Tooth loss in breast cancer patients: A comparison between tamoxifen-treated and non-treated patients.

BACKGROUND: Tooth loss (TL) affects quality of life and general health. The literature suggesting that tamoxifen treatment in patients with breast cancer (BC) could be associated with alterations in oral health, increasing the risk of TL, is still scarce. This work aimed to determine the relationship between TL and tamoxifen consumption in patients with BC. MATERIAL AND METHODS: This cross-sectional observational study was carried out from July to September 2023 in the medical oncology services of the "Virgen de la Puerta" - ESSALUD High Complexity Hospital and "Dr. Luis Pinillos Ganoza" - IREN Norte - Regional Institute of Neoplastic Diseases, in Trujillo - Peru. Overall, 200 adult patients diagnosed with BC were evaluated, of which 100 consumed tamoxifen and 100 did not. Inter- and intra-rater reliability was determined with respect to TL, resulting in intra-class correlation values RHO = 0.971 and interclass RHO = 0.938. The oncologist of the corresponding service performed BC diagnosis and stage. Poisson regression was used to analyze results with a significance level of p<0.05. RESULTS: No relationship was found between TL and tamoxifen consumption in patients with breast cancer (p= 0.221); however, greater TL was observed in women who consumed tamoxifen for more than one year compared to those who did not use it (p=0.025) and in older adult women compared to young women (p=0.030). CONCLUSIONS: There is a relationship between TL and time of use of tamoxifen in patients with BC, concluding that patients who consumed tamoxifen for more than one year had greater TL than those who did not. Furthermore, no relationship was found between TL and cancer stages, but there was greater TL in older adult patients and also in those who consumed tamoxifen and did not receive chemotherapy or radiotherapy.

Fracture Resistance and Failure Mode of Polyethylene Fiber-reinforced Resin-based Restorations in Structurally Compromised Premolars: an in Vitro Study.

OBJECTIVE: To evaluate the effect of polyethylene fiber-reinforcement on the fracture resistance and fracture mode of extensive resin-based composite (RBC) restorations in structurally compromised maxillary premolars. METHODS AND MATERIALS: Maxillary premolars (54) with specific dimensions and extracted for orthodontic reasons were used. Following mesio-occluso-distal (MOD) cavity preparation and endodontic access, teeth were randomly assigned to one of three restorative protocols (n=18): RBC applied incrementally (I) or reinforced with woven polyethylene fibers (Ribbond) placed horizontally (H) or U-shaped (U). Restored teeth were stored for 45 days in distilled water at 37°C and then loaded monotonically until fracture. Half of the specimens in each group received axial loading (A) and the other half was loaded paraxially (PA). Fracture load data was assessed using two-way analysis of variance and Tukey's post hoc test for multiple comparisons (α=0.05). The fracture initiation and propagation path were analyzed using stereomicroscopy and scanning-electron microscopy. RESULTS: No significant differences were observed for the fracture strength among loading configurations, except for groups IA (825 N) and HA (553 N). Fracture initiated and propagated mainly at and through the RBC restoration in the I group, whereas a shift to the interface was observed in both polyethylene fiber-reinforced groups. Blocking and bridging of cracks were identified around the fibers, especially in specimens of group U. CONCLUSIONS: Incorporation of woven polyethylene fibers to reinforce extensive MOD resin-based composite restorations on endodontically treated premolars reduced the occurrence of cohesive fractures in the restorative material but was unable to increase the fracture resistance of the affected teeth.

Towards recycling of waste carbon fiber: Strength, morphology and structural features of recovered carbon fibers.

Carbon fiber is one of the most widely used materials in high demand applications due to its high specific properties, however, its post-recycling properties limit its use to low performance applications. In this research, the carbon fiber recovering is examined using two methods: two-step pyrolysis and microwave-assisted thermolysis. The results indicate that the fibers recovered by pyrolysis show reduced surface and structural damage, maintaining the original mechanical properties of the fiber with losses below 5%. The fibers recovered by microwaves undergo significant surface changes that reduce their tensile strength by up to 60% and changes in their graphitic structure, increasing their degree of crystallinity by Raman index ID/IG from 1.98 to 2.86 and their amorphous degree by ID"/IG ratio from 0.411 to 1.599. Recovering fibers from microwave technique is 70% faster compared to two step pyrolysis, and provides recycled fibers with superior surface activation with the presence of polar functional groups -OH, -CO, and -CH that react with the epoxy matrix. The thermal, morphological, structural and mechanical characterizations of the recovered fibers detailed in this work provide valuable findings to evaluate their direct reuse in new composite materials.

Endoscopic Treatment for Vesicoureteral Reflux in Recurrent Urinary Tract Infections in Kidney Transplant: Experience of One Center.

Vesicoureteral reflux (VUR) after renal transplantation in adult patients has been reported. In renal transplant recipients, symptomatic urinary tract infection can cause high morbidity despite improved immunosuppressive and antibiotic treatment. In our country there have been few reported cases about use of copolymer of dextranomer and hyaluronic acid (DX-HA) injection in a renal transplant. We present 3 cases of recurrent or complicated infections with evidence of high-grade VUR, which were treated with DX-HA. Only 1 case had a partial remission; however, there were no episodes of urinary tract infection in 12 months of follow-up. Suburethral injection is an endoscopic treatment modality with low morbidity in our country.

Manejo odontopediátrico de pacientes con enferemedad de Von Willebrand. Reporte de un caso clínico / Dental management of patient with von Willebrand disease, Report of a case

La enfermedad de Von Willebrand es de origen autosómica dominante que se caracteriza por sangrado prolongado con recuento plaquetario normal debido a una deficiencia cualitativa o cuantitativa del factor Von Willebrand, que es una proteína necesaria para iniciar la adherencia plaquetaria al subendotelio e iniciar el proceso hemostático. Una deficiencia de este factor causa sangrados prolongados de diferente intensidad. Reporte del caso: Se presentó al Hospital del Niño DIF, Hidalgo, un paciente masculino de7 años 6 meses de edad, el cual fue diagnosticado a los 4 años con enfermedad de Von Willebrand y remitido para realizar exodoncias dentales. El paciente no contaba con subtipo de la enfermedad. Se decide realizar la rehabilitación integral en quirófano transfundiendo crioprecipitados. Debido a la presencia de lesiones cariosas de diversos grados y evidencia de infección de origen apical, se realizaron 4 tratamientos pulpares, 4 coronas de acero cromo y 3 extracciones con medios hemostáticos y sutura de heridas. Conclusiones: La rehabilitación odontológica bajo anestesia general de este paciente se consideró exitosa, ya que se realizó en una sola cita, transfundiendo crioprecipitados, sin tener complicaciones durante el procedimiento...

The Von Willebrand disease is an autosomal dominant origin characterized by prolonged bleeding with normal platelet count due to a qualitative or quantitative deficiency of Von Willebrand factor, a protein required to initiate platelet adhesion to sub-endothelium and initiate the process hemostatic. A deficiency of this factor causes prolonged bleeding of varying intensity. Case report: A male patient 7 years 6 months old, was presented to the Hospital del Niño DIF, Hidalgo, who was diagnosed at age 4 with Von Willebrand disease and referred for dental extractions. The patient had no disease subtype. It was decided to perform comprehensive surgical rehabilitation transfusing cryoprecipitate. Due to the presence of carious lesions of diverse degrees and evidence of infection of apical origin, 4 pulp treatments, 4 chrome steel crowns, 3 extractions were realized with hemostatic and wound closure means. Conclusions: The dental rehabilitation under general anesthesia in this patient was considered successful, as was done in one appointment, and transfusing cryoprecipitate, without complications during the procedure...

Adsorción de fluoruros en hidroxiapatita sintética / Fluoride adsorption in synthetic hydroxiapatite

Se estudió la adsorción de: fluoruro de sodio, fluoruro de amonio, fluoruro de estaño y monofluorfosfato de sodio en hidroxiapatita sintética bufferizada en saliva artificial a los pH 4,7; 5,5; 6,1; a través de dos modelos. En el primer modelo (columna de elución) se procedió a eluir los fluoruros de la columna de hidroxiapatita bufferizada a los pH anteriores. La determinación de flúor se hizo por métodos potenciométrico con electrodo de flúor. Los resultados de la elución indican que los fluoruros de sodio y estaño presentan niveles de elución diferentes a los pH estudiados. En cambio el fluoruro de amonio no presenta diferencias. Los resultados de la incubación nos muestra que el fluoruro de amonio presenta la mayor adsorción, el fluoruro de sodio tiene un valor levemente menor, y el monofluorfosfato de sodio el valor más bajo de todos. Además notamos que la adsorción disminuye con el aumento del pH para los tres fluoruros. La comparación de ambos modelos nos muestran que la incubación presenta valores más altos de adsorción que la elución para los pH estudiados

Desmineralización de hidroxiapatita y dentina por EDTA / Demineralizing of hydroxiapatita and dentine by EDTA

La magnitud de la desmineralización por solvatación ácida es casi tan importante como la quelación por EDTA, procesos que ocurren simultáneamente durante el tratamiento con EDTA del diente. Un 45% del mineral disuelto se debe al protón, pero esta solvatación demora más tiempo que la quelación. Al acidificarse el medio, el quelato CaEDTA se disocia. Esto junto con un aumento de la concentración de HPO=4, según el modelo de Van Dijk, haría disminuir la velocidad de desmineralización. Una estimación rápida de las concentraciones de estas especies en el diente ([Ca+2]=10-6M,[HPO=4]=10-3M,[OH-]=10-8M) nos muestra que a pH6 la reacción carece de fuerza motriz y la desmineralización por EDTA se autolimita