The effect of saliva contamination on the shear bond strength of orthodontic brackets, at various stages of the bonding procedure using a new self-etch primer was studied. The samples were divided into 4 groups according to 4 different enamel surface conditions: Group A: dry; Group B: saliva contamination before priming; Group C: saliva contamination after priming, and Group D: saliva contamination before and after priming. Stainless steel brackets were bonded in each test group with a light-cured composite resin (TransbondXT 3M). The shear bond strength was determined in the first 30 min after bonding. The analysis of variance indicated that the shear bond strengths of the 4 groups were significantly different (F = 11.89, P < 0.05). Tukey HSD tests indicated that contamination both before and after the application of the acid-etch primer resulted in a significantly lower (=4.6 +/- 1.7 MPa) shear bond strength than either the control group (=8. 8 +/- 1.9 MPa) or the groups where contamination occurred either before ( = 7.9 +/- 2.0 MPa) or after (= 6. 9 +/- 1.5 MPa) the application of the primer. It was concluded that the new acid-etch primer could maintain adequate shear bond strength if contamination occurred either before or after the application of the primer. On the other hand, contamination both before and after the application of the primer could significantly reduce the shear bond strength of orthodontic brackets.
Acid Etching, Dental ; Orthodontic Brackets ; Saliva ; Shear Strength

OBJECTIVETo evaluate the effect of infiltration resin on masking white spot lesions by assessing the change in the white spot area.

METHODSSeventy-four maxillary anterior teeth with post-orthodontic decalcification teeth were investigated in this study. All teeth were treated with infiltration resin according to manufacturer recommendation. Standardized digital images were taken before, immediately after, and one week after treatment. The results were classified into three groups: com-pletely masked, partially masked and unchanged. The images of partially masked teeth were analyzed using an image analysis software. The size of the white spot lesion (W) and the whole-tooth facial surface (T) were measured, and the W:Tratio (%) was calculated. Statistical evaluation of the lesions was performed using Kruskal-Wallis and Mann-Whitney tests.

RESULTSAmong the 74 teeth, 20 (27%) teeth were classified as completely masked and 54 (73%) teeth were classified as partially masked; no tooth was unchanged. The W:T ratio significantly decreased from 39.28% before treatment to 9.46% after treatment (P < 0.05).

CONCLUSIONResin infiltration is an effective treatment for masking white spot lesion. However, the masking effect depends on the lesion depth and activity.

Acid Etching, Dental ; Color ; Dental Caries ; Dental Enamel ; Humans ; Lip ; Tooth Demineralization

OBJECTIVETo investigate the effectiveness of different surface treatments that could promote the bond strength of composite resin to commercially pure titanium.

METHODSThe 24 casting pure titanium specimen were randomly divided into four groups: Smooth group, rough group, acid etching smooth group, acid etching rough group. Each group had six specimens. In the different groups, the specimens were treated respectively under different surface treatments. The specimens of rough group was sandblasted, the acid etching smooth group was treated by acid etching, the acid etching rough group was treated by acid etching after sandblasting, the smooth group had no treatment. After surface treatment, the casting pure titanium specimens that were veneered by composite resin became titanium-composite resin specimen. Then the bond strengths were evaluated by universal testing machine and the surfaces were observed by scanning electron microscope including titanium surface appearance and titanium surface appearance of different groups after shear test.

RESULTSThe bond strengths of smooth group, rough group, acid etching smooth group, acid etching rough group were (3.08 +/- 0.45), (6.05 +/- 0.74), (6.27 +/- 0.80), (10.16 +/- 0.82) MPa, respectively. The statistical analysis showed that the bond strengths in rough group, acid etching smooth group, acid etching rough group were higher than in smooth group (P < 0.01). The highest bond strength was the acid etching rough group. There were no significant differences in the bond strength between rough group and acid etching smooth group (P > 0.05). There were some different titanium surface appearances in each group before and after testing.

CONCLUSIONTitanium surface treatment of sandblasting and etching can improve the bond strength between titanium and composite resin. The pre-treatment of sandblasting before etching is an effective modification method of titanium for bonding to composite resin.

Acid Etching, Dental ; Composite Resins ; Dental Bonding ; Dental Porcelain ; Materials Testing ; Shear Strength ; Surface Properties ; Titanium

Noncarious cervical sclerotic lesions (NCSL) are dental cervical lesions with noncarious sclerotic dentine (NCSD), which appears smooth, hard, and either light yellow or dark brown. Most NCSLs are wedge or dish shaped and commonly occur in canines and premolars, leading to dental hypersensitivity and aesthetic defect. The principal treatment is composite resin restoration; however, many clinical problems, such as retention loss, should not be ignored. NCSL's bonding interface includes NCSD and enamel, and interface pre-treatment can promote the bonding effect. This review summarizes current surface treatment methods and their influence on the bonding effectiveness of NCSL to provide guidance for clinical practice.
Acid Etching, Dental ; Composite Resins ; Dental Bonding ; Dental Restoration, Permanent ; Dentin-Bonding Agents ; Tooth Cervix

OBJECTIVETo compare the microleakage of compomer sealant with non-rinse conditioner and resin sealant with phosphoric acid (35%) by dye test and scanning electron microscope (SEM) observation.

METHODS16 extracted third permanent molars were divided into 4 groups: Group I, non-rinse conditioner (NRC) + Prime & Bond NT + Dyract seal; Group II, phosphoric acid (35%) + Concise sealant; Group III, phosphoric acid (35%) + Dyract seal; Group IV, NRC + Prime & Bond NT + Concise sealant. The teeth were then coated with nail polish, placed in a 50% AgNO3 dye for 18 hours, and sectioned with a diamond saw. SEM observation was performed to evaluate microleakage in the teeth.

RESULTSSilver nitrate penetration was found in each group. The percentage of microleakage in group I was higher than that in group II, and group IV was higher than that in group II (P < 0.01). The percentage of microleakage of resin sealant with phosphoric acid was lower than that in compomer sealant with NRC (P < 0.01). On SEM observation, resin tags and few gaps were found in groups with phosphoric acid. Some gaps and bubbles were found at the bottom of the fissures, particularly in the narrow fissures because of the failure of sealant penetration.

CONCLUSIONResin sealant used with phosphoric acid was better than compomer sealant with NRC on microleakage.

Acid Etching, Dental ; Compomers ; Dental Bonding ; Dentin-Bonding Agents ; Humans ; Maleates ; Molar ; Phosphoric Acids ; Polymethacrylic Acids

OBJECTIVEThis study was to find out the most suitable concentration of added NaF to enough bonding strength of brackets.

METHODSSixty-four teeth were randomly divided into A, B, C and the control group. NaF of four different concentrations (1.23%, 2%, 3% and 0%) was added into 35% phosphoric acid. The four group teeth were etched with four kinds of fluoride etching fluid respectively and were bonded with brackets. Four specimens in each group were selected by turns after 1, 4, 12 and 24 weeks of bonding. The shear bond strength of the teeth were tested, and the adhesive residual index (ARI) of bonding interface were recorded.

RESULTSThe shear bond strength at four test time in each group was no significant (P > 0.05). There was statistical difference of the shear bond strength between four groups (P < 0.05), and group C was lower than the other groups. The ARI was no statistical difference between four groups.

CONCLUSIONThe effects of etching and bonding had no significant changes when the concentration of added NaF was no more than 2%. The shear bond strength decreased while the concentration of NaF was higher than 3%.

Acid Etching, Dental ; Dental Bonding ; Humans ; Orthodontic Brackets ; Phosphoric Acids ; Resin Cements ; Shear Strength ; Surface Properties

OBJECTIVETo find a way to having higher bond strength on mottled enamel.

METHODSSixty mottled enamel first bicuspid teeth extracted from fifteen patients needing orthodontic force were prepared and divided into four groups. Group A was routine acid etched, group B was air abraded, group C was etched by clearfil liner self-etching primer, group D was air abraded and then etched by clearfil liner self-etching primer. Next the bond and resin were used. The shear bond strength was observed and compared. The data were analysed by SPSS 11.5 statistical package.

RESULTSThe shear bonding strength of group A was (2.247 +/- 0.261) MPa, group B was (5.374 +/- 0.469) MPa, group C was (4.345 +/- 0.401) MPa, group D was (5.791 +/- 0.636) MPa. The strengths of four groups were significantly different (P < 0.01). The adhesive remnant index (ARI) scores of the four groups had no significant difference.

CONCLUSIONIn clinic, using air abrasion surface preparation technique is an acceptable way to enhancing the shear bond strength before sticking the orthodontic bonding on dental fluorosis.

Acid Etching, Dental ; Dental Bonding ; Dental Stress Analysis ; Fluorosis, Dental ; Humans ; Orthodontic Brackets ; Resin Cements ; Shear Strength

OBJECTIVEThis study aims to investigate the effects of post-cure heat treatment (PCHT) on the bond strength of Ceramage composite resins for titanium casting using different surface treatments.

METHODSMetal specimens (n=30) were randomly divided into following five groups: polishing (group A), sandblasting (group B), acid etching after sandblasting (group C), PCHT after sandblasting (group D), and PCHT after sandblasting and acid etching (group E). The specimens were then processed and coated with Ceramage composite resins according to the grouping. After treatment, the shear bond strengths and microhardness of the specimens were evaluated. The fracture surface morphology of the titanium-Ceramage composite resin was observed using a scanning electron microscope.

RESULTSThe shear bond strengths of groups A to E were (5.92 +/- 0.54), (10.25 +/- 0.55), (14.97 +/- 0.88), (14.41 +/- 0.63), and (19.95 +/- 0.52) MPa, respectively. No statistical difference was found between groups C and D, whereas the rest of the groups showed statistically significant differences (P < 0.01). Visible polymerization residues were found on titanium porcelain metal surface of groups B to E. The microhardness values of groups D and E were higher than those of groups B and C (P < 0.05).

CONCLUSIONPCHT significantly improves the bond strength and surface microhardness of Ceramage composite resins for titanium casting.

Acid Etching, Dental ; Composite Resins ; Dental Bonding ; Dental Porcelain ; Hot Temperature ; Materials Testing ; Shear Strength ; Silicates ; Surface Properties ; Titanium

OBJECTIVETo compare the retention and caries prevention of fissure sealant on the primary molars etched with self-etching adhesive and phosphoric acid in children.

METHODS43 children younger than 42 months with more than 4 decayed teeth were studied. The split-mouth design was used in this study. The second and/or first primary molars were randomly assigned into self-etching adhesive group in one side of mouth, and phosphoric acid group in the other side. Sealants were applied on 69 pair primary molars according to manufacturer' s instruction with dental cotton-roll isolation. The children were followed up every 3 months, and the sealants were observed and evaluated. In the case caries occurred, the teeth were restored.

RESULTSAfter 3 months, the retention rate was 93% in self-etching adhesive group and 100% in phosphoric acid group. At 6, 12 and 18 months, the retention rate of self-etching adhesive group was statistically lower than that of phosphoric acid group (P<0.05) by Wilcoxon signed ranks test. Caries occurred in both groups and self-etching adhesive group had more caries than phosphoric acid group. Though its retention rate was low, self-etching adhesive was suitable for young children because it was timesaving and its bonding procedures were simple without discomfort rinsing.

CONCLUSIONThe retention rate of sealant with self-etching adhesive was lower than that with phosphoric acid. The phosphoric acid is suitable for pit and fissure sealant. If self-etching adhesive is used for sealing primary molars of young children for a limited period of time, it should be reviewed every 3 months.

Acid Etching, Dental ; Adhesives ; Child ; Dental Bonding ; Dental Enamel ; Humans ; Molar ; Phosphoric Acids ; Pit and Fissure Sealants ; Tooth, Deciduous

Tooth enamel is a complex mineralized tissue consisting of long and parallel apatite crystals configured into decussating enamel rods. In recent years, multiple approaches have been introduced to generate or regenerate this highly attractive biomaterial characterized by great mechanical strength paired with relative resilience and tissue compatibility. In the present review, we discuss five pathways toward enamel tissue engineering, (i) enamel synthesis using physico-chemical means, (ii) protein matrix-guided enamel crystal growth, (iii) enamel surface remineralization, (iv) cell-based enamel engineering, and (v) biological enamel regeneration based on de novo induction of tooth morphogenesis. So far, physical synthesis approaches using extreme environmental conditions such as pH, heat and pressure have resulted in the formation of enamel-like crystal assemblies. Biochemical methods relying on enamel proteins as templating matrices have aided the growth of elongated calcium phosphate crystals. To illustrate the validity of this biochemical approach we have successfully grown enamel-like apatite crystals organized into decussating enamel rods using an organic enamel protein matrix. Other studies reviewed here have employed amelogenin-derived peptides or self-assembling dendrimers to re-mineralize mineral-depleted white lesions on tooth surfaces. So far, cell-based enamel tissue engineering has been hampered by the limitations of presently existing ameloblast cell lines. Going forward, these limitations may be overcome by new cell culture technologies. Finally, whole-tooth regeneration through reactivation of the signaling pathways triggered during natural enamel development represents a biological avenue toward faithful enamel regeneration. In the present review we have summarized the state of the art in enamel tissue engineering and provided novel insights into future opportunities to regenerate this arguably most fascinating of all dental tissues.
Acid Etching, Dental ; Amelogenin ; Biomimetics ; trends ; Dental Enamel ; metabolism ; Dental Enamel Proteins ; Dentistry ; trends ; Tissue Engineering ; methods ; Tooth Remineralization