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Tissue integration of biomaterials can be increased by several modifications at the nanoscale: we explored surface texturing (topography at the nanoscale), structuring (microstructure at the nanoscale) and nanofiber deposition. Nano-texturing of the surface can be useful to get bioactive behaviour and mineralization ability (apatite precipitation) on titanium alloys, as well as better cell differentiation for osseointegration, enhanced cell proliferation and contact guidance effect on soft tissues, tailored inflammatory response. Both nano-texturing and -structuring can reduce bacteria adhesion and biofilm formation. We tested nano-textured titanium obtained both through chemical and e-beam surface treatments. The first shows nano-porous and isotropic topography and modified surface chemistry (degree of hydroxylation). In this way, the integration of the implant to the hard or soft tissues can be increased and inflammatory response as well as adhesion of bacteria can be reduced. On the other side, e-beam surface directional texturing (grooves) can be useful for contact guidance effect on fibroblasts and reduced adhesion of bacteria because of a refinement of the microstructure (nano-structuring). Also, nanofiber deposition can be useful in order to enhance soft tissues adhesion (e.g. gum) and to direct fibroblasts into a specific direction. We tested both random and oriented keratin nanofibers. Biological (bacterial and cell cultures) and chemical characterization (FTIR, XPS, FESEM, EDS, zeta potential) of the modified surfaces is described. All the obtained results are discussed to get an overall understanding of the potential applications of biomaterials surfaces modified at the nanoscale with a focus on the dental and orthopaedic implants.

This review aims to describe trigeminal neuralgia and the molecular basis contributing to the pathophysiology of this condition by focusing on the state of the art.An electronic search of PubMed was performed using the following keywords: "trigeminal neuralgia" AND "classification", "pathophysiology," "molecular basis" and "mitochondrial role."Mitochondrial abnormality, whether functional or morphological, can contribute to neurological disorders. Additionally, one recent finding showed that gain-of-function mutation in the voltage-gated sodium channel NaV1.6 contributes to the pathophysiology of trigeminal neuralgia by increasing the excitability of trigeminal nerve ganglion neurons. It also exacerbates the pathophysiology of vascular compression. Healing of the trigeminal nerve is controlled by many molecular signaling pathways, including extracellular-signal-regulated kinase, c-Jun, p38, Notch, and mitogen-activated protein kinases.More investigations regarding the gain-of-function mutation of NaV1.6 sodium channels are essential for the diagnosis and treatment of trigeminal nerve disorders, regardless of whether these are associated with vascular compression or not.

Introduction: Despite of wide research on surface modifications of the titanium implants for bone contact applications, a relatively low number of works consider interaction between the titanium surfaces and soft tissues. However, this topic is of interest in several cases, such as the transmucosal dental and percutaneous orthopedic implants. The rationale of this research follows the following fundamental principles of surface engineering. Topography and roughness play a crucial role both in bacterial and cell adhesion, moreover specific chemical and biological stimuli can be sent to the cells in order to modulate the biological response to the implants. A lower Ra limit of 0.2 µm has been defined in literature in order to avoid an increased bacterial contamination [1]. In the case of soft tissues, fibroblasts preferentially adhere on polished substrates and can be guided by surface grooves [2]. Keratin has a well-known action of chemical stimulus on fibroblasts. On this basis, the specific aim of this research work is to modify titanium surfaces by means of nanogrooves and keratin nanofibers, in order to drive gingival fibroblasts alignment and proliferation through topographical and chemical stimuli without increasing bacterial adhesion. Material and Methods: Oriented nanogrooves were obtained on c.p. titanium by a mechanical route (specific polishing protocol) or by means of Electron Beam Welding (EBW) paying attention to keep the final surface roughness lower than 0.2 µm. Keratin was extracted from wool and nanofibers were deposited onto mirror polished or roughened titanium substrates by electrospinning both as fibers randomly oriented or aligned to the grooves. The viability and orientation of human gingival fibroblasts were investigated on the modified surfaces together with bacterial (S. aureus) adhesion and biofilm formation.Results and Discussion: Oriented nanogrooves (Ra 0.1-0.2 µm) were successfully obtained on titanium substrates both by mechanical and EBW routes. Keratin nanofibers were deposited on the titanium surfaces without significantly altering surface roughness and they resulted stable up to 1 month of soaking in water. Gingival fibroblasts were able to adhere and to get a specific orientation along the grooves and they show to be positively sensitive to the presence of keratin (improved proliferation). None of the tested surfaces increased bacterial adhesion compared to a mirror polished control. Conclusion: The findings of this study suggest nanogrooves and keratin nanofibers as promising modification strategies for the surface of transmucosal dental implants in the collar region in order to obtain an effective gum sealing and reduce bacterial penetration. Moreover, the proposed strategy supports byproduct recycling and is in line with a sustainable employment of resources.

Riassunto Obiettivi Valutare l’efficacia di due presidi monouso per l’igiene oro-dentale personale. Materiali e metodi Studio sperimentale controllato condotto su un campione di giovani adulti sani suddivisi casualmente in un gruppo test, che ha utilizzato i due presidi monouso (spazzolino in polietilene a bassa densita, spugnetta), e un gruppo di controllo, che ha usato uno spazzolino tradizionale. Due operatori calibrati hanno rilevato l’indice di placca secondo Dababneh (NMPS) e l’indice gengivale secondo Loe e Sillness (GI) all’inizio della sperimentazione (T0) e dopo 48 ore (T1). Risultati Nel gruppo test dopo 48 ore si e osservato un incremento significativo dell’indice di placca tra gli utilizzatori dei presidi monouso, minore per gli utilizzatori dello spazzolino monouso (p ≤ 0,002; spugnetta p ≤ 0,001) rispetto al gruppo di controllo (ANOVA a una via). Conclusioni L’impiego dello spazzolino monouso e da preferirsi a quello della spugnetta monouso.

In orthopaedic surgery the tissues damaged by injury or disease could be replaced using constructs based on biocompatible materials, cells and growth factors. Scaffold design, porosity and early colonization are key components for the implant success. From biological point of view, attention may be also given to the number, type and size of seeded cells, as well as the seeding technique and cell morphological and volumetric alterations. This paper describes the use of the microCT approach (to date used principally for mineralized matrix quantification) to observe construct colonization in terms of cell localization, and make a direct comparison of the microtomographic sections with scanning electron microscopy images and confocal laser scanning microscope analysis. Briefly, polycaprolactone scaffolds were seeded at different cell densities with MG63 osteoblastic-like cells. Two different endpoints, 1 and 2 weeks, were selected for the three-dimensional colonization and proliferation analysis of the cells. By observing all images obtained, in addition to a more extensive distribution of cells on scaffolds surfaces than in the deeper layers, cell volume increased at 2 weeks compared to 1 week after seeding. Combining the cell number quantification by deoxyribonucleic acid analysis and the single cell volume changes by confocal laser scanning microscope, we validated the microCT segmentation method by finding no statistical differences in the evaluation of the cell volume fraction of the scaffold. Furthermore, the morphological results of this study suggest that an effective scaffold colonization requires a precise balance between different factors, such as number, type and size of seeded cells in addition to scaffold porosity.

Titanium and titanium alloys are widely used in dental and orthopaedic implants, because of their biocompatibility, corrosion resistance and mechanical performance. Tissue integration of Ti based materials can be increased by several modification at the nanoscale: we explored nanoparticles precipitation, nanostructuring of the surface and nanofiber deposition in this research. Nanoparticle precipitation can be useful in order to add antibacterial agents onto the titanium surface: silver nanoparticles were investigated in this research. Silver nanoparticles precipitation was obtained by different processes and antibacterial activity / ion release were monitored for different times[2]. Nano-structuring of the titanium surface can be useful in order to get bioactive behaviour and mineralization ability (apatite precipitation) of the surface, as well as better cell differentiation (osteoblasts). In this way, the integration of the implant to the hard tissue can be increased because of a faster growth of inorganic (apatite) and biological (osteoblasts) components of bone. Nanostructured titanium shows a peculiar topography and surface chemistry (e.g. zeta potential). In-vitro apatite precipitation and cell response were tested on smooth and nanostructured titanium surfaces[1]. Nanofiber deposition of biomolecules can be useful in order to enhance soft tissues adhesion (e.g. gum), to direct fibroblasts into a specific direction and to get a biomimetic material. Biological (bacterial and cell cultures) and chemical tests (FTIR, XPS, FESEM , EDS, zeta potential) of the modified surfaces through nanofiber deposition were performed. All the obtained results are discussed in order to get an overall understanding of the potential applications of titanium surfaces modified at the nanoscale in the dental and orthopaedic implants.

Research at the interface between bioengineering and nanotechnology presents exciting opportunities for creating novel materials that can have a significant impact, both scientifically and commercially. This new field is characterized by its multidisciplinary nature, cutting across science, engineering and medicine. This work describes how research in biomaterials and nanotechnology comes together to bring about novel materials and processes to tackle challenges in drug delivery, protein adsorption, tissue engineering, artificial implants and nanobiotechnology. It discusses the importance of designing nanoscale features and in particular surface reactivity for deriving unique systems with tailored properties, and illustrates the significance of controlling multiple length scales in fabricating hierarchical structures, and the flexibility of nanocomposite processing in creating complex materials with multiple functionalities.

Brevettazione della sintesi industriale di carbonato-idrossiapatite zinco sostituita da utilizzare come principio attivo in paste dentifrice aventi la capacità di rimineralizzare lo smalto dentale

In orthopaedic surgery the tissues damaged by injury or disease could be replaced using constructs based on biocompatible materials, cells and growth factors. Scaffold design, porosity and early colonization are key components for the implant success. From biological point of view, attention may be also given to the number, type and size of seeded cells, as well as the seeding technique and cell morphological and volumetric alterations. This paper describes the use of the microCT approach (to date used principally for mineralized matrix quantification) to observe construct colonization in terms of cell localization, and make a direct comparison of the microtomographic sections with scanning electron microscopy images and confocal laser scanning microscope analysis. Briefly, polycaprolactone scaffolds were seeded at different cell densities with MG63 osteoblastic-like cells. Two different endpoints, 1 and 2 weeks, were selected for the three-dimensional colonization and proliferation analysis of the cells. By observing all images obtained, in addition to a more extensive distribution of cells on scaffolds surfaces than in the deeper layers, cell volume increased at 2 weeks compared to 1 week after seeding. Combining the cell number quantification by deoxyribonucleic acid analysis and the single cell volume changes by confocal laser scanning microscope, we validated the microCT segmentation method by finding no statistical differences in the evaluation of the cell volume fraction of the scaffold. Furthermore, the morphological results of this study suggest that an effective scaffold colonization requires a precise balance between different factors, such as number, type and size of seeded cells in addition to scaffold porosity.

The causes of bad breath are numerous and related to conditions dependent or not on oral and general health. The aim of our observational study is the assessment of the simultaneous relationships between halitosis, oral and/or nonoral diseases, and lifestyles using the principal components analysis of categorical data (CATPCA) to identify the main components involved in the detection of the symptom.A sample of 192 patients, who requested general dental examination at the Dental Clinic, participated at the study. Alimentary and voluptuary habits, general health information, drugs assumption, the status of teeth and intraoral medical devices including fillers, lesions of the oral mucosa, tongue coating score (TCS), plaque index (PI), probing bleeding index (PBI) and organoleptic tests were all evaluated. Data were analysed using CATPCA model.A strong relationship between halitosis and plaque, probing bleeding and tongue coating indexes was observed, whereas incongruous fillers, prostheses, systemic pathologies or diet were not clearly associated with halitosis probably because their effects on breath were clinically sheltered by the periodontal condition.The data of our observational study confirm that halitosis is more indicative of tongue coating and periodontal disease, rather than other oral and non oral associated conditions, like systemic pathologies or specific habits of life.

The periodontal ligament (PDL) has been found to house progenitor elements which may give rise to a new periodontium when properly triggered. Complex molecular mechanisms are involved in guiding such cells towards their final regenerative task. Hyaluronan (HA), an extracellular matrix molecule abundantly present during early tissue development, is usually found at high concentrations in all adult mammalian PDL tissue. In this study, PDL cells were cultured on HA coated experimental plastic Petri's dishes (E.D.) and mineralized-nodules formation, at the microscopical level, was evaluated in comparison to HA-free control dishes (C.D.) after 21 days. Little colony formation occurred in presence of HA, whereas CD showed normal cell confluence with mineralization of nodules even at 10 days. However, when harvesting was performed from both dishes after only 12 hours, before cell aggregation occurred, cell confluence and nodule formation could be seen with no apparent difference between test and control. This study shows that, with respect to PDL cells, hyaluronan seems to inhibit cell adhesion, although with no interference with cell aggregates calcifying potentials. This latter finding may: a) provide further insight in analyzing the properties of extracellular matrix substrates in the PDL environment, b)guide research to possible explanations on how the PDL maintains its characteristics of uncalcified tissue and c) lead to theorize regarding utilization in tissue regeneration. (Journal of Applied BiomaterialBiomechanics 2003; 1: 84-90).

The increasing use of biomaterials and medical devices has led to the development of new families of diseases related precisely to the use of the biomaterials and medical devices themselves. Microbial contamination of the devices is a serious and widespread problem in surgery because it often causes devastating infections and loss of the implanted devices. The methods of contamination in medical devices are dependent on many peculiar factors including the chemistry of the biomaterial, the physical properties of the surface, the design of the medical device, the implanted anatomical site, the extension of surgical invasion, and the time of application. The environment and/or conditions and response of the host also contribute to the development of the colonization and infection. Many bacteria and fungi spp. are involved in biomaterial infections, but most belong to endogenous bacteria or the commensal community of the skin such as Staphylococcus epidermidis and Staphylococcus aureus. Medical device contamination always develops into biofilm formation, which constitutes a protected mode for the bacteria to survive in a hostile environment by optimizing nutrient uptake, as it is sheltered from the removal forces and is protected from the host defense mechanism and from potential toxic or harmful substances including antibiotics. Therefore, studies concerning infections related to implanted materials are of increasing frequency and interest. Both in vitro and in vivo studies are reported to simulate biomaterial infection. We report suggestions concerning useful standards and strategies to re-duce contamination on biomaterials. (Journal of Applied Biomaterials and Biomechanics 2005; 3: 1-10).

This paper evaluated the efficacy of the systemic administration of levosulpiride, an antipsychotic and antidepressant drug, in the management of burning mouth syndrome.Forty-four subjects suffering from idiopathic burning mouth syndrome were enrolled in the study. Patients underwent a thorough clinical examination, including salivary flow rate measurements, laboratory tests (complete blood cell counts, blood glucose levels, serum iron and transferrin levels, serum vitamin B(12), and folate levels), patch tests for contact allergy to denture materials, and isolation of Candida species from oral mucosal scrapes. Oral symptoms before and after treatment were assessed using a visual analogue scale. All the patients used systemic levosulpiride (100 mg/daily) for 8 weeks.Of the 39 patients who completed the protocol, none reported complete remission of the oral burning sensation. However, 28 patients reported at least some improvement, and these patients had had oral symptoms for significantly less time than those who reported no improvement.These preliminary data suggest that levosulpiride is more effective in patients who have recently developed burning/stinging oral sensation.

Early extraction of carious primary teeth may result in functional and/or loss of arch length problems. That is the rationale behind root canal therapy and/or space maintenance after the extraction of pulpally involved primary molars. What follows is a short radiographic and photographic history of unexpected results in well established and routine space therapy treatments.

Correct endodontic treatments will be produced if the quality control of intra-operatory dental roentgengraphic displays an adequate periapical coverage. The degree of anatomic accuracy of Rx images depends on correct technical procedure which includes exposure, angulation, object-film and focal-film distance. According to many Authors only the paralleling extended-distance technique provides the minimum of dimensional distortion.

Restorative treatment of largely destroyed first permanent molars in the mixed dentition involves a few peculiar considerations. Special attention must be given to the restorative-periodontal relationship.

Nanosized carbonate-hydroxyapatite represents a suitable material for bone substitution and delivery of biomolecules. Its interaction with serum proteins plays a central role in the process of implantation of a device. Herein, surface interactions of human (HSA) and bovine (BSA) serum albumin with two biomimetic carbonate-hydroxyapatites (CHA) differing for size, surface area, crystallinity degree and surface properties have been investigated. BSA reached a different maximum coverage, being higher with the CHA nanocrystals with the higher surface area, the smaller size, the lower crystallinity degree and the plate shape morphology. On the contrary, HSA did not show significant differences of maximum coverage on the two substrates. The adsorption isotherms have been fitted by the Langmuir and Freundlich models, showing that the biomimetic hydroxyapatite matrix behaves as a mixture of energetically homogeneous and heterogeneous sites due to its surface disorder. By using Fourier Transform Infrared Spectroscopy (FT-IR) and Circular Dichroism (CD) it has been found that CHAs affect the conformation of the adsorbed proteins. FT-IR spectroscopy shows that protein adhesion on CHA surface results in a significant reduction in helicity for both proteins on both substrates, as function of the coating extent as well as modification in the beta-structures. CD spectroscopy of the HSA and BSA released in solution after desorption from the matrices shows that, while both proteins partially regain their helical structure, they show a distinct behaviour in their tertiary structure.

Two kinds of hydroxyapatite (HA) crystals were studied as subcutaneous fillers in order to evaluate how their different degree of crystallinity and dimensions influence in vivo resorption. By appropriately adjusting the synthesis temperature, poorly crystalline HA (HApc) and highly crystalline HA (HAhc) were synthesized into clusters of needle-shaped crystals of about 50 nm and plate-shaped crystals of about 100 nm, respectively. The clusters of HApc had larger dimensions (30 μm) than those of HAhc (3 μm). Subcutaneous in vivo inoculations were performed in ten 6-month-old FVB female mice. HAhc underwent complete macroscopic resorption already 4 weeks after the implantation while HApc still showed agglomerates at the eighth week. This unexpected finding may be ascribed to the different size and morphology of the HAhc nanocrystals responsible for a lower aggregation and microcluster dimension than HApc nanocrystals.

New biomimetic carbonate-hydroxyapatite nanocrystals (CHA) have been designed and synthesized in order to obtain a remineralization of the altered enamel surfaces. Synthesized CHA mimic for composition, structure, nano dimension and morphology bone apatite crystals and their chemical-physical properties resemble closely those exhibited by enamel natural apatite. CHA can chemically bound themselves on the surface of natural enamel apatite thanks to their tailored biomimetic characteristics. The remineralization effect induced by CHA represents a real new deposition of carbonate-hydroxyapatite into the eroded enamel surface scratches forming a persistent biomimetic mineral coating, which covers and safeguards the enamel structure. The experimental results point out the possibility to use materials alternative to fluoride compounds which is commonly utilized to contrast the mechanical abrasions and acid attacks. The apatitic synthetic coating is less crystalline than enamel natural apatite, but consists of a new biomimetic apatitic mineral deposition which progressively fills the surface scratches. Therefore the application of biomimetic CHA may be considered an innovative approach to contrast the acid and bacteria attacks.

Samples of poly2-hydroxyethylmethacrylate (PHEMA) hydrogel were submitted to the biomimetic method, recently proposed by Japanese researchers. By this way it was possible to obtain an hydroxyapatite coating. The experimental results suggest that, as reported in the literature for other supports, the silicate ions released from the glass in the first stage bind themselves to the polymeric support. The adhesive strength was measured and turned out to be higher than the one reported for PMMA substrate. The biomimetic treatment has a strong effect on the outstanding property of the hydrogel, the swelling ratio that is increased from Deltam/m degrees= 0.56 to Deltam/m degrees= 1.03. Biomimetic method promoted cells adhesion on PHEMA substrate.

Purpose Natural resources are receiving growing interest because of their possible conversion from a cheap and easily available material into a biomedical product. Cuttlefish bone from Sepia Officinalis was investigated in order to obtain an hydroxyapatite porous scaffold using hydrothermal transformation. Methods Complete conversion of the previous calcium carbonate (aragonite) phase into a calcium phosphate (hydroxyapatite) phase was performed with an hydrothermal transformation at 200 °C (∼15 atm), for four hours, with an aqueous solution of KH2PO4 in order to set the molar ratio Ca/P = 10/6 in a reactor (Parr 4382). The complete conversion was then analyzed by TGA, ATR-FTIR, x-ray diffraction, and SEM. Moreover, the material was biologically investigated with MC3T3-E1 in static cultures, using both osteogenic and maintenance media. The expression of osteogenic markers as ALP and osteocalcin and the cell proliferation were investigated. Results Cuttlefish bone has been successfully transformed from calcium carbonate into calcium phosphate. Biological characterization revealed that osteogenic markers are expressed using both osteogenic and maintenance conditions. Cell proliferation is influenced by the static culture condition used for this three-dimensional scaffold. Conclusions The new scaffold composed by hydroxyapatite and derived for a natural source presents good biocompatibility and can be used for further investigations using dynamic cultures in order to improve cell proliferation and differentiation for bone tissue engineering.

A new method for altered enamel surface remineralization has been proposed. To this aim carbonate-hydroxyapatite nanocrystals which mimic for composition, structure, nanodimensions, and morphology dentine apatite crystals and resemble closely natural apatite chemical-physical properties have been used. The results underline the differences induced by the use of fluoride ions and hydroxyapatite nanocrystals in contrasting the mechanical abrasions and acid attacks to which tooth enamel is exposed. Fluoride ions generate a surface modification of the natural enamel apatite crystals increasing their crystallinity degree and relative mechanical and acid resistance. On the other hand, the remineralization produced by carbonate-hydroxyapatite consists in a deposition of a new apatitic mineral into the eroded enamel surface scratches. A new biomimetic mineral coating, which progressively fills and shadows surface scratches, covers and safeguards the enamel structure by contrasting the acid and bacteria attacks.

The osteointegration rate of titanium (Ti; TI01) and duplex Ti plus HA (HT01) coating systems with high surface roughness was investigated in healthy, aged, and oestrogen-deficient sheep. After having evaluated the bone quality, TI01 and HT01 rods were implanted in the tibial diaphyses (two implants for each tibia) and epiphyses (1 implant for each tibia) of five young (YOUNG), five aged (AGED), and five aged and ovariectomized (OVX) sheep. The iliac crest trabecular bone volume (BV/TV) and number (Tb.N) in OVX sheep were respectively 33.5% and 28.5% lower than in YOUNG sheep (p < 0.005) and lower than in the AGED group (BV/TV, -17%; Tb.N, -13.5%; not significant); in the OVX group the trabecular separation was 77.9% higher than in YOUNG (p < 0.05) and 30.9% higher than in AGED animals. Lumbar vertebrae L5 bone mineral density was significantly lower in AGED (8.9%, p < 0.05) and OVX sheep (19.3%, p < 0.0005) when compared with YOUNG animals. Five samples of five sheep from each group were analyzed for each observation. At 3 months, in cortical bone both affinity index and pushout test results showed no significant differences between the two materials in each group of animals. In trabecular bone, the affinity index of HT01 was significantly higher than that of TI01 in each group of animals (YOUNG, 90.7%; AGED, 76.9%; OVX, 49.9%) with no significant differences between groups. In conclusion, the performance of TI01 and HT01 surfaces was high not only in YOUNG, but also in OVX animals and, therefore, they might be useful for aged and osteoporotic patients.