Allogenic platelet-rich plasma in induced ulcers in rat's cornea / [Plasma rico em plaquetas alogênico em úlceras de córnea induzidas em ratos]

The objective in this study was to evaluate the clinic effect of applying allogenic platelet-rich plasma (PRP) heated or not, for treating cornea ulcers, including the dosage of PDGF-BB in the cornea. The ulcers were induced, standardizing the left eye from 81 rats (Ratus norvegicus, albinus variety), assigned randomly into three groups (N=27): control group (CG) which did not receive any topic treatment; heated PRP group (GA) and PRP group (GP), which received topical treatment every eight hours for five days. Each group underwent evaluation at 24 hours (M1), three days (M3) and five days (M5). The clinical exam evaluated the opacity, vascularization and corneal repair. The corneal PDGF-BB was dosed through the ELISA method. The corneal opacity was decreased in PRP-treated animals (GA and GP) and corneal repair time reduced when compared to CG at M1 and M5. Furthermore, GP showed greater vascularization at M3 compared to M1. Applied allogenic PRP eye drops, heated or not, speed up corneal healing, and reduce corneal repair time. However, the corneal PDGF concentration was not altered in any of the treatments.(AU)

Objetivou-se avaliar o efeito clínico da aplicação de plasma rico em plaquetas alogênico (PRP) aquecido ou não, no tratamento de úlceras de córnea, como a dosagem de PDGF-BB na córnea. As úlceras foram induzidas, padronizando-se o olho esquerdo de 81 ratos (Rattus norvegicus, variedade albinus), aleatoriamente, nos três grupos (N = 27): grupo controle (CG), que não recebeu nenhum tratamento tópico; grupo PRP aquecido (GA) e grupo PRP (GP), que receberam tratamento tópico a cada oito horas, durante cinco dias. Cada grupo foi subdividido em 24 horas (M1), três dias (M3) e cinco dias (M5). O exame clínico avaliou a opacidade, a vascularização e o reparo corneano. O PDGF-BB corneano foi dosado pelo método Elisa. Houve diminuição da opacidade da córnea nos animais tratados com PRP (GA e GP) e diminuição do tempo de reparo da córnea em comparação com CG, M1 e M5. Além disso, foi observada maior vascularização no GP no momento M3 em relação ao M1. A aplicação de colírios de PRP alogênico, aquecidos ou não, acelera a cicatrização da córnea, além de reduzir o tempo de reparo da córnea. No entanto, a concentração de PDGF na córnea não se alterou em nenhum dos tratamentos.(AU)

Root canal treatment of compromised teeth as alternative treatment for patients receiving bisphosphonates: 60-month results of a prospective clinical study.

AIM: This 60-month prospective study aimed to evaluate tooth survival and healing rates after root canal treatment in patients taking bisphosphonates (BPs). Secondary outcomes were complications and clinical variables observed during and after treatment. METHODS: Root canal treatment was performed using manual K-file canal instrumentation and a carrier-based filling technique with an epoxy resin-based sealer. Teeth without adequate root/crown integrity were restored by trained operators at the tissue level (TL group) to prevent occlusal/mechanical stress and to enable periapical lesion healing without the risk of root fracture. Other teeth were restored with normal occlusal contacts (OC group). Healthy patients who had undergone one or more root canal treatments of the same type constituted the control group. The relationships of the following variables to survival and health status were examined (chi-squared test and multivariate analysis, P = 0.05): age, gender, smoking habit, tooth location, treatment type, BPs treatment, BPs exposure, initial periapical index (PAI) and occlusal restoration. Survival curves were constructed using Kaplan-Meier analysis, with extraction serving as the end-point. RESULTS: In total, 65 patients with 109 root canal-treated teeth who were taking BPs were included. At 60 months, data from 57 patients (52F, 5M; median age 65.7 ± 8.6 years) who had undergone 96 root canal treatments were analysed (drop-out rate = 16.9%). The survival rate was 85%, and the success rate was 76%. The control group consisted of 46 patients (21F, 25M; median age 60.3 ± 7.2 years) who had undergone 102 root canal treatments. The survival rate was 88%, with 12 teeth lost during follow-up. The success rate was 73%. In the BP group, 55 teeth were restored normally (OC group) and 41 teeth were restored at the tissue level (TL group). No difference in the success or survival rate was observed between the BP and control groups (P > 0.05). Univariate Kaplan-Meier analysis revealed that only tooth type significantly affected survival status in the BP group. The analysis revealed the clinical relevance of smoking, tooth location and initial PAI on patients' health status (P < 0.05). CONCLUSION: Root canal treatments and post-endodontic restoration with tissue-level filling procedures represent a safe approach for severely damaged teeth in patients receiving BPs having comparable results to root filled teeth restored with occlusal contacts and to the control group.

Tomographic and anatomical study of the orbit and nasolacrimal duct in capybaras (Hydrochoerus hydrochaeris-Linnaeus, 1766).

The objective of this study was to describe the reference values of cranial measurements of capybaras, correlating the ocular orbit with the nasolacrimal duct. The documentation of its results can contribute to standardizing characteristics of anatomical normality and favouring the correct diagnosis and treatment of changes. The capybara carcasses, maintained by freezing, were distributed in two groups (G) designated GA (n = 12) adult animals (A) and GY (n = 13) for young animals (Y). All subjects underwent dacryocystography examination by computed tomography (CT) and cranial measurements. Descriptive analyses of cranial and nasolacrimal duct measurements and statistical analysis of the Pearson correlation with the variable weight were performed. In GA, there was no correlation between the nasolacrimal and cranial duct measurements. However, in the GY, a correlation was verified with facial length (r = .6233), facial width (r = .5771), cranial height (r = .6981), cranial length (r = .7116), total right length (r = .7517) and left length (r = .7999). Thus, in the young animals, cranial length measurements were strongly correlated with nasolacrimal duct lengths. However, this biological behaviour was not observed in adults, demonstrating stability in development. The capybara's ocular orbit was found to be circular and incomplete, with developed zygomatic process of the maxilla. CT dacryocystography is indicated to evaluate the nasolacrimal canal pathway in capybaras, emphasizing the importance of normal anatomical study to aid in treating animals affected by diseases.

A 20-year historical prospective cohort study of root canal treatments. A Multilevel analysis.

AIM: To evaluate the number of healthy and functional root filled teeth of patients included in a recall programme for at least 20 years. METHODOLOGY: Teeth were root filled by a single specialist following manual canal instrumentation, lateral/vertical compaction of gutta-percha and restored with glass-ionomer cements and bonding system/composite resin. In a large percentage of teeth, a metal-ceramic crown was placed during follow-up. Patients included in the recall programme (n = 130) were blindly assessed both clinically and radiographically (every 2 years) to evaluate clinical symptoms and periapical status (PAI). The following variables were analysed: age, tooth location, tooth type, initial diagnosis, PAI, root filling length and coronal restoration type. Chi-square test and multilevel analysis were performed to detect variables associated with treatment functionality and disease/lesions (P < 0.05). A cumulative teeth survival curve was constructed by means of Kaplan-Meier using extractions as the end-point. RESULTS: At the 20-year recall, 72 patients (31 M, 41 F; mean age 57.7 ± 8.29 years; 196 teeth) completed the follow-up. Thirty-six patients were excluded for medical complications or died before the end of the study. Drop-outs consisted of 22 patients (17%) who did not complete the follow-up. Single metal-ceramic crowns were positioned after 4-6 months in 40% of teeth. Composite restorations were replaced with single metal-ceramic crowns during the follow-up in 53% of teeth after 8-19 years. Of 196 teeth, 155 were classified as Survived (79%), 128 of which (65%) were Healthy (PAI ≤ 2). Thirty-nine teeth (20%) were extracted for nonendodontic reasons. Twenty-nine teeth (15%) were classified as: re-exacerbation (11 teeth; 5.6%) or persistent asymptomatic lesions (18 teeth; 9%). Only two re-exacerbated teeth were extracted. Multilevel analysis confirmed the clinical relevance of tooth type (P = 0.001) on Survived and healthy teeth (P = 0.007). Tooth location (P = 0.0045) and initial diagnosis (P = 0.019) significantly affected only Healthy teeth. CONCLUSIONS: Root filled teeth were more frequently extracted for non-endodontic reasons rather than for endodontic disease. The majority of teeth with adequate root fillings, adequate restorations and included in a recall programme remained functional and healthy for more than 20 years.

Survival and periapical health after root canal treatment with carrier-based root fillings: five-year retrospective assessment.

AIM: This retrospective study explored survival and periapical healing outcomes in teeth root filled with Thermafil obturators. METHODOLOGY: Root canals of 213 teeth (94 subjects, mean age 48 ± 13 years), instrumented with a step-down technique, irrigated with 5% NaOCl and 10% EDTA and filled with Thermafil and AH Plus sealer, were involved in a recall programme. Teeth were retrospectively re-examined after 5 ± 1 years in a controlled environment. Clinical and radiographic data that were collected included the following: preoperative Periapical Index (PAI) score and signs/symptoms, treatment type, root filling length and presence/absence of voids, restoration type, follow-up PAI score and signs/symptoms. Teeth were considered 'healthy' (PAI ≤ 2, no signs/symptoms) or 'diseased' (PAI ≥ 3, signs/symptoms present, retreated, extracted for endodontic reasons). Two PAI-calibrated examiners assessed outcomes blinded to preoperative status. Bivariate and multilevel analyses were performed at level of patient and tooth (α = 5%). RESULTS: Of 213 teeth treated, 187 (88%) survived and 26 were extracted, six (3%) for persistent endodontic infection (considered 'diseased'), and 20 (9%) for root fracture, periodontal disease or coronal fracture (excluded from analysis). Whilst survival was significantly associated with tooth type (P = 0.015), type of treatment (P = 0.012) and pulpal/periapical diagnosis (P = 0.035), none of these variables were substantiated as survival predictors by the multilevel analysis. A total of 164 of 193 teeth (85%) were assessed as 'healthy', with significantly higher (chi-square; P < 0.04) 'healthy' rates for teeth with PAI score ≤2 and root fillings of adequate length. Multilevel analysis identified PAI score ≤2 (P = 0.002) as the only predictor of periapical health. CONCLUSIONS: In this 5 ± 1 year retrospective assessment, survival and healing rates after root canal treatment with Thermafil root fillings were comparable to those previously reported for conventional root filling techniques.

Properties of BioRoot RCS, a tricalcium silicate endodontic sealer modified with povidone and polycarboxylate.

AIM: To evaluate the chemical and physical properties of a tricalcium silicate root canal sealer containing povidone and polycarboxylate (BioRoot RCS), a calcium silicate MTA-based sealer containing a salicylate resin (MTA Fillapex), a traditional eugenol-containing sealer (Pulp Canal Sealer) and an epoxy resin-based root canal sealer (AH Plus). METHODOLOGY: Calcium release, pH, setting time, water sorption, volume of open pores, volume of impervious portion, apparent porosity and weight loss were measured. The ability to nucleate calcium phosphates (CaP) after ageing 28 days in a simulated body fluid was evaluated using ESEM-EDX and micro-Raman spectroscopy. Data were statistically analysed (P = 0.05) using one-way anova (setting time, radiopacity, solubility, water sorption, porosity) or two-way anova (ion release tests). RESULTS: BioRoot RCS had a final setting time of 300 min and adequate radiopacity (5.2 mm Al). It demonstrated the highest (P < 0.05) and more prolonged ability to release calcium ions (721 ppm at 3 h) and to increase the pH (11-12) (P < 0.05); B-type carbonated apatite deposits were found on aged BioRoot RCS (biointeractivity-related CaP-forming ability). A final setting time of 270 min and good calcium release (17.4 ppm at 3 h) were measured for MTA Fillapex; apatite deposits were present on aged samples. No calcium release and no alkalizing activity were measured for Pulp Canal Sealer and AH Plus; no CaP nucleation was detected on aged Pulp Canal Sealer, and some apatite deposits were found on aged AH Plus (chemi/physisorption-related CaP-deposition). Higher and significantly different (P < 0.05) porosity, water sorption and solubility were measured for the two calcium silicate sealers, especially for BioRoot RCS. CONCLUSIONS: BioRoot RCS had bioactivity with calcium release, strong alkalizing activity and apatite-forming ability, and adequate radiopacity.

Between history and gossip: the state of women relative to syphilis, a traditionally male disease.

Despite the new World Health Organization data remind us how syphilis is a disease which affects both sexes equally, this pathology has always been mainly considered a male disease. While several famous men are known to be affected by syphilis, there are very few women affected by this pathology of which we have historical records. Through the lives of Mary Todd Lincoln, Catherine of Aragon, Karen Blixen and Florence Foster Jenkins, this article would like to grant dignity to all the women who contracted syphilis in the wrong historical era where, for a woman, admitting to contracting it was shameful. Through the important women who lived their lives fighting against this disease and its complications, we would like to pay tribute to all those women who still today, in an era of antibiotics and where syphilis is a treatable pathology, they cannot be cured because they are both geographically and socially disadvantaged.

A short novel about the spread of two important diseases in history: syphilis and SARS.

Throughout the centuries, the undefended nature of man has very often manifested in cases of epidemics, which have determined scenarios of suffering and death. Through "historical" observation lens, it is possible to understand the relationship between the spread of viruses, bacteria and parasites responsible for these epidemics and the displacement of ancient or contemporary travellers. We have analysed two infective diseases, syphilis and SARS, and their role in history and in medicine.

Properties of NeoMTA Plus and MTA Plus cements for endodontics.

AIM: To test a novel calcium silicate cement mixed with a water-based gel (NeoMTA Plus) with regard to chemical-physical properties and apatite-forming ability. METHODOLOGY: NeoMTA Plus (Avalon Biomed Inc. Bradenton, FL, USA; lot. 2014090301) and a commercial MTA-based material with similar properties (MTA Plus, Prevest Denpro Limited, Jammu, India; lot. 41001) were tested for ion-releasing ability, initial and final setting times, radiopacity, open and impervious porosity and apparent porosity, water sorption, weight loss, solubility, ability to nucleate calcium phosphates (CaP) after immersion in HBSS (Hank's Balanced Salt Solution) by ESEM-EDX and micro-Raman spectroscopy. The results were analysed statistically with the anova test (P  <  0.05). RESULTS: NeoMTA Plus had a prolonged setting time (315 min) and a satisfactory radiopacity (3.76 mm Al). Calcium and hydroxyl ion release was significantly greater and more prolonged in comparison with MTA Plus (P < 0.05). Both NeoMTA Plus and MTA Plus had high values of open porosity and solubility. ESEM-EDX and micro-Raman confirmed the ability to nucleate calcium phosphates on their surface after immersion in HBSS. CONCLUSION: NeoMTA Plus is a new calcium silicate-based cement for root filling with an adequate radiopacity and prolonged setting time. The ion release and CaP-forming ability could increase stability of the root filling and promote endodontic and periodontal tissue regeneration, enhancing the bioactivity and biocompatibility of the material.

Osteoinductive potential and bone-bonding ability of ProRoot MTA, MTA Plus and Biodentine in rabbit intramedullary model: Microchemical characterization and histological analysis.

OBJECTIVE: To study the in vivo osteoinductive potential, bone-bonding ability (bioactivity) and bone biomineralization of current hydraulic calcium silicate cements used as graft materials and placed in contact with medullary bone. METHODS: ProRoot MTA, MTA Plus and Biodentine were used to fill surgical bone defects (2-mm diameter through the entire cortical thickness to reach the medullary bone) in the tibia of mature male rabbits. Tibiae were retrieved after 30days and submitted to histological analysis and microchemical characterization using Optical Microscopy (OM) and Environmental Scanning Electron Microscopy with Energy Dispersive X-ray analysis (ESEM-EDX). Bone neoformation and histomorphometric evaluations, degree of mineralization (by Ca/P, Ca/N and P/N ratios) and the diffusion of material elements were studied. RESULTS: Bone neoformation was observed in response to all materials. No sign of necrosis were found on the walls of the pre-existing cortical bone. No osteoclasts and no formation of fibrous tissue were evident. Sign of angiogenesis were present. EDX (element content, line profile and element mapping) showed the increase in Ca and P and decrease in C, S and N from the mature bone towards the mineralizing interface. Ca/P, Ca/N and P/N ratios showed differences in the degree of mineralization/maturation stage of bone. MTA Plus and ProRoot MTA exhibited close contact with the pre-existing bone and good bone-bonding with neoformed bone juxtaposed on the medullary side of the materials without interposed connective tissue or resorption lacunae or gaps. The materials showed a dense appearance with 100% of residual materials and no colonization by fluids and cells. No migration of Bi or Al material elements to the newly formed bone was found. Biodentine showed newly formed trabecular bone with marrow spaces and sparse traces of residual material (≈9%). SIGNIFICANCE: The in vivo osteoinductive properties with dynamic biomineralization processes around these calcium silicate materials extruded in medullary bone in appropriate animal model have been demonstrated by ESEM-EDX in association with OM. Good biocompatibility was evident as only slight inflammatory infiltrate and no sign of necrosis at the interface with the pre-existing bone were found. MTA Plus and ProRoot MTA exhibited bioactive potential as they can bond to bone directly without interposed connective tissue. Biodentine was replaced by newly formed bone. CLINICAL SIGNIFICANCE: The results of the study demonstrate the capacity of calcium silicate cements to allow osteoid matrix deposition by activated osteoblasts and favour its biomineralization, and to achieve a direct bond between the (bioactive) materials surface and the mineralized bone matrix.

Structural analysis of HyFlex EDM instruments.

AIM: To compare the phase transformation behaviour, the microstructure, the nano-hardness and the surface chemistry of electro-discharge machined HyFlex EDM instruments with conventionally manufactured HyFlex CM. METHODOLOGY: New and laboratory used HyFlex EDM were examined by X-ray diffraction (XRD) and differential scanning calorimetry (DSC). Nano-hardness and modulus of elasticity were also investigated using a maximum load of 20 mN with a minimum of 40 significant indentations for each sample. Raman spectroscopy and field emission-scanning electron microscope (FE-SEM) were used to assess the surface chemistry of HyFlex EDM. HyFlex CM were subjected to the same investigations and used as a comparison. Nano-indentation data were statistically analysed using the Student's t-test. RESULTS: XRD analysis on HyFlex EDM revealed the presence of martensite and rhombohedral R-phase, while a mixture of martensite and austenite structure was identified in HyFlex CM. DSC analysis also disclosed higher austenite finish (Af) temperatures for electro-discharge machining (EDM) instruments. Significant differences in nano-hardness and modulus of elasticity were found between EDM and CM files (P < 0.05). FE-SEM and EDS analyses confirmed that both new EDM and CM files were covered by an oxide layer. Micro-Raman spectroscopy assessed the presence of rutile-TiO2 . CONCLUSIONS: HyFlex EDM revealed peculiar structural properties, such as increased phase transformation temperatures and hardness. Present results corroborated previous findings and shed light on the enhanced mechanical behaviour of these instruments.

Double dye technique and fluid filtration test to evaluate early sealing ability of an endodontic sealer.

OBJECTIVES: The aim of the present study is to evaluate the possible correlation between sealer penetration into dentinal tubules and sealing ability both in presence and absence of smear layer. MATERIALS AND METHODS: Fourteen maxillary central incisors were treated with 5.25 % NaOCl +10 % EDTA to remove the smear layer (SL-free group) or 5.25 % NaOCl without EDTA (SL group). Root canals were filled using #25 Thermafil Obturators with Topseal sealer labelled with 0.1 wt% rhodamine B. Sealing ability was measured as fluid filtration rate with a fluid-flow meter using water supplemented with 0.3 % calcein fluorescent dye. Specimens were sectioned, observed under confocal microscope to co-localize the presence of sealer (rhodamine B labelling) into dentinal tubules and gaps (calcein labelling) into the root canal. The depth of sealer penetration into dentinal tubules and the percentage of sealer penetration around the root canal were measured at 3, 5 and 8 mm from the apex. RESULTS: No significant differences between groups were observed in fluid filtration rate nor in depth of calcein penetration. Sealer penetration depth and percentage into dentinal tubules were not significantly different between groups, except at 8-mm level in absence of smear layer. CONCLUSION: Sealer penetration at 3- and 5-mm levels was not influenced by smear layer while it was significantly reduced at 8-mm level. Fluid filtration rate was not correlated either with depth of calcein penetration nor with sealer penetration into dentinal tubules. CLINICAL RELEVANCE: The sealing ability of Topseal sealer is not affected by presence or absence of smear layer.

Properties of a novel polysiloxane-guttapercha calcium silicate-bioglass-containing root canal sealer.

OBJECTIVE: Root canal filling sealers based on polymethyl hydrogensiloxane or polymethyl hydrogensiloxane-guttapercha--introduced to improve the quality of conventional guttapercha-based and resin-based systems--showed advantages in handiness and clinical application. The aim of the study was to evaluate the chemical-physical properties of a novel polysiloxane-guttapercha calcium silicate-containing root canal sealer (GuttaFlow bioseal). METHODS: GuttaFlow bioseal was examined and compared with GuttaFlow2, RoekoSeal and MTA Fillapex sealers. Setting times, open and impervious porosity and apparent porosity, water sorption, weight loss, calcium release, and alkalinizing activity were evaluated. ESEM-EDX-Raman analyses of fresh materials and after soaking in simulated body fluid were also performed. RESULTS: Marked differences were obtained among the materials. GuttaFlow bioseal showed low solubility and porosity, high water sorption, moderate calcium release and good alkalinizing activity. MTA Fillapex showed the highest calcium release, alkalinizing activity and solubility, RoekoSeal the lowest calcium release, no alkalinizing activity, very low solubility and water sorption. Only GuttaFlow bioseal showed apatite forming ability. SIGNIFICANCE: GuttaFlow bioseal showed alkalinizing activity together with negligible solubility and slight calcium release. Therefore, the notable nucleation of apatite and apatite precursors can be related to the co-operation of CaSi particles (SiOH groups) with polysiloxane (SiOSi groups). The incorporation of a calcium silicate component into polydimethyl polymethylhydrogensiloxane guttapercha sealers may represent an attractive strategy to obtain a bioactive biointeractive flowable guttapercha sealer for moist/bleeding apices with bone defects in endodontic therapy.

Mensurações do bulbo ocular e cálculo do poder dióptrico da lente intraocular em miniporcos / Ocular bulb measurements and diopter power calculation of the lens in minipigs

Objetivou-se com este trabalho determinar o poder dióptrico da lente intraocular (LIO) em miniporco e as dimensões do bulbo do olho. Foram utilizados 17 miniporcos, sadios, adultos, machos e fêmeas, com peso médio de 70kg. Em todos os olhos foram realizadas a ultrassonografia modo A, a ceratometria e a medida da distância limbo a limbo. O cálculo do poder dióptrico da LIO foi obtido utilizando-se as fórmulas Haigis, Hoffer Q, SRK/T, Holladay I e Holladay II e o software Holladay IOL Consultant(r). Na comparação entre o sexo e a lateralidade do olho, não houve diferença nas variáveis biométricas e poder da LIO. A aplicação das fórmulas (Haigis, Holladay II, Holladay I, SRK/T e Hoffer Q) possibilitou o cálculo do poder da LIO. A Holladay II, fórmula que melhor individualiza o bulbo do olho do miniporco, estima valor dióptrico ao redor de 41 D. Os miniporcos têm potencial como modelo experimental em oftalmologia, relacionado ao seu menor porte e à facilidade no manejo, especialmente em experimentos de longa duração.

The aim of this study was to determine the refractive power of intraocular lens (IOL) of mini pigs and the dimensions of the eyeball. A total of 17 (34 eyes) healthy, adult, males and female animals, with average weight of 70kg were used. For every eye, A-mode ultrasound, keratometry and the measurement of limbo-to-limbo distance were conducted, all variables for calculating the refractive power of the IOL. The value was obtained using different formulas and Holladay IOL Consultant(r) Software. Additionally, the ocular measurements were compared per sex, laterality of the eye and the different formulas used in this study (Haigis, Hoffer Q, SRK / T, Holladay I and Holladay II). In the comparison between sex and laterality of the eye, there was no difference in biometric variables and power of the IOL. The application of the employed formulas (Haigis, Holladay II, Holladay I, SRK / T and Hoffer Q) allowed the IOL power calculation for this specie, and the observed value ranged between 39.58±2.15 and 46.60±2.81 diopters. Mini pigs play an important and growing role as an experimental model for study and practice of ophthalmic procedures, specially related to their smaller size and easy management in long-term experiments.

HyFlex EDM: superficial features, metallurgical analysis and fatigue resistance of innovative electro discharge machined NiTi rotary instruments.

AIM: To evaluate the surface and microstructural alterations of new and used HyFlex EDM prototypes and to test their fatigue resistance. METHODOLOGY: Fifteen HyFlex EDM prototypes were used for in vitro instrumentation of severely curved root canals. Surface and microstructural characteristics of new and used files were compared by ESEM analysis equipped with energy dispersive X-ray spectrophotometry (EDS) and optical metallographic imaging. Usage-induced degradation was assessed. Thirty additional HyFlex EDM prototypes and 20 standard manufactured HyFlex CM files were subjected to cyclic fatigue tests. Time to fracture was recorded, and results were validated using the Kruskal-Wallis test (α-level 0.05). Fatigued files were analysed by ESEM for fractographic evaluation. RESULTS: Surface and microstructural characterization of EDM prototypes revealed the typical spark-machined surface of a NiTi EDM alloy. No fractures were registered during root canal instrumentation. No evident surface alterations and minor degradation were observed between new and used instruments. The metallographic analysis of new and used files disclosed a homogeneous structure, mostly composed of lenticular martensite grains, and some residual austenite. The cyclic fatigue test showed an increase of fatigue resistance up to 700% on the EDM compared to CM files. CONCLUSIONS: Spark-machined peculiar surface is the main feature of HyFlex EDM. Low degradation was observed after multiple canal instrumentations. Prototypes exhibited surprising high values of cyclic fatigue resistance and a safe in vitro use in severely curved canals.

Rehabilitation procedures in the management of gait disorders in the elderly.

Gait disorders are common and very disabling in elderly people, leading to an increase of risk of falling and reductions in quality of life. So far, many clinical classifications of gait disorders in the elderly population have been proposed. Here we suggest a novel categorization of gait disorders in elderly people, which takes into account the several resources required during gait. The biomechanical constraints, movement and sensory strategies, orientation in space, control of dynamics and cognitive processing are essential to perform safely gait. Moreover, the strictly connection between gait and balance has been discussed. According to this perspective, a literature search was performed including studies investigating the rehabilitation procedures in the management of balance and gait disorders in elderly people. Training aimed at improving muscle strength and flexibility, movement strategies, sensorimotor integration and sensory reweighting processes, balance in static and dynamic conditions and cognitive strategies have been proposed as possible therapeutic approaches in elderly people affected by gait disorders. Moreover, the role of new technological devices in improving balance and gait control has been also described. A multidisciplinary and interdisciplinary approach is fundamental for the management of gait disorders in elderly people. Rehabilitation procedures should take into consideration all the potential constraints involved in gait disorders in order to select the most appropriate intervention.

Calcium silicate/calcium phosphate biphasic cements for vital pulp therapy: chemical-physical properties and human pulp cells response.

OBJECTIVES: The aim was to test the properties of experimental calcium silicate/calcium phosphate biphasic cements with hydraulic properties designed for vital pulp therapy as direct pulp cap and pulpotomy. METHODS: CaSi-αTCP and CaSi-DCDP were tested for ion-releasing ability, solubility, water sorption, porosity, ability to nucleate calcium phosphates, and odontoblastic differentiation­alkaline phosphatase (ALP) and osteocalcin (OCN) upregulation­of primary human dental pulp cells (HDPCs). RESULTS: The materials showed high Ca and OH release, high open pore volume and apparent porosity, and a pronounced ability to nucleate calcium phosphates on their surface. HDPCs treated with CaSi-αTCP showed a strong upregulation of ALP and OCN genes, namely a tenfold increase for OCN and a threefold increase for ALP compared to the control cells. Conversely, CaSi-DCDP induced a pronounced OCN gene upregulation but had no effect on ALP gene regulation. CONCLUSIONS: Both cements showed high biointeractivity (release of Ca and OH ions) correlated with their marked ability to nucleate calcium phosphates. CaSi-αTCP cement proved to be a potent inducer of ALP and OCN genes as characteristic markers of mineralization processes normally poorly expressed by HDPCs. CLINICAL RELEVANCE: Calcium silicate/calcium phosphate cements appear to be attractive new materials for vital pulp therapy as they may provide odontogenic/dentinogenic chemical signals for pulp regeneration and healing, and dentin formation in regenerative endodontics.

Micro-topography and reactivity of implant surfaces: an in vitro study in simulated body fluid (SBF).

The creation of micro-textured dental implant surfaces possessing a stimulating activity represents a challenge in implant dentistry; particularly, the formation of a thin, biologically active, calcium-phosphate layer on their surface could help to strengthen the bond to the surrounding bone. The aim of the present study was to characterize in terms of macrostructure, micro-topography and reactivity in simulated body fluid (SBF), the surface of titanium (Ti) implants blasted with TiO2 particles, acid etched with hydrofluoric acid, and activated with Ca and Mg-containing nanoparticles. Sandblasted and acid-etched implants were analyzed by ESEM-EDX (environmental scanning electron microscope with energy dispersive X-ray system) to study the micromorphology of the surface and to perform elemental X-ray microanalysis (microchemical analyses) and element mapping. ESEM-EDX analyses were performed at time 0 and after a 28-day soaking period in SBF Hank's balanced salt solution (HBSS) following ISO 23317 (implants for surgery­in vitro evaluation for apatite-forming ability of implant materials). Microchemical analyses (weight % and atomic %) and element mapping were carried out to evaluate the relative element content, element distribution, and calcium/phosphorus (Ca/P) atomic ratio. Raman spectroscopy was used to assess the possible presence of impurities due to manufacturing and to investigate the phases formed upon HBSS soaking. Micro-morphological analyses showed a micro-textured, highly rough surface with microgrooves. Microchemical analyses showed compositional differences among the apical, middle, and distal thirds. The micro-Raman analyses of the as-received implant showed the presence of amorphous Ti oxide and traces of anatase, calcite, and a carbonaceous material derived from the decomposition of an organic component of lipidic nature (presumably used as lubricant). A uniform layer of Ca-poor calcium phosphates (CaPs) (Ca/P ratio <1.47) was observed after soaking in HBSS; the detection of the 961 cm⁻¹ Raman band confirms this finding. These implants showed a micro-textured surface supporting the formation of CaPs when immersed in SBF. These properties may likely favor bone anchorage and healing by stimulation of mineralizing cells.