Antibiotic therapy for the prevention of osteoradionecrosis following tooth extraction in head-and-neck cancer patients postradiotherapy: An 11-year retrospective study

Introducción: Una de las complicaciones más importantes de la radioterapia (RT) para el cáncer de cabeza y cuello (CCC) es la osteorradionecrosis (ORN) de los maxilares, que surge sobre todo a raíz de las extracciones dentales. El tratamiento de la ORN sigue representando un gran reto; por lo tanto, la prevención es de suma importancia. Así pues, el presente estudio tenía como objetivo evaluar retrospectivamente un protocolo de tratamiento antibiótico sistémico perioperatorio para la prevención de la ORN tras la extracción dental en pacientes con cabeza y cuello tras RT conformada 3D. Materiales y métodos: Se realizó una revisión retrospectiva de historias clínicas considerando pacientes HNC sometidos a RT en el periodo comprendido entre 2008 y 2019. Recibieron necesariamente antibioticoterapia oral con Clindamicina 300 mg cada 8 h durante 10 días, con la primera dosis 3 días antes de la extracción dentaria. Resultados: Cuarenta y nueve pacientes cumplían los criterios de estudio, con un total de 107 dientes extraídos. En cuanto a los 47 pacientes que no desarrollaron ORN, se identificaron 103 extracciones dentales (96,3%). Solo dos pacientes desarrollaron ORN en dos dientes adyacentes (3,7%). Conclusiones: El protocolo de terapia antibiótica sistémica perioperatoria propuesto parece ser eficaz para prevenir la ORN tras la extracción dental en pacientes con HNC postirradiado.Introduction: One of the most important complications of radiotherapy (RT) for head-and-neck cancer (HNC) is osteoradionecrosis (ORN) of the jaws, which mostly arises from tooth extractions. The ORN treatment still represents a great challenge; therefore, the prevention is of paramount importance. Thus, the present study aimed to evaluate retrospectively a perioperative systemic antibiotic therapy protocol for the prevention of ORN following tooth extraction in head-and-neck patients post-3D conformal RT. Materials and Methods: A retrospective medical record review was performed considering HNC patients submitted to RT in the period between 2008 and 2019. They necessarily received oral antibiotic therapy with Clindamycin 300 mg every 8 h for 10 days, with the first dose 3 days before the tooth extraction. Results: Forty-nine patients met the study criteria, with a total of 107 teeth extracted. Regarding the 47 patients who did not develop ORN, 103 tooth extractions were identified (96.3%). Only two patients developed ORN at two adjacent teeth sites (3.7%). Conclusion: The proposed perioperative systemic antibiotic therapy protocol seems to be efficient to prevent ORN following tooth extraction in postirradiated HNC patients

Leukocyte- and platelet-rich fibrin does not provide any additional benefit for tooth extraction in head and neck cancer patients post-radiotherapy : a randomized clinical trial

One of the most important complications of radiotherapy (RT) for head and neck cancer (HNC) is osteoradionecrosis (ORN) of the jaws, arising mainly from tooth extractions. Thus, the present study aimed to evaluate the efficacy of leukocyte- and platelet-rich fibrin (L-PRF) in preventing ORN following tooth extraction in post-irradiated HNC patients, as well as other postoperative complications. 23 patients previously submitted to conventionally fractionated 3D-conformational RT for HNC underwent atraumatic tooth extractions with perioperative antibiotic therapy. Besides, they were randomly assigned to receive L-PRF clots to fill and cover the extraction sockets (n=11, Test Group) or not (n=12, Control Group). A visual analog scale was used to quantify postoperative pain on the 3rd and 7th days. For ORN diagnosis, patients were clinically assessed for up to 180 days. Other postoperative complications (edema, alveolitis, suture dehiscence, continuous bleeding, and oroantral communication) were also evaluated within this period. No case of ORN or another surgical complication was observed and there were no differences in the postoperative pain scores between the groups on the 3rd and 7th days. L-PRF did not seem to provide any additional benefits than those achieved by the combination of the surgical and drug protocols used for tooth extractions in the post-irradiated HNC patients

Hyaluronidase following buccal infiltrations of articaine with epinephrine for anesthesia of mandibular first molars : a split-mouth, double-blind, placebo-controlled randomized clinical trial

Adjunctive hyaluronidase has been widely used for ophthalmic anesthesia; however, in Dentistry, very few studies are available so far. Thus, the present study aimed to evaluate anesthetic outcomes of adjunctive hyaluronidase administration following bucc

Impact of radiotherapy on mandibular bone : a retrospective study of digital panoramic radiographs

Purpose: The purpose of this study was to investigate the impact of radiotherapy on mandibular bone tissue in head and neck cancer patients through an analysis of pixel intensity and fractal dimension values on digital panoramic radiographs.Materials and methods: Thirty patients with radiographic records from before and after 3-dimensional (3D) conformational radiotherapy were selected. A single examiner carried out digital analyses of pixel intensity values and fractal dimensions, with the areas of interest unilaterally located in the right angle medullary region of the mandible below the mandibular canal and posterior to the molar region.Results: Statistically significant decreases were observed in the mean pixel intensity (P=0.0368) and fractal dimension (P=0.0495) values after radiotherapy.Conclusion: The results suggest that 3D conformational radiotherapy for head and neck cancer negatively affected the trabecular microarchitecture and mandibular bone mass.peer-reviewe

Scheduling of a hydro producer considering head-dependency, price scenarios and risk-aversion

In this paper, a mixed-integer quadratic programming approach is proposed for the short-term hydro scheduling problem, considering head-dependency, discontinuous operating regions and discharge ramping constraints. As new contributions to earlier studies, market uncertainty is introduced in the model via price scenarios, and risk aversion is also incorporated by limiting the volatility of the expected profit through the conditional value-at-risk. Our approach has been applied successfully to solve a case Study based on one of the main Portuguese cascaded hydro systems, requiring a negligible computational time

Replacement of pulmonary artery trunk in sheep using tubular valved heterograft in non-aldehydic preservation

INTRODUCTION: The cardiac bioprostheses are related to thromboembolic events, infectious and degenerative diseases. Wear is mainly attributed to the denaturation of collagen. Glutaraldehyde, the predominant method of preservation of bioprostheses, favors the calcification process and limits their durability. Several techniques try to contain the degenerative process of bioprostheses. OBJECTIVES: To evaluate the process of calcification in vivo pulmonary valve heterografts preserved in non-aldehydic (L-Hydro®). METHODS: Seventeen sheep underwent replacement of the pulmonary artery valved tubular grafts of bovine pericardium. The animals were divided into two groups: Group L-Hydro® (test / n = 14) and Group Glutaraldehyde (control / n = 3). About 150 days after implantation the animals were sacrificed, necropsied and implants subjected to a pathological study, radiological evaluation and measurement of calcium by atomic absorption spectrophotometry. Statistical analysis was obtained through the Fisher's exact test, Student's t or Mann-Whitney test (significance: 5%). RESULTS: The radiological evaluation, the macroscopic and microscopic measurement of serum calcium by atomic absorption spectrophotometry showed increased calcification of the prosthetic group Glutaraldehyde, when compared to denture-HydroR Group L (P = 0.001). Seven animals in Group L-Hydro® (50%) had adherence of the leaflets to the wall of the tube (P = 0.228). CONCLUSIONS: Prostheses preserved in L-Hydro® were more resistant to calcification when compared with glutaraldehyde preserved.INTRODUÇÃO: As biopróteses valvares cardíacas estão relacionadas a eventos tromboembólicos, infecciosos e degenerativos. Seu desgaste é atribuído principalmente à desnaturação do colágeno. O glutaraldeído, método predominante de preservação de biopróteses, favorece o processo de calcificação e limita sua durabilidade. Diversas técnicas tentam conter o processo degenerativo das biopróteses. OBJETIVO: Avaliar o processo de calcificação, in vivo, de heteroenxertos pulmonares valvados, preservados em meio não-aldeídico (L-Hydro®). MÉTODOS: Dezessete carneiros foram submetidos à substituição do tronco da artéria pulmonar por enxerto tubular valvado de pericárdio bovino. Os animais foram distribuídos em dois grupos: Grupo L-Hydro® (teste / n=14) e Grupo Glutaraldeído (controle /n=3). Cerca de 150 dias pós-implante os animais foram sacrificados, necropsiados e as próteses submetidas a estudo anatomopatológico, avaliação radiológica e dosagem do cálcio por espectrofotometria de absorção atômica. A análise estatística foi obtida por meio dos testes exato de Fisher, T de Student ou Mann-Whitney (significância: 5%). RESULTADOS: A avaliação radiológica, macroscopia, microscopia e dosagem de cálcio por espectrofotometria de absorção atômica demonstraram maior calcificação nas próteses do Grupo Glutaraldeído, quando comparadas às próteses do Grupo L-Hydro® (P=0,001). Sete animais do Grupo L-Hydro® (50%) apresentaram aderência das cúspides à parede do tubo (P=0,228). CONCLUSÕES: As próteses preservadas em L-Hydro® demonstraram-se mais resistentes à calcificação, quando comparadas às preservadas em glutaraldeído.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de MedicinaLabcor LaboratórioUNIFESP, EPMSciEL

Vascular flora of the Legado das Águas, Reserva Votorantim, municipalities of Tapiraí, Miracatú and Juquiá, São Paulo, Brazil

We present  a list of vascular plants found in Legado das Águas, Reserva Votorantim, a private reserve having an area of approximately 35,000 ha that spans the municipalities of Tapiraí, Miracatú, and Juquiá, in the state of São Paulo, Brazil. The reserve is part of a complex of state-protected areas including Alto Ribeira Touristic State Park, Intervales State Park , Carlos Botelho State Park, Jurupará State Park, and Serra do Mar State Park. Together, these form an important and large area of continuous and well-preserved forest. Our study, which involved two main floristic surveys in March/April 2013 and April 2014, recorded 768 species, representing 131 families and 432 genera. The majority of species were angiosperms (619) representing 106 families and 370 genera. There were also two species of gymnosperms belonging to two genera in separate families; 147 species of ferns and lycophytes belonging to 23 families and 60 genera. In demonstrating the presence of almost 800 species of plants, of which 16 are threatened, our study highlights the importance of floristic surveys and the critical role of private protected areas in managing and preserving native flora

Geography and ecology shape the phylogenetic composition of Amazonian tree communities

Aim: Amazonia hosts more tree species from numerous evolutionary lineages, both young and ancient, than any other biogeographic region. Previous studies have shown that tree lineages colonized multiple edaphic environments and dispersed widely across Amazonia, leading to a hypothesis, which we test, that lineages should not be strongly associated with either geographic regions or edaphic forest types. Location: Amazonia. Taxon: Angiosperms (Magnoliids; Monocots; Eudicots). Methods: Data for the abundance of 5082 tree species in 1989 plots were combined with a mega-phylogeny. We applied evolutionary ordination to assess how phylogenetic composition varies across Amazonia. We used variation partitioning and Moran\u27s eigenvector maps (MEM) to test and quantify the separate and joint contributions of spatial and environmental variables to explain the phylogenetic composition of plots. We tested the indicator value of lineages for geographic regions and edaphic forest types and mapped associations onto the phylogeny. Results: In the terra firme and várzea forest types, the phylogenetic composition varies by geographic region, but the igapó and white-sand forest types retain a unique evolutionary signature regardless of region. Overall, we find that soil chemistry, climate and topography explain 24% of the variation in phylogenetic composition, with 79% of that variation being spatially structured (R$^{2}$ = 19% overall for combined spatial/environmental effects). The phylogenetic composition also shows substantial spatial patterns not related to the environmental variables we quantified (R$^{2}$ = 28%). A greater number of lineages were significant indicators of geographic regions than forest types. Main Conclusion: Numerous tree lineages, including some ancient ones (>66 Ma), show strong associations with geographic regions and edaphic forest types of Amazonia. This shows that specialization in specific edaphic environments has played a long-standing role in the evolutionary assembly of Amazonian forests. Furthermore, many lineages, even those that have dispersed across Amazonia, dominate within a specific region, likely because of phylogenetically conserved niches for environmental conditions that are prevalent within regions

Geography and ecology shape the phylogenetic composition of Amazonian tree communities

AimAmazonia hosts more tree species from numerous evolutionary lineages, both young and ancient, than any other biogeographic region. Previous studies have shown that tree lineages colonized multiple edaphic environments and dispersed widely across Amazonia, leading to a hypothesis, which we test, that lineages should not be strongly associated with either geographic regions or edaphic forest types.LocationAmazonia.TaxonAngiosperms (Magnoliids; Monocots; Eudicots).MethodsData for the abundance of 5082 tree species in 1989 plots were combined with a mega-phylogeny. We applied evolutionary ordination to assess how phylogenetic composition varies across Amazonia. We used variation partitioning and Moran's eigenvector maps (MEM) to test and quantify the separate and joint contributions of spatial and environmental variables to explain the phylogenetic composition of plots. We tested the indicator value of lineages for geographic regions and edaphic forest types and mapped associations onto the phylogeny.ResultsIn the terra firme and várzea forest types, the phylogenetic composition varies by geographic region, but the igapó and white-sand forest types retain a unique evolutionary signature regardless of region. Overall, we find that soil chemistry, climate and topography explain 24% of the variation in phylogenetic composition, with 79% of that variation being spatially structured (R2 = 19% overall for combined spatial/environmental effects). The phylogenetic composition also shows substantial spatial patterns not related to the environmental variables we quantified (R2 = 28%). A greater number of lineages were significant indicators of geographic regions than forest types.Main ConclusionNumerous tree lineages, including some ancient ones (>66 Ma), show strong associations with geographic regions and edaphic forest types of Amazonia. This shows that specialization in specific edaphic environments has played a long-standing role in the evolutionary assembly of Amazonian forests. Furthermore, many lineages, even those that have dispersed across Amazonia, dominate within a specific region, likely because of phylogenetically conserved niches for environmental conditions that are prevalent within regions