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International Journal of Oral Science Dec 2016Antibacterial dimethylaminododecyl methacrylate (DMADDM) was recently synthesized. The objectives of this study were to: (1) investigate antibacterial activity of...
Antibacterial dimethylaminododecyl methacrylate (DMADDM) was recently synthesized. The objectives of this study were to: (1) investigate antibacterial activity of DMADDM-containing primer on Streptococcus mutans impregnated into dentin blocks for the first time, and (2) compare the antibacterial efficacy of DMADDM with a previous quaternary ammonium dimethacrylate (QADM). Scotchbond Multi-Purpose (SBMP) bonding agent was used. DMADDM and QADM were mixed into SBMP primer. Six primers were tested: SBMP control primer P, P+2.5% DMADDM, P+5% DMADDM, P+7.5% DMADDM, P+10% DMADDM, and P+10% QADM. S. mutans were impregnated into human dentin blocks, and each primer was applied to dentin to test its ability to kill bacteria in dentinal tubules. Bacteria in dentin were collected via a sonication method, and the colony-forming units (CFU) and inhibition zones were measured. The bacterial inhibition zone of P+10% DMADDM was 10 times that of control primer (P<0.05). CFU in dentin with P+10% DMADDM was reduced by three orders of magnitude, compared with control. DMADDM had a much stronger antibacterial effect than QADM, and antibacterial efficacy increased with increasing DMADDM concentration. Dentin shear bond strengths were similar among all groups (P>0.1). In conclusion, antibacterial DMADDM-containing primer was validated to kill bacteria inside dentin blocks, possessing a much stronger antibacterial potency than the previous QADM. DMADDM-containing bonding agent was effective in eradicating bacteria in dentin, and its efficacy was directly proportional to DMADDM mass fraction. Therefore, DMADDM may be promising for use in bonding agents as well as in other restorative and preventive materials to inhibit bacteria.
Topics: Anti-Bacterial Agents; Biofilms; Dentin; Dentin-Bonding Agents; Humans; Materials Testing; Methacrylates; Quaternary Ammonium Compounds; Resin Cements; Streptococcus mutans
PubMed: 27811846
DOI: 10.1038/ijos.2016.43 -
Romanian Journal of Morphology and... 2015The purpose of this study was in vitro evaluation and comparison of the adhesion of self-etch (SE) adhesive systems applied on normal and sclerotic dentin. For this... (Comparative Study)
Comparative Study
The purpose of this study was in vitro evaluation and comparison of the adhesion of self-etch (SE) adhesive systems applied on normal and sclerotic dentin. For this study, Class 5 cavities were prepared on sound teeth as well as on teeth with sclerotic dentin. They were then restored by means of the SE 2-step OptiBond XTR (Kerr) and SE 1-step Bond Force (Tokuyama Dental) adhesive systems, as well as the Estelite Sigma Quick (Tokuyama Dental) composite resin. For teeth with sclerotic dentin, the hypermineralized superficial layer was removed by means of round bur on low speed, than the adhesive systems and composite resin were applied. These teeth were prepared for microscopic study according to the protocol specific to each microscope. SEM (scanning electron microscopy) examination reveals that on normal and sclerotic dentin, OptiBond XTR and Bond Force form hybrid layers with about the same thickness, greater in normal dentin, but only OptiBond XTR pervades into the dentinal tubules, both in normal and sclerotic dentin. However, TEM (transmission electron microscopy) examination of Bond Force reveals that it penetrates into the dentinal tubules as well, but only in the case of normal dentin. The thickness of the hybrid layers resulting from the application of the SE adhesive systems to sound dentin is different from the thickness of the hybrid layers obtained when the same adhesive systems have been applied to sclerotic dentin.
Topics: Dental Cements; Dentin; Humans; Sclerosis; Spectrometry, X-Ray Emission
PubMed: 26662138
DOI: No ID Found -
Dental Materials Journal Mar 2019We investigated the effects of the weekly application of pastes containing a surface reaction-type pre-reacted glass-ionomer (S-PRG) filler on dentin remineralization....
We investigated the effects of the weekly application of pastes containing a surface reaction-type pre-reacted glass-ionomer (S-PRG) filler on dentin remineralization. Human dentin blocks were demineralized and polished using pastes containing S-PRG filler (0, 5, and 30%), and then immersed in remineralizing solution for 1 month. Nanoindentation testing was carried out during the immersion period, and the dentin surfaces were examined using scanning electron microscopy. A nano-hydroxyapatite-containing paste was used for comparison. Immersion in demineralization solution had a marked negative effect on the mechanical properties in all specimens. The mechanical properties of specimens polished with S-PRG filler-containing pastes recovered significantly after immersion in remineralization solution for 1 month compared with the other specimens. After remineralization, the open dentinal tubules were filled with a remineralization layer in specimens polished with S-PRG filler-containing and nano-hydroxyapatite-containing pastes. S-PRG filler-containing pastes can aid dentin remineralization.
Topics: Dentin; Humans; Microscopy, Electron, Scanning; Tooth Demineralization; Tooth Remineralization
PubMed: 30541992
DOI: 10.4012/dmj.2018-015 -
International Dental Journal Jun 2024The objective of this in vitro study was to compare the effectiveness of a propolis-based herbal toothpaste with 5% sodium fluoride varnishin obstructing human dentinal... (Comparative Study)
Comparative Study
INTRODUCTION
The objective of this in vitro study was to compare the effectiveness of a propolis-based herbal toothpaste with 5% sodium fluoride varnishin obstructing human dentinal tubules; Scanning electron microscopy was utilised to obtain quantitative and qulitative data on tubular obstruction.
METHODS
Thirty-nine extracted human premolar teeth were collected. The cementum layer was removed using a water-cooled diamond bur and the smear layer using ethylenediaminetetraacetic acid (EDTA) 17%. Then, the samples were randomly divided into 3 groups (n = 13 each), as follows: group 1: dentin discs exposed to the propolis-based herbal toothpaste (Herbex); group 2: dentin discs exposed to 5% sodium fluoride varnish; and group 3: control. Then, all discs were observed and imaged in 4 non-overlapping fields by an electron microscope at 2000× magnification. The topography and number of open, closed, and semi-closed tubules were counted in all images. The data were analysed using Kruskal-Wallis test, Mann-Whitney U test, and Friedman test. The statistical analysis was performed with SPSS statistic 22.0 software, with a significance level of α = 0.05.
RESULTS
In pairwise comparisons of the groups considering the percentage of open, closed, and semi-closed tubules, the difference was not statistically significant between the 5% sodium fluoride varnish and propolis groups in the closed and semi-closed tubules, but it was statistically significant with the control group. Additionally, the percentage of open tubules in the propolis-based herbal toothpaste group was significantly lower than in the 5% sodium fluoride varnish and control group.
CONCLUSIONS
Both propolis-based herbal toothpaste and 5% sodium fluoride varnish is effective in blocking human dentin tubules to various extents.
Topics: Propolis; Humans; Toothpastes; Sodium Fluoride; Fluorides, Topical; Microscopy, Electron, Scanning; Dentin Sensitivity; In Vitro Techniques; Dentin; Dentin Desensitizing Agents; Bicuspid
PubMed: 38184459
DOI: 10.1016/j.identj.2023.11.014 -
Hua Xi Kou Qiang Yi Xue Za Zhi = Huaxi... Dec 2022The purpose of the study was to evaluate the effect of hydroxyapatite (HA)-based desensiti-zing agents and determine their influence on the bonding performance of mild... (Randomized Controlled Trial)
Randomized Controlled Trial
OBJECTIVES
The purpose of the study was to evaluate the effect of hydroxyapatite (HA)-based desensiti-zing agents and determine their influence on the bonding performance of mild universal adhesives.
METHODS
Mid-coronal dentin samples were sectioned from human third molars and prepared for a dentin-sensitive model. According to desensitizing applications, they were randomly divided into four groups for the following treatments: no desensitizing treatment (control), Biorepair toothpaste (HA-based desensitizing toothpaste) treatment, Dontodent toothpaste (HA-based desensitizing toothpaste) treatment, and HA paste treatment. Dentin tubular occlusion and occluded area ratios were evaluated by scanning electron microscopy (SEM). Furthermore, All-Bond Universal, Single Bond Universal, and Clearfil Universal Bond were applied to the desensitized dentin in self-etch mode. The wettability and surface free energy (SFE) of desensitized dentin were evaluated by contact angle measurements. Bonded specimens were sectioned into beams and tested for micro-tensile bond strength to analyze the effect of desensitizing treatment on the bond strength to dentin of universal adhesives.
RESULTS
SEM revealed that the dentin tubule was occluded by HA-based desensitizing agents, and the area ratios for the occluded dentin tubules were in the following order: HA group>Biorepair group>Dontodent group (<0.05). Contact angle analysis demonstrated that HA-based desensitizing agents had no statistically significant influence on the wettability of the universal adhesives (0.05). The SFE of dentin significantly increased after treatment by HA-based desensitizing agents (<0.05). The micro-tensile bond strength test showed that HA-based desensitizing toothpastes always decreased the μTBS values (<0.05), whereas the HA paste group presented similar bond strength to the control group (0.05), irrespective of universal adhesive types.
CONCLUSIONS
HA-based desensitizing agents can occlude the exposed dentinal tubules on sensitive dentin. When mild and ultra-mild universal adhesives were used for subsequent resin restoration, the bond strength was reduced by HA-based desensitizing toothpastes, whereas the pure HA paste had no adverse effect on bond strength.
Topics: Humans; Dental Cements; Dentin; Durapatite; Tensile Strength; Toothpastes
PubMed: 36416319
DOI: 10.7518/hxkq.2022.06.007 -
Journal of Dentistry Jul 2013This paper reviews a number of studies in oral biology and endodontics that deal with the reactivity of the pulpo-dentine complex in response to mechanical and... (Review)
Review
This paper reviews a number of studies in oral biology and endodontics that deal with the reactivity of the pulpo-dentine complex in response to mechanical and immunological stimuli. It can be hypothesized that these reactions could also apply to changes in dentine sensitivity following periodontal procedures. Some of these changes involve neurogenic inflammation of the pulp under exposed open tubules; this increases the rate of outward fluid flow through the tubules, making the overlying exposed dentine more sensitive. Other changes may be due to inflammation-related nerve sprouting of pulpal nerves, which can lead to innervation of more tubules than normal. Changes may also involve upregulation of new, more sensitive ion channels in the membranes of these nerves. The goal of the paper is to increase awareness of the complex issues involved in dentine sensitivity, so that future investigators may develop agents or techniques to stimulate mechanisms that mitigate dentine sensitivity, or to block mechanisms that aggravate the condition, for therapeutic effect.
Topics: Dental Pulp; Dentin; Dentin Permeability; Dentin Sensitivity; Dentinal Fluid; Humans; Inflammation Mediators; Ion Channels; Neurogenic Inflammation; Smear Layer
PubMed: 23929645
DOI: 10.1016/S0300-5712(13)70006-X -
Journal of Biomedical Optics Oct 2022The increase in root caries is a serious problem as society ages. Root caries is diagnosed by inspection and palpation, which are qualitative. A method to objectively...
SIGNIFICANCE
The increase in root caries is a serious problem as society ages. Root caries is diagnosed by inspection and palpation, which are qualitative. A method to objectively and quantitatively evaluate the progress of root caries in a clinical setting is strongly desired. The root caries could be diagnosed by measuring hardness because dentin becomes softer as the caries progresses. Vickers hardness has been customarily used as an indicator of tooth hardness. However, this method cannot be used to in vivo teeth because the teeth must be dried prior to measurement to make the indentation. A hardness meter using an indenter with light for tooth monitoring (HAMILTOM) is proposed as an optical device. HAMILTOM could measure hardness of teeth in wet condition as a dark area while applying a load to dentins without drying. Therefore, HAMILTOM may realize hardness measurements of in vivo teeth in a clinical setting quantitatively.
AIM
The aim of our study is to demonstrate the optical dentin hardness measuring device HAMILTOM using bovine dentin with different demineralization times and to evaluate the correlation between the dark areas measured by HAMILTOM and the Vickers hardness measured by the Vickers hardness tester.
APPROACH
The samples were 20 bovine dentins. They were demineralized by a lactic acid solution with different times and divided into groups 1 and 2 of 10 samples each. In both groups, the dark areas and Vickers hardness were measured for each sample. Group 1 was used to obtain a calibration curve to calculate Vickers hardness from the dark area. Group 2 was used to validate the calibration curve obtained from the dentin samples of group 1.
RESULTS
The areas appearing black without a total internal reflection of the indenter measured by HAMILTOM increased as the demineralization time increased. Additionally, the Vickers hardness of group 2 calculated by the dark areas of group 2 and the calibration curve obtained in group 1 and the Vickers hardness of group 2 measured by the Vickers hardness tester were strongly correlated with a determination coefficient of 0.99.
CONCLUSIONS
The results demonstrate that HAMILTOM may be a suitable alternative to the conventional method. Unlike the conventional method, which cannot be used for in vivo teeth, HAMILTOM holds potential to quantitatively evaluate the progress of caries in in vivo teeth.
Topics: Cattle; Animals; Hardness; Root Caries; Dentin; Optical Devices; Lactic Acid; Tooth Demineralization; Dental Caries
PubMed: 36273251
DOI: 10.1117/1.JBO.27.10.105004 -
Brazilian Oral Research May 2017This study aimed to evaluate the effect of final irrigation protocols on microhardness reduction and erosion of root canal dentin. Sixty root canals from mandibular...
This study aimed to evaluate the effect of final irrigation protocols on microhardness reduction and erosion of root canal dentin. Sixty root canals from mandibular incisors were instrumented and randomly divided into six groups (n = 10) according to the irrigant used: QMiX, 17% EDTA, 10% citric acid (CA), 1% peracetic acid (PA), 2.5% NaOCl (solution control), and distilled water (negative control). The chelating solutions were used to irrigate the canal followed by 2.5% NaOCl as a final flush. After the irrigation protocols, all specimens were rinsed with 10 mL of distilled water to remove any residue of the chemical solutions. Before and after the final irrigation protocols, dentin microhardness was measured with a Knoop indenter. Three indentations were made at 100 µm and 500 µm from the root canal lumen. Afterwards, the specimens were prepared for scanning electron microscopic analysis and the amount of dentin erosion was examined. Wilcoxon and Kruskal-Wallis tests were used to analyze the results with a significance level set at 5%. At 100 µm, all protocols significantly reduced dentin microhardness (p < .05), while at 500 µm, this effect was detected only in the EDTA and QMiX groups (p < .05). CA was the irrigant that caused more extensive erosion in dentinal tubules, followed by PA and EDTA. QMiX opened dentinal tubules, but did not cause dentin erosion. Results suggest that QMiX and 17% EDTA reduced dentin microhardness at a greater depth. Additionally, QMiX did not cause dentin erosion.
Topics: Biguanides; Citric Acid; Dental Pulp Cavity; Dentin; Edetic Acid; Hardness Tests; Humans; Materials Testing; Microscopy, Electron, Scanning; Peracetic Acid; Polymers; Random Allocation; Reproducibility of Results; Root Canal Irrigants; Root Canal Therapy; Smear Layer; Sodium Hypochlorite; Statistics, Nonparametric; Surface Properties; Tooth Erosion
PubMed: 28513789
DOI: 10.1590/1807-3107BOR-2017.vol31.0040 -
International Journal of Molecular... Aug 2021Understanding the biological and morphological reactions of human cells towards different dentinal derivate grafting materials is fundamental for choosing the type of...
Understanding the biological and morphological reactions of human cells towards different dentinal derivate grafting materials is fundamental for choosing the type of dentin for specific clinical situations. This study aimed to evaluate human periodontal ligament fibroblasts (hPLF) cells exposed to different dentinal derivates particles. The study design included the in vitro evaluation of mineralized dentine (SG), deproteinized and demineralized dentine (DDP), and demineralized dentine (TT) as test materials and of deproteinized bovine bone (BIOS) as the positive control material. The materials were kept with the hPLF cell line, and the evaluations were made after 24 h, 72 h, and 7 days of in vitro culture. The evaluated outcomes were proliferation by using XTT assays, the morphological characteristics by light microscopy (LM) and by the use of scanning electron microscopy (SEM), and adhesion by using confocal microscopy (CLSM). Overall, the experimental materials induced a positive response of the hPLFs in terms of proliferation and adhesion. The XTT assay showed the TT, and the SG induced significant growth compared to the negative control at 7 days follow-up. The morphological data supported the XTT assay: the LM observations showed the presence of densely packed cells with a modified shape; the SEM observations allowed the assessment of how fibroblasts exposed to DDP and TT presented cytoplasmatic extensions; and SG and BIOS also presented the thickening of the cellular membrane. The CLMS observations showed the expression of the proliferative marker, as well as and the expression of cytoskeletal elements involved in the adhesion process. In particular, the vinculin and integrin signals were stronger at 72 h, while the actin signal remained constantly expressed in all the follow-up of the sample exposed to SG material. The integrin signal was stronger at 72 h, and the vinculin and actin signals were stronger at 7 days follow-up in the sample exposed to DDP material. The vinculin and integrin signals were stronger at 72 h follow-up in the sample exposed to TT material; vinculin and integrin signals appear stronger at 24 h follow-up in the sample exposed to BIOS material. These data confirmed how dentinal derivates present satisfying biocompatibility and high conductivity and inductivity properties fundamental in the regenerative processes. Furthermore, the knowledge of the effects of the dentin's degree of mineralization on cellular behavior will help clinicians choose the type of dentine derivates material according to the required clinical situation.
Topics: Animals; Biomarkers; Bone Substitutes; Cattle; Cell Proliferation; Cells, Cultured; Dentin; Fibroblasts; Humans; Integrins; Materials Testing; Microscopy, Confocal; Microscopy, Electron, Scanning; Periodontal Ligament; Vinculin
PubMed: 34445386
DOI: 10.3390/ijms22168681 -
Caries Research 2004The metabolic activity in dental plaque, the biofilm at the tooth surface, is the driving force behind any loss of mineral from the tooth or cavity surface. The symptoms... (Review)
Review
The metabolic activity in dental plaque, the biofilm at the tooth surface, is the driving force behind any loss of mineral from the tooth or cavity surface. The symptoms of the process (the lesion) reflect this activity and can be modified by altering the biofilm, most conveniently by disturbing it by brushing with a fluoride-containing toothpaste. The role of operative dentistry in caries management is to restore the integrity of the tooth surface so that the patient can clean. Thus, the question, 'how clean must a cavity be before restoration?' may be irrelevant. There is little evidence that infected dentine must be removed prior to sealing the tooth. Leaving infected dentine does not seem to result in caries progression, pulpitis or pulp death. However, some of the bacteria survive. What is their fate and if they are not damaging, why is this?
Topics: Dental Caries; Dental Cavity Preparation; Dental Enamel; Dental Plaque; Dental Pulp Exposure; Dental Restoration, Permanent; Dentin; Humans; Pit and Fissure Sealants; Toothbrushing
PubMed: 15153704
DOI: 10.1159/000077770