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This study aimed to evaluate the effect of chlorhexidine (CHX) application on etched dentin on the 6-month retention of restorations placed on non-carious cervical lesions (NCCLs). A randomized controlled split-mouth and triple blind trial was carried out. Patients (n=42) with at least two non-carious cervical lesions were included. NCCLs were randomly assigned to two groups: control (placebo solution) or test group (2% CHX solution for 60 s after acid etching and before the adhesive application). Class V restorations (n=169) were performed with an etch-and-rinse adhesive system and composite resin by 10 trained operators. A calibrated examiner evaluated the restorations at 1 week (baseline) and at 6 months using the FDI criteria. The primary outcome was retention of the restorations. The analysis of factors associated to failure of restorations was carried out by Fisher's exact test (α=0.05). After 6 months of follow-up, 3.4% (CI 95% 1.3-7.3) of the restorations failed. There was no statistically significant difference between control and CHX (p=0.920). Regarding the cavity variables, deeper (p=0.04), wider (p=0.004) and wedge-shaped (p=0.033) cavities failed more. Both treatments provided acceptable clinical performance of the restorations. The use of CHX as a adjuvant in dentin adhesion did not influence the retention of Class V restorations after 6 months of follow-up.

For years, the treatment for the replacement of a missing tooth was a fixed dental prosthesis. Currently, implants are indicated to replace missing teeth due to high clinical success and with the advantage of not performing preparations in the adjacent tooth. Another option for space closure is the use of orthodontics associated to miniscrews for anchorage allowing better control of the orthodontic biomechanics and especially making possible closure of larger prosthetic spaces. Thus, this article describes two cases with indications and discussion of the advantages and disadvantages of using orthodontics for prosthetic spaces closure. The cases herein presented show that it is possible to close an space when there are available teeth in the adjacent area. It can be concluded that when a malocclusion is present there will be a strong trend to indicate space closure by orthodontic movement as it preserves natural teeth and seems a more physiological approach.

Objectives: This randomised clinical trial assessed how biofilm development and composition is affected by time and denture material type in denture wearers with and without denture stomatitis., Methods: Specimens of acrylic resin (control) and denture liners (silicone-based or acrylic resin based, depending on the experimental phase) were inserted into the surface intaglio of 30 denture wearers. Biofilm was formed in two phases of 21 days, and counts of viable micro-organisms in the accumulating biofilm were determined after 7, 14 and 21 days of biofilm formation. Data were analysed by three-way ANOVA followed by Tukey test to assess differences among health condition (healthy or with denture stomatitis), materials and time point., Results: Non-albicans Candida species counts were higher in diseased patients with silicone-based denture liners (p=0.01). Denture stomatitis patients showed higher mutans streptococci counts after 7 days (p=0.0041)., Conclusions: Longer biofilm formation time periods did not result in differences on biofilm composition. The denture liners evaluated in this study accumulate greater amount of biofilm, and therefore their use should be carefully planned., Clinical Significance: The silicone-based denture liner tested should be used cautiously in patients with denture stomatitis as it showed increased non-albicans species counts, known to be difficult to treat., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

The preservation of teeth to support an attachment-retained overdenture is an appropriate and stable alternative to extractions and complete dentures. A key to success is the strategic selection of teeth for retention. This clinical report discusses a method for fabricating an overdenture based on a combination of direct and indirect impression techniques. This technique is a simple and time-efficient alternative to traditional methods that aids in overcoming difficulties in fabricating overdentures., (Copyright © 2013 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.)

Objectives: The presence of cariogenic biofilm could result in surface degradation of composite and ionomeric restorative materials. Thus, this study evaluated in situ the alterations in the surface microhardness of these materials under biofilm accumulation and cariogenic challenge., Methods: In a split-mouth, double-blind, cross-over study, 10 volunteers wore palatal intra-oral devices containing bovine enamel slabs restored with composite resin (CR - Z250) or resin-modified glass ionomer (RMGI - Vitremer). Two phases of 14 days were carried out, one for each restorative material. In one side of the device, biofilm was allowed to accumulate under a plastic mesh, whereas in the opposing side, regular brushing was carried out 3 times/day with a dentifrice containing 1100 μg F/g as NaF. A 20% sucrose solution was applied extra-orally 10×/day on each restored dental slab. Knoop microhardness was used to calculate the percentage of surface hardness loss (%SHL)., Results: All materials showed a decrease in surface hardness after the in situ period. The restorative materials presented the following average for %SHL: RMGI without biofilm accumulation=8.9 and with biofilm accumulation=25.6, CR without biofilm accumulation=14.7 and with biofilm accumulation=17.0., Conclusion: Biofilm accumulation and the presence of cariogenic challenge promoted faster degradation of ionomeric materials, but this was not observed for composite resin., Clinical Significance: The oral environment affects the surface hardness of aesthetic restorative materials. Biofilm accumulation and cariogenic challenge promote surface degradation for ionomeric materials, but not for composite resin., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Objectives: The aim of this study was to evaluate the influence of investment type on the color of feldspathic ceramics., Methods: Ceramic specimens were constructed using the refractory die technique, using four investments (i.e., Vitadurvest, Duravest, Duceralay Superfit, and Fortune) to observe their effect on the color of five commercially available ceramics (i.e., Super Porcelain EX-3, Vision Esthetic, Vintage Halo, IPS Classic, and Vitadur Alpha). The color analysis of the ceramics was performed with a colorimeter using the CIE L*a*b* color coordinates., Results: The investments produced significant alterations on a*, b*, and L* color parameters of the ceramics tested. The ceramic Vision Esthetic was influenced by the type of investment in all color parameters (P<.05). Two investments (Duravest and Fortune) produced alterations in color parameters with three of the five ceramics tested., Conclusions: The investment materials produced alterations on the ceramic color parameters, resulting in unacceptable chromatic alterations (ΔE*).

Objectives: The aim of this study was to assess the influence of various ceramic thicknesses and luting agents on color variation in five ceramic systems., Methods: Fifteen disc-shaped ceramic specimens (11 mm diameter; shade A3) were fabricated with each of the six veneering ceramics tested, with 1, 1.5, or 2 mm thickness (n=5). Resin composite discs (Z-250, shade C4) were used as bases to simulate a chromatic background. The cementation of the veneers was carried out with an opaque resin-based cement (Enforce, shade C4), a resin-based cement (Enforce, shade A3), or without cement (C4, control group). Color differences (ΔE*) were determined using a colorimeter. Three-way ANOVA was used to analyze the data, followed by a Tukey post-hoc test (α=.05)., Results: The L*a*b* values of the ceramic systems were affected by both the luting agent and the ceramic thickness (P<.05). In general, there was no difference between the control group and the group using the resin-based cement. The use of an opaque luting agent resulted in an increase of the color coordinates a*, b*, L*, producing differences in ΔE* values for all ceramics tested, regardless of the thickness (P<.05). For the 2-mm thick veneers, higher values in the color parameters were obtained for all ceramics and were independent of the luting agent used., Conclusions: The association of 2-mm thickness with opaque cement presented the strongest masking ability of a dark colored background when compared to a non- opaque luting agent and the other thicknesses tested.

The aim of this study was to determine the extent to which repeated firings would change the color of feldspathic ceramics. Specimens were fabricated from five commercially available feldspathic ceramics using a circular stainless steel matrix 11 mm in diameter and 1.0 mm thick (n = 10, shade = A3). Repeated firings were performed and color analysis was completed with a colorimeter using the CIELA B color coordinates. Two-way ANOVA was used to analyze the data, followed by Tukey's post-hoc test (a = 0.05). Three factors were used as determinants: a, a measure of the chroma along the red-green axis; b, a measure of the chroma along the yellow-blue axis; and L, a measure of the lightness-darkness of the specimen on a scale from 0 (black) to 100 (white). The results indicated that a and b values increased and L values decreased after repeated firings, resulting in reddish, yellowish, and darker specimens, respectively (P = 0.001). As the number of firings increased, significant color alterations occurred in the color parameters of the specimens. These alterations resulted in color changes (delta E) that could be considered unacceptable in clinical practice.

An implant-retained overdenture is less expensive than a fixed implant-retained prosthesis; however, using ball attachments on abutments that are nonparallel and/or outside the path of insertion may result in loss of retention. As described in this case report, alignment devices can be used as a mandibular overdenture retainer to diminish the lack of parallelism between two implants. The treatment plan involved the use of an alignment device on each implant to ensure correct alignment among ball attachments and its retentive component. These devices can be used to fabricate overdentures retained by implants that are misaligned by as much as 14 degrees.

This study sought to evaluate how the type of cavity preparation and indirect restorative material affected the fracture resistance of maxillary premolars. Teeth were divided into seven groups (n = 14) according to the cavity preparation design (inlays, partial onlays with palatal canine coverage, and total onlays with coverage of both canines) and restorative material used. After the teeth were prepared, restorations were manufactured using a ceramic or a composite resin and cemented with a resin-based cement, with the exception of a control group consisting of sound premolars with no preparation. Fracture resistance was assessed using a universal testing machine with a 9 mm steel ball at a speed of 0.5 mm/minute until fracture. ANOVA results showed significant differences between restorative materials and types of preparations (p < 0.05). Cavity design did not affect composite resin restorations, while ceramic restorations with partial and total canine coverage presented the lowest fracture resistance values (p < 0.05). Within the limitations of this study, the authors concluded that indirect composite resin restorations offered better performance than ceramic restorations, regardless of the cavity design.

Purpose: To evaluate in situ the effect and mechanisms involved in the anticariogenic effect of a calcium glycerophosphate fluoride dentifrice., Methods: In a double-blind, crossover design, a non-F dentifrice (negative control), a F dentifrice and a F dentifrice containing 0.13% CaGP were compared regarding the inhibition of enamel demineralization. Both F dentifrices contained 1500 microg F/g (w/w) as sodium monofluorophosphate (MFP). Bovine enamel blocks were mounted in contact with a S. mutans test plaque, in palatal appliances worn by 10 volunteers. 30 minutes after treatment with the dentifrices, a sucrose rinse was performed and enamel demineralization was assessed after an additional 45 minutes., Results: No significant difference was observed among groups in the calcium and inorganic phosphate concentrations in the fluid phase of the test plaque 30 minutes after the dentifrice use (P > 0.05), but F concentration was significantly higher for both F dentifrices (P < 0.05). Also, the dentifrices did not differ regarding the pH before or 5 minutes after the sugar challenge (P > 0.05). A higher mineral loss was observed for the non-F dentifrice group (P < 0.05), but no significant difference was observed between the F dentifrices containing CaGP or not (P > 0.05). Using this in situ model, the findings suggested that CaGP at the concentration tested did not enhance the inhibition of enamel demineralization promoted by F dentifrice.

Since there is a lack of information on the surface properties of composite restorations achieved with standard polishing procedures after aging processes, this study evaluated the effects of immediate (IM) and delayed (DE) polishing on the surface roughness (Ra), microhardness (KHN) and microleakage (ML) of microfilled (Filtek A110) and hybrid (Filtek Z250) resin composites after one-year storage. Standardized preparations were made on the buccal surface of 256 bovine teeth, where half were restored with each composite. For each composite, the specimens were randomly allocated to two subgroups. The first group (IM) was polished immediately after gross finishing using three different systems/techniques (n=16): Sof-Lex, Flexicups and Flexicups + Jiffy Polishing Brush + Flexibuffs (sequential), then stored for three weeks in saline. The DE group was stored for two weeks, polished with the same systems and stored for one week. From each subgroup, eight specimens were assessed after three weeks regarding Ra, KHN and ML (baseline), andthe eight remaining specimens were stored for one year before analysis. The data were analyzed (alpha=0.05) with ANOVA, paired Student's t-test (Ra and KHN) or Kruskal-Wallis and Signed Rank tests (microleakage). After one year, microfilled resin composite specimens showed the lowest Ra and KHN (p<0.05). N o differencein microleakage was observed among the different groups (p>0.05). The sequential technique provided the lowest roughness and Sof-Lex the lowest hardness (p<0.05). IM showed similar or better performance than DE for ML and Ra (p<0.05). In conclusion, aging increased the composites Ra and ML in all experimental conditions (p<0.05).

This study aimed to determine the influence of surface roughness (Ra), surface free energy (SFE), saliva, and bacteria on Candida adhesion to denture materials. The Ra and SFE of 2 acrylic resin specimens and 2 denture liner specimens were measured and assayed in a flow chamber for bacteria culture perfusion plus Candida albicans or C glabrata cultures. Adhesion was determined by counting under light microscopy. Candida adhesion showed significant differences depending on the factors involved. The overall colonization was significantly decreased by saliva and influenced by bacteria. Candida adhesion was strongly affected by Ra, saliva, and bacteria, but not by SFE.