Dental bleaching on teeth submitted to enamel microabrasion 30 years ago-a case report of patients' compliance during bleaching treatment.

OBJECTIVES: The present dental bleaching case report describes a new method that precisely quantifies the daily wearing-times of the bleaching product by inserting a microsensor in the acetate custom tray. The bleaching efficacy was also discussed since the patient was previously submitted to enamel microabrasion. METHODS: The patient was submitted to enamel microabrasion in 1987, and bleaching treatment was performed in 2005. In 2017, re-bleaching was executed using 10% peroxide carbamide. The electronic microsensor, TheraMon (TheraMon® microelectronic system; Sales Agency Gschladt, Hargelsberg, Austria), was embedded in the labial region of the upper and lower acetate trays to evaluate the wearing-times of the acetate trays/bleaching product. The patient was instructed to wear the tray for 6 to 8 h/day while sleeping. After 24 days of bleaching treatment, the data obtained from the TheraMon electronic devices was collected and interpreted. RESULTS: The patient did not entirely follow the bleaching treatment as recommended, as there was no evidence of use of the upper and lower trays for some days; additionally, the bleaching product was used for shorter and longer periods than was instructed. CONCLUSIONS: The TheraMon microeletronic device precisely measured the wearing-times of the acetate tray/bleaching product during the bleaching treatment. Teeth submitted to enamel microabrasion presented with a healthy clinical appearance after 30 years. CLINICAL SIGNIFICANCE: Measuring the length and frequency of use of an acetate tray/bleaching product can be important to clinicians and patients for obtaining a controlled and adequate bleaching treatment.

Auxiliary UV light devices for removal of fluorescent resin residues after bracket debonding.

OBJECTIVE: The purpose of this clinical report was to describe the detection of fluorescent resin residue after orthodontic bracket debonding with two UV light devices and analyze the surface morphology of enamel after 1 year. CLINICAL CONSIDERATIONS: A 22-year-old woman had orthodontic brackets removed by a previous dentist; however, resin residue was left on the enamel of the maxillary teeth. After confirming the fluorescent property of the resin, different protocols were used for each half of the maxillary arch. The first method, a black light lens was attached to a light-curing device to detect resin fluorescence, followed by polishing with silicone rubber tips. The second method used a light emitting diode light system attached to and activated by a high-speed handpiece, followed by polishing with discs. Both methods were completed with diamond polishing paste applied with felt discs. Polyvinyl siloxane impressions were made initially, after residue removal, after finishing and after polishing for morphologic analysis. The results were evaluated with photographs and the scanning electron microscope images made of resin casts from the impressions. A follow-up was made after 1 year. CONCLUSIONS: Both methods yielded a satisfactory clinical outcome, with a smooth surface, acceptable surface gloss and minimal tooth wear. The use of a UV device that excites fluorescence is recommended for the controlled removal of resin residue on enamel. CLINICAL SIGNIFICANCE: The controlled removal of resin residue from enamel after orthodontic treatment is challenging but can be improved with auxiliary methods for detecting resin residues. This clinical report describes two types of devices that excite fluorescent resins in a more rapid and precise technique to guide the practitioner in the controlled removal of residual resin on teeth.

Biomechanical performance of three fiberglass post cementation techniques: Imaging, in vitro, and in silico analysis.

PURPOSE: The structural integrity of the resin cement layer, the bond strength, and the biomechanical behavior of different fiberglass post cementation techniques were evaluated. METHODS: Thirty-three bovine incisors were divided into three groups (n = 11): conventional fiberglass post (CFP), conventional fiberglass post in flared root canals (CFL), and relined fiberglass post (RFP). Six specimens from each group were submitted for high-resolution microcomputed tomography (µCT) to evaluate the integrity and presence/volume of voids at the resin cement layer. Finite element analysis (FEA) of two three-dimensional (3D) models of each group were conducted, one considered ideal (without interface defects) and another containing the conditions identified in the µCT analysis. Push-out bond strength tests were conducted for all specimens. RESULTS: The CFL group had the greatest mean values of void (Thirds cervical: 73.67; middle: 95.67; apical: 47.33) and gap concentration (Thirds cervical: 14.67; middle: 15.83; apical: 8.33) compared with CFP and RFP. A significant difference in bond strength was observed between the cervical (1.33 MPa) and middle thirds (1.85 MPa) compared with the apical third (4.85 MPa) of the CFL. A significant difference was observed in the bond strength in the CFL (1.33 MPa) and RFP (3.29 MPa) in the cervical third, which were statistically similar to the bond strength of the CFP. The tensile stress distributions were similar in most structures, localized in the cervical region on the lingual surface. CONCLUSIONS: Structural defects in the interface layer might influence the bond strength and biomechanical behavior under the different fiberglass post cementations.

Influence of daily usage times on patients' compliance during at-home bleaching: a randomized clinical trial.

The effectiveness of at-home dental bleaching treatments depends on the time that bleaching products are in contact with the teeth surface and, consequently, on the adequate use of associated custom acetate trays. OBJECTIVE: This randomized single-blinded trial aimed to analyze if the daily usage time of these products influences the patient's compliance behavior when submitted to monitored at-home dental bleaching. Secondary outcomes were color change and tooth sensitivity. METHODOLOGY: Sixty-six volunteers were randomly distributed into three groups (n=22): patients were instructed to use the trays for 2 (G2), 4 (G4), and 8 (G8) hours daily. The daily dental bleaching compliance behavior was measured using a microsensor inserted into the trays. Subjective and objective color evaluation assessments were adopted at baseline (T0), one (T1), two (T2), and three weeks (T3) after the beginning of the bleaching treatment, as well as two weeks after the treatment (T4). Tooth sensitivity was analyzed using the VAS scale, ranging from T1 to T4. RESULTS: G2 showed a greater degree of cooperation than G8 and cooperation was inversely proportional to the recommended usage time. Significantly higher color change was observed in the upper arch for G8 when compared to G2 in subjective analysis, from T1 to T4. There were no statistical differences between the groups in objective analysis. CONCLUSION: Shorter recommended usage time of the bleaching product may improve the patient's compliance with at-home dental bleaching treatments. However, increased daily usage time may promote better subjective color change. Bleaching sensitivity was more significant in the first week for a longer time of use.

Use of auxiliary devices during retreatment of direct resin composite veneers.

The removal of direct composite veneers, when the retreatment is necessary, represents a challenge to the clinician, since the healthy dental structure must be preserved. Thus, the aim of this study was to compare the accuracy provided by different auxiliary devices during retreatment of direct composite veneers. Seventy-five bovine teeth were prepared for direct composite veneers, scanned (T1), and restored. Specimens were divided into 5 groups for retreatment: conventional high-speed handpiece without auxiliary device (WD); high-speed handpiece with a white LED (WL); high-speed handpiece with an UV light (UL); electric motor and multiplier 1/5 handpiece (EM); and conventional high-speed handpiece using magnifying loupe (ML). After retreatments, other scanning was performed (T2). Changes on dental wear or composite residues areas, as well as, the average between wear and presence of residues were measured. Data were submitted to Kruskal-Wallis and Dunn's post-test (p≤ 0.05). There were greater areas of wear for ML, being statistically superior to WD and EM groups. The ML presented smaller residues areas, being statistically lower than the WD and EM groups. Regarding the average between wear and the presence of resin residues, additional wear occurred after re-preparation, regardless of the group. Magnifying loupe promoted greater areas of wear and smaller areas of resin residues than conventional high-speed handpiece and electric motor. Both techniques using light accessories did not differ from other ones.

Reestablishment of occlusion with prosthesis and composite resin restorations.

Here, we present a case report on prosthetic reconstruction of posterior teeth and composite resin restoration of anterior teeth yielding considerable esthetic improvement, reestablishment of disocclusion guides and function.

Correlation of the hybrid layer thickness and resin tags length with the bond strength of a self-etching adhesive system.

The objective of this study was to measure the thickness of the hybrid layer (HLT), length of resin tags (RTL) and bond strength (BS) in the same teeth, using a self-etching adhesive system Adper Prompt L Pop to intact dentin and to analyze the correlation between HLTand RTL and their BS. Ten human molars were used for the restorative procedures and each restored tooth was sectioned in mesio-distal direction. One section was submitted to light microscopy analysis of HLT and RTL (400x). Another section was prepared and submitted to the microtensile bond test (0.5 mm/min). The fractured surfaces were analyzed using scanning electron microscopy to determine the failure pattern. Correlation between HLT and RTL with the BS data was analyzed by linear regression. The mean values of HLT, RTL and BS were 3.36 microm, 12.97 microm and 14.10 MPa, respectively. No significant relationship between BS and HLT (R2= 0.011, p>0.05) and between BS and RTL (R2= 0.038) was observed. The results suggested that there was no significant correlation between the HLT and RTL with the BS of the self-etching adhesive to dentin.

Esthetic recovery of teeth presenting fluorotic enamel stains using enamel microabrasion and home-monitored dental bleaching.

This clinical report describes the enamel microabrasion technique for removing maxillary and mandibular hard fluorotic enamel stains followed by home-monitored home dental bleaching. The removal of fluorotic enamel stains utilized macroabrasion with a water-cooled, fine-tapered 3195 FF diamond bur followed microabrasion with the application of Prema Compound (Premier Dental Products Co, Norristown, PA, USA). Home-monitored dental bleaching was performed 14 days after enamel microabrasion using a 10% carbamide peroxide gel for 2 h/day. The wearing time of the acetate tray/dental bleaching was quantified by a microsensor from TheraMon microelectronic system (Sales Agency Gschladt, Hargelsberg, Austria) that was completely embedded in the acetate trays. The teeth were bleached effectively during 23 days. The mean wearing time of the acetate trays/dental bleaching product was 1.54 h/day, for the upper and lower arches. The patient reported satisfaction with the treatment. The association of enamel microabrasion and home dental bleaching was an excellent clinical treatment for teeth affected with enamel fluorosis.

Length of resin tags in pit-and-fissure sealants: all-in-one self-etching adhesive vs phosphoric acid etching.

PURPOSE: To investigate the penetration (tags) of adhesive materials into enamel etched with phosphoric acid or treated with a self-etching adhesive, before application of a pit-and-fissure sealant. MATERIALS AND METHODS: The sample comprised six study groups with six specimens each. Before pit-and-fissure sealing with the materials Clinpro SealantTM (Groups I and II), Vitro Seal ALPHA (Groups III and IV) and Fuji II LC (Groups V and VI), the teeth in Groups I, III, and V were etched with 35% phosphoric acid for 30 seconds. Teeth in Groups II, IV, and VI received application of the self-etching adhesive Adper Prompt L-Pop. The treated teeth were sectioned buccolingually, ground to 100-microm thickness, decalcified, and analyzed by conventional light microscopy at 400x magnification. RESULTS: The teeth etched with phosphoric acid exhibited significantly greater penetration than specimens treated with self-etching adhesive. CLINICAL SIGNIFICANCE: When compared with enamel treated with a self-etching adhesive, the penetration (tags) of adhesive materials into enamel was greater when applied on enamel etched with phosphoric acid.

In vitro-evaluation of secondary caries formation around restoration.

The objective of this in vitro study was to evaluate demineralization around restorations. Class V preparations were made on the buccal and lingual surfaces of each tooth. TPH (Group 1), Fuji II LC (Group 2), Tetric (Group 3), Dyract (Group 4), GS 80 (Group 5) and Chelon Fil (Group 6) were randomly placed in equal numbers of teeth. The teeth were submitted to a pH-cycling model associated with a thermocycling model. Sections were made and the specimens were examined for the presence of demineralization under polarized light microscopy. Demineralization was significantly reduced with Chelon Fil (Group 6). Furthermore, a similar inhibitory effect on the development of demineralization was observed in Groups 2, 4 and 5.

Influence of daily usage times on patients' compliance during at-home bleaching: a randomized clinical trial

Abstract The effectiveness of at-home dental bleaching treatments depends on the time that bleaching products are in contact with the teeth surface and, consequently, on the adequate use of associated custom acetate trays. Objective This randomized single-blinded trial aimed to analyze if the daily usage time of these products influences the patient's compliance behavior when submitted to monitored at-home dental bleaching. Secondary outcomes were color change and tooth sensitivity. Methodology Sixty-six volunteers were randomly distributed into three groups (n=22): patients were instructed to use the trays for 2 (G2), 4 (G4), and 8 (G8) hours daily. The daily dental bleaching compliance behavior was measured using a microsensor inserted into the trays. Subjective and objective color evaluation assessments were adopted at baseline (T0), one (T1), two (T2), and three weeks (T3) after the beginning of the bleaching treatment, as well as two weeks after the treatment (T4). Tooth sensitivity was analyzed using the VAS scale, ranging from T1 to T4. Results G2 showed a greater degree of cooperation than G8 and cooperation was inversely proportional to the recommended usage time. Significantly higher color change was observed in the upper arch for G8 when compared to G2 in subjective analysis, from T1 to T4. There were no statistical differences between the groups in objective analysis. Conclusion Shorter recommended usage time of the bleaching product may improve the patient's compliance with at-home dental bleaching treatments. However, increased daily usage time may promote better subjective color change. Bleaching sensitivity was more significant in the first week for a longer time of use.

Clinical assessment of postoperative sensitivity in posterior composite restorations.

This incidence of postoperative sensitivity was evaluated in resin-based posterior restorations. Two hundred and ninety-two direct restorations were evaluated in premolars and molars. A total of 143 Class I and 149 Class II restorations (MO/OD and MOD) were placed in patients ranging in age from 30 to 50 years. After the cavity preparations were completed, a rubber dam was placed, and the preparations were restored using a total-etch system (Prime & Bond NT) and a resin-based restorative material (TPH Spectrum). The patients were contacted after 24 hours and 7, 30 and 90 days postoperatively and questioned regarding the presence of sensitivity and the stimuli that triggered that sensitivity. The Chi-square and Fisher's Exact Test were used for statistical analysis. Evaluation at 24 hours after restorative treatment revealed statistically significant differences among the types of cavity preparations restored and the occurrence of postoperative sensitivity (p = 0.0003), with a higher frequency of sensitivity in Class II MOD restorations (26%), followed by Class II MO/DO (15%) and Class I restorations (5%). At 7, 30 and 90 days after restorative treatment, there was a decrease in the occurrence of sensitivity for all groups. The percentage of sensitivity among the groups was not significantly different. This study shows that the occurrence of sensitivity is correlated with the complexity of the restoration.

Considerations about enamel microabrasion after 18 years.

PURPOSE: To review of the current status of enamel microabrasion method and its results 18 years after the development and application of this method. METHODS: A technique performing enamel microabrasion with hydrochloric acid mixed with pumice and other techniques employing a commercially available compound of hydrochloric acid and fine-grit silicon carbide particles in a water-soluble paste have been described. Much has been learned about the application of this esthetic technique, long-term treatment results and microscopic changes to the enamel surface that has significant clinical implications. The latest treatment protocol is presented and photographic case histories document the treatment results. Clinical observations made over 18 years are discussed. RESULTS: According to our findings, the dental enamel microabrasion technique is a highly satisfactory, safe and effective procedure.

Efficacy of auxiliary devices for removal of fluorescent residue after bracket debonding.

OBJECTIVE: To evaluate four protocols for removal of fluorescent materials after bracket debonding. MATERIALS AND METHODS: Resin removal from 40 bovine enamel surfaces was performed according to groups (n = 10): conventional (C), white LED (W), LED that evidenced fluorescence (F), and fluorescent lens (FL). The following analyses were performed: sample thickness, superficial area of resin residue, and areas of resin residue or worn enamel in depth. ANOVA and Tukey tests were used to analyze sample thickness (P ≤ .05). Area measurements were analyzed by Kruskal-Wallis and Dunn's tests (P ≤ .05). RESULTS: The FL group showed the highest reduction in enamel thickness. F group final thickness was similar to that of other groups. The largest superficial areas of resin residue were found for the C and W groups, while the FL group had the greatest removal of resin residue. The C group exhibited the largest area in depth of resin residue. The FL and F groups exhibited the most loss of enamel with the least amount of resin residue; in contrast, the C and W groups presented the fewest areas of worn enamel and the most areas of resin residue. CONCLUSION: Auxiliary devices were useful for removal of fluorescent residue after bracket debonding.

Two-Year Clinical Evaluation of a Nanofilled Etch-and-Rinse and a Self-Etch Adhesive System Containing MDPB and Fluoride in Non-carious Cervical Lesions.

OBJECTIVES: The aim of this clinical study was to evaluate the performance of restorations for non-carious cervical lesions performed with a two-step etch-and-rinse or with a two-step self-etch adhesive. MATERIALS AND METHODS: The teeth to be restored (15 patients, N = 90 restorations) were randomly assigned into 3 groups (n = 30), according to the adhesive system: group 1 (G1): Peak LC Bond; group 2 (G2): Clearfil Protect Bond; and group 3 (G3): prior selective acid etching of the enamel margins before bonding with Clearfil Protect Bond. The NCCLs were restored with Amelogen Plus composite resin. Two calibrated examiners evaluated the restorations using modified US Public Health Service criteria. The data of retention, marginal integrity, and marginal discoloration were analyzed using the Kruskal-Wallis and Wilcoxon tests. RESULTS: There were no significant differences in clinical performance among the groups for the variables: retention, marginal integrity, and marginal discoloration after 1 year and 2 years. The alpha rates after 2 years were: 93.3% for G1 and 96.7% for G2 and G3 for retention; 93.3%, 100%, and 90% for G1, G2, and G3 for marginal discoloration; 86.7%, 96.7%, and 90% for G1, G2, and G3 for marginal integrity, respectively. CONCLUSIONS: The adhesives presented similar clinical performance at the end of 2 years. Also, the prior etching with phosphoric acid did not significantly improve the clinical performance of self-etch adhesive.

Tooth enamel properties and morphology after microabrasion: an in situ study.

AIM: This study evaluated the effect of saliva on enamel after microabrasion with different microabrasive compounds under in situ conditions. METHODS: Enamel/dentin blocks (16 mm2 ) from bovine incisors were divided into nine groups (n = 19): one control group (no treatment), four groups treated with microabrasion using 35% phosphoric acid (H3 PO4 ) + pumice, and the last four groups treated with microabrasion using 6.6% hydrochloric acid (HCl) + silica. The treated groups were subdivided according to the in situ regimen: without salivary exposure, 1 h, 24 h, or 7 days of saliva exposure. Surface microhardness (SMH) and cross-sectional microhardness (CSMH) were tested. Scanning electron microscopy (SEM) was used to evaluate enamel morphology. Microhardness data were tested by analysis of variance, and Tukey's and Dunnett's tests (α = 0.05). RESULTS: The SMH analysis revealed that all the microabrasion-treated groups presented significantly-reduced SMH values when compared to the control group (P < 0.05). Treatment with HCl + silica was more prone to the effect of saliva than H3 PO4 + pumice, even for CSMH analysis, once the superficial layers reached the same microhardness of that of the control group (P > 0.05). These results were confirmed by SEM, which demonstrated the mineral recovery effect over time. CONCLUSION: Saliva was effective in promoting the rehardening of enamel after microabrasion, mainly for the surfaces treated with HCl + silica.