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The aim of the present study was to investigate the influence of the mechanical properties of three different calcium-silicate-based cements on the stress distribution of three different retrograde cavity preparations. Biodentine™ "BD", MTA Biorep "BR", and Well-Root™ PT "WR" were used. The compression strengths of ten cylindrical samples of each material were tested. The porosity of each cement was investigated by using micro-computed X-ray tomography. Finite element analysis (FEA) was used to simulate three retrograde conical cavity preparations with an apical diameter of 1 mm (Tip I), 1.4 mm (Tip II), and 1.8 mm (Tip III) after an apical 3 mm resection. BR demonstrated the lowest compression strength values (17.6 ± 5.5 MPa) and porosity percentages (0.57 ± 0.14%) compared to BD (80 ± 17 MPa-1.22 ± 0.31%) and WR (90 ± 22 MPa-1.93 ± 0.12%) ( p < 0.05). FEA demonstrated that the larger cavity preparation demonstrated higher stress distribution in the root whereas stiffer cement demonstrated lower stress in the root but higher stress in the material. We can conclude that a respected root end preparation associated with cement with good stiffness could offer optimal endodontic microsurgery. Further studies are needed to define the adapted cavity diameter and cement stiffness in order to have optimal mechanical resistance with less stress distribution in the root.

Purpose: To evaluate the impact of immediate and delayed zirconia implant placement on crestal bone loss and the clinical outcomes achieved with this approach 1 year after prosthetic loading. Further objectives were to evaluate the influence of age, sex, smoking, implant dimensions, platelet-rich fibrin application and location of the implants in the jawbone on the crestal bone level., Materials and Methods: Clinical and radiographic analysis were performed to evaluate the success rates for both groups. The data were analysed statistically through a linear regression analysis., Results: No significant difference was found between immediate and delayed implant placement concerning the amount of crestal bone loss. Sex, age, bone augmentation, diabetes and prosthetic complications did not have a statistically significant influence; only smoking had a negative and statistically significant influence on crestal bone loss (P < 0.05)., Conclusions: Immediate or delayed placement of one-piece zirconia implants may be a good alternative to the use of titanium implants concerning success and survival.

Angiotensin II (Ang II)-dependent stimulation of the AT 1 receptor in proximal tubules increases sodium reabsorption and blood pressure. Reabsorption is driven by the Na,K-pump that is acutely stimulated by Ang II, which requires phosphorylation of serine-938 (S938). This site is present in humans and only known to phosphorylated by PKA. Yet, activation of AT 1 decreases cAMP required to activate PKA and inhibiting PKA does not block Ang II-dependent phosphorylation of S938. We tested the hypothesis that Ang II-dependent activation is mediated via increased phosphorylation at S938 through a PI3K/AKT-dependent pathway. Experiments were conducted using opossum kidney cells, a proximal tubule cell line, stably co-expressing the AT 1 receptor and either the wild-type (α-1.wild-type) or an alanine substituted (α-1.S938A) form of rat kidney Na,K-pump. A 5-min exposure to 10 pM Ang II significantly activated Na,K-pump activity (56%) measured as short-circuit current across polarized α-1.wild-type cells. Wortmannin, at a concentration that selectively inhibits PI3K, blocked that Ang II-dependent activation. Ang II did not stimulate Na,K-pump activity in α-1.S938A cells. Ang II at 10 and 100 pM increased phosphorylation at S938 in α-1.wild-type cells measured in whole cell lysates. The increase was inhibited by wortmannin plus H-89, an inhibitor of PKA, not by either alone. Ang II activated AKT inhibited by wortmannin, not H-89. These data support our hypothesis and show that Ang II-dependent phosphorylation at S938 stimulates Na,K-pump activity and transcellular sodium transport., (© 2022 The Authors. Physiological Reports published by Wiley Periodicals LLC on behalf of The Physiological Society and the American Physiological Society.)

The purpose of the present study was to evaluate the physicochemical properties and antibacterial activity of three calcium silicate cements. Mineral trioxide aggregate (MTA Biorep “BR”), Biodentine (BD) and Well-Root PT (WR) materials were investigated using scanning electron microscopy (SEM) at 24, 72 and 168 h of immersion in phosphate buffered saline (PBS). The antibacterial activity against Enterococcus faecalis (E. faecalis), the solubility, roughness, pH changes and water contact angle were also analyzed. All results were statistically analyzed using a one-way analysis of variance test. Statistically significant lower pH was detected for BD than WR and BR (p < 0.05). No statistical difference was found among the three materials for the efficacy of kill against E. faecalis (p > 0.05). Good antibacterial activity was observed (kill 50% of bacteria) after 24 h of contact. The wettability and the roughness of BR were higher than for the other cements (p < 0.05). BD was more soluble than WR and BR (p < 0.05). In conclusion, the use of bioceramic cements as retrograde materials may play an important role in controlling bacterial growth and in the development of calcium phosphate surface layer to support healing. Moreover, the premixed cement was easier to use than powder−liquid cement.

Prurigo pigmentosa (PP) is a rare pruritic condition with idiopathic etiology that affects mostly females. It most commonly presents as a rash on the neck and trunk. We report the occurrence of PP in a young woman on two separate occasions; her first episode was following a ketogenic diet and second after undergoing a laparoscopic gastric sleeve surgery. This presents as a unique case because, to our knowledge, PP has only been reported in a small number of cases in the Western world. This presentation could be suggestive of a stronger relationship between PP and the metabolic state of the body. It also outlines the effectiveness of treatment options currently in use for treating PP., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, Alkhouri et al.)

Merkel cell carcinoma (MCC) is a rare, rapidly growing, and highly malignant cutaneous tumor that typically presents in elderly males as an erythematous or violaceous plaque or nodule in sun-exposed areas. Risk factors include long-term ultraviolet (UV) exposure, Merkel cell polyomavirus (MCV) infection, immunosuppression, and lymphoproliferative disorders such as chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL). Given the aggressive nature of this tumor, patients may present with nodal and distal metastasis. Locoregional disease can be managed with definitive radiotherapy or surgery with or without adjuvant radiotherapy, depending on the case. Disseminated disease, on the other hand, often requires a multidisciplinary tumor board consultation to individually tailor the treatment. Possible treatments include systemic therapy with chemotherapy or immunotherapy, radiotherapy, and surgery. Here we report a case of a patient with a medical history significant for chronic lymphocytic leukemia and diffuse large B-cell lymphoma who presented with a rapidly growing lesion that contained neighboring MCC and CLL/SLL on biopsy. Management included immunotherapy with pembrolizumab and radiotherapy to limit the tumor's growth and spread. To the best of our knowledge, the coexistence of all three malignancies in a person is rare and has not been reported previously., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2021, Alkhouri et al.)

Peripheral artery disease (PAD) is a significant cause of morbidity and mortality in the world. Critical limb ischemia is a complication of PAD that leads to severe pain at rest, numbness, and absent or diminished pulses in the legs or feet. Revascularization with surgery or endovascular intervention is required to re-establish blood flow to the affected areas. Failure to respond to medical and/or surgical treatment can lead to amputations. The decision to amputate one's limb can be very challenging. Here, we report a patient with critical limb ischemia who refused a below-the-knee amputation and self-treated with medicinal leech therapy, or hirudotherapy. His symptoms including his pain, burning, and numbness improved significantly following six months of therapy., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2021, Afify et al.)

Aim: Distraction osteogenesis (DO) is a treatment option for patients with maxillary hypoplasia secondary to cleft lip and palate (CLP)., Purpose: The aim of this study is to present a technique for maxillary DO using Le Fort I osteotomy with rigid external distraction (RED) system., Subjects and Methods: The patient presented in this paper was an Asian female with CLP aged 13 years and 6 months. She presented with severe midfacial deficiency with a Class III dental malocclusion with a negative overjet and concave facial profile. Cone-beam computed tomography images were recorded preoperatively and the operation performed involved a high Le Fort I osteotomy. The appliance fabricated was banded to upper first molars used for anchorage of the RED system. Distraction of the maxilla was initiated after 7-day latency period., Results: Postoperative cephalometric analysis showed maxillary advancement anteriorly and superiorly, the total distraction treatment period was 10 days. The maxillary advancement was 10.5 mm and the SNA angle increased from 67.5° to 77.9°. Furthermore, the ANB angle changed from -9.8° to 1.6° and the occlusion changed from Class III to Class I. The profile of the face changed from concave to convex and a much better esthetic result was achieved., Conclusion: The study suggests RED system to be a reliable alternative procedure for the treatment of midfacial hypoplasia with or without cleft. Furthermore, it minimizes the risk of the surgical procedure and shortens the operating time., Competing Interests: There are no conflicts of interest.