AIM:To determine whether the favorable effects of xylitol chewing gum/candy on oral health observed in healthy children and adults can be demonstrated in older people or individuals with disabilities? METHODS:Electronic and hand searches were performed to find prospective randomized or controlled clinical studies comparing effects of xylitol gum/candy with a polyol/no product control on oral health. 1171 studies were screened after duplicate removal. After applying inclusion and exclusion criteria, four studies in older and five studies in people with disabilities were reviewed. RESULTS:Clinically significant decreases in plaque accumulation were reported for xylitol gum/candy use in both populations. The results on gingival inflammation and caries occurrence were in line with these results. Use of high-concentration xylitol candy decreased counts of mutans streptococci in individuals with disabilities. The studies in frail, older people suggested that xylitol gum chewing may reduce dry mouth symptoms, increase salivation and improve self-perceived oral health. CONCLUSION:The effects of xylitol chewing gum/candy on oral health in older people or individuals with disabilities may be comparable to those reported for healthy individuals. These findings suggest that xylitol gum/candy may be a useful adjunct for oral health maintenance in both older people and people with disabilities.

A systematic review of published data was carried out to assess specific effects of xylitol chewing gum on levels of mutans streptococci (MS), dental plaque, or caries. Electronic and hand searches were performed to find clinical studies on levels of MS, or plaque, or caries comparing effects of xylitol gum with a polyol control gum. Prospective randomized or controlled clinical studies published before 2025 were included in the review. The search identified 908 titles on MS, 879 titles on plaque, and 658 on caries to be evaluated. After applying inclusion and exclusion criteria, 16 articles on MS, ten on plaque and five on caries were reviewed. In 12/14 studies xylitol gum significantly decreased MS counts compared with sorbitol gum. Plaque accumulation decreased in 6/10 studies and caries occurrence in 3/5 trials when xylitol gum was compared with sorbitol/sorbitol-containing gum. Three studies on MS and/or plaque accumulation had a maltitol gum control, but the results of the studies were conflicting. The best evidence of specific beneficial effects for xylitol gum differing from those of sorbitol gum are found in the evaluated MS and plaque studies. The results of the reviewed caries trials are in line with this idea. Xylitol gum chewing is suggested to act as an adjunct to toothbrushing for reducing caries-associated MS and plaque accumulation to control and prevent caries occurrence in children and adults. Adults with other plaque-related diseases like periodontal disease should also benefit from xylitol gum.

Journal Article Oral health benefits and safety of xylitol and potential cardiovascular risk: questioning the validity of the model of Witkowski et al. Get access Gregory C Valentine, Gregory C Valentine Department of Pediatrics, Division of Neonatology at University of Washington, 1959 NE Pacific St. Box 356320, RR542 HSB, Seattle, WA 98195-6320, USADepartment of Obstetrics & Gynecology, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX 77401, USADepartment of Oral Health Sciences at University of Washington, 1959 NE Pacific St, Seattle, WA 98195, USA Corresponding author. Email: [email protected] https://orcid.org/0000-0002-3055-2987 Search for other works by this author on: Oxford Academic PubMed Google Scholar Eva Söderling, Eva Söderling Institute of Dentistry, University of Turku, Turku, Finland Search for other works by this author on: Oxford Academic PubMed Google Scholar Peter Milgrom Peter Milgrom Department of Oral Health Sciences at University of Washington, 1959 NE Pacific St, Seattle, WA 98195, USA Search for other works by this author on: Oxford Academic PubMed Google Scholar European Heart Journal, ehaf058, https://doi.org/10.1093/eurheartj/ehaf058 Published: 11 March 2025

Purpose A systematic review of published data was carried out to assess the caries-preventive effects of xylitol chewing gums and candies in children. Methods Electronic and hand searches were performed to find clinical studies on the effects of xylitol chewing gums and candies on dental caries in children (≤ 18 years). Prospective randomised or controlled clinical trials published before 2023 were included in the review. Results The initial search identified 365 titles to be evaluated. After applying inclusion and exclusion criteria, 15 articles with either fair or low quality were reviewed. Nine articles studied chewing gums, five candies, and one both of them. In the ten evaluated xylitol chewing gum studies xylitol consumption significantly reduced caries occurrence when compared with no treatment or a placebo polyol gum. The effect was clinically significant in studies with high or moderate caries level at study baseline. The results also suggested that the caries-reducing effect of xylitol gums may differ from sorbitol/polyol gums. In five of the six heterogenous xylitol candy studies, no caries-reducing effect was found independent of caries level. In addition to caries level, also the daily xylitol dose was a confounding factor. Conclusion The present findings suggest that the caries-reducing effect of adding xylitol chewing gum to the daily diet has been well demonstrated in children and adolescents with high or moderate caries level at study baseline. Xylitol gum use could benefit subjects with active incipient caries lesions on smooth tooth surfaces.

Background Acidogenicity and production of an extracellular matrix (ECM) are important virulence factors for the dental caries-associated bacteria, such as Streptococcus mutans, that live in biofilms on tooth surface. The ECM protects the bacteria from the flushing and buffering effects of saliva resulting in highly acidic microenvironments inside the biofilm. Materials and methods In this in vitro study, we applied real-time assays to follow biofilm formation and pH decrease in a growth medium and saliva by three S. mutans strains, as well as acid neutralization inside the mature biofilm. Results were compared with the biofilm composition. Effects of a non-fermentable polyol, xylitol, on acid production and acid neutralization in mature biofilms were evaluated by real-time pH measurements and confocal microscopy. Results Combination of real-time pH measurements with biofilm accumulation assays revealed growth media dependent differences in the pH decrease and biofilm accumulation, as well as strain differences in acid production and biofilm formation but not in the buffer diffusion through ECM. The presence of xylitol reduced the pH drop during biofilm formation of all strains. In addition, with strain Ingbritt xylitol reduced the amount of ECM in biofilm, which increased the rate of acid neutralization inside the biofilm after buffer exposure. Conclusion Our results stress the importance of biofilm matrix in creating the acidic environment inside a S. mutans biofilm, especially in the presence of saliva. In addition, our results suggest a novel mechanism of xylitol action. The observed increase in the permeability of the S. mutans ECM after xylitol exposure may allow acid-neutralizing saliva to reach deeper layer of the biofilms and thus, in part, explain previous clinical observations of reduced plaque acidogenicity after frequent xylitol use.

Postbiotics offer better properties than probiotics. This study investigated the antimicrobial activity of Lactiplantibacillus plantarum EIR/IF-1 postbiotics against pH-adaptive bacteria, namely Prevotella denticola, Fusobacterium nucleatum, and Streptococcus sanguinis. Cell-free culture media of L. plantarum EIR/IF-1 were used as postbiotics in either crude (acidic) or neutralized form to also understand non-pH-dependent antimicrobial potential. Minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and viable cell counts were determined for crude and neutralized postbiotics. Culture media adjusted to different pH values were also compared to adjusted media with postbiotics to understand the strength of organic acids in postbiotics. Antibiofilm activity of postbiotics was determined against polymicrobial biofilm formation. Finally, the toxicity of crude postbiotics was tested on human periodontal ligament fibroblast cells (hPDLFCs). MIC values of crude postbiotics were 12.5 mg/mL for all strains. F. nucleatum and P. denticola strains were sensitive to neutralized postbiotics after 48 h of incubation. Moreover, 12.5 and 25 mg/mL postbiotics inhibited biofilm formation and 2.5 mg/mL and lower concentrations of crude postbiotics showed no cytotoxicity in hPDLFCs. This study showed that postbiotics have antimicrobial activity against pH-adaptive oral bacteria and no cytotoxic effect on hPDLFCs depending on the dose. The non-acidic antimicrobial components of postbiotics could also enable their safe use in the oral cavity.

A systematic review of published data was conducted with the aim of assessing the effects of sugar-free polyol chewing gums on gingival inflammation. Electronic and hand searches were performed to find clinical studies concerning the effects of sugar-free chewing gums on gingival scores. Prospective randomized controlled clinical trials published between 1971 and 2021 were included in the review. The initial search identified 46 erythritol, 102 xylitol, 23 sorbitol, and nine maltitol chewing gum articles. After applying inclusion and exclusion criteria, seven xylitol chewing gum studies, one sorbitol, and one maltitol chewing gum study with either high or fair quality were reviewed. In five out of the seven xylitol studies, xylitol gum decreased gingival scores. In two studies, xylitol decreased gingival scores compared to a polyol gum, and in three studies compared to no gum/gum base. As for sorbitol and maltitol, only sorbitol gum chewing showed a small decrease in gingival scores compared to the controls. Habitual xylitol gum chewing may reduce gingival inflammation. The low number of studies and their heterogeneity provide clear indications that the effects of sugar-free polyol chewing gums on gingival inflammation need further, well-controlled studies. Sugar-free chewing gums, especially xylitol gum, may function as adjuncts to toothbrushing for reducing gingival inflammation, but the evidence so far is inconclusive.

Previous studies have indicated that the exopolysaccharides of lactic acid bacteria exhibit antibiofilm activity against non-oral bacteria by preventing their initial adhesion to surfaces and by downregulating the expression of genes responsible for their biofilm formation. The aims of this study were to (1) characterize the exopolysaccharides (EPSs) of Lactobacillus plantarum EIR/IF-1 postbiotics, (2) test their antibiofilm effect on dual biofilms, and (3) evaluate their bacterial auto-aggregation, co-aggregation, and hydrocarbon-binding inhibitory activity. The EPSs were characterized by FTIR, HPLC, and thermogravimetric analysis. Bacterial auto- and co-aggregation were tested by Kolenbrander's method and hydrocarbon binding was tested by Rosenberg's method. Dual biofilms were formed by culturing Fusobacterium nucleatum ATCC 25586 with one of the following bacteria: Prevotella denticola ATCC 33185, P. denticola AHN 33266, Porphyromonas gingivalis ATCC 33277, P. gingivalis AHN 24155, and Filifactor alocis ATCC 35896. The EPSs contained fractions with different molecular weights (51 and 841 kDa) and monosaccharides of glucose, galactose, and fructose. The EPSs showed antibiofilm activity in all the biofilm models tested. The EPSs may have inhibited bacterial aggregation and binding to hydrocarbons by reducing bacterial hydrophobicity. In conclusion, the EPSs of L. plantarum EIR/IF-1, which consists of two major fractions, exhibited antibiofilm activity against oral bacteria, which can be explained by the inhibitory effect of EPSs on the auto-aggregation and co-aggregation of bacteria and their binding to hydrocarbons.

Human milk oligosaccharides (HMOs), the third largest solid fraction in human milk, can modulate inflammation through Toll-like receptor signaling, but little is known about their immunomodulatory potential in the oral cavity. In this study, we determined whether the HMOs 2′-fucosyllactose (2′-FL) and 3-fucosyllactose (3-FL) regulate human-beta defensin (hBD)-2 and -3, cathelicidin (hCAP18/LL-37), and cytokine responses in human gingival cells using a three-dimensional oral mucosal culture model. The model was incubated with 0.1% or 1% 2′-FL and 3-FL, alone and in combination, for 5 or 24 h, and hBD-2, hBD-3, and hCAP18/LL-37 were analyzed by immunohistochemistry. The expression profiles of interleukin (IL)-1, IL-1RA, IL-8, and monocyte chemoattractant protein (MCP)-1 were determined by LUMINEX immunoassay. The combination of 1% 2′-FL and 1% 3-FL, and 1% 3-FL alone, for 24 h upregulated hBD-2 protein expression significantly (p < 0.001 and p = 0.016, respectively). No changes in the other antimicrobial peptides or proinflammatory cytokines were observed. Thus, 3-FL, alone and in combination with 2′-FL, stimulates oral mucosal secretion of hBD-2, without effecting a proinflammatory response when studied in an oral mucosal culture model.

Human milk oligosaccharides (HMOs), the third largest solid fraction in human milk, can modulate inflammation through Toll-like receptor signaling, but little is known about their immunomodulatory potential in the oral cavity. In this study, we determined whether the HMOs 2’fucosyllactose (2’-FL) and 3-fucosyllactose (3-FL) regulate human-beta defensin (hBD)-2 and -3, cathelicidin (hCAP18/LL-37), and cytokine responses in human gingival cells using a three-dimensional oral mucosal culture model. The model was incubated with 0.1% or 1% 2’-FL and 3-FL, alone and in combination, for 5 or 24 h, and hBD-2, hBD-3, and hCAP18/LL-37 were analyzed by immunohistochemistry. The expression profiles of interleukin (IL)-1, IL-1RA, IL-8, and monocyte chemoattractant protein (MCP)-1 were determined by LUMINEX immunoassay. The combination of 1% 2’FL and 1% 3-FL, and 1% 3-FL alone, for 24 h upregulated hBD-2 protein expression significantly (p < 0.001 and p = 0.016, respectively). No changes in the other antimicrobial peptides or proinflammatory cytokines were observed. Thus, 3-FL, alone and in combination with 2 ́-FL, stimulates oral mucosal secretion of hBD-2, without effecting a proinflammatory response when studied in an oral mucosal culture model.

OBJECTIVES:A systematic review of published data was conducted with the aim of assessing the effects of xylitol consumption on the amount of dental plaque. MATERIALS AND METHODS:Electronic and hand searches were performed to find clinical studies concerning the effects of xylitol chewing gum or candies on dental plaque. Prospective randomized controlled clinical trials published between 1971 and 2020 conducted in healthy subjects were included in the review. RESULTS:The initial search identified 424 xylitol articles. After applying inclusion and exclusion criteria, altogether 14 articles (16 studies) were reviewed. The review identified 12 of the total of 14 xylitol chewing gum studies as having fair or high quality. In 13 of the 14 chewing gum studies, xylitol gum decreased plaque accumulation. In six studies, xylitol gum chewing decreased plaque compared to sorbitol gum, and in three studies compared to gum base/no gum. In three fair-quality studies conducted with xylitol candies, plaque accumulation did not change. CONCLUSIONS:Habitual xylitol gum chewing appears to show plaque-reducing effects that differ from those of sorbitol gum. This suggests specific effects for xylitol on plaque accumulation. Xylitol candies appear not to decrease plaque. The heterogeneity of the studies warrants further research. Clinical relevance Habitual xylitol gum chewing is likely to decrease plaque.

The use of different stimulants of saliva secretion produces samples where the secretions from the major salivary glands occur in different proportions. The concentrations of most salivary constituents depend on the flow rate of saliva. Standardization of saliva collections is especially important, since saliva varies greatly both inter- and intraindividually. The presence of bacteria, epithelial cells, and leukocytes further complicates the analyses of whole saliva. The bacterial action can also be stopped by centrifugation of the saliva. Centrifugation removes both the cells and the turbidity, which can interfere with many analytical techniques. Most salivary electrolytes can be determined from stored samples. Electrolytes, which are labile or which participate in precipitate formation in saliva, have to be determined immediately after collection. Special collection conditions and equipment may be used to avoid these effects.

OBJECTIVE:A systematic review of published data was conducted with the aim of assessing effects of xylitol and erythritol consumption on levels of mutans streptococci (MS) and the oral microbiota.MATERIALS AND METHODS:Electronic and hand searches were performed to find clinical microbiological studies concerning the consumption of xylitol and erythritol chewing gum or candies, and published between 2000 and 2019. Prospective randomized controlled clinical trials conducted in healthy subjects were included in the review.RESULTS:The initial search identified 561 xylitol and 83 erythritol studies. After applying inclusion and exclusion criteria, 21 xylitol studies and one erythritol study were reviewed. The review identified nine xylitol studies with a fair or high quality, four conducted in children and five in adults, all demonstrating a decrease in MS levels in association with habitual consumption of xylitol. The three microbiota studies employing multispecies probe approaches revealed no effects for xylitol on the microbiota. The only erythritol study fulfilling the inclusion criteria showed no consistent effects on MS levels.CONCLUSIONS:Xylitol consumption is likely to decrease MS counts but it may not change the overall microbiota. Xylitol shows thus properties of an oral prebiotic. More studies are needed to demonstrate the effects of erythritol on MS.

BackgroundRegular consumption of xylitol decreases the number of cariogenic streptococci in dental plaque. In vitro biofilm models to study the mechanism of xylitol action have been set-up, but the obtained results are contradictory. Biofilm growth is a dynamic process with time-specific characteristics that may remain undetected in conventional end-point biofilm tests. In this study we used an impedance spectroscopy instrument, xCELLigence Real Time Cell Analyzer (RTCA), that allows label-free, non-invasive real-time monitoring of biofilm formation, to explore effects of xylitol on biofilm formation by Streptococcus mutans. Based on the obtained information of biofilm dynamics, we assessed the number of viable bacteria, the polysaccharide content, and the expression levels of selected genes involved in glucan-mediated biofilm formation in different biofilm stages. Xylitol inhibition was compared with that of erythritol; another polyol suggested to have a positive impact on oral health.ResultsOur results showed that real-time monitoring provided new information of polyol-induced changes in S. mutans biofilm formation dynamics. The inhibitory effect of polyols was more pronounced in the early stages of biofilm formation but affected also the measured total amount of formed biofilm. Effects seen in the real-time biofilm assay were only partially explained by changes in CFU values and polysaccharide amounts in the biofilms. Both xylitol and erythritol inhibited real-time biofilm formation by all the nine tested S. mutans strains. Sensitivity of the strains to inhibition varied: some were more sensitive to xylitol and some to erythritol. Xylitol also modified the expression levels of gbpB, gtfB, gtfC and gtfD genes that are important in polysaccharide-mediated adherence of S. mutans.ConclusionThe erythritol- and xylitol- induced inhibition of biofilm formation was only partly explained by decrease in the number of viable S. mutans cells or the amount of polysaccharides in the biofilm matrix, suggesting that in addition to reduced proliferation also the matrix composition and thereby the surface attachment quality of biofilm matrix may be altered by the polyols.

This in vitro study was designed to evaluate the effect of sol-gel derived TiO2 coating on blood coagulation, blood protein adsorption, and platelet response on zirconia surfaces. Square-shaped zirconia (n=96) (10x10x2 mm) was cut, ground, sintered, and finally cleansed ultrasonically in each of acetone and ethanol for 5 minutes. Three experimental groups (n=32) were fabricated: (a) zirconia coated with sol-gel derived TiO2, (b) zirconia coated with sol-gel derived TiO2 and treated with ultraviolet (UV) irradiation for 1 hour, and (c) non-coated zirconia as control. The coatings were prepared from tetraisopropyl orthotitanate solution by dip-coating. The thrombogenicity of the specimens was evaluated using a whole blood kinetic clotting time method where the extent of blood clotting was evaluated at 10, 20, 30, 40, 50, and 60 minutes (n=4/time point, total n=24/group). Scanning electron microscope images were taken to observe platelet morphologies after 1-hour incubation with platelet-rich plasma (PRP) (n=5/group). Surface characteristics were visualized using atomic force microscopy (n=1/group). Adsorption of plasma proteins and fibronectin on each surface was studied by gel electrophoresis (n=2/group). Significant differences were observed in blood coagulation between the test groups at 20-, 30-, 40-, and 50-minute time points (p<0.005). UV treated TiO2 coated specimens showed fastest blood coagulation followed by TiO2 coated and non-coated specimens. Furthermore, platelets appeared at a higher activation state on coated specimens. Gel electrophoresis revealed no difference in protein adsorption among the experimental groups. In summary, TiO2 coatings promoted blood coagulation, and it was further enhanced by UV treatment, which has the potential to hasten the wound healing process in vivo.

Streptococcus mutans is able to form a high-affinity biofilm on material surfaces. S mutans has also been detected around infected implants. Bioactive glasses (BAGs) have been shown to possess antibacterial effects against S mutans and other microorganisms. This in vitro study was performed to investigate the influence of BAG air abrasion on S mutans biofilm on sandblasted and acid-etched titanium surfaces. Sandblasted and acid-etched commercially pure titanium discs were used as substrates for bacteria (n = 107). The discs were immersed in an S mutans solution and incubated for 21 hours to form an S mutans biofilm. Twenty colonized discs were subjected to air abrasion with Bioglass 45S5 (45S5 BAG), experimental zinc oxide containing BAG (Zn4 BAG), and inert glass. After the abrasion, the discs were incubated for 5 hours in an anaerobic chamber followed by an assessment of viable S mutans cells. Surface morphology was evaluation using scanning electron microscopy (n = 12). The thrombogenicity of the glass particle-abraded discs (n = 75) was evaluated spectrophotometrically using whole-blood clotting measurement at predetermined time points. Air abrasion with 45S5 and Zn4 BAG eradicated S mutans biofilm. Significantly fewer viable S mutans cells were found on discs abraded with the 45S5 or Zn4 BAGs compared with the inert glass (P < .001). No significant differences were found in thrombogenicity since blood clotting was achieved for all substrates at 40 minutes. Air abrasion with BAG particles is effective in the eradication of S mutans biofilm from sandblasted and acid-etched titanium surfaces. Zn4 and 45S5 BAGs had similar biofilm-eradicating effects, but Zn4 BAG could be more tissue friendly. In addition, the steady release of zinc ions from Zn4 may enhance bone regeneration around the titanium implant and may thus have the potential to be used in the treatment of peri-implantitis. The use of either BAGs did not enhance the speed of blood coagulation.

PURPOSE:To explore early S. mutans biofilm formation on hydrothermally induced nanoporous TiO2 surfaces in vivo and to examine the effect of UV light activation on the biofilm development.MATERIALS AND METHODS:Ti-6Al-4V titanium alloy discs (n = 40) were divided into four groups with different surface treatments: noncoated titanium alloy (NC); UV treated noncoated titanium alloy (UVNC); hydrothermally induced TiO2 coating (HT); and UV treated titanium alloy with hydrothermally induced TiO2 coating (UVHT). In vivo plaque formation was studied in 10 healthy, nonsmoking adult volunteers. Titanium discs were randomly distributed among the maxillary first and second molars. UV treatment was administered for 60 min immediately before attaching the discs in subjects' molars. Plaque samples were collected 24h after the attachment of the specimens. Mutans streptococci (MS), non-mutans streptococci, and total facultative bacteria were cultured, and colonies were counted.RESULTS:The plaque samples of NC (NC + UVNC) surfaces showed over 2 times more often S. mutans when compared to TiO2 surfaces (HT + UVHT), with the number of colonized surfaces equal to 7 and 3, respectively.CONCLUSION:This in vivo study suggested that HT TiO2 surfaces, which we earlier showed to improve blood coagulation and encourage human gingival fibroblast attachment in vitro, do not enhance salivary microbial (mostly mutans streptococci) adhesion and initial biofilm formation when compared with noncoated titanium alloy. UV light treatment provided Ti-6Al-4V surfaces with antibacterial properties and showed a trend towards less biofilm formation when compared with non-UV treated titanium surfaces.

To determine the effect of a probiotic combination of Lactobacillus rhamnosus GG (LGG) and Bifidobacterium lactis BB-12 on the gingival health, dental plaque accumulation, and the oral carriage of four putative periodontal pathogens in healthy adolescents. 108 schoolboys, aged 13-15 years, participated in this study. They were divided into two groups: probiotics (n=54) and placebo (n=54). Both groups received two probiotic-laced or placebo lozenges twice a day during a four-week period. Plaque Index (PI) and Gingival Index (GI) were recorded at baseline and after four weeks. Salivary and plaque carriage of Aggregatibacter actinomycetemcomitans , Porphyromonas gingivalis , Prevotella intermedia , Fusobacterium nucleatum were also monitored likewise. 101 subjects completed the study. A statistically significant reduction in GI was seen in the probiotic group as compared to the placebo group ( P =0.012). A reduction in PI was found for both groups, with no difference observed between the groups after intervention ( P =0.819). Probiotic lozenges significantly reduced levels of A. actinomycetemcomitans and F. nucleatum in saliva and plaque ( P <0.05) and levels of P. gingivalis in plaque ( P <0.05), while no significant changes were found in the control group. A significant reduction ( P <0.001) was also noted in the total salivary bacterial counts of the test group. The short-term daily consumption of LGG and BB-12 probiotic lozenges improved the gingival health in adolescents and decreased the microbial counts of A. actinomycetemcomitans , and P. gingivalis . Hence probiotic supplements may serve as a simple adjunct to standard oral care for promoting the oral health in adolescents.

The purpose of this study was to evaluate blood and platelet response to nanostructured TiO2 coatings and to investigate the effect of Ultraviolet (UV) light treatment on blood clotting ability, platelet activation and protein adhesion. Ti-6Al-4V titanium alloy plates (n = 138) were divided into three groups; a sol–gel derived MetAliveTM coating (MA); hydrothermal coating (HT); and a non-coated group (NC). Sixty nine titanium substrates were further treated with UV light for 1 h. The thrombogenicity of the titanium substrates was assessed using fresh human blood with a whole blood kinetic clotting time method. The platelet adhesion test was conducted to evaluate the morphology and adhesion behavior of the platelets on the titanium substrates. Human diluted plasma and bovine fibronectin were used to evaluate protein adsorption. Total clotting time for the UV treated HT, MA and NC titanium substrates was almost 40 min compared to 60 min for non-UV substrates, the total clotting time for the UV treated groups were significantly lower than that of the non UV NC group (p < 0.05). UV light treatment had significantly enhanced coagulation rates. The HT and MA substrates presented more platelet aggregation, spreading and pseudopod formation in comparison with the NC substrates. UV treatment did not affect the platelet activation and protein adsorption. This in vitro study concluded that nanostructured titanium dioxide implant surfaces obtained by sol–gel and hydrothermal coating methods increased coagulation rates and enhanced platelet response when compared with non-coated surfaces. UV light treatment clearly improved thrombogenicity of all examined Ti-6Al-4V surfaces.

The purpose of this study was to evaluate effects of titanium surfaces air-abraded with particles of Bioglass (R) 45S5 and three-ZnO and SrO doped compositions on the viability, adhesion and biofilm formation of Streptococcus mutans. A statistically significant decrease in the viability of S. mutans was observed for all titanium discs air-particle abraded with the BAGs (p < 0.001). Also, a significant effect on diminishing biofilm formation on the titanium discs was seen for all BAGs (p < 0.01). No differences were noticed in S. mutans adhesion on titanium surfaces treated with different glasses (p = 0.964). Static SBF immersion experiments showed that after 2 and 48 h the BAG doped with 4 mol% ZnO demonstrated the highest Zn2+ ion concentration released into SBF (0.2 mg L-1). 45S5 BAG demonstrated the highest statistically significant increase in the pH throughout the 120 min of static immersion (p < 0.001). In conclusion, we showed that titanium alloy discs abraded with particles of the experimental compositions and 45S5 BAG had strong antimicrobial activity against S. mutans and they suppressed S. mutans biofilm formation. The antimicrobial activity of 45S5 BAG was attributed to high pH whereas for the Zn-containing BAGs antimicrobial activity was due to steady release of Zn2+ into the interfacial solution.