Biomaterial investigations in dentistry最新文献

{"title":"Effect of Nd:YAG and Er:YAG laser tooth conditioning on the microleakage of self-adhesive resin cement.","authors":"Azita Kaviani,&nbsp;Niloofar Khansari Nejad","doi":"10.1080/26415275.2021.1990063","DOIUrl":"https://doi.org/10.1080/26415275.2021.1990063","url":null,"abstract":"<p><strong>Statement of problem: </strong>Recently, the application of lasers in restorative dentistry has been considered for cavity preparation and surface conditioning of enamel and dentin. However, the beneficial effects of cavity surface conditioning by laser irradiation on microleakage are still controversial.</p><p><strong>Purpose: </strong>This study aimed to compare the microleakage of self-etch adhesive resin cement with Nd:YAG and Er:YAG laser tooth surface conditioning to evaluate the capabilities of these lasers as a reliable replacement for etching cavities.</p><p><strong>Materials and methods: </strong>Fifty-four class V cavities were prepared on the buccal and lingual surfaces of 27 sound human premolar teeth. The samples were randomly divided into three groups (<i>n</i> = 18): group 1: no conditioning; group 2: conditioned with Er:YAG laser (2940 nm, 10 Hz, 1.2 W); group 3: conditioned with Nd:YAG laser (1064 nm, 1.5 W, 10 Hz). All the cavities were filled with self-adhesive resin cement. After curing and polishing, the samples were immersed in 2% methylene blue solution for 24 h, and after being embedded in acrylic resin, they were sectioned longitudinally and examined under a stereomicroscope. The data were submitted to Kruskal-Wallis and Dunn tests (α = 0.05).</p><p><strong>Results: </strong>The lowest microleakage mean rank was observed in the Er:YAG group (19.19), and the highest mean rank was noted in the Nd:YAG group (33.08), with significant differences between the three groups (<i>P</i>-value = .01). Pairwise comparisons demonstrated significant differences between the Er:YAG and Nd:YAG groups (<i>P</i>-value = .004) as well as Er:YAG and no conditioned groups (<i>P</i>-value =.022).</p><p><strong>Conclusion: </strong>The irradiation of the Er:YAG laser (2940 nm, 10 Hz, 1.2 W) on cavity surface resulted in less marginal microleakage of self-etch adhesive resin cement restorations compared to Nd:YAG (1064 nm, 1.5 W, 10 Hz) and no conditioning groups.</p>","PeriodicalId":72378,"journal":{"name":"Biomaterial investigations in dentistry","volume":" ","pages":"152-159"},"PeriodicalIF":0.0,"publicationDate":"2021-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8530498/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39555572","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of cementation techniques on fracture load of monolithic zirconia crowns.","authors":"Janne Angen Indergård,&nbsp;Anneli Skjold,&nbsp;Christian Schriwer,&nbsp;Marit Øilo","doi":"10.1080/26415275.2021.1990764","DOIUrl":"https://doi.org/10.1080/26415275.2021.1990764","url":null,"abstract":"<p><strong>Aim: </strong>The aim of this study was to evaluate the effect of cement on the fracture load of monolithic zirconia crowns with different yttria content (3 and 5 mol%).</p><p><strong>Methods: </strong>A total of 62 monolithic zirconia crowns, 40 3Y-zirconia crowns (Prettau^® Zirconia, Zirkonzahn) and 22 5Y-zirconia crowns (Prettau^® 4 Anterior^®, Zirkonzahn) were produced to a shallow chamfer molar preparation. The 3Y-crowns were divided into four groups and attached to composite abutment duplicates (SDR^® flow+, Dentsply DeTrey GmbH) using the following four cementation techniques; (1) Self-adhesive resin-based cement, (2) Pre-treatment with air-abrasion and self-adhesive resin-based cement, (3) Zinc phosphate cement, (4) Glass-ionomer cement. The 5Y-crowns were divided into two groups and attached to the duplicates with; (1) Self-adhesive resin-based cement, or (2) Air-abrasion pre-treatment and self-adhesive resin-based cement. All crowns were loaded axially (0.5 mm/min) on the occlusal surface until fracture occurred.</p><p><strong>Results: </strong>Among the 3Y-zirconia groups, the zinc phosphate cement group fractured at lower loads compared to the resin-based cement groups, with and without air-abrasion, (<i>p</i> < .012). Among the 5Y-groups the air-abraded crowns fractured at statistically significant lower loads compared to the untreated crowns (<i>p</i> < .028). Load at fracture values were significantly different between the two zirconia materials (<i>p</i> < .001), with fracture loads ranging from 3873 to 7500 N in the 3Y-groups, and 2100 to 4948 N in the 5Y-groups.</p><p><strong>Conclusions: </strong>Resin-based cementation increased the fracture load compared to non-adhesive cementation. The 3Y-crowns fractured at almost twice the loads of the 5Y-crowns. Pre-treatment with air abrasion reduced the strength of the 5Y-crowns only, showing the importance of differentiating the treatment of the two materials.</p>","PeriodicalId":72378,"journal":{"name":"Biomaterial investigations in dentistry","volume":" ","pages":"160-169"},"PeriodicalIF":0.0,"publicationDate":"2021-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8530494/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39555574","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effect of light curing intensity on bulk-fill composite resins: heat generation and chemomechanical properties.","authors":"Wendy Jingwen Wang,&nbsp;Anastasiia Grymak,&nbsp;John Neil Waddell,&nbsp;Joanne Jung Eun Choi","doi":"10.1080/26415275.2021.1979981","DOIUrl":"https://doi.org/10.1080/26415275.2021.1979981","url":null,"abstract":"<p><strong>Objectives: </strong>The aim of this study was to assess the effect of light curing intensity and wavelength spectrum on heat generation and chemomechanical properties of bulk-fill composites.</p><p><strong>Methods: </strong>Four bulk-fill restorative materials (Filtek bulk-fill, Tetric PowerFill bulk-fill, Beautifil Bulk restorative and Admira Fusion X-tra were used in this study. A total of 100 cylindrical specimens of each composite (<i>n</i> = 25/group) were prepared, then cured using monowave light curing unit (LCU) with a single light intensity of 1470 mW/cm², and polywave LCU with three different light intensities (1200,2100, 3050mW/cm²). The temperature change during polymerisation was measured by five K-type thermocouples placed in each 1 mm layer from top to bottom. Hardness and degree of conversion of composites at each level were evaluated. Results were statistically analysed.</p><p><strong>Results: </strong>The use of polywave LCU resulted in statistically higher peak temperatures ranging between 31.4-63.5 °C compared to the temperature generated by monowave LCU ranging between 29.5-60 °C (<i>p</i> < .05). Curing using polywave LCU with the highest light intensity of 3050 mW/cm² caused the highest peak temperature irrespective of the composite types. There was no significant difference in hardness with different light curing intensities and curing times, regardless of the bulk-fill resin materials (<i>p</i> > .05). A positive correlation was also found between the hardness and the DoC of the four bulk-fill composites.</p><p><strong>Conclusion: </strong>The change in temperature during polymerisation of bulk-fill composites were found to be proportional to the increase in light curing intensity. Mechanical properties of the bulk-fill composites were dependent on the composition and the type of photoinitiators.</p>","PeriodicalId":72378,"journal":{"name":"Biomaterial investigations in dentistry","volume":" ","pages":"137-151"},"PeriodicalIF":0.0,"publicationDate":"2021-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8491722/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39521033","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bond strength of zirconia- or polymer-based copings cemented on implant-supported titanium bases - an <i>in vitro</i> study.","authors":"Eliann Oddbratt,&nbsp;Lisa Hua,&nbsp;Bruno R Chrcanovic,&nbsp;Evaggelia Papia","doi":"10.1080/26415275.2021.1974301","DOIUrl":"https://doi.org/10.1080/26415275.2021.1974301","url":null,"abstract":"<p><strong>Purpose: </strong>To evaluate the bond strength between polymer-based copings and zirconia copings as positive control, cemented on implant-supported titanium bases with different adhesive cement systems. Moreover, to evaluate if airborne-particle abrasion of polymethylmetacrylate (PMMA) would enhance the bond strength.</p><p><strong>Methods: </strong>Four groups of different materials were used to fabricate the copings, 30 in each group: airborne-particle abraded milled zirconia (TAZirconia, control group), milled PMMA (TPMMA), airborne-particle abraded milled PMMA (TAPMMA) and 3 D-printed micro filled hybrid resin (TAMFH). Each group of copings was cemented on titanium bases by three different adhesive cement systems, 10 each: Multilink Hybrid Abutment, Panavia V5, RelyX Ultimate. The specimens were stored dry at room temperature for 24 h, subjected to thermocycling for 5000 cycles followed by evaluating the bond strength by tensile strength test.</p><p><strong>Results: </strong>TPMMA and TAPMMA cemented with Multilink Hybrid Abutment showed statistically significant lower bond strength in comparison to TAZirconia and TAMFH. No difference was observed between the latter two. TPMMA, TAPMMA and TAMFH had a statistically significant lower bond strength compared to the control group when cemented with Panavia V5. TPMMA and TAPMMA cemented with Rely X Ultimate showed statistically significant lower bond strength in comparison to the control group.</p><p><strong>Conclusion: </strong>Almost all experimental groups, except 3 D-printed MFH, performed inferior than the positive control group where the highest bond strength was reported for the cementation of zirconia copings cemented with Panavia V5 or Rely X Ultimate. Airborne-particle abrasion did not improve the bond strength of the PMMA, except when Multilink Hybrid Abutment was used.</p>","PeriodicalId":72378,"journal":{"name":"Biomaterial investigations in dentistry","volume":" ","pages":"129-136"},"PeriodicalIF":0.0,"publicationDate":"2021-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8439223/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39424895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Inner marginal strength of CAD/CAM materials is not affected by machining protocol.","authors":"Julia Lubauer,&nbsp;Renan Belli,&nbsp;Fernanda H Schünemann,&nbsp;Ragai E Matta,&nbsp;Manfred Wichmann,&nbsp;Sandro Wartzack,&nbsp;Harald Völkl,&nbsp;Anselm Petschelt,&nbsp;Ulrich Lohbauer","doi":"10.1080/26415275.2021.1964969","DOIUrl":"https://doi.org/10.1080/26415275.2021.1964969","url":null,"abstract":"<p><strong>Purpose: </strong>Here we aimed to compare two machining strategies regarding the marginal strength of CAD/CAM materials using a hoop-strength test in model sphero-cylindrical dental crowns, coupled with finite element analysis.</p><p><strong>Materials and methods: </strong>Five CAD/CAM materials indicated for single posterior crowns were selected, including a lithium disilicate (IPS e.max^® CAD), a lithium (di)silicate (Suprinity^® PC), a polymer-infiltrated ceramic scaffold (Enamic^®), and two indirect resin composites (Grandio^® Blocs and Lava™ Ultimate). A sphero-cylindrical model crown was built on CAD Software onto a geometrical abutment and machined using a Cerec MC XL system according to the two available protocols: <i>rough-fast</i> and <i>fine-slow</i>. Specimens were fractured using a novel hoop-strength test and analyzed using the finite element method to obtain the inner marginal strength. Data were evaluated using Weibull statistics.</p><p><strong>Results: </strong>Machining strategy did not affect the marginal strength of any restorative material tested here. Ceramic materials showed a higher density of chippings in the outer margin, but this did not reduce inner marginal strength. IPS e.max^® CAD showed the statistically highest marginal strength, and Enamic^® and Lava™ Ultimate were the lowest. Grandio^® Blocs showed higher performance than Suprinity^® PC.</p><p><strong>Conclusions: </strong>The <i>rough-fast</i> machining strategy available in Cerec MC XL does not degrade the marginal strength of the evaluated CAD/CAD materials when compared to its <i>fine-fast</i> machining strategy. Depending on the material, resin composites have the potential to perform better than some glass-ceramic materials.</p>","PeriodicalId":72378,"journal":{"name":"Biomaterial investigations in dentistry","volume":" ","pages":"119-128"},"PeriodicalIF":0.0,"publicationDate":"2021-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8386733/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39358954","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Monowave and polywave light-curing of bulk-fill resin composites: degree of conversion and marginal adaptation following thermomechanical aging.","authors":"Sheila Celia Mondragón Contreras,&nbsp;Ana Luiza Barbosa Jurema,&nbsp;Evaniele Santos Claudino,&nbsp;Eduardo Bresciani,&nbsp;Taciana Marco Ferraz Caneppele","doi":"10.1080/26415275.2021.1937181","DOIUrl":"https://doi.org/10.1080/26415275.2021.1937181","url":null,"abstract":"<p><p><i>Aim:</i> This study aimed to evaluate the effect of polymerization with either a monowave (MW) or a polywave (PW) light-curing unit (LCU) on the degree of conversion (DC) and marginal adaptation following thermomechanical aging of an ormocer bulk-fill resin composite (RC) (Admira fusion X-tra Bulk Fill - AB), a methacrylate-based bulk-fill RC (Tetric N-Ceram Bulk Fill - TB) and a conventional RC (Tetric N-Ceram - TC). <i>Methods:</i> DC was assessed in five samples of each RC using Fourier transform infrared spectroscopy. For determination of marginal adaptation, standard preparations were made in 60 bovine incisors, divided into three groups, according to the RC. The bulk-fill RC was inserted in a single increment of 4 mm. In contrast, the conventional RC was inserted in three increments. Marginal gap was evaluated after thermomechanical aging. Data were analyzed using a two-way analysis of variance (ANOVA) and Tukey's tests for multiple comparisons (<i>α</i> = 0.05). <i>Results:</i> The two-way ANOVA showed a significant effect (<i>p</i><.05) of the RC factor but not of the LCU factor. The Tukey test showed that TB had the significantly lowest DC followed by TC, and with AB having the significantly highest DC. For the marginal adaptation, a significant effect was found for the LCU factor and the for the interaction RC × LCU (<i>p</i><.05). Groups light-cured with PW showed significantly wider marginal gaps than MW. TC presented wider marginal gaps (17.36 µm) when cured with PW than when cured with MW (13.05 µm). The two bulk-fill RC resulted in similar marginal gap formation to each other. <i>Conclusion:</i> The ormocer-based bulk-fill RC showed a higher DC than the methacrylate-based bulk-fill RC but similar marginal adaptation. The LCU, MW or PW, had no significant influence on the DC, and no relevance on the marginal adaptation.</p>","PeriodicalId":72378,"journal":{"name":"Biomaterial investigations in dentistry","volume":" ","pages":"72-78"},"PeriodicalIF":0.0,"publicationDate":"2021-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/26415275.2021.1937181","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39291814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fracture resistance of resin based and lithium disilicate endocrowns. Which is better? - A systematic review of <i>in-vitro</i> studies.","authors":"Joshna Beji Vijayakumar,&nbsp;Preethi Varadan,&nbsp;Lakshmi Balaji,&nbsp;Mathan Rajan,&nbsp;Rajeswari Kalaiselvam,&nbsp;Sindhu Saeralaathan,&nbsp;Arathi Ganesh","doi":"10.1080/26415275.2021.1932510","DOIUrl":"https://doi.org/10.1080/26415275.2021.1932510","url":null,"abstract":"<p><p><b>Objectives:</b> The primary objective of this systematic review is to compare the fracture resistance of lithium disilicate (LDS)-based endocrowns and resin-based (RB) endocrowns of in-vitro studies, and the secondary objective is to compare their catastrophic failures. <b>Materials and Methods:</b> The review protocol was registered in the P ROSP ERO database (CRD42020166201). A comprehensive literature search was done in PubMed, Cochrane, EBSCOhost and Google Scholar using key terms. Only in-vitro studies that compared fracture resistance of LDS-based endocrowns and indirect RB endocrowns in molars were included. Data extraction, risk of bias assessment and qualitative analysis of the included studies were performed. <b>Results:</b> Five studies were included in this systematic review. The overall risk of bias for the included studies was moderate. Under axial loading, RB endocrowns showed similar fracture resistance when compared with LDS endocrowns. However, they showed better fracture resistance when compared with zirconia reinforced lithium silicate (ZLS) endocrowns. Furthermore, RB endocrowns showed fewer catastrophic failures than LDS-based endocrowns. <b>Conclusions:</b> RB endocrowns have similar or better fracture resistance and fewer catastrophic failures when compared to LDS-based endocrowns.</p>","PeriodicalId":72378,"journal":{"name":"Biomaterial investigations in dentistry","volume":" ","pages":"104-111"},"PeriodicalIF":0.0,"publicationDate":"2021-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/26415275.2021.1932510","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39291815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of different tooth preparation and bonding techniques on the fracture resistance of tooth fragment reattachment.","authors":"Shaymaa M Nagi,&nbsp;Sherif M Khadr","doi":"10.1080/26415275.2021.1952873","DOIUrl":"https://doi.org/10.1080/26415275.2021.1952873","url":null,"abstract":"<p><strong>Purpose: </strong>comparing the influence of different tooth preparation and bonding techniques on the fracture resistance of tooth fragment reattachment.</p><p><strong>Materials and method: </strong>Ninety bovine central incisors were selected. Fifteen teeth act as a control (Group A). Experimental specimens were sectioned at the mesial-incisal proximal edge 3 mm from the incisal edge in a labio-lingual direction at 25degree inclination apically. Experimental specimens were then divided into five groups according to the tooth reattachment techniques utilized; Group B: no tooth preparation + Cured bond + Flowable composite; Group C: no tooth preparation + Uncured bond + Flowable composite; Group D: Bevel + bond + Flowable composite; Group E: Over-contouring + bond + Nanohybrid composite; Group F: Over-contouring + bond + Flowable composite. Specimens were subjected to thermocycling between 5 °C and 55 °C for 500 cycles with 30 sec. dwell time. Fracture strength was evaluated using universal testing machine. Data was analyzed using One-way ANOVA.</p><p><strong>Results: </strong>There was a statistically significant difference between Group A and all the experimental groups, <i>p</i> < .001. Group E showed the highest statistically significant fracture resistance mean value compared to other experimental groups, while the lowest mean value was found in Group B.</p><p><strong>Conclusion: </strong>Though, none of the tested techniques resulted in fracture resistance similar to that of intact teeth, over-contouring technique with nanohybrid composite application showed better performances compared to the other techniques tested in the current study. Bonding plus flowable resin composite application with no additional tooth preparation and placement of a bevel are not suggested due to the low fracture strength achieved.</p>","PeriodicalId":72378,"journal":{"name":"Biomaterial investigations in dentistry","volume":" ","pages":"112-118"},"PeriodicalIF":0.0,"publicationDate":"2021-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/26415275.2021.1952873","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39276530","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Marginal and internal fit of crowns based on additive or subtractive manufacturing.","authors":"Yasser Haddadi,&nbsp;Bahram Ranjkesh,&nbsp;Flemming Isidor,&nbsp;Golnosh Bahrami","doi":"10.1080/26415275.2021.1938576","DOIUrl":"10.1080/26415275.2021.1938576","url":null,"abstract":"<p><strong>Objective: </strong>To assess the marginal and internal fit of crowns manufactured by additive and subtractive manufacturing technique.</p><p><strong>Materials and methods: </strong>Twenty extracted teeth prepared for complete coverage crowns were scanned with an intra-oral scanner (Omnicam, DentsplySirona). For the subtractive manufacturing (SM) group, ten crowns were manufactured in a hybrid resin block (Vita Enamic, Vita Zahnfabrik). For the additive manufacturing (AM) group, the crowns were manufactured in a hybrid resin material (NextDent C&B, 3D systems). The design parameters were identical for the two groups. The marginal and internal fit (determined at the axial wall, the cusp tip and occlusally) was assessed before cementation with the replica technique and after cementation under stereomicroscope after sectioning of the crowned teeth.</p><p><strong>Results: </strong>For the SM group, the marginal fit was 91 µm (±28 µm) before cementation and 85 µm (±18 µm) after cementation. In the AM group, the marginal fit was 75 µm (±29 µm) before cementation and 71 µm (±18 µm) after cementation. The differences were not statistically significant. As regards the internal fit, the fit at the axial wall was statistically significantly better in the SM group than in the AM group (<i>p</i>=.009 before cementation and .03 after cementation). Occlusally the fit in the AM group was significantly better than in the SM group after cementation (<i>p</i><.001).</p><p><strong>Conclusion: </strong>Within the limitations of the current study, the marginal fit of additively manufactured crowns is comparable to crowns manufactured with chair-side subtractive technique and within the clinically acceptable range. As regards the internal fit no one technique was consistently superior.</p>","PeriodicalId":72378,"journal":{"name":"Biomaterial investigations in dentistry","volume":" ","pages":"87-91"},"PeriodicalIF":0.0,"publicationDate":"2021-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/26415275.2021.1938576","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39166630","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A three-year randomized clinical trial evaluating direct posterior composite restorations placed with three self-etch adhesives.","authors":"Joseph Sabbagh,&nbsp;Layal El Masri,&nbsp;Jean Claude Fahd,&nbsp;Paul Nahas","doi":"10.1080/26415275.2021.1939034","DOIUrl":"https://doi.org/10.1080/26415275.2021.1939034","url":null,"abstract":"<p><strong>Aim: </strong>To compare the clinical performance of composite restorations placed with a universal adhesive, one-step and two-step self-etch adhesives in class I and II posterior cavities.</p><p><strong>Materials and methods: </strong>In this <i>in vivo</i> study, 46 volunteers presenting with at least three carious lesions were included. Each participant received the three restorative systems: universal adhesive/nanofilled composite (Scotchbond Universal/Filtek Z350 XT: SBU/FZXT), one-step self-etch adhesive/microhybrid composite (G-aenial bond/G-aenial Posterior: GB/GP) and the two-step self-etch adhesive/nanohybrid composite (OptiBond XTR/Herculite Ultra: OBX/HU). The adhesives were all placed in self-etch mode. In total, 138 restorations were evaluated at baseline and at 6,12 and 36 months using the modified United States Public Health Service criteria. Data were analysed using Kruskal-Wallis, Mann-Whitney U, Friedman and Wilcoxon non-parametric tests (<i>p</i> < .05). Ninety-one restorations were evaluated at 36 months.</p><p><strong>Results: </strong>Seven restorations, three SBU/FZXT, three GB/GP and one OBX/HU failed during this study. The reasons for failure were marginal fracture and secondary caries. SBU/FZXT restorations showed significant marginal deterioration in all parameters. Overall success rates were: 93.5% (SBU/FZXT), 96.6% (GB/GP) and 96.8% (OBX/HU).</p><p><strong>Conclusions: </strong>After three years, the three restorative systems have comparable clinical effectiveness and success rates, except for the marginal integrity, that was suboptimal for both the SBU/FZXT and GB/GP restorations in comparison to the OBX/HU restorations.</p>","PeriodicalId":72378,"journal":{"name":"Biomaterial investigations in dentistry","volume":" ","pages":"92-103"},"PeriodicalIF":0.0,"publicationDate":"2021-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/26415275.2021.1939034","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39166631","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}