clamp times were 252.5 (208.5-293.0) and 96.0 (40.5-148.0) min in group A, and 310.0 (274.0-346.5) and 121.0 (89.0-182.0) in group B (P < 0.001). Continuous myocardial perfusion was used in 40 (80.0%) patients of group A and 59 (90.8%) of group B (P = 0.098). Disabling stroke was present in 10 (20.0%) patients in group A and 12 (18.5%) in group B (P = 0.835). Thirty-day mortality was 12.0% (n = 6) in group A and 9.2% (n = 6) in group B (P = 0.630). The 1- and 5-year survival rates were 80% and 62% in group A, and 81% and 79% in group B. Logistic regression analysis identified age (odds ratio = 1.117, 95% confidence interval = 1.004-1.242, P = 0.041), cardiopulmonary-bypass time (odds ratio = 1.012, 95% confidence interval = 1.001-1.022, P = 0.029) and abdominal malperfusion (odds ratio = 17.394, 95% confidence interval = 2.030-149.013, P = 0.009) to be associated with 30-day mortality. Full root replacement does not increase the perioperative risk in patients who undergo frozen elephant trunk for acute dissection. Careful patient selection is important for such complex procedures. Continuous myocardial perfusion can help reducing the risk for intraoperative complications during such complex operations.

Comparison of Cutting Efficiency and Safety of 10/0.04 RaCe and Mtwo Rotary File Systems in Reaching the Full Root Canal Working Length: An In Vitro Study

Introduction: Both RaCe and Mtwo rotary systems introduced the 10/0.04 file as the first file used in the root canal (Glide path). This study aims to compare different factors of both the rotary systems, including cutting efficacy, file fracture, topography changes of files, and changes of the root canal. Materials and Methods: In this laboratory study, 12 RaCe and 12 Mtwo files were prepared and tested on 24 resin blocks with 30° curvature. The time to reach the working length was recorded. Topographical changes of the files have been observed with a stereomicroscope if needed. Changes in resin blocks were measured by photographing and using Photoshop software. Data were analyzed through an independent two-sample t test and likelihood-ratio chi-squared test. Results: Time to reach the working length was significantly lower in the RaCe group than in the Mtwo group (3.57 ± 0.56 s vs. 10.33 ± 2.25 s, P < 0.001). File fracture did not occur in any of the two rotary systems. Topographical changes of the files in RaCe group were also less than the Mtwo group (P = 0.032). Conclusion: The RaCe file is faster in reaching the working length. Both files are safe and do not cause drastic changes in the root canal.

Potassium-Induced Drought Tolerance of Potato by Improving Morpho-Physiological and Biochemical Attributes

Potato (Solanum tuberosum) is the third and fourth most important tuberous crop in terms of human consumption and production, respectively. However, its growth and development are affected by drought, which is an emerging threat to agriculture especially in arid and semiarid areas. Potassium (K) is a well-known macronutrient that improves the performance of crops under drought. Therefore, the present study was enacted with the aim of evaluating the impact of K fertilizer on potato crop growth, productivity, and drought tolerance under full root irrigation (FRI) and partial root irrigation (PRI) conditions. Two potato cultivars (Lady Rosetta and Hermes) were grown under normal field conditions followed by FRI and PRI applications. Potassium sulfate was applied in three doses (T0 = 50 kg·ha−1, T1 = 75 kg·ha−1, and T2 = 100 kg·ha−1). The experiment was laid out under randomized complete block design (RCBD) with split plot arrangement. The main plot was allocated to irrigation, along with a subplot to potassium and a sub-subplot to potato cultivars. The results indicated that K application significantly improved the plant growth and yield by exhibiting better performance in morpho-physiological and biochemical attributes under FRI and PRI conditions; however, a more remarkable change was noticed under PRI compared with FRI. K application alleviated drought stress regardless of cultivars. This study suggests that K application at the rate of 100 kg·ha−1 is an effective approach for inducing drought tolerance in potato crops.

Freestyle Aortic Bioprostheses in Patients 60 Years old and Younger

Evaluate outcomes of the Freestyle stentless aortic bioprosthesis in patients 60 years old and younger. All patients, 60 years old and younger, between January 1, 1998 to December 31, 2015 who underwent implantation of a Freestyle aortic valve at a single institution were reviewed. Medical records and telephone interviews were utilized for data collection. 515 patients were identified with an average age of 51.3 years. Mean follow up was 11.1 years. 225 full root replacements and 290 subcoronary implants were performed. Overall survival, including patients with concomitant procedures, at 15 years was 63.7% (95% CI 58.3-68.5). Isolated subcoronary implants (58%,167/290) had a 15-year survival of 71.6% (95% CI 62.6-78.7) vs 78.4% (95% CI 69.7, 84.9) for isolated root replacements (63%,141/225) which was not statistically significant (P=0.397). No significant difference in operative SVD at 15 years occurred between full root replacements 37.6% (95% CI 27.2-50.2) vs subcoronary implants 39.4% (95% CI31.1, 49.0). 110 patients required reoperation solely for intrinsic SVD. 93% (102/110) failed due to aortic insufficiency. Of reoperative interventions for SVD, 37% (41/110) of patients required urgent reoperation and 4.5% (5/110) required emergent reoperation. Pseudoaneurysms developed in six of the full root replacements. Freestyle aortic valves have a high rate of acute failure requiring urgent or emergent reintervention in patients 60 years old and younger. This has led our group to shift practice away from their implantation.

Effects of drought stress on root morphology and spatial distribution of soybean and adzuki bean

Due to global climate change, Korea is facing severe droughts that affect the planting and early vegetative periods of upland crops. Soybean and adzuki bean are important legume crops in Korea, so it is critical to understand their adaptations to water stress. This study investigated the changes in root morphological properties in soybean and adzuki bean and quantified the findings using fractal analysis. The experiment was performed at the National Institute of Crop Science in Miryang, Korea. Soybeans and adzuki beans were planted in test boxes and grown for 30 days. The boxes were filled with bed soil with various soil moisture treatments. Root images were obtained and scanned every two days, and the root properties were characterized by root length, depth and surface area, number of roots, and fractal parameters (fractal dimension and lacunarity). Root depth, length and surface area and the number of roots increased in both crops as the soil moisture content increased. The fractal dimension and lacunarity values increased as the soil moisture content increased. These results indicated that the greater the soil moisture, the more heterogeneous the root structure. Correlation analysis of the morphological properties and fractal parameters indicated that soybean and adzuki bean had different root structure developments. Both soybean and adzuki bean were sensitive to the amount of soil moisture in the early vegetative stage. Soybean required a soil moisture content greater than 70% of the field capacity to develop a full root structure, while adzuki bean required 100% of the field capacity. These results would be useful in understanding the responses of soybean and adzuki bean to water stress and managing irrigation during cultivation.

Fabrication of Vascularized DPSC Constructs for Efficient Pulp Regeneration

Dental pulp regeneration is a promising approach to restore the vitality of necrotic teeth. We have previously reported the fabrication of scaffold-free cell constructs containing only dental pulp stem cells (DPSCs) and their ability to form pulp-like tissue in the pulpless tooth. However, the DPSC construct could not build pulp-like tissue with a full root length because it is difficult to induce blood vessels from a small root canal foramen. Therefore, we hypothesized that vascular structure could be preformed in the DPSC construct by employing endothelial differentiation capability of DPSCs, and vascularized constructs might facilitate dental pulp regeneration in the pulpless tooth. In this study, vascularized DPSC constructs were fabricated by inducing endothelial differentiation, and then we investigated the behavior of differentiated DPSCs, the internal structure of cell constructs, and their pulp regenerative ability in vivo. We observed that DPSCs positive for CD31 and von Willebrand factor were localized at the outer layer of constructs and formed a reticulated lumen structure. The cells constituting the outer layer of the construct expressed endothelial differentiation markers at higher levels than cells in the inner part. These results indicated that DPSCs in the outer layer differentiated into endothelial cells and formed vascular-like structures in the cell construct. Next, a vascularized DPSC construct was transplanted into the human pulpless tooth that was implanted into immunodeficient mice in the subcutaneous space. After 6 wk of implantation, the vascularized construct formed pulp-like tissues with higher density of human CD31-positive blood vessels when compared with specimens implanted with a DPSC construct without prevascularization. These results suggest that the vascular structure formed in the DPSC construct facilitated the blood supply and enhanced pulp regeneration. This study demonstrates that a vascularized DPSC construct is a prospective biomaterial as an implant for novel dental pulp regeneration.

Formin-mediated bridging of cell wall, plasma membrane, and cytoskeleton in symbiotic infections of Medicago truncatula

SummaryLegumes have maintained the ability to associate with rhizobia to sustain the nitrogen-fixing root nodule symbiosis (RNS). In Medicago truncatula, the Nod factor (NF)-dependent intracellular root colonization by Sinorhizobium meliloti initiates from young, growing root hairs. They form rhizobial traps by physically curling around the symbiont.1,2 Although alterations in root hair morphology like branching and swelling have been observed in other plants in response to drug treatments3 or genetic perturbations,4, 5, 6 full root hair curling represents a rather specific invention in legumes. The entrapment of the symbiont completes with its full enclosure in a structure called the “infection chamber” (IC),1,2,7,8 from which a tube-like membrane channel, the “infection thread” (IT), initiates.1,2,9 All steps of rhizobium-induced root hair alterations are aided by a tip-localized cytosolic calcium gradient,10,11 global actin re-arrangements, and dense subapical fine actin bundles that are required for the delivery of Golgi-derived vesicles to the root hair tip.7,12, 13, 14 Altered actin dynamics during early responses to NFs or rhizobia have mostly been shown in mutants that are affected in the actin-related SCAR/WAVE complex.15, 16, 17, 18 Here, we identified a polarly localized SYMBIOTIC FORMIN 1 (SYFO1) to be required for NF-dependent alterations in membrane organization and symbiotic root hair responses. We demonstrate that SYFO1 mediates a continuum between the plasma membrane and the cell wall that is required for the onset of rhizobial infections.

Unprepared surface areas, accumulated hard tissue debris, and dentinal crack formation after preparation using reciprocating or rotary instruments: a study in human cadavers.

This study using contralateral teeth from human cadavers assessed the amount of unprepared wall surface areas (USA), accumulated hard tissue debris (AHTD), and dentinal crack formation after root canal preparation using either reciprocating or rotary instruments. Incisors with a single root canal from 11 human mandibles had their root canals prepared with Reciproc or Mtwo. Each contralateral tooth was treated with one of the test instruments in order to create matched pairs. Micro-CT scans were taken before and after preparation to instrument sizes 40 and 50 in both groups. USA and AHTD were evaluated in the full canal length or the apical portion only. Crack formation was also evaluated in the full root length. After size 40, no significant differences in USA and AHTD were observed in the full canal length (P > .05). Separate analysis of the apical 4-mm canal revealed no difference in AHTD, but significantly more USA with Mtwo than Reciproc (P < .05). After size 50, the amount of USA was similar between groups both in the full canal and in the apical canal (P > .05). More AHTD were observed in the full canal after using Mtwo size 50 (P < .05), but no difference occurred in the apical canal only (P > .05). Intragroup analyses showed a significant decrease of USA and a significant increase of AHTD when preparation size increased from 40 to 50 (P < .05). In teeth without any pre-existing detectable dentinal defect (n = 38), crack formation occurred in 4 teeth, 2 from each preparation system. Reciproc instrument size 40 resulted in more prepared areas in the apical canal than Mtwo instrument of the same size. However, the amount of AHTD did not differ between them at this file size. Canal enlargement to size 50 prepared more walls but created more debris. Dentinal defects were produced after preparation with both systems.

Experience with the Freestyle Valve: A Versatile Option

Objective: The Medtronic Freestyle bioprosthesis is a stentless porcine aortic root. It provides a versatile implantation option either as a full root replacement or a sub-coronary aortic valve replacement. In this study we present our experience with the Freestyle valve in all circumstances over a 10-year period. Methods: All consecutive patients (n=70) undergoing Freestyle valve implantation either in the isolated or concomitant (n=9) setting were included between Jan 2009 to Jan 2020. A retrospective analysis of prospectively collected data was undertaken over 10 years. All case notes were reviewed (operation notes and follow up correspondence). Serial follow up echocardiography was reviewed to assess prosthesis function for structural valve deterioration. Echocardiography data was correlated with patient’s clinical status during the follow up period. Mortality data was checked with national registries. Results: In-hospital mortality was 5.7% (n=4). Of the 66 patients, there were 6 deaths during follow up. Surviving patients were followed for a median period of 2 years (IQR 1-3 years). No patients underwent re-intervention for structural valve deterioration. At follow up, 90% patients’ symptoms were consistent with NYHA class I-II and were successfully discharged to their primary care physician. Conclusions: Our experience with the Freestyle valve shows this to be a feasible bioprosthetic valve with good early and late outcomes. It is a versatile option both in the subcoronary position or as a complete aortic root replacement with low morbidity. Our experience has shown that the Freestyle valve is a preferable option in the setting of infective endocarditis with tissue destruction. Long-term follow-up has shown no structural valve deterioration in our experience, with good clinical outcomes. Freestyle valve used as aortic root versus subcoronary position Valve Position Root Replacement Subcoronary 35 35 Redo 18 16 Infective Endocarditis 12 19 Death (follow up) 3 3 Mean Bypass (Cross clamp) time/min 269 (185) 240 (156) Mean haemodynamic data MG- mmHg/PG-mmHg/AVA-cm2 6.6/12.5/1.6 6.0/8.0/0.7 Aortic regurgitation at follow up 0 0