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Journal of Prosthodontic Research Jun 2024Titanium implants have revolutionized restorative and reconstructive therapy, yet achieving optimal osseointegration and ensuring long-term implant success remain...
Optimizing implant osseointegration, soft tissue responses, and bacterial inhibition: A comprehensive narrative review on the multifaceted approach of the UV photofunctionalization of titanium.
Titanium implants have revolutionized restorative and reconstructive therapy, yet achieving optimal osseointegration and ensuring long-term implant success remain persistent challenges. In this review, we explore a cutting-edge approach to enhancing implant properties: ultraviolet (UV) photofunctionalization. By harnessing UV energy, photofunctionalization rejuvenates aging implants, leveraging and often surpassing the intrinsic potential of titanium materials. The primary aim of this narrative review is to offer an updated perspective on the advancements made in the field, providing a comprehensive overview of recent findings and exploring the relationship between UV-induced physicochemical alterations and cellular responses. There is now compelling evidence of significant transformations in titanium surface chemistry induced by photofunctionalization, transitioning from hydrocarbon-rich to carbon pellicle-free surfaces, generating superhydrophilic surfaces, and modulating the electrostatic properties. These changes are closely associated with improved cellular attachment, spreading, proliferation, differentiation, and, ultimately, osseointegration. Additionally, we discuss clinical studies demonstrating the efficacy of UV photofunctionalization in accelerating and enhancing the osseointegration of dental implants. Furthermore, we delve into recent advancements, including the development of one-minute vacuum UV (VUV) photofunctionalization, which addresses the limitations of conventional UV methods as well as the newly discovered functions of photofunctionalization in modulating soft tissue and bacterial interfaces. By elucidating the intricate relationship between surface science and biology, this body of research lays the groundwork for innovative strategies aimed at enhancing the clinical performance of titanium implants, marking a new era in implantology.
PubMed: 38853001
DOI: 10.2186/jpr.JPR_D_24_00086 -
Journal of Dentistry May 2024Previous studies on short- and long-term pellicles showed that the enamel pellicle provides partial protection against erosion. The aim of the present study was to...
OBJECTIVES
Previous studies on short- and long-term pellicles showed that the enamel pellicle provides partial protection against erosion. The aim of the present study was to investigate the protective properties of clinically relevant pellicles formed within 2 to 24 h. The hypothesis was that factors such as pellicle formation time, intraoral location, and acidic challenge severity would not influence the erosion-protective properties of the pellicle.
METHODS
Six subjects participated in the study. Bovine enamel specimens were prepared and intraorally exposed at buccal or palatal sites for 2, 6, 12, and 24 h to allow pellicle formation, followed by erosion using 0.1 % or 1 % citric acid. Calcium release and surface microhardness were measured, and specimens were analysed using scanning and transmission electron microscopy. Quantitative data were statistically analysed with three-way ANOVA and Tuckey's multiple comparison test (p = 0.05).
RESULTS
Pellicle formation time and intraoral location did not significantly influence the erosion-protective properties of the pellicle, while citric acid concentration significantly affected enamel erosion. The pellicle thickness increased with longer formation times and on buccal sites, but decreased or was entirely removed following treatment with 0.1 % or 1 % citric acid, respectively. The enamel surface exhibited a characteristic erosion pattern.
CONCLUSIONS
This study underscores the importance of investigating pellicle properties within the critical 2- to 24-h timeframe and highlights the significance of pellicle thickness in acid resistance.
CLINICAL SIGNIFICANCE
These findings provide valuable insights into the factors influencing the protective properties of enamel pellicles and could guide preventive measures in dental practice.
PubMed: 38815730
DOI: 10.1016/j.jdent.2024.105103 -
Materials (Basel, Switzerland) Apr 2024Scanning force microscopy (SFM) is one of the most widely used techniques in biomaterials research. In addition to imaging the materials of interest, SFM enables the... (Review)
Review
Scanning force microscopy (SFM) is one of the most widely used techniques in biomaterials research. In addition to imaging the materials of interest, SFM enables the mapping of mechanical properties and biological responses with sub-nanometer resolution and piconewton sensitivity. This review aims to give an overview of using the scanning force microscope (SFM) for investigations on dental materials. In particular, SFM-derived methods such as force-distance curves (scanning force spectroscopy), lateral force spectroscopy, and applications of the FluidFM will be presented. In addition to the properties of dental materials, this paper reports the development of the pellicle by the interaction of biopolymers such as proteins and polysaccharides, as well as the interaction of bacteria with dental materials.
PubMed: 38730904
DOI: 10.3390/ma17092100 -
Journal of Dentistry Jul 2024This laboratory study assessed the performance of a novel fluoride dentifrice containing micro-fibrillated cellulose (MFC) and entrapped silica. (Comparative Study)
Comparative Study
OBJECTIVES
This laboratory study assessed the performance of a novel fluoride dentifrice containing micro-fibrillated cellulose (MFC) and entrapped silica.
METHODS
Removal of extrinsic stains was assessed using the pellicle cleaning ratio (PCR) method, and radioactive dentin abrasivity (RDA) was measured, to calculate a cleaning efficiency index (CEI). Fluoride efficacy was evaluated using widely used remineralization and fluoride uptake methods. The test product (Protegera™) was compared to common dentifrices (Crest - Cavity Protection™ and ProHealth™, Sensodyne Pronamel™, Arm & Hammer™ Advanced Whitening, Crest ProHealth™, and Colgate Optic White™).
RESULTS
The PCR for the MFC dentifrice (141) was comparable to three known marketed stain-removing dentifrices (Arm & Hammer™ Advanced Whitening, Crest ProHealth™, and Colgate Optic White™) but it had a significantly lower RDA (88 ± 6) than 5 other products. This gave it the highest CEI of the tested products (2.0). In a 10-day pH cycling study, the fluoride efficacy of the MFC product was comparable to Sensodyne Pronamel and Crest Cavity Protection. The MFC dentifrice was superior for promoting fluoride uptake into incipient enamel lesions compared to the USP reference dentifrice.
CONCLUSION
The MFC dentifrice has low abrasion, but despite this, it is highly effective in removing stained pellicle. It also is an efficacious fluoride source when compared to relevant commercially available fluoride dentifrices with high dentin abrasivity.
CLINICAL SIGNIFICANCE
The addition of micro-fibrillated cellulose to a fluoride dentifrice gives a low abrasive product that can effectively remove external stains, and serve as an effective fluoride source. This combination of benefits seems well suited to enamel protection and caries prevention.
Topics: Dentifrices; Tooth Discoloration; Cellulose; Humans; Tooth Abrasion; Dentin; Tooth Remineralization; Cariostatic Agents; Dental Pellicle; Fluorides; Silicon Dioxide; Materials Testing; Dental Enamel; Hydrogen-Ion Concentration; Phosphates; Toothpastes
PubMed: 38714242
DOI: 10.1016/j.jdent.2024.105038 -
Bioengineering (Basel, Switzerland) Apr 2024Cellulose nanocrystals (CNCs) are cellulose-derived nanomaterials that can be easily obtained, e.g., from vegetable waste produced by circular economies. They show...
Cellulose nanocrystals (CNCs) are cellulose-derived nanomaterials that can be easily obtained, e.g., from vegetable waste produced by circular economies. They show promising antimicrobial activity and an absence of side effects and toxicity. This study investigated the ability of CNCs to reduce microbial adherence and biofilm formation using in vitro microbiological models reproducing the oral environment. Microbial adherence by microbial strains of oral interest, and was evaluated on the surfaces of salivary pellicle-coated enamel disks in the presence of different aqueous solutions of CNCs. The anti-biofilm activity of the same CNC solutions was tested against and an oral microcosm model based on mixed plaque inoculum using a continuous-flow bioreactor. Results showed the excellent anti-adherent activity of the CNCs against the tested strains from the lowest concentration tested (0.032 wt. %, < 0.001). Such activity was significantly higher against than against ( < 0.01), suggesting a selective anti-adherent activity against pathogenic strains. At the same time, there was a minimal, albeit significant, anti-biofilm activity (0.5 and 4 wt. % CNC solution for and oral microcosm, respectively, = 0.01). This makes CNCs particularly interesting as anticaries agents, encouraging their use in the oral field.
PubMed: 38671777
DOI: 10.3390/bioengineering11040355 -
Regenerative Biomaterials 2024Eradicating biofouling from implant surfaces is essential in treating peri-implant infections, as it directly addresses the microbial source for infection and...
Eradicating biofouling from implant surfaces is essential in treating peri-implant infections, as it directly addresses the microbial source for infection and inflammation around dental implants. This controlled laboratory study examines the effectiveness of the four commercially available debridement solutions '(EDTA (Prefgel), NaOCl (Perisolv), HO (Sigma-Aldrich) and Chlorhexidine (GUM Paroex))' in removing the acquired pellicle, preventing pellicle re-formation and removing of a multi-species oral biofilm growing on a titanium implant surface, and compare the results with the effect of a novel formulation of a peroxide-activated 'Poloxamer gel (Nubone Clean)'. Evaluation of pellicle removal and re-formation was conducted using scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy to assess the surface morphology, elemental composition and chemical surface composition. Hydrophilicity was assessed through contact angle measurements. The multi-species biofilm model included , and , reflecting the natural oral microbiome's complexity. Biofilm biomass was quantified using safranin staining, biofilm viability was evaluated using confocal laser scanning microscopy, and SEM was used for morphological analyses of the biofilm. Results indicated that while no single agent completely eradicated the biofilm, the 'Poloxamer gel' activated with 'HO' exhibited promising results. It minimized re-contamination of the pellicle by significantly lowering the contact angle, indicating enhanced hydrophilicity. This combination also showed a notable reduction in carbon contaminants, suggesting the effective removal of organic residues from the titanium surface, in addition to effectively reducing viable bacterial counts. In conclusion, the 'Poloxamer gel + HO' combination emerged as a promising chemical decontamination strategy for peri-implant diseases. It underlines the importance of tailoring treatment methods to the unique microbial challenges in peri-implant diseases and the necessity of combining chemical decontaminating strategies with established mechanical cleaning procedures for optimal management of peri-implant diseases.
PubMed: 38435376
DOI: 10.1093/rb/rbae014 -
Archives of Oral Biology Apr 2024To study the effects of carbon dots (CDs), in combination with phytosphingosine (PHS), against acid-induced demineralization of hydroxyapatite in vitro.
OBJECTIVES
To study the effects of carbon dots (CDs), in combination with phytosphingosine (PHS), against acid-induced demineralization of hydroxyapatite in vitro.
METHODS
CDs were generated from citric acid and urea by microwave heating. Transmission electron microscope (TEM), FT-IR, and fluorescence intensity were used to characterize the CDs. A hydroxyapatite (HAp) model was used to investigate the protective effects of CDs, PHS, and their combinations with and without a salivary pellicle against acid-induced demineralization in vitro. Ca release as a parameter to evaluate the inhibition of demineralization was measured by capillary electrophoresis. The interactions between CDs, PHS, and HAp discs were investigated using a fluorescence detector.
RESULTS
Uniform-sized CDs were synthesized, showing typical optical characteristics. CDs exhibited no inhibition of acid-induced demineralization in vitro, in contrast to PHS. Notably, a pre-coating of CDs increased the protective effects of PHS against acid-induced demineralization, which was not disturbed by the presence of a salivary pellicle and Tween 20. Scanning electron microscope (SEM) confirmed the binding and layers formed of both CDs and PHS to the HAp surfaces. Based on fluorescence spectra CDs binding to HAp seemed to be dependent on Ca and PO interactions.
CONCLUSIONS
CDs combined with PHS showed protective effects against acid-induced demineralization of HAp discs in vitro.
Topics: Humans; Durapatite; Carbon; Spectroscopy, Fourier Transform Infrared; Tooth Demineralization; Sphingosine
PubMed: 38335699
DOI: 10.1016/j.archoralbio.2024.105911 -
Caries Research 2024Erosive tooth wear is a highly prevalent dental condition that is modified by the ever-present salivary pellicle. The aim of the present in situ study was to investigate...
INTRODUCTION
Erosive tooth wear is a highly prevalent dental condition that is modified by the ever-present salivary pellicle. The aim of the present in situ study was to investigate the effect of polyphenols on the ultrastructure of the pellicle formed on dentin in situ and a subsequent erosive challenge.
METHODS
The pellicle was formed on bovine dentin specimens for 3 min or 2 h in 3 subjects. After subjects rinsed with sterile water (negative control), 1% tannic acid, 1% hop extract, or tin/fluoride solution containing 800 ppm tin and 500 ppm fluoride (positive control), specimens were removed from the oral cavity. The erosive challenge was performed on half of the specimens with 1% citric acid, and all specimens were analyzed by transmission electron microscopy. Incorporation of tannic acid in the pellicle was investigated by fluorescence spectroscopy.
RESULTS
Compared to the negative control, ultrastructural analyses reveal a thicker and electron-denser pellicle after application of polyphenols, in which, according to spectroscopy, tannic acid is also incorporated. Application of citric acid resulted in demineralization of dentin, but to a lesser degree when the pellicle was pretreated with a tin/fluoride solution. The pellicle was more acid-resistant than the negative control when modified with polyphenols or tin/fluoride solution.
CONCLUSION
Polyphenols can have a substantial impact on the ultrastructure and acid resistance of the dentin pellicle, while the tin/fluoride solution showed explicit protection against erosive demineralization.
Topics: Humans; Animals; Cattle; Dental Enamel; Dental Pellicle; Fluorides; Tooth Erosion; Tin; Polyphenols; Tin Fluorides; Citric Acid; Dentin
PubMed: 38198764
DOI: 10.1159/000536199 -
Dentistry Journal Dec 2023In this study, we examined the cytotoxic effects of six commercial children's mouthrinses (designated as #1, #2, #3, #4, #5, and #6) and four commercial children's...
In this study, we examined the cytotoxic effects of six commercial children's mouthrinses (designated as #1, #2, #3, #4, #5, and #6) and four commercial children's toothpastes (designated as #1, #2, #3, and #4) on primary human neonatal melanocytes that were used as a representative model for oral melanocytes. Mouthrinses diluted directly with culture medium (1:2, 1:5, 1:10, 1:100, and 1:1000) were added to monolayers of melanocytes for 2 min, followed by 24 h recovery, after which MTS cytotoxicity assay was conducted. The extracts of each toothpaste were prepared (50% /), diluted in culture medium (1:2, 1:5, 1:10, 1:50, 1:100, and 1:1000), and added to cell monolayers for 2 min (standard brushing time), followed by an analysis of cell viability after 24 h. Results showed that all mouthrinses except mouthrinse #4 showed significantly greater loss of cell viability, ascribed to cetylpyridinium chloride (CPC) that induced significant cytotoxicity to melanocytes (IC = 54.33 µM). In the case of toothpastes, the examination of cellular morphology showed that a 2 min exposure to all toothpaste extracts induced a concentration-dependent decline in cell viability, pronounced in toothpaste containing sodium lauryl sulfate (SLS) detergent. Further results suggested SLS to be the critical driver of cytotoxicity (IC = 317.73 µM). It is noteworthy that toothpaste #1 exhibited much lower levels of cytotoxicity compared to the other three toothpastes containing SLS. Taken together, these findings suggest that the melanocytotoxicity of children's mouthrinse (#4) and toothpaste (#1) is comparatively low. To the best of our knowledge, this is the first study to examine the impact of children's toothpastes and mouthrinses on neonatal primary human melanocytes. Future studies to investigate these findings in a realistic scenario replicating oral cavity conditions of the presence of microbiota, pellicle layer and saliva, and other cell types are warranted.
PubMed: 38132425
DOI: 10.3390/dj11120287 -
Scientific Reports Nov 2023Dental hard tissues from different species are used in dental research, but little is known about their comparability. The aim of this study was to compare the erosive...
Dental hard tissues from different species are used in dental research, but little is known about their comparability. The aim of this study was to compare the erosive behaviour of dental hard tissues (enamel, dentin) obtained from human, bovine and equine teeth. In addition, the protective effect of the pellicle on each hard tissue under erosive conditions was determined. In situ pellicle formation was performed for 30 min on enamel and dentin samples from all species in four subjects. Calcium and phosphate release was assessed during 120 s of HCl incubation on both native and pellicle-covered enamel and dentin samples. SEM and TEM were used to examine surface changes in native enamel and dentin samples after acid incubation and the ultrastructure of the pellicle before and after erosive exposure. In general, bovine enamel and dentin showed the highest degree of erosion after acid exposure compared to human and equine samples. Erosion of human primary enamel tended to be higher than that of permanent teeth, whereas dentin showed the opposite behaviour. SEM showed that eroded equine dentin appeared more irregular than human or bovine dentin. TEM studies showed that primary enamel appeared to be most susceptible to erosion.
Topics: Humans; Animals; Cattle; Horses; Tooth Erosion; Dentin; Calcium; Hydrochloric Acid; Phosphates
PubMed: 37949920
DOI: 10.1038/s41598-023-46759-9