This study aimed to identify and analyze articles on enamel microabrasion for the treatment of white spot lesions. A search was conducted on the Web of Science. The following parameters were recorded and analyzed: number of citations, year, journal, impact factor, study design, theme, country and continent, institution, authors, and keywords. Data was analyzed using VOSviewer software. The initial search resulted in 1,126 documents, of which 94 articles were included. The highest number of citations an article received was 65. The oldest article was published in 1975, and the most recent in 2023. The most frequent study design was case report (
This study aimed to evaluate the bleaching efficacy and hydrogen peroxide permeability in the pulp chamber by the at-home bleaching gel in protocols applied on different dental surfaces.
Forty premolars were randomly into 4 groups: control group no bleaching, only application on the buccal surface (OB), only application on the lingual surface (OL) and application in buccal and lingual surfaces, simultaneously (BL). At-home bleaching gel (White Class 7.5%) was used for the procedure. The bleaching efficacy was evaluated with a digital spectrophotometer (color change in CIELAB [Δ
All groups submitted to bleaching procedure showed bleaching efficacy when measured with Δ
The application of bleaching gel exclusively on the OB is sufficient to achieve bleaching efficacy, when compared to BL. Although the OL protocol demonstrated lower bleaching efficacy based on the ΔWID values, it may still be of interest and relevant in certain clinical scenarios based on individual needs, requiring clinical trials to better understand its specificities.
The aim of the present study was to evaluate the effect of whitening mouth rinses alone and in combination with conventional whitening treatments on color, microhardness, and surface roughness changes in enamel specimens.
A total of 108 enamel specimens were collected from human third molars and divided into 9 groups (
Statistically significant color change was observed in all groups compared to the CG. All groups, except the LW group, showed statistically significant decreases in microhardness. Roughness showed a statistically significant increase after the treatments, except for the 38% HP group.
Whitening mouth rinses led to a whitening effect when they were used after conventional treatments; however, this process caused major changes on the surface of the enamel specimens.
The aim of this investigation was to give insights into the impact of carbohydrate-electrolyte drinks on the likely capacity of enamel surface dissolution and the influence of human saliva exposure as a biological protective factor.
The pH, titratable acidity (TA) to pH 7.0, and buffer capacity (β) of common beverages ingested by patients under physical activity were analyzed. Then, we randomly distributed 50 specimens of human enamel into 5 groups. Processed and natural coconut water served as controls for testing three carbohydrate-electrolyte drinks. In all specimens, we measured surface microhardness (Knoop hardness numbers) and enamel loss (profilometry, µm) for baseline and after simulated intake cycling exposure model. We also prepared areas of specimens to be exposed to human saliva overnight prior to the simulated intake cycling exposure. The cycles were performed by alternated immersions in beverages and artificial saliva. ANOVA two-way and Tukey HDS tests were used.
The range of pH, TA, and β were 2.85 - 4.81, 8.33 - 46.66 mM/L and 3.48 - 10.25 mM/L × pH, respectively. The highest capacity of enamel surface dissolution was found for commercially available sports drinks for all variables. Single time human saliva exposure failed to significantly promote protective effect for the acidic attack of beverages.
In this study, carbohydrate-electrolyte drinks usually consumed during endurance training may have a greater capacity of dissolution of enamel surface depending on their physicochemical proprieties associated with pH and titratable acidity.
The aim of this
The crowns of 24 extracted sound human molars were sectioned. Sixty enamel specimens (2 × 3 × 4 mm) were selected and divided into five groups (
Significant differences were observed between the study groups. The enamel microhardness changes in Groups 1, 3, 4, and 5 were significantly lower than that of Group 2 (
Within the limitations of this study, it can be concluded that incorporation of each one of the three tested biomaterials as remineralizing agents might be effective in decreasing enamel microhardness changes subsequent to in-office bleaching.
The effects of bone morphogenetic protein-2 (BMP-2) and enamel matrix derivative (EMD) respectively with mineral trioxide aggregate (MTA) on hard tissue regeneration have been investigated in previous studies. This study aimed to compare the osteogenic effects of MTA/BMP-2 and MTA/EMD treatment in MC3T3-E1 cells.
MC3T3-E1 cells were treated with MTA (ProRoot, Dentsply), BMP-2 (R&D Systems), EMD (Emdogain, Straumann) separately and MTA/BMP-2 or MTA/EMD combination. Mineralization was evaluated by staining the calcium deposits with alkaline phosphatase (ALP, Sigma-Aldrich) and Alizarin red (Sigma-Aldrich). The effects on the osteoblast differentiation were evaluated by the expressions of osteogenic markers, including ALP, bone sialoprotein (BSP), osteocalcin (OCN), osteopontin (OPN) and osteonectin (OSN), as determined by reverse-transcription polymerase chain reaction analysis (RT-PCR, AccuPower PCR, Bioneer).
Mineralization increased in the BMP-2 and MTA/BMP-2 groups and increased to a lesser extent in the MTA/EMD group but appeared to decrease in the MTA-only group based on Alizarin red staining. ALP expression largely decreased in the EMD and MTA/EMD groups based on ALP staining. In the MTA/BMP-2 group, mRNA expression of OPN on day 3 and BSP and OCN on day 7 significantly increased. In the MTA/EMD group, OSN and OCN gene expression significantly increased on day 7, whereas ALP expression decreased on days 3 and 7 (
These results suggest the MTA/BMP-2 combination promoted more rapid differentiation in MC3T3-E1 cells than did MTA/EMD during the early mineralization period.
To investigate the effect of enamel matrix derivative (EMD) on periodontal healing of replanted teeth in animal models.
The authors searched MEDLINE, PubMed, EMBASE, Cochrane Library, Web of Knowledge and Scopus for articles published up to Oct 2012. Animal studies in which EMD was applied in transplanted or replanted teeth with adequate controls and histological data were considered. Normal periodontal healing or root resorption determined by histology after EMD was applied in replanted teeth with adequate controls was used as outcome measures. The following search strategy was used: ('Emdogain' OR 'enamel matrix proteins' OR 'enamel matrix derivative') AND ('avulsion' OR 'transplantion' OR 'autotransplantation' OR 'replantation').
Six animal studies were included in the final review. There was great heterogeneity in study design among included studies. Two studies with similar study designs were identified and analyzed by a meta-analysis. The pooled estimates showed a significantly higher normal healing and surface resorption and significantly less inflammatory and replacement resorption in EMD-treated groups compared with non-EMD-treated groups.
With the limitations of this systematic review, the use of EMD led to greater normal periodontal healing and surface root resorption and less inflammatory and replacement root resorption in the presence of periodontal ligaments. However, no definite conclusion could be drawn with regard to the effect of EMD on periodontal healing and root resorption when no periodontal ligaments exist.
The purpose of this study was to compare the microshear bond strength (uSBS) to enamel prepared with different burs and to determine what type of bur were chosen when a self-etching primer adhesive was used.
Enamel of forty-two human molars were used. They were divided into one of six groups (n = 7), Group 1, coarse (125 - 150 µm) diamond bur; Group 2, standard (106 - 125 µm) diamond bur; Group 3, fine (53 - 63 µm) diamond bur; Group 4, extrafine (20 - 30 µm) diamond bur; Group 5, plain-cut carbide bur (no. 245); Group 6, cross-cut carbide bur (no. 557). Clearfil SE Bond and Clearfil AP-X (Kuraray Medical Inc.) was bonded to enamel surface. The bonded specimens were subjected to uSBS testing.
The uSBS of Group 4 was the highest among groups and it was significantly higher than that of Groups 1, 2, 3, and 6 (
Different burs used on enamel surface affected the microshear bond strengths of a self-etching primer adhesive to the enamel surface. In the case of Clearfil SE Bond, extrafine diamond and plain-cut carbide bur are recommended for bonding to enamel.
The purpose of this study was to compare the microshear bond strength (uSBS) of two total-etch and four self-etch adhesive systems and a flowable resin to enamel.
Enamels of sixty human molars were used. They were divided into one of six equal groups (
After enamel surfaces were treated with six adhesive systems, a flowable composite resin (Filek Z 350) was bonded to enamel surface using Tygon tubes. the bonded specimens were subjected to uSBS testing and the failure modes of each group were observed under FE-SEM.
1. The
2. The
3. Adhesive failures in TY and GB group and mixed failures in SB group and SE group were often analysed. One cohesive failure was observed in OS, SB, SE and AP group, respectively.
Although adhesives using the same step were applied the enamel surface, the uSBS of a flowable resin to enamel was different.
The purpose of this study is to observe and compare the remineralization tendencies of artificial enamel caries lesion by remineralization solutions of different degree of saturations at pH 5.5, using a polarizing microscope and computer programs (Photoshop, Image pro plus, Scion Image, Excel).
For this study, 48 sound permanent teeth with no signs of demineralization, cracks, or dental restorations were used. The specimens were immersed in lactic acid demineralization solution for 2 days in order to produce artificial dental caries that consist of surface and subsurface lesions. Each of 9 or 10 specimens was immersed in pH 5.5 lactic acid buffering remineralization solution of four different degrees of saturation (0.507, 0.394, 0.301, and 0.251) for 12 days. After the demineralization and remineralization, images were taken by a polarizing microscope (×100). The results were obtained by observing images of the specimens, and using computer programs, the density of caries lesions were estimated.
While the group with the lowest degree of saturation (0.251) showed total remineralization feature from the surface to the subsurface of the lesion, the group with the highest degree of saturation (0.507) showed demineralization mainly on the surface of the lesion at the constant organic acid concentration 0.01 M and pH 5.5.
The purpose of this study was to compare the microleakage of low and high viscosity flowable resins in class V cavities applied with 1-step adhesives.
Forty class V cavities were prepared on the cervices of buccal and lingual surfaces of extracted molar teeth and divided into four groups (n=8). Cavities were restored with AQ Bond Plus/Metafil Flo α, G-Bond/UniFil LoFlo Plus (Low flow groups), AQ Bond Plus/Metafil Flo and G-Bond/UniFil Flow (High flow group), respectively.
Specimens were immersed in a 2% methylene blue solution for 24 hours, and bisected longitudinally. They were observed microleakages at the enamel and dentinal margins.
In conclusion, the low viscosity flowable resins showed lower marginal microleakage than do the high viscosity flowable resins in class V cavities.
In this study we evaluated the influence of both the thickness of residual enamel and the color of the composite resins applied to lingual surface on the labial surface color.
Background plates were made by randomly (A1, A2, A6D, B1, B2, B3, C1, C2, C6D) selected colors of Filtek Supreme (3M ESPE, St. Paul, U.S.A.) composite resin.
Crown portion of 9 maxillary central incisors were cut off and embedded with acrylic resin except labial surface. Samples of average thickness of 2.2 mm were obtained after cutting it in a thickness of 2.5 mm from the labial surface and sandpaper polish.
The shade of composite resin background was measured using Spectrophotometer (Spectrolino® GretagMacbeth, Regensdorf, Switzerland). And CIE L*a*b* value of 2.2 mm thickness tooth samples were measured on the 9 composite resin backgrounds. And then, the cutting side of tooth samples was ground to the extent of 1.9 mm, 1.6 mm, 1.3 mm, 1.0 mm and placed on composite resin backgrounds and measured L*a*b* values with the same method.
In all samples, L* value and b* value seemed to have a tendency of decreasing as thickness of tooth sample becomes thinner regardless of background colors (p < 0.05). But, a* value didn't show the significant differences depending on the thickness.
The purpose of this study is to observe and compare the dynamic change of artificially demineralized enamel by remineralization solutions of different degrees of saturation at pH 4.3.
In this study, 30 enamel specimens were demineralized artificially by lactic acid buffered solution. Each of 10 specimens was immersed in pH 4.3 remineralization solution of three different degrees of saturation (0.22, 0.30, 0.35) for 10 days. After demineralization and remineralization, images were taken by a polarizing microscope (× 100). The density of lesion were determined from images taken after demineralization and remineralization.
During remineralization process, mineral deposition and mineral loss occurred at the same time. After remineralization, total mineral amount and width of surface lesion increased in all groups. The higher degree of saturation was, the more mineral deposition occurred in surface lesion and the amount of mineral deposition was not much in subsurface lesion. Total demineralized depth increased in all groups.
The purpose of this study was to compare the normal and two times of application time of six self-etching primers applied to enamel using microshear bond strength (uSBS) test and the finding of scanning electronic microscope (SEM).
Crown of sixty human molars were bisected mesiodistally and buccal and lingual enamel of crowns were partially exposed and polished with 600 grit SiC papers. They were divided into one of two equal groups subdivided into one of six equal groups (n = 10) by self-etching primer adhesives.
After the same manufacture's adhesive resin and composites were bonded on the enamel surface of each group, the bonded specimens were subjected to uSBS testing and also observed under SEM.
In conclusion, generally two times of primer application time increased the enamel uSBS, especially with the statistical increase of bond strength in adhesives involving high-pH primers.
The purpose of this study was to evaluate the effect of passive or active application of primer and coat times of bond on the shear bond strength when a self-etching primer adhesive (Clearfil SE Bond) was applied to enamel surface.
Crowns of sixteen human molars were selected. Buccal and lingual enamels of crowns were partially exposed and slabs of 1.2 mm thick were made. They were divided into one of four equal groups (n = 8). Group 1: passive application of Primer and 1 coat of Bond, Group 2: active application of Primer and 1 coat of Bond, Group 3: passive application of Primer and 2 coats of Bond, Group 4: active application of Primer and 2 coats of Bond. Clearfil AP-X was bonded to enamel suface of each group using Tygon tubes. The bonded specimens were subjected to microshear bond strength (
The results of this study were as follows;
The There was not statistically significant interaction between enamel There was not statistically significant difference between enamel There was statistically significant difference between enamel
Since it was reported that incipient enamel caries can be recovered, previous studies have quantitatively evaluated that enamel artificial caries have been remineralized with fluoride, showing simultaneously the increase of width of surface layer and the decrease of width of the body of legion. There is, however, little report which showed that remineralization could occur without fluoride. In addition, the observations on the change of hydroxyapatite crystals also have been scarcely seen.
In this study, enamel caries in intact premolars or molars was induced by using lactic acidulated buffering solutions over 2 days. Then decalcified specimens were remineralized by seven groups of solutions using different degree of saturation (0.212, 0.239, 0.301, 0.355) and different pH (5.0, 5.5, 6.0) over 10 days. A qualitative comparison to changes of hydroxyapatite crystals after fracturing teeth was made under SEM (scanning electron microscopy) and AFM (atomic force microscopy).
The results were as follows:
1. The size of hydroxyapatite crystals in demineralized area was smaller than the normal ones. While the space among crystals was expanded, it was observed that crystals are arranged irregularly.
2. In remineralized enamel area, the enlarged crystals with various shape were observed when the crystals were fused and new small crystals in intercrystalline spaces were deposited.
3. Group 3 and 4 with higher degree of saturation at same pH showed the formation of large clusters by aggregation of small crystals from the surface layer to the lesion body than group 1 and 2 with relatively low degree of saturation at same pH did. Especially group 4 showed complete remineralization to the body of lesions. Group 5 and 6 with lower pH at similar degree of saturation showed remineralization to the body of lesions while group 7 didn't show it. Unlike in Group 3 and 4, Group 5 and 6 showed that each particle was densely distributed with clear appearance rather than crystals form clusters together.
Dental caries is the most common disease in the oral cavity. However, the mechanism and treatment of dental caries is not completely understood since many complex factors are involved. Especially the effect of pH on remineralization of early stage of dental caries is still controversial.
In this study, dental caries in dentin was induced by using lactic acidulated buffering solutions and the loss of inorganic substance was measured. Also decalcified specimens were remineralized by three groups of solution with different pH (group of pH 4.3, 5.0, and 5.5). Then, the amount and the area of inorganic substance precipitation was quantitatively analyzed with microradiograph. Also a qualitative comparison of the normal phase, the demineralized phase, and the remineralized phase of hydroxyapatite crystal was made under SEM.
The results were as follows;
In microradiograghic analysis, as the pH increased, the amount of remineralization in decalcified dentin tended to increase significantly. As the pH decreaced, deeper decalcification, however, occurred along with remineralization. The group of pH 5.5 had a tendency to be remineralized without demineralization (p < 0.05). In SEM view, the remineralization in dentine caries occurred from the hydroxyapatite crystal surface surrounding the mesh of organic matrix, and eventually filled up the demineralized area. 5 days after remineralization, hydroxyapatite crystal grew bigger with deposition of inorganic substance in pH 4.3 and 5.0 group, and the crystal in the remineralized area appeared to return to normal. After 10 days, the crystals in group of pH 4.3 and 5.0, which grew bigger after 5 days of remineralization, turned back to their normal size, but in group of pH 5.5, some crystals were found to double their size.
In according to the results of this experiment, the decalcifying and remineralizing process of dentine is neither simple nor independent, but a dynamic process in which decalcification and remineralization occur simultaneously. The remineralization process occurred from the hydroxyapatite crystal surface.
This study compared the microshear bond strength (µSBS) of light-cured and dual-cured composites to enamel bonded with three self-etching adhesives. Crown segments of extracted human molars were cut mesiodistally, and 1 mm thickness of specimen was made. They were assigned to three groups by used adhesives: Xeno group (Xeno III), Adper group (Adper Prompt L-Pop), and AQ group (AQ Bond). Each adhesive was applied to cut enamel surface as per manufacturer's instruction. Light-cured (Filtek Z 250) or dual-cured composite (Luxacore) was bonded to enamel of each specimen using Tygon tube.
After storage in distilled water for 24 hours, the bonded specimens were subjected to µSBS testing with a crosshead speed of 1 mm/minute. The mean µSBS (n = 20 for each group) was statistically compared using two-way ANOVA, Tukey HSD, and t test at the 0.05 probability level. The results of this study were as follows;
1. The µSBS of light-cured composite was significantly higher than that of dual-cured composite when same adhesive was applied to enamel.
2. For Z 250, the µSBS of AQ group (9.95 ± 2.51 MPa) to enamel was significantly higher than that of Adper goup (6.74 ± 1.80 MPa), but not significantly different with Xeno group (7.73 ± 2.01 MPa).
3. For Luxacore, the µSBS of Xeno group (5.19 ± 1.32 MPa) to enamel was significantly higher than that of Adper goup (3.41 ± 1.19 MPa), but not significantly different with AQ group (4.50 ± 0.96 MPa).
The objective of this
Microhardness (Microhardness tester, Zwick) of each specimen was measured at the baseline of pre-treatment, immediate after bleaching treatment, 14 days after bleaching treatment and Knoop Hardness Number was determined. Microhardness changes of experimental groups were compared.
The results show that tooth whitening strip and gel used in this study does not effect the micro-hardness of enamel during bleaching procedure.
The purposes of this study were to compare the effects of one or two applications of all-in-one adhesives on microtensile bond strengths (µTBS) to unground enamel and to investigate the morphological changes in enamel surfaces treated with these adhesives using a scanning electron microscopy (SEM).
Twenty-five noncarious, unrestored human mandibular molars were used. The unground enamel surfaces were cleansed with pumice. The following adhesives were applied to lingual, mid-coronal surfaces according to manufacture's directions; Clearfil SE bond in SE group, Adper Prompt L-Pop™1 coat in LP1 group, 2 coats in LP2 group, Xeno® III 1 coat in XN1 group, and 2 coats in XN2 group. After application of the adhesives, a hybrid light-activated resin composite was built up on the unground enamel. Each tooth was sectioned to make a cross-sectional area of approximately 1.0 mm2 for each stick. The microtensile bond strength was determined. Each specimen was observed under SEM to examine the morphological changes. Data were analyzed with one-way ANOVA.
The results of this study were as follows;
1. The microtensile bond strength values were; SE (19.77±2.44 MPa), LP1 (13.88±3.67 MPa), LP2 (14.50±2.52 MPa), XN1 (14.42±2.51 MPa) and XN2 (15.28±2.79 MPa). SE was significantly higher than the other groups in bond strength (p < 0.05). All groups except SE were not significantly different in bond strength (p < 0.05).
2. All groups were characterized as shallow and irregular etching patterns.
Recently, self-etching adhesive system has been introduced to simplify the clinical bonding procedures. It is less acidic compared to the phosphoric acid, thus there is doubt whether this system has enough bond strength to enamel. The purpose of this study was to investigate the influence of additional etching on the adhesion of resin composite to enamel.
Ninety extracted bovine permanent anterior teeth were used. The labial surfaces of the crown were ground with 600-grit abrasive paper under wet condition. The teeth were randomly divided into six groups of 15 teeth each. Clearfil SE Bond®, Adper™ Prompt L-Pop and Tyrian SPE™ were used as self-etching primers. Each self-etching primers were applied in both enamel specimens with and without additional etching. For additional etching groups, enamel surface was pretreated with 32% phosphoric acid (UNI-ETCH, Bisco, Inc., Schaumburg, IL, USA). Hybrid resin composite Clearfil AP-X, (Kuraray Co., Ltd., Osaka, Japan) was packed into the mold and light-cured for 40 seconds. Twenty-four hours after storage, the specimens were tested in shear bond strength. The data for each group were subjected to independent
In Clearfil SE Bond®, shear bond strength of additional etching group was higher than no additional etching group (
In conclusion, self-etching adhesive system with weak acid seems to have higher bond strength to enamel with additional etching, while self-etching adhesive system with strong acid seems not.
This study compared the microshear bond strength (µSBS) to end and side of enamel rod bonded by four adhesives including two total etch adhesives and two self-etch adhesives.
Crown segments of extracted human molars were cut mesiodistally. The outer buccal or lingual surface was used as specimens cutting the ends of enamel rods, and inner slabs used as specimens cutting the sides of enamel rods.
They were assigned to four groups by used adhesives: Group 1 (All-Bond 2), Group 2 (Single Bond), Group 3 (Tyrian SPE/One-Step Plus), Group 4 (Adper Prompt L-Pop). After each adhesive was applied to enamel surface, three composite cylinders were adhered to it of each specimen using Tygon tube. After storage in distilled water for 24 hours, the bonded specimens were subjected to µSBS testing with a crosshead speed of 1 mm/minute. The results of this study were as follows;
1. The µSBS of Group 2 (16.50 ± 2.31 MPa) and Group 4 (15.83 ± 2.33 MPa) to the end of enamel prism was significantly higher than that of Group 1 (11.93 ± 2.25 MPa) and Group 3 (11.97 ± 2.05 MPa) (p < 0.05).
2. The µSBS of Group 2 (13.43 ± 2.93 MPa) to the side of enamel prism was significantly higher than that of Group 1 (8.64 ± 1.53 MPa), Group 3 (9.69 ± 1.80 MPa), and Group 4 (10.56 ± 1.75 MPa) (p < 0.05).
3. The mean µSBS to the end of enamel rod was significantly higher than that to the side of enamel rod in all group (p < 0.05).
This study was done to evaluate whether vital bleaching agents could influence on the translucency of the bovine enamel. The anterior bovine teeth that were extracted one day before and without any gross discoloration were obtained and then were preserved in physiologic saline. 6 mm cylindrical tooth specimens were fabricated with diamond puncher perpendicularly on labial surface of bovine tooth. After embedded in transparent acrylic resin with labial surface being exposed, they were cut to a thickness of 1.2 mm with low speed diamond saw (Isomat, Buehler Co., Lake Bluff, IL, USA). They were smoothly ground to 1 mm thickness of enamel with sandpaper. 24 specimens were randomly divided into 3 groups and control group respectively. Opalescence (10% carbamide peroxide, Ultradent, South Jordan, USA), Rembrandt (10% carbamide peroxide, DenMat, USA) and Opalescence F (15% carbamide peroxide with fluoride, Ultradent, USA) were applied on labial sides of the bovine enamel for 7 days (bleaching agents were reapplied every 24 hours) and the opposite surface was contacted to cotton that soaked in distilled water. The control group was soaked in distilled water. Three stimulus value X, Y and Z were evaluated with colorimeter (Color & Color Differencemeter, Model TC-6FX, Tokyo Denshoku Co., Japan) on the labial surface of all specimen three times on white and black background plate before the bleaching agents were applied and on 3rd, 5th and 7th day after applied. The degree of translucency was normally assessed by measuring the inverse property, opacity (contrast ratio).
10% Opalescence, 15% Opalescence-F, and control group showed no significant variation in the translucency of bovine enamel, However Rembrandt decreased the translucency of it (p < 0.01).
The purpose of this study was to evaluate the etching effects and bond strength of total etching and self-etching adhesive system on unground enamel using scanning electron microscopy and microtensile bond strength test.
The buccal coronal unground enamel from human extracted molars were prepared using low-speed diamond saw. Scotchbond Multi-Purpose (group SM), Clearfil SE Bond (group SE), or Adper Prompt L-Pop (group LP) were applied to the prepared teeth, and the blocks of resin composite (Filtek Z250) were built up incrementally. Resin tag formation was evaluated by scanning electron microscopy, after removal of enamel surface by acid dissolution and dehydration. For microtensile bond strength test, resin-bonded teeth were sectioned to give a bonded surface area of 1mm2. Microtensile bond strength test was perfomed.
The results of this study were as follows.
1. A definite etching pattern was observed in Scotchbond Multi-Purpose group.
2. Self-etching groups were characterized as shallow and irregular etching patterns.
3. The results (mean) of microtensile bond strength were SM; 26.55 MPa, SE; 18.15 MPa, LP; 15.57 MPa. SM had significantly higher microtensile bond strength than SE and PL (p < 0.05), but there was no significant differance between SE and PL.
This study evaluated the marginal microleakage of five single step adhesives. Class V cavity preparations with occlusal margins in enamel and gingival margins in dentin were prepared on both buccal and lingual surfaces of extracted human molar teeth. Prepared teeth were randomly divided into five groups and restored using one of the single step adhesives and composite resins: Prompt L-Pop/Filtek Z-250 (Group 1), AQ Bond/Metafil CX (Group 2), One-Up Bond F/Palfique Toughwell (Group 3), Futurabond/Admira (Group 4), Xeno III/Spectrum TPH (Group 5).
The restored teeth were thermocycled. Microleakage was assessed by dye penetration using 2% methylene blue dye solution. The teeth were bisected buccolingually and evaluated for microleakage under steromicroscope. The data were statistically analysed by Kruskal-Wallis test and Mann-Whitney tests.
The results of this study were as follows;
Microleakage of enamel margins in group 3 was statistically higher than that in groups 1, 2, 4, 5 (p < 0.05). Microleakage of dentin margins in group 1 was statistically higher than that in groups 2, 5, and that in group 3 was statistically higher than that in groups 2, 4, 5 (p < 0.05). Dentin marginal microleakage was higher than enamel marginal microleakage in all experimental groups.
In conclusion, Prompt L-Pop showed the least leakage at enamel margin, and AQ Bond showed at dentin margin in this study. Marginal miroleakage in dentin was higher than that in enamel.
This study was done to present a criterion in selection of the most proper light sources and materials by measuring metamerism index(MI) of the light curing composite resins with spectrocolorimeter. Metamerism is defined when two objects appear to be the same color in one illuminant but different in another. This is due to the fact that they have different spectral curves that fail to match under the second illuminant.
In this study, A1 & A3 shade of five light curing composite resins (Esthet-X, Filteck Z250, Filteck A110, Charisma, Vitalescence) were chosen based on Vita shade. Five samples were made for shade of each product with Teflon mold (diameter: 15mm, thickness: 2mm).
Metamerism index of each samples on a Barium sulfate plate (L*=96.54, a*=0.19, b*=0.01) prepared for sample fixation were measured with spectrocolorimeter(Miniscan XE plus, Model 4000s, Hunter Lab, USA) by applying standard light source D65, C, Fcw, TL84 and A. Standardization was done with reference standard (X=80.8, Y=85.7, Z=90.8) and light trap. The results were as follows.
Different resins with same Vita shade showed recognizable color difference(ΔE*>2). All composites had MI below accepted value 0.5 between standard illuminant(D65, C, & A) and below 1.5 under fluorescent condition (Fcw & TL84). MI value between D65 and A showed higher value than MI value between other source of light(p<0.01). All resins except Z250 showed MI value that A3 is higher than A1 between D65 and A(p<0.05).
The purpose of this study is to evaluate the effect of additional enamel etching with phosphoric acid on the microleakage of the adhesion of self-etching primer system.
Class V cavity(4 mm×3 mm×1.5 mm) preparations with all margins in enamel were prepared on buccal surface of 42 extracted human upper central incisor teeth. Prepared teeth were randomly divided into 3 groups.
Group 1 : no additional pretreatment with 37% phosphoric acid (NE).
Group 2 : additional pretreatment with 37% phosphoric acid for 10 seconds (E10s).
Group 3 : additional pretreatment with 37% phosphoric acid for 20 seconds (E20s).
The adhesives(Clearfil SE Bond®, Kuraray, Osaka, Japan) and composite resins(Clearfil AP-X®, Osaka, Kuraray, Japan) were applied following the manufacturer's instructions. All the specimens were finished with the polishing disc(3M dental product, St Paul, MN, USA), thermocycled for 500 cycles between 5℃ and 55℃ and resected apical 3-mm root. 0.028 stainless steel wire was inserted apically into the pulp chamber of each tooth and sealed into position with sticky wax. Surrounding tooth surface was covered with a nail varnish 2 times except areas 1 mm far from all the margins. After drying for one day, soaked the samples in the distilled water. Microleakage was assessed by electrochemical method(System 6514, Electrometer®, Keithley, USA) in the distilled water.
In this study, the microleakage was the lowest in group 1(NE) and the highest in group 3(E20s)(NE<E10s<E20s). But no statistically significant differences were found(p=0.5).
On the basis of findings from this experiment, it can be concluded that additional enamel etching has no influence on the microleakage of the adhesion of self-etching primer system.
Dental caries is a chronic disease that causes the destruction of tooth structure by the interaction of plaque bacteria, food debris, and saliva.
There has been attempts to induce remineralization by supersaturating the intra-oral environment around the surface enamel, where there is incipient caries.
In this study, supersaturated remineralized solution "R" was applied to specimens with incipient enamel caries, and the quantitative ananlysis of remineralization was evaluated using microradiography. Thirty subjects volunteered to participate in this study. Removable appliances were constructed for the subjects, and the enamel specimen with incipient caries were embedded in the appliances. The subjects wore the intra-oral appliance for 15 days except while eating and sleeping.
The removable appliance were soaked in supersaturated solution "R", saline, or Senstime® to expose the specimen to those solutions three times a day, 5 minutes each time. After 15 days, microradiography was retaken to compare and evaluate remineralization.
The results were as the following:
1. The ratio of remineralized area to demineralized area was significantly higher in the supersaturated solution "R" and Senstime® than in the saline. (p<0.05)
2. Remineralization in the supersaturated buffer solution "R" occurred in the significantly deeper parts of the tooth, compared to the Senstime® group containing high concentration of fluoride.(p<0.05)
As in the above results, the remineralization effect of remineralized buffer solution "R" on incipient enamel caries has been proven. For clinical utilization, further studies on soft tissue reaction and the effect on dentin and cementum are necessary.
In conclusion compared to commercially available fluoride solution, remineralization solution "R" showed better remineralization effect on early enamel caries lesion, so it is considered as effecient solution for clinical application.