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Objectives:The finishing of the gingival floor and its margins is regarded to be necessary in Class II cavities, so the aim of this research was to evaluate 4 finishing systems for the cervical margins of Class II cavities, with regard to surface roughness and waviness.Methods:Eighty Class II cavities were prepared in 20 intact molars by a single operator, using a diamond-coated bur (granulometry 80 μm) mounted on a parallelometer, under magnification (5x, Zeiss) in order to reduce variability. In every tooth, 4 different finishing methods were randomly applied: A: carbide bur; B: straight hand chisel; C: diamond-coated bur 60 μm; and D: diamond-coated sonic instrument. After that, the gingival floor of each cavity was analysed with an optical profilometer. Mean surface roughness (Ra) and mean surface waviness (Wa) were evaluated with an optical device. Results were analysed with ANOVA after ln-transformation of data. One- and two-way ANOVA was applied.Results:There was no statistically significant difference between the 4 test groups for Ra which was in the range between 0.76 and 0.92 μm. For Wa, the diamond bur produced significantly lower waviness values (mean Wa 5.2 μm) than the other three instruments (mean Wa between 5.7 and 7.7 μm). The variability of Ra and especially Wa was very high: the coefficient of variation of Ra was between 23% and 38%, that of Wa between 52 and 57%.Conclusions:As there was no difference between the four instruments considering surface morphology, the efficient and safe sonic instruments should be chosen over the other three instruments for finishing proximal boxes of Class II cavities. [ABSTRACT FROM AUTHOR]

This prospective clinical study evaluated the survival of indirect, posterior fiber-reinforced composite fixed dental prosthesis (FRC FDP). Between June-1999 and June- 2000, 58 patients received 65 FCR FDPs made of unidirectional E-glass fibers (Vectris) veneered with resin composite (Signum) that were adhesively cemented (Variolink II). The evaluation protocol involved technical (chipping, debonding or fracture of tooth/restoration) and biological failures (caries, endodontic complications). Altogether, 6 technical failures were observed after a mean observation time of 180 months (survival rate: 89.2%, Kaplan-Meier) in the form of fractures (n=2) and partial debondings (n=4). All defective restorations were repaired or recemented. Secondary caries occurred in one patient after 11 years. The 3-unit posterior FRC FDPs showed good clinical survival rate up to 15 years of clinical function. Limited numbers of experienced failures were due to mainly debonding followed by fracture of the veneering composite.g composite., (Copyright© 2024 Dennis Barber Ltd.)

Purpose: This randomized, split-mouth clinical study evaluated the marginal quality of direct class-I and class-II restorations made of microhybrid composite that were applied using two polymerization protocols and two marginal evaluation criteria., Materials and Methods: A total of 50 patients (mean age: 33 years) received 100 direct class-I or class-II restorations in premolars or molars. Three calibrated operators made the restorations. After conditioning the tooth with 2-step etch-and-rinse adhesive, restorations were made incrementally using microhybrid composite. Each layer was polymerized using a polymerization device operated either in regular mode (600-650 mW/cm2 for 20 s) (RM) or high-power (1200-1300 mW/cm2 for 10 s) mode (HPM). Two independent, calibrated operators evaluated the restorations 1 week (baseline) and 6 months after restoration placement, and thereafter annually up to 10 years using modified USPHS and SQUACE criteria. Data were analyzed using the Mann-Whitney U-test (α = 0.05)., Results: Alpha scores (USPHS) for marginal adaptation (76% and 74% for RM and HPM, respectively) and marginal discoloration (70% and 72%, for RM and HPM, respectively) did not show significant differences between the two polymerization protocols (p > 0.05). Alpha scores (SQUACE) for marginal adaptation (78% and 74% for RM and HPM, respectively) and marginal discoloration (70% for both RM and HPM) were also not significantly different at the 10-year year follow-up (p > 0.05)., Conclusion: Regular and high-power polymerization protocols had no influence on the stability of marginal quality of the microhybrid composite tested up to 10 years. Both modified USPHS and SQUACE criteria confirmed that regardless of the polymerization mode, marginal quality of the restorations deteriorated significantly compared to baseline (p < 0.05).

A comparison of the abilities of rotary versus reciprocating files to eliminate viable Enterococcus faecalis populations from the long oval root canals of extracted human teeth. Fifty teeth were contaminated and randomly distributed into two groups (n = 25 each): BT-RaCe group and WaveOne group. Two microbial samples were obtained from each tooth before (S1) and after (S2) instrumentation. The CFUs from the S1 and S2 measurements were calculated and compared between the groups. Both groups showed significantly fewer CFUs in the S2 samples (P < 0.001). In the S2 intragroup comparison, BT-RaCe resulted in significantly fewer CFUs than WaveOne (P = 0.010). In the direct comparison between the rotary multiple file shaping system and the reciprocating single-file system, the multiple file system was more efficient at reducing the microbiological load of viable E. faecalis from long oval root canals., (© 2017 Australian Society of Endodontology Inc.)

Comparison of the ability of newly designed rotary files to eliminate viable Enterococcus faecalis populations from long oval root canals of extracted human teeth to that of the self-adjusting file (SAF). One hundred caries-free, single-rooted, long oval teeth were contaminated with E. faecalis. The teeth were randomly distributed into four groups (n = 25) as follows: G.1, manual; G.2, SAF; G.3, ProTaper Next; and G.4, BT-Race. Two microbial samples were obtained from each tooth with sterile paper points, (s1) before and (s2) after instrumentation. The relative reduction in colony-forming units (CFUs) from s1 to s2 measurements was calculated and compared among the groups using parametric Kruskal-Wallis one-way anova on ranks and Dunn's method (a = 0.05). The results indicated a descending order of the groups with regard to efficacy as follows: BT-Race, Next, SAF and manual. The statistical analysis showed that the relative percentage reduction (RR) of CFUs was lower in the manual group than in the other groups, while the SAF group showed a significantly lower RR than the BT-Race group (P < 0.05). The efficacy in reduction of the microbiological load of viable E. faecalis from long oval root canals was different between the tested endodontic systems., (© 2016 Australian Society of Endodontology Inc.)

Background: Non carious cervical lesions associated to muscle hyperfunctions are increasing. Microhybrid resin composites are used to restore cervical abfractions. The purpose of this study was to investigate if resin composites modify tooth plaque, inducing an increment of cariogenic microflora and evaluate their effect, in vivo and in vitro , against S. mutans ., Material and Methods: Eight abfractions were restored with two microhybrid resin composites (Venus, Heraeus-Kulzer® and Esthet-X, Dentsply®), after gnatological therapy, in three patients with muscle hyperfunctions. For each abfraction three samples of plaque were taken from the cervical perimeter: before the restoration, one week and three months after restoration. The samples were evaluated both by traditional microbiological methods and by Polymerase Chain Reaction (PCR). In vitro , disk-shaped specimens of the two composites were prepared to estimate the effects against pre-cultured S. mutans , after incubation at 37°C for 24h and assessed by a turbidimetric technique., Results: In vivo no differences were found in plaque growth, for all samples, before and after restoration with both composites; in vitro , instead, a significant reduction of S. mutans growth was found between specimens of two composites (Mann-Whitney U-test p >0,06)., Conclusions: In this study a relevant consideration was elicited: composite materials, in vivo , do not modify plaque composition of non carious cervical lesions to a potential cariogenic plaque. Key words: Abfraction, restoration, S. mutans, composite, class V., Competing Interests: The authors declare that they have no conflict of interest.

Aim: Aim of the study was to evaluate the long-term reliability and effectiveness of inlays and onlays in ceramic and composite material, examining scientific studies published from 2004 to 2013. The results of this review were analyzed and compared with the important literature review proposed by Manhart in 2004., Methods: With this review it was possible to analyze a total sample of 5858 Class I and II restorations, made in the posterior region: 5295 ceramic and 563 composite restorations in 2377 patients. Works were evaluated using USPHS, modified USPHS and CDA criteria after a mean observation period of 5.4 years (5.9 years for ceramic restorations, 2.6 for composite restorations)., Results: The arithmetic average of success was 94%, higher in ceramic restorations (94.9%) than composite materials (91.1%). The weighted average success rate was 95.3%, 92.8% for composite restorations and 96.3% for ceramic ones. The highest rates of success were found in ceramic restorations notwithstanding the longer observation period., Conclusion: Indirect restorations have a low failure rate and they prove to be an excellent choice in the treatment of both class I and II lesions. During the last 6 years, the parameters related to these restorations have improved, with a 4% increase of success.

This study aimed to determine the effect of adhesive direct composite restorations, endodontic treatments, and fatigue treatments on the cuspal deflection of maxillary premolars subjected to different cyclic occlusal forces. Thirty intact maxillary second premolars were selected. Ten teeth were left untreated (group IN), 10 teeth were subjected to endodontic and restorative treatment (group FL), and the remaining 10 teeth were subjected to endodontic, restorative, and fatigue treatments (group FT). All teeth were subjected to 5 occlusal compressive loading forces (98, 147, 196, 245, and 294 N) with a universal testing device. A total of 15 experimental groups were obtained with 3 tooth conditions (IN, FL, FT) and 5 different occlusal loading values. Deflection amounts (μm) were measured with laser sensors and recorded, and obtained data were statistically analyzed with one-way analysis of variance at a significance level of .05. Mean cuspal deflection values (μm) and SDs of experimental groups ranged as follows: IN-98 (24.4 ± 19.8), IN-147 (34.8 ± 28.9), IN-196 (43.8 ± 34.7), IN-245 (54.5 ± 46.4), IN-294 (60.3 ± 50.6), FL-98 (56 ± 49.1), FL-147 (62.6 ± 49.6), FL-196 (72.4 ± 52.1), FL-245 (81.3 ± 56), FL-294 (92.2 ± 60.9), FT-98 (77.2 ± 80.9), FT-147 (83.4 ± 81.3), FT-196 (92.6 ± 83.7), FT-245 (102.7 ± 85.4), and FT-294 (124.2 ± 89.5). Mean values of three main experimental groups were as follows: IN (43.5 μm), FL (72.9 μm) and FT (96.0 μm). Significant differences were found between the three main groups and relevant subgroups (P < .001). Highest cuspal deflection values (CDV) were obtained in FT groups. Lowest CDV were obtained in IN groups. FL groups showed higher deflection values than IN groups. CDV increased progressively as the teeth were restored and subjected to fatigue treatment.

Objectives: This randomised, split-mouth clinical study evaluated the marginal quality of direct Class I and Class II restorations made of microhybrid composite and applied using two polymerisation protocols, using two margin evaluation criteria., Methods: A total of 50 patients (mean age: 33 years) received 100 direct Class I or Class II restorations in premolars or molars. Three calibrated operators made the restorations. After conditioning the tooth with 2-step etch-and-rinse adhesive, restorations were made incrementally using microhybrid composite (Tetric EvoCeram). Each layer was polymerised using a polymerisation device operated either at regular mode (600-650 mW/cm(2) for 20s) (RM) or high-power (1200-1300 mW/cm(2) for 10s) mode (HPM). Two independent calibrated operators evaluated the restorations 1 week after restoration placement (baseline), at 6 months and thereafter annually up to 5 years using modified USPHS and SQUACE criteria. Data were analyzed using Mann-Whitney U-test (α=0.05)., Results: Alfa scores (USPHS) for marginal adaptation (86% and 88% for RM and HPM, respectively) and marginal discoloration (88% and 88%, for RM and HPM, respectively) did not show significant differences between the two-polymerisation protocols (p>0.05). Alfa scores (SQUACE) for marginal adaptation (88% and 88% for RM and HPM, respectively) and marginal discoloration (94% and 94%, for RM and HPM, respectively) were also not significantly different at 5th year (p>0.05)., Conclusion: Regular and high-power polymerisation protocols had no influence on the marginal quality of the microhybrid composite tested up to 5 years. Both modified USPHS and SQUACE criteria confirmed that regardless of the polymerisation mode, marginal quality of the restorations deteriorated compared to baseline., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Aim: Aim of this study was to evaluate two different luting cements and how their clinical procedures influence the postcementation quality., Methods: Thirty-six freshly extracted mono-radicular teeth (N.=18) were treated endodontically and randomly divided into two groups. Posts were cemented respectively with two different self adhesive luting cements: Group A - RelyX Unicem (3M Espe) and Group B - Multilink Sprint (Ivoclar-Vivadent) following the manufacturers' instructions. Teeth were then thermocycled according to protocol ISO/TR 11405 and were immersed 24 hours in 2% methylene-blue solution. Each tooth was sectioned by a diamond-coated saw (Isomet-Buhler) from CEJ to apex. Each slice was examined for the presence or absence of gutta-percha remnants, voids, bubbles, dye infiltration degree and polymerization grade of the luting agent. Findings were evidenced by stereoscopic microscopy (30x) and Micro-Raman spectroscopy. Mann-Whitney and ANOVA statistical analyses were performed for all results., Results: No statistical significances were evidenced for gutta-percha presence, dye infiltration and polymerization degree. Voids were present mostly in Group B and bubbles in Group A. Both differences were statistically significant., Conclusion: Materials and protocols for glass fiber posts cementation are fundamental for the clinical success. Self adhesive luting cements, if used correctly, could be an acceptable and quick luting agent for postcementation.

Aim: The degree of conversion of a luting composite cement influences its clinical performance. Aim of the study was to evaluate the degree of conversion of 4 different composite cements by means of micro Raman spectrophotometry., Methods: Forty-four cylindrical onlays of different and defined thickness (1, 2, 3, 4 mm) were built using a custom made template. The onlays were made in composite material (Signum, Heraeus; shade A 3,5) and cemented onto a glass plate with different luting materials: dual curing (Variolink II, Calibra) and light curing (Venus flow, Tetric flow). The lamp tip was shielded in order to have the light reach the cement only through the onlay. Samples were divided into 12 groups (N.=3), differing in onlay thickness and luting material. Each sample was examined in three spots by a micro-Raman spectrophotometer (Dilor Hr-Labram). The conversion degree was evaluated by analyzing the variations in intensity of the 1638 cm(-1) aliphatic peak (C=C), characteristic of all Bis-GMA containing materials, related to the invariant 1608 cm(-1) (C-C of the aromatic ring)., Results: All materials show good polymerisation results below 1 mm and 2 mm onlays. Below onlays thicker than 3 mm a constant degree of conversion throughout the surface of samples could not be found: spots with satisfactory polymerisation and spots with insufficient polymerisation were found., Conclusions: Onlay thickness has a key role in cement conversion. The thicker the onlay, the less predictable the conversion.

Over the last few years, the advancements made in the field of adhesive techniques have significantly modified operative techniques, from cavity preparation to final restoration. On one hand, a predictable bond between restoration and dental tissues allows us to operate with very conservative techniques, saving sound dental tissue; on the other hand, it must be considered that such procedures are not simple. Additionally, it is easy to observe that all of our everyday dental practice is strictly influenced by the type of material and techniques used. Knowing such procedures as well as adhesive mechanisms, quality of sound dental tissue and its conservation - both in vital and endodontically treated teeth - is now considered significantly relevant for restorative purposes.