Antibacterial effects of dentifrices against Streptococcus mutans in children: a comparative in vitro study.

Fluoridated dentifrices have antibacterial effects on children's teeth. On the other hand, the side effects encountered with the use of them have led researchers to look for safe alternatives. This study aimed to determine the antibacterial effect of different commercially available fluoride-free dentifrices on Streptococcus mutans (S. mutans) in comparison with different concentrations of fluoridated dentifrices. Study groups comprised of fluoride-free dentifrices, which contain Probiotic (Activated Charcoal Probiotic Dentifrice-Group P), Aloe Vera-Group AV and Salivary Proteins-Group SP. Fluoridated dentifrices containing 1450 ppm fluoride-Control Group 1 and 500 ppm fluoride-Control Group 2 served as control groups. Antibacterial activity was assessed by Minimum Inhibitory Concentrations and agar well diffusion assays on S. mutans. Biofilm inhibition assay was performed with dentifrices, which had antibacterial activities, and a negative control phosphate-buffered saline (Group PBS) on sterile hydroxyapatite discs against S. mutans. Statistical evaluation was performed. Only group AV showed an antibacterial effect on S. mutans, while control groups showed a similar antibacterial effect. The mean number of viable bacteria present in S. mutans biofilm in Control Group 1 and 2 and Group AV were statistically significantly lower than that in Group PBS, but there were no statistically significant differences between Control Groups and Group AV. Antibacterial activity of commercial dentifrices against S. mutans may be exerted by antibacterial components other than fluoride. Aloe vera-containing toothpaste showed an antibacterial effect on S. mutans, although not as much as the fluoride-containing toothpastes in the control groups. However, further in vivo and long-term studies are required.

Evaluation of the usefulness and quality of YouTube™ videos about children's electric toothbrushes.

OBJECTIVES: The effectiveness of mechanical tooth cleaning, which plays a crucial role in biofilm control, depends on the type of brush and technique. Parents can refer to websites such as YouTube™ for guidance on the selection and use of electric toothbrushes. The objective of this study was to examine the usefulness, quality and accuracy of the information on YouTube™ videos about electric toothbrushes for children. MATERIALS AND METHODS: A search was performed on YouTube™ for English language videos using the terms 'electric toothbrush for kids' and 'kids' electric toothbrush'. From the first 100 results, 64 videos were selected for further analysis. The videos were analysed for views, likes/dislikes, number of comments, upload source, duration and time since video upload. The usefulness and the quality of the selected videos were also measured. RESULTS: The majority of the videos mentioned toothbrush design (71.9%, n = 46) and toothbrush heads (62.5%, n = 40). The videos were generally determined to be moderately useful (46.9%), whereas very useful videos were found less frequently (12.5%). Slightly useful videos were mostly uploaded by laypeople. Very useful videos had significantly higher video durations than moderately and slightly useful videos (p = 0.029 and p = 0.002, respectively). CONCLUSIONS: YouTube™ can be an important source of information for parents to learn about electric toothbrushes for their children. However, watching videos based on upload source and length of time may provide more accurate information on this topic. Also, dental healthcare professionals could be included more often to improve the usefulness and quality of the videos.

The Effect of Two Different Light-Curing Units and Curing Times on Bulk-Fill Restorative Materials.

This study aimed to evaluate the effect of two different light-curing units and curing times on the surface microhardness (SMH), compressive strength (CS), and volumetric shrinkage (VS) of four restorative materials (FiltekTM Z250, FiltekTM Bulk Fill Posterior, Beautifil® Bulk Restorative, ACTIVATM BioACTIVE). For all tests, each material was divided into two groups depending on the curing unit (Woodpecker LED-E and CarboLED), and each curing unit group was further divided into two subgroups according to curing time (10 s and 20 s). SMH was evaluated using a Vickers hardness tester, CS was tested using a universal testing machine, and VS was measured using video imaging. In all the restorative materials cured with Woodpecker LED-E, the 20 s subgroup demonstrated significantly higher SMH values than the 10 s subgroup. In both light-curing time subgroups, the CarboLED group showed significantly higher CS values than the Woodpecker LED-E group for all restorative materials except FiltekTM Bulk Fill Posterior cured for 20 s. ACTIVATM BioACTIVE showed significantly greater volumetric change than the other restorative materials. A higher curing light intensity and longer curing time had a positive effect on the SMH and CS of the restorative materials tested in this study. On the other hand, curing unit and time did not show a significant effect on the VS values of restorative materials.

Antibacterial effects of saliva substitutes containing lysozyme or lactoferrin against Streptococcus mutans.

OBJECTIVE: To determine the antibacterial effects of different saliva-substitutes-containing-lysozyme(LYZ) or-lactoferrin(LF) on Streptococcus mutans(S. mutans) in comparison with human saliva. DESIGN: In vitro wound-healing assay was performed with L929 mouse fibroblast cell line by using various concentrations of LYZ and LF to determine optimum concentrations and to confirm do not show any cytotoxicity of proteins according to cell culture studies. Antibacterial effect was assessed by determining Minimum Inhibitory Concentrations for all groups on S.mutans. Bacterial adhesion of S. mutans for 4 h on hydroxyapatite(HAP) discs after application of different saliva substitutes was evaluated. The formulations were:saliva-substitute(Group SS);saliva-substitute-containing-Lactoferrin(Group SSLF);saliva-substitute-containing-Lysozyme(Group SSLYZ). Human saliva was control group(Group HS). RESULTS: In vitro wound healing assay results showed that, when added into the cell culture media, LYZ and LF significantly increase 48 -h scratch wound closure compared to the cell culture media(p < 0.0001). At the end of second day, samples treated with both between 2.5-100 µg/mL LF and 5-200 µg/mL LYZ were found to have significant wound healing effect(p < 001). It was observed that saliva-substitutes-containing-LYZ or-LF had antibacterial effects on S.mutans. Bacterial adhesion on HAP discs was observed significantly higher in control group than in study groups. The amount of adhered S. mutans was significantly higher in Group SS than other study groups(p < 0.0001). However, no statistically significant difference was found between the number of bacteria adhered to HAP discs between SSLYZ and SSLF groups(p > 0.05). CONCLUSIONS: The study of cell viability and wound healing was great significance in the optimum concentrations of LYZ and LF. Among formulations, saliva-substitutes-containing-LYZ or-LF exhibited higher inhibitory effect on S.mutans.

Effect of pediatric multivitamin syrups and effervescent tablets on the surface microhardness and roughness of restorative materials: An in vitro study.

BACKGROUND/PURPOSE: Multivitamin syrups and effervescent tablets are commonly used for dietary support in children; however, these preparations may have detrimental effects on the surface of restorative materials. The aim of this study was to evaluate the effect of two multivitamin syrups and two effervescent tablets taken daily on the surface microhardness and roughness of two different restorative materials. MATERIALS AND METHODS: The study groups were comprised of a conventional glass ionomer cement, Ketac Molar, and a giomer, Beautifil II. A total of 140 disc-shaped specimens were prepared and randomly assigned to 5 subgroups. The samples were immersed in 4 multivitamins (Supradyne syrup, Supradyne effervescent, Sambucol syrup, Sambucol effervescent) and deionized water (control group) for 2 min once a day for 28 days. Surface microhardness and roughness measurements were recorded at baseline and on the 7th, 14th, 21st and 28th days. Surface microhardness was measured using a Vickers hardness tester and surface roughness was determined using a profilometer. RESULTS: For all subgroups; the surface microhardness values of the Ketac Molar and Beautifil II demonstrated a statistically significant decrease from the baseline to the 28th day measurements (p < 0.05), while the surface roughness displayed increased values that were found to be statistically significant (p < 0.05). The Ketac Molar surface roughness values were significantly higher than Beautifil II in all subgroups for all measurement days (p = 0.0001). CONCLUSION: The prolonged use of multivitamin syrups and effervescent tablets may have negative effects on the physical properties of restorative materials.

Assessment of shear bond strength and microleakage of fissure sealant following enamel deproteinization: An in vitro study.

BACKGROUND: To evaluate the effect of two different deproteinizing agents (5.25% sodium hypochlorite and Papacarie®) prior to acid etching on the shear bond strength and microleakage of a fissure sealant material. MATERIAL AND METHODS: A total of 123 extracted noncarious human third molar teeth were randomly divided into three groups for each test: acid etching alone (control) (C), sodium hypochlorite (NaOCl), and Papacarie Duo® (PC). The shear bond strength tests were performed using a universal testing machine, and microleakage was evaluated using a dye penetration method. RESULTS: The mean shear bond strength values obtained in Group C were significantly lower than those of Group NaOCl and Group PC (p=0.0001). There were no significant differences between Group NaOCl and Group PC (p>0.05). No statistically significant difference was observed among the groups in terms of microleakage (p>0.05). CONCLUSIONS: Papacarie Duo® and 5.25% sodium hypochlorite treatments before etching increased the shear bond strength of the fissure sealant. However, pre-treatment with these agents did not decrease the microleakage between teeth and sealant. Key words:Deproteinization, microleakage, papain, dental seal, shear bond strength.

Effect of two different polishing systems on fluoride release, surface roughness and bacterial adhesion of newly developed restorative materials.

OBJECTIVES: To evaluate the effects of two different polishing systems on fluoride release, surface roughness and bacterial adhesion of five restorative materials MATERIALS AND METHODS: The study groups were comprised of five different restorative materials, Beautifil II (B); GCP Glass Fill (G); Amalgomer CR (A); Dyract XP (D); Fuji IX GP (F) and 21 specimens were prepared from each material. Each group was divided into three subgroups according to the polishing system: Mylar (control) (C), Sof-lex (S), and Enhance-Pogo (EP). The amount of fluoride release was measured using a fluoride ion-selective electrode and surface roughness was investigated with a profilometer. Bacterial adhesion on the materials was evaluated by optical density readouts for S.mutans on a spectrophotometer. RESULTS: The highest amount of fluoride was released from specimens in the S subgroup of group G during all measurement days. Surface roughness values were significantly lower in subgroup C than the other polishing systems in all study groups except group G (P < .05). Group A displayed significantly higher surface roughness values than the other material groups in both subgroups (S and EP) (P < .01). Highest bacterial adhesion was observed in the EP subgroup of group A. CONCLUSIONS: Polishing promoted a significant increase of fluoride release on restorative materials especially in glass ionomer-based materials. CLINICAL SIGNIFICANCE: This article stated that polishing promoted a significant increase of fluoride release on restorative materials especially in glass ionomer-based materials. Further, proper polishing systems must be chosen according to the structure and composition of materials to provide the best clinical benefits in terms of fluoride release, surface roughness and bacterial adhesion.

Short-term effect of ice-cream containing Bifidobacterium lactis Bb-12 on the number of salivary mutans streptococci and lactobacilli.

OBJECTIVE: Probiotic bacteria are thought to reduce the risk of some infectious diseases. The aim of the present study was to examine whether or not short-term consumption of ice-cream containing bifidobacteria can affect the salivary levels of mutans streptococci and lactobacilli in young adults. MATERIAL AND METHODS: A double-blind, randomized crossover study was performed and 24 healthy subjects (mean age 20 years) were followed over 4 periods. During periods 2 and 4 (10 days each), they ingested 100 ml (53 g) ice-cream containing Bifidobacterium lactis Bb-12 once daily or a control ice-cream without viable bacteria. Periods 1 and 3 were run-in and washout periods, respectively. Salivary mutans streptococci and lactobacilli were enumerated with chair-side kits at baseline and immediately after the intervention period. RESULTS: A statistically significant reduction (p<0.05) of salivary mutans streptococci was recorded after consumption of the probiotic ice-cream. A decline of high mutans streptococci counts was also seen after intake of the control ice-cream, but the difference compared to baseline was not statistically significant. The salivary lactobacilli levels were unaltered after both regimes. CONCLUSIONS: Daily consumtion of ice-cream containing probiotic bifidobacteria may reduce the salivary levels of mutans streptococci in young adults.