Francesco Bassi - Academia.edu (original) (raw)
Papers by Francesco Bassi
Acta Biomaterialia, Mar 1, 2007
Glass-ceramic macroporous scaffolds for tissue engineering have been developed using a polyuretha... more Glass-ceramic macroporous scaffolds for tissue engineering have been developed using a polyurethane sponge template and bioactive glass powders. The starting glass (CEL2) belongs to the system SiO 2-P 2 O 5-CaO-MgO-Na 2 O-K 2 O and has been synthesised by a conventional melting-quenching route. A slurry of CEL2 powder, polyvinyl alcohol and water has been prepared in order to coat, by impregnation, the polymeric template. An optimised thermal treatment was then use to remove the sponge and to sinter the glass powders, leading to a glass-ceramic replica of the template. Morphological observations, image analyses, mechanical tests and in vitro tests showed that the obtained devices are good candidates as scaffolds for bone-tissue engineering, in terms of pore-size distribution, pore interconnection, surface roughness, and both bioactivity and biocompatibility. In particular, a human osteoblast cell line (MG-63) seeded onto the scaffold after a standardised preconditioning route in simulated body fluid showed a high degree of cell proliferation and a good ability to produce calcium nodules. The obtained results were enhanced by the addition of bone morphogenetic proteins after cell seeding.
Key Engineering Materials, Nov 1, 2007
Glass-ceramic scaffolds for bone grafting have been prepared using the sponge replication method ... more Glass-ceramic scaffolds for bone grafting have been prepared using the sponge replication method and a highly bioactive silica based glass belonging to the system SiO 2-P 2 O 5-CaO-MgO-Na 2 O-K 2 O (CEL2). The parameters for the sponge impregnation were optimized in order to obtain a continuous coating of the polymeric skeleton which will lead, after the polymeric phase removal, to a resistant macroporous glass-ceramic template. A complete characterization was carried out on the obtained scaffold in order to assess its morphology and specifically its porosity and the degree of pores interconnection. A human osteoblasts cells line (MG-63) was cultured onto the scaffold and the effect of stimulation with shock waves on the cell ability of colonizing the scaffold was investigated.
International Journal of Prosthodontics, Sep 1, 2013
This assignment applies to all translations of the Work as well as to preliminary display/posting... more This assignment applies to all translations of the Work as well as to preliminary display/posting of the abstract of the accepted article in electronic form before publication. If any changes in authorship (order, deletions, or additions) occur after the manuscript is submitted, agreement by all authors for such changes must be on file with the Publisher. An author's name may be removed only at his/her written request. (Note: Material prepared by employees of the US government in the course of their official duties cannot be copyrighted.
International Journal of Prosthodontics, Jul 1, 2013
International Journal of Prosthodontics, Sep 1, 2013
This assignment applies to all translations of the Work as well as to preliminary display/posting... more This assignment applies to all translations of the Work as well as to preliminary display/posting of the abstract of the accepted article in electronic form before publication. If any changes in authorship (order, deletions, or additions) occur after the manuscript is submitted, agreement by all authors for such changes must be on file with the Publisher. An author's name may be removed only at his/her written request. (Note: Material prepared by employees of the US government in the course of their official duties cannot be copyrighted.
International Journal of Prosthodontics, Sep 1, 2013
This assignment applies to all translations of the Work as well as to preliminary display/posting... more This assignment applies to all translations of the Work as well as to preliminary display/posting of the abstract of the accepted article in electronic form before publication. If any changes in authorship (order, deletions, or additions) occur after the manuscript is submitted, agreement by all authors for such changes must be on file with the Publisher. An author's name may be removed only at his/her written request. (Note: Material prepared by employees of the US government in the course of their official duties cannot be copyrighted.
Revista internacional de prótesis estomatológica, 2014
El grupo de trabajo sobre longevidad de la Oral Rehabilitation Outcomes Network (ORONet) emprendi... more El grupo de trabajo sobre longevidad de la Oral Rehabilitation Outcomes Network (ORONet) emprendio una investigacion bibliografica de 1995 a 2009 sobre los ensayos controlados aleatorizados relacionados con la longevidad de los implantes osteointegrados. Se identificaron las medidas de desenlace utilizadas en estos estudios y se sometieron a los criterios compuestos de OMERACT de validez, fiabilidad y viabilidad. A traves de este proceso, fue muy complicado identificar las medidas de resultado clinico que cumplian completamente estos criterios. Se aplico una version abreviada de los criterios compuestos y se identificaron medidas clinicas para los parametros implantologicos y protesicos y los indices. Asimismo, para una futura consideracion, se presentaron recomendaciones en cuanto a los periodos estandarizados para los informes. El objetivo del proceso de evaluacion es desarrollar un consenso de las medidas de resultado clinico que puedan ser aplicadas a amplias poblaciones en los procedimientos de implantologia osteointegrada. La presente iniciativa de ORONet representa un principio hacia una mejora continuada y el desarrollo de un consenso en cuanto a las medidas de resultado para los implantes osteointegrados.
International Journal of Prosthodontics, Jul 1, 2013
This assignment applies to all translations of the Work as well as to preliminary display/posting... more This assignment applies to all translations of the Work as well as to preliminary display/posting of the abstract of the accepted article in electronic form before publication. If any changes in authorship (order, deletions, or additions) occur after the manuscript is submitted, agreement by all authors for such changes must be on file with the Publisher. An author's name may be removed only at his/her written request. (Note: Material prepared by employees of the US government in the course of their official duties cannot be copyrighted.
Oral Health & Dental Science, 2018
Revista Internacional De Protesis Estomatologica, 2014
La bibliografia publicada sobre las evidencias clinicas aplicadas en la toma de decisiones al tra... more La bibliografia publicada sobre las evidencias clinicas aplicadas en la toma de decisiones al tratar la perdida dental sigue caracterizandose por una falta de medidas de desenlace homogeneas que no solo reflejen el rendimiento clinico, sino tambien una serie de aspectos de interes para el paciente. Una vez reconocido este problema, un grupo internacional de clinicos, docentes y cientificos enfocados a la prostodoncia crearon ORONet (Oral Rehabilitation Outcomes Network, que traducido vendria a significar Red para la determinacion de parametros en la rehabilitacion oral) con el proposito de promocionar estrategias con las que mejorar la salud basandose en evaluaciones integrales que comparen la eficacia de los tratamientos de rehabilitacion oral y esten centradas en los pacientes. Uno de los objetivos iniciales de ORONet es identificar medidas de desenlace de los tratamientos prostodoncicos que representen multiples areas con relevancia para el paciente, puedan utilizarse tanto en entornos institucionales como en la consulta clinica y tengan una validez establecida. El grupo se adhirio a un modelo utilizado en reumatologia, para evaluar la bibliografia prostodoncica con enfasis en los tratamientos implatologicos, examinado los parametros relacionados con la longevidad y las esferas funcionales, psicologicas y economicas. Estas revisiones sistematicas evidencian la necesidad de un mayor desarrollo de parametros estandarizados o consensuados que puedan ser integrados en los ambitos clinicos y de investigacion.
Dental Materials, 2014
ABSTRACT Objectives: Aim of this study was to evaluate, by means of a non-destructive procedure, ... more ABSTRACT Objectives: Aim of this study was to evaluate, by means of a non-destructive procedure, the degree of conversion (DC) of two different composite cements. Subsequently, the same samples underwent a push-out test to investigate the bond strength at the adhesive interface after DC microRaman evaluation. Methods: 24 single-rooted teeth were cut at the CEJ, endodontically treated and a 8mm post-space deep was made. Teeth were randomly divided in two groups (n=12) and RelyX Fiber Posts were luted using 2 composite cements: Multilink Automix (group A/control) and an experimental cement (group B/self-adhesive). Composites were cured (120s, 400mW/cm2) and each sample was cut, perpendicularly to the long axis, in 2mm-thick slices starting from the CEJ. The sections corresponding to 1mm, 3mm, 5mm were analysed with the microRaman spectrometer; then a push-out test evaluated the resistance to the displacement of the post. Finally the slices were analysed with an optical microscope to evaluate the nature of failure. Data were statistically evaluated (ANOVA, Tukey’s, p<0.05). Results: In group A we recorded higher strength at debonding (p<0.001) and higher DC (p<0.001) compared to group B. In both groups push-out strength was higher at 1mm than at 5mm (p=0.002). Most common failures (POF) are recorded at the cement-dentin interface. Group B didn’t show any POF at cement-post interface. Conclusions: an experimental cement self-adhesive showed a lower DC and a lower bond strength compared to the “traditional technique” composite (group A). Distance from the CEJ didn’t affect the DC, due to autopolymerizing component of both materials.
Dental Materials, 2014
The objectives of the present study were (1) to determine the subcritical crack growth parameters... more The objectives of the present study were (1) to determine the subcritical crack growth parameters of an yttria partially stabilized tetragonal zirconia ceramic (Y-TZP), using the step-stress method and (2) to appoint the most precise way of estimating reliability for fatigue data. Methods and materials: Bar-shaped specimens with final dimensions of 25 mm × 4 mm × 3 mm were cut from a Y-TZP block (Vita In-Ceram YZ, Vita Zahnfabrik) using a precision saw and were sintered following the manufacturer's instructions. The specimens were subjected to cyclic fatigue (R = 0.1, 2 Hz) at various stress amplitudes using a four-point fexure fixture in DI water at 37 • C. The fatigue lifetime data were fit to an Inverse Power Law-Weibull model to obtain the SCG parameters (n and-ln K) using ALTA PRO software. The peak stresses corresponding to a failure probability of 5 and 63% at 2 M cycles, the lifetime corresponding to a failure probability of 5 and 63% at a peak stress of 80 MPa, and the probability of failure corresponding to 80 MPa for 2 M cycles were predicted using the ALTA PRO software. Results: The crack growth coefficient (−ln K) was 192.8 (124.2-261.4), n was 29 (18-40), lifetime Weibull modulus (m) was 0.21 (0.16-0.28) with 95% confidence interval. Table 1 includes stress level, lifetime and probability of failure for the studied material. Conclusion: The SCG parameters and confidence intervals can be estimated using the IPL-Weibull model from step-stress data and the most precise way to estimate reliability for fatigue data is the peak stress corresponding to 63% probability of failure (S max , 63%).
Dental Materials, 2014
ABSTRACT OBJECTIVES: The aim of this study was to evaluate the adhesive interface of a new self-a... more ABSTRACT OBJECTIVES: The aim of this study was to evaluate the adhesive interface of a new self-adhesive material used for fiber post cementation, studying the macrostructural aspect of adhesive interface after thermocycling METHODS: 10 single-rooted teeth were endodontically treated and sectioned at CEJ, then the post space was prepared and in each tooth a Relyx Fiber Post size 2 (3M-ESPE, Seefeld, Germany) was luted by means of the new experimental composite SF Cem-44 applied by means of the dedicatd elongation tip. Each root was cut into 4 slices at increasing distance from CEJ (1-3-5-7 mm), then analyzed after thermocycling (ISO/TS11405:2003) and immersion in a 2% methylene-blue (24h). The null-hypothesis is an absence of dye infiltration or voids after thermocycling. After the image steromicroscope acquisition (13x), the macrostructural analysis exploited a digital automated software (Jmicrovision), in order to assess the extent of the dye of infiltration, presence of guttapercha, micro or macrovoids. RESULTS: No voids or micro-bubbles were assessed, since the self-mixing application system and the endo-tip ensure no air bubbles within the material. We observed no dye infiltration in every slice. CONCLUSIONS: The new experimental material seem to be an acceptable and fast luting agent for post cementation, if used correctly.
PubMed, Sep 1, 1998
Advantages and disadvantages of metal-ceramic and all-ceramic restorations are reviewed particula... more Advantages and disadvantages of metal-ceramic and all-ceramic restorations are reviewed particularly from the aesthetic point of view. All-ceramic restorations offer the best results because they let the light through optimally. In constructing all-ceramic crowns on teeth which have been endodontically treated, the material used to rebuild the pin-abutments must be taken into consideration if the best aesthetic results are to be achieved. Materials which, because of their translucent characteristics, are the most aesthetic alternatives to metal alloy pin-abutments in rebuilding teeth which have been endodontically treated, are then described.
Acta Biomaterialia, Mar 1, 2007
Glass-ceramic macroporous scaffolds for tissue engineering have been developed using a polyuretha... more Glass-ceramic macroporous scaffolds for tissue engineering have been developed using a polyurethane sponge template and bioactive glass powders. The starting glass (CEL2) belongs to the system SiO 2-P 2 O 5-CaO-MgO-Na 2 O-K 2 O and has been synthesised by a conventional melting-quenching route. A slurry of CEL2 powder, polyvinyl alcohol and water has been prepared in order to coat, by impregnation, the polymeric template. An optimised thermal treatment was then use to remove the sponge and to sinter the glass powders, leading to a glass-ceramic replica of the template. Morphological observations, image analyses, mechanical tests and in vitro tests showed that the obtained devices are good candidates as scaffolds for bone-tissue engineering, in terms of pore-size distribution, pore interconnection, surface roughness, and both bioactivity and biocompatibility. In particular, a human osteoblast cell line (MG-63) seeded onto the scaffold after a standardised preconditioning route in simulated body fluid showed a high degree of cell proliferation and a good ability to produce calcium nodules. The obtained results were enhanced by the addition of bone morphogenetic proteins after cell seeding.
Key Engineering Materials, Nov 1, 2007
Glass-ceramic scaffolds for bone grafting have been prepared using the sponge replication method ... more Glass-ceramic scaffolds for bone grafting have been prepared using the sponge replication method and a highly bioactive silica based glass belonging to the system SiO 2-P 2 O 5-CaO-MgO-Na 2 O-K 2 O (CEL2). The parameters for the sponge impregnation were optimized in order to obtain a continuous coating of the polymeric skeleton which will lead, after the polymeric phase removal, to a resistant macroporous glass-ceramic template. A complete characterization was carried out on the obtained scaffold in order to assess its morphology and specifically its porosity and the degree of pores interconnection. A human osteoblasts cells line (MG-63) was cultured onto the scaffold and the effect of stimulation with shock waves on the cell ability of colonizing the scaffold was investigated.
International Journal of Prosthodontics, Sep 1, 2013
This assignment applies to all translations of the Work as well as to preliminary display/posting... more This assignment applies to all translations of the Work as well as to preliminary display/posting of the abstract of the accepted article in electronic form before publication. If any changes in authorship (order, deletions, or additions) occur after the manuscript is submitted, agreement by all authors for such changes must be on file with the Publisher. An author's name may be removed only at his/her written request. (Note: Material prepared by employees of the US government in the course of their official duties cannot be copyrighted.
International Journal of Prosthodontics, Jul 1, 2013
International Journal of Prosthodontics, Sep 1, 2013
This assignment applies to all translations of the Work as well as to preliminary display/posting... more This assignment applies to all translations of the Work as well as to preliminary display/posting of the abstract of the accepted article in electronic form before publication. If any changes in authorship (order, deletions, or additions) occur after the manuscript is submitted, agreement by all authors for such changes must be on file with the Publisher. An author's name may be removed only at his/her written request. (Note: Material prepared by employees of the US government in the course of their official duties cannot be copyrighted.
International Journal of Prosthodontics, Sep 1, 2013
This assignment applies to all translations of the Work as well as to preliminary display/posting... more This assignment applies to all translations of the Work as well as to preliminary display/posting of the abstract of the accepted article in electronic form before publication. If any changes in authorship (order, deletions, or additions) occur after the manuscript is submitted, agreement by all authors for such changes must be on file with the Publisher. An author's name may be removed only at his/her written request. (Note: Material prepared by employees of the US government in the course of their official duties cannot be copyrighted.
Revista internacional de prótesis estomatológica, 2014
El grupo de trabajo sobre longevidad de la Oral Rehabilitation Outcomes Network (ORONet) emprendi... more El grupo de trabajo sobre longevidad de la Oral Rehabilitation Outcomes Network (ORONet) emprendio una investigacion bibliografica de 1995 a 2009 sobre los ensayos controlados aleatorizados relacionados con la longevidad de los implantes osteointegrados. Se identificaron las medidas de desenlace utilizadas en estos estudios y se sometieron a los criterios compuestos de OMERACT de validez, fiabilidad y viabilidad. A traves de este proceso, fue muy complicado identificar las medidas de resultado clinico que cumplian completamente estos criterios. Se aplico una version abreviada de los criterios compuestos y se identificaron medidas clinicas para los parametros implantologicos y protesicos y los indices. Asimismo, para una futura consideracion, se presentaron recomendaciones en cuanto a los periodos estandarizados para los informes. El objetivo del proceso de evaluacion es desarrollar un consenso de las medidas de resultado clinico que puedan ser aplicadas a amplias poblaciones en los procedimientos de implantologia osteointegrada. La presente iniciativa de ORONet representa un principio hacia una mejora continuada y el desarrollo de un consenso en cuanto a las medidas de resultado para los implantes osteointegrados.
International Journal of Prosthodontics, Jul 1, 2013
This assignment applies to all translations of the Work as well as to preliminary display/posting... more This assignment applies to all translations of the Work as well as to preliminary display/posting of the abstract of the accepted article in electronic form before publication. If any changes in authorship (order, deletions, or additions) occur after the manuscript is submitted, agreement by all authors for such changes must be on file with the Publisher. An author's name may be removed only at his/her written request. (Note: Material prepared by employees of the US government in the course of their official duties cannot be copyrighted.
Oral Health & Dental Science, 2018
Revista Internacional De Protesis Estomatologica, 2014
La bibliografia publicada sobre las evidencias clinicas aplicadas en la toma de decisiones al tra... more La bibliografia publicada sobre las evidencias clinicas aplicadas en la toma de decisiones al tratar la perdida dental sigue caracterizandose por una falta de medidas de desenlace homogeneas que no solo reflejen el rendimiento clinico, sino tambien una serie de aspectos de interes para el paciente. Una vez reconocido este problema, un grupo internacional de clinicos, docentes y cientificos enfocados a la prostodoncia crearon ORONet (Oral Rehabilitation Outcomes Network, que traducido vendria a significar Red para la determinacion de parametros en la rehabilitacion oral) con el proposito de promocionar estrategias con las que mejorar la salud basandose en evaluaciones integrales que comparen la eficacia de los tratamientos de rehabilitacion oral y esten centradas en los pacientes. Uno de los objetivos iniciales de ORONet es identificar medidas de desenlace de los tratamientos prostodoncicos que representen multiples areas con relevancia para el paciente, puedan utilizarse tanto en entornos institucionales como en la consulta clinica y tengan una validez establecida. El grupo se adhirio a un modelo utilizado en reumatologia, para evaluar la bibliografia prostodoncica con enfasis en los tratamientos implatologicos, examinado los parametros relacionados con la longevidad y las esferas funcionales, psicologicas y economicas. Estas revisiones sistematicas evidencian la necesidad de un mayor desarrollo de parametros estandarizados o consensuados que puedan ser integrados en los ambitos clinicos y de investigacion.
Dental Materials, 2014
ABSTRACT Objectives: Aim of this study was to evaluate, by means of a non-destructive procedure, ... more ABSTRACT Objectives: Aim of this study was to evaluate, by means of a non-destructive procedure, the degree of conversion (DC) of two different composite cements. Subsequently, the same samples underwent a push-out test to investigate the bond strength at the adhesive interface after DC microRaman evaluation. Methods: 24 single-rooted teeth were cut at the CEJ, endodontically treated and a 8mm post-space deep was made. Teeth were randomly divided in two groups (n=12) and RelyX Fiber Posts were luted using 2 composite cements: Multilink Automix (group A/control) and an experimental cement (group B/self-adhesive). Composites were cured (120s, 400mW/cm2) and each sample was cut, perpendicularly to the long axis, in 2mm-thick slices starting from the CEJ. The sections corresponding to 1mm, 3mm, 5mm were analysed with the microRaman spectrometer; then a push-out test evaluated the resistance to the displacement of the post. Finally the slices were analysed with an optical microscope to evaluate the nature of failure. Data were statistically evaluated (ANOVA, Tukey’s, p<0.05). Results: In group A we recorded higher strength at debonding (p<0.001) and higher DC (p<0.001) compared to group B. In both groups push-out strength was higher at 1mm than at 5mm (p=0.002). Most common failures (POF) are recorded at the cement-dentin interface. Group B didn’t show any POF at cement-post interface. Conclusions: an experimental cement self-adhesive showed a lower DC and a lower bond strength compared to the “traditional technique” composite (group A). Distance from the CEJ didn’t affect the DC, due to autopolymerizing component of both materials.
Dental Materials, 2014
The objectives of the present study were (1) to determine the subcritical crack growth parameters... more The objectives of the present study were (1) to determine the subcritical crack growth parameters of an yttria partially stabilized tetragonal zirconia ceramic (Y-TZP), using the step-stress method and (2) to appoint the most precise way of estimating reliability for fatigue data. Methods and materials: Bar-shaped specimens with final dimensions of 25 mm × 4 mm × 3 mm were cut from a Y-TZP block (Vita In-Ceram YZ, Vita Zahnfabrik) using a precision saw and were sintered following the manufacturer's instructions. The specimens were subjected to cyclic fatigue (R = 0.1, 2 Hz) at various stress amplitudes using a four-point fexure fixture in DI water at 37 • C. The fatigue lifetime data were fit to an Inverse Power Law-Weibull model to obtain the SCG parameters (n and-ln K) using ALTA PRO software. The peak stresses corresponding to a failure probability of 5 and 63% at 2 M cycles, the lifetime corresponding to a failure probability of 5 and 63% at a peak stress of 80 MPa, and the probability of failure corresponding to 80 MPa for 2 M cycles were predicted using the ALTA PRO software. Results: The crack growth coefficient (−ln K) was 192.8 (124.2-261.4), n was 29 (18-40), lifetime Weibull modulus (m) was 0.21 (0.16-0.28) with 95% confidence interval. Table 1 includes stress level, lifetime and probability of failure for the studied material. Conclusion: The SCG parameters and confidence intervals can be estimated using the IPL-Weibull model from step-stress data and the most precise way to estimate reliability for fatigue data is the peak stress corresponding to 63% probability of failure (S max , 63%).
Dental Materials, 2014
ABSTRACT OBJECTIVES: The aim of this study was to evaluate the adhesive interface of a new self-a... more ABSTRACT OBJECTIVES: The aim of this study was to evaluate the adhesive interface of a new self-adhesive material used for fiber post cementation, studying the macrostructural aspect of adhesive interface after thermocycling METHODS: 10 single-rooted teeth were endodontically treated and sectioned at CEJ, then the post space was prepared and in each tooth a Relyx Fiber Post size 2 (3M-ESPE, Seefeld, Germany) was luted by means of the new experimental composite SF Cem-44 applied by means of the dedicatd elongation tip. Each root was cut into 4 slices at increasing distance from CEJ (1-3-5-7 mm), then analyzed after thermocycling (ISO/TS11405:2003) and immersion in a 2% methylene-blue (24h). The null-hypothesis is an absence of dye infiltration or voids after thermocycling. After the image steromicroscope acquisition (13x), the macrostructural analysis exploited a digital automated software (Jmicrovision), in order to assess the extent of the dye of infiltration, presence of guttapercha, micro or macrovoids. RESULTS: No voids or micro-bubbles were assessed, since the self-mixing application system and the endo-tip ensure no air bubbles within the material. We observed no dye infiltration in every slice. CONCLUSIONS: The new experimental material seem to be an acceptable and fast luting agent for post cementation, if used correctly.
PubMed, Sep 1, 1998
Advantages and disadvantages of metal-ceramic and all-ceramic restorations are reviewed particula... more Advantages and disadvantages of metal-ceramic and all-ceramic restorations are reviewed particularly from the aesthetic point of view. All-ceramic restorations offer the best results because they let the light through optimally. In constructing all-ceramic crowns on teeth which have been endodontically treated, the material used to rebuild the pin-abutments must be taken into consideration if the best aesthetic results are to be achieved. Materials which, because of their translucent characteristics, are the most aesthetic alternatives to metal alloy pin-abutments in rebuilding teeth which have been endodontically treated, are then described.