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1.
Maki Hosoki Keisuke Nishigawa Toyoko Tajima Mayu Ueda Yoshizo Matsuka 《Journal of prosthodontic research》2018,62(4):426-431
Purpose
Studies have reported cases of metal allergy caused by titanium-containing materials. We wished to clarify the relationship between titanium allergy and dental implants by describing patients who suffered allergic symptoms after they had received such implants.Methods
A total of 270 patients who visited a Dental Metal Allergy Clinic at Tokushima University Hospital from April 2010 to March 2014 were the study cohort. Patch testing with 28 types of metal allergens (including four titanium allergens) was undertaken for patients.Results
A total of 217 patients (80.4 %) exhibited allergy-positive reactions to at least one type of metal allergen. Mercury, palladium, chromium and nickel exhibited a higher prevalence of allergy-positive reactions than other metals. Sixteen patients visited our clinic suffering allergic symptoms after receiving dental implants. Eleven of those patients exhibited allergy-positive reactions for any of the metal allergens, and 4 of these patients had allergy-positive reactions against titanium allergens. The total number of allergy-positive reactions for titanium allergens among all 270 patients was 17 (6.3 %). No patient exhibited a positive reaction only for the titanium allergen.Conclusions
The prevalence of allergy-positive reactions for titanium allergens was lower than for other metal allergens. We suggest examination of pre-implant patients who have a history of hypersensitivity reactions to metals. 相似文献2.
Akinari Inui Ryohei Itou Toshirou Oyama Yoshihiro Tamura Kosei Kubota Wataru Kobayashi 《Oral Science International》2017,14(2):37-39
Aims
To compare the clinical characteristics of sialolithiasis between pediatric and adult patients.Settings and Design
Subject characteristics, clinical manifestations, salivary calculi characteristics, and treatment modalities and outcomes from medical records were retrospectively compared between pediatric and adult patients with sialolithiasis visiting the Department of Oral and Maxillofacial Surgery, Hirosaki University Hospital, between 2005 and 2014.Subjects
We included 5 pediatric (all boys) and 45 adult (20 men; 25 women) patients.Results
Most patients had submandibular swelling. The calculi were located on the right in 100.0% of pediatric patients and 57.8% of adult patients. Moreover, 20.0% of pediatric patients and 35.6% of adult patients exhibited sialoliths in the glands. Calculi were <5 mm in size in 100.0% of pediatric patients and 33.3% of adult patients. Pediatric sialolithiasis treatment included intraoral retrieval under local anesthesia in 4 cases (80.0%) and spontaneous expulsion from the duct in 1 case (20.0%). Adult sialolithiasis treatment included gland resection under general anesthesia in 8 cases (17.8%), intraoral retrieval under general anesthesia in 6 cases (13.3%), intraoral retrieval under local anesthesia in 19 cases (42.2%), spontaneous expulsion in 6 cases (13.3%), and follow-up only in 6 cases (13.3%).Conclusions
A large number of relatively small and distal sialoliths in pediatric patients was removed using intraoral retrieval under local anesthesia. This difference in the choice of treatment between pediatric and adult sialolithiasis may be attributed to the size and palpability of the calculi. 相似文献3.
Pooyan Makvandi Rezvan Jamaledin Mostafa Jabbari Nasser Nikfarjam Assunta Borzacchiello 《Dental materials》2018,34(6):851-867
Objective
Quaternary ammonium compounds (QACs) represent one of the most effective classes of disinfectant agents in dental materials and resin nanocomposites. This reviews aims to give a wide overview on the research in the field of antibacterial QACs in dental materials and nanocomposites.Method
An introduction to dental materials components as well as the microorganisms and methods of evaluation for the antimicrobial assays are presented. Then, the properties and synthesis route of QACs, as monomer and filler, are shown. Finally, antimicrobial monomers and fillers, specifically those contain quaternary ammonium salts (QASs), in dental materials are reviewed.Results
QACs have been used as monomer and micro/nanofiller in restorative dentistry. They possess one or more methacrylate functional groups to participate in polymerization reactions. QACs with multiple methacrylate groups can also be used as crosslinking agents. Furthermore, QACs with chain length from ～12 to 16 have higher antimicrobial activity in cured dental resins. In general, increasing the chain length leads to a threshold value (critical point) and then it causes decrease in the antimicrobial activity.Significance
The current state of the art of dental materials and resin nanocomposites includes a wide variety of antimicrobial materials. Among them, QACs presents low cytotoxicity and excellent long-term antimicrobial activity without leaching out over time. 相似文献4.
Tomas Duminis Saroash Shahid Natalia G. Karpukhina Robert G. Hill 《Dental materials》2018,34(5):e83-e88
Objective
Dental restoration aesthetics, particularly the translucency of modern dental restorative filling materials depends on the refractive index (RI) match between the different components in the material. In the case of dental composites (DC), the RI of the polymer must match the RI of the filler otherwise the material is optically opaque and has limited depth of cure. In the case of glass ionomer cements (GICs), the RI of the ion-leachable glass must match the RI of the polysalts to engineer a smart material with a tooth-like appearance. The RI of oxide glasses can be calculated by means of Appen factors. However, no Appen factors are available for the fluoride components in dental glasses. Therefore, the objective of this study is to empirically derive composition-specific Appen factors for the metal fluorides in complex multicomponent glasses for use in dentistry.Methods
Two series of bioactive glasses and two series of ionomer-type glasses were produced for this study. Refractive indices of all glasses were then measured by the Becke Line technique. Thereafter, composition-specific factors for the metal fluorides were derived.Results
It was found that increasing metal fluoride content reduces the RI of multicomponent dental glasses linearly. A series-specific Appen factors for the metal fluorides were successfully derived and allow RI calculation to within 0.005.Significance
This paper proposes a modified Appen Model with composition-specific Appen factors for the metal fluorides for the development of dental restoratives with enhanced aesthetics and improved depth of cure of dental composites. 相似文献5.
Objective
Clinical studies should be one main aspect underlying dentists’ decision-making towards dental materials. Study design, conduct, analysis and reporting impact on the usefulness of studies. We discuss problems with current studies and highlight areas where improvement might be possible.Methods
Based on systematically and non-systematically collected data, we demonstrate where and why current studies in clinical dentistry deliver less-than-optimal results. Lending from general medicine, we suggest ways forward for clinical dental material science.Results
Randomized controlled (efficacy) trials remain a major pillar in dental material science, as they reduce selection bias and, if well-designed and conducted, have high internal validity. Given their costs and limited external validity, alternatives like practice-based or pragmatic controlled trials or observational studies can complement the evidence-base. Prior to conduct, researchers should focus on study comparators and setting (answering questions with relevance to clinical dentistry), and pay attention to statistical power, considering the study aim (superiority or non-inferiority trial), the expected event rate, and attrition. Study outcomes should be chosen on the basis of a core outcome set or, if not available, involving patients and other stakeholders. Studies should be registered a priori, and reporting should adhere to standards. Possible clustering should be accounted for during statistical analysis.Significance
Many clinical studies in dental material science are underpowered, and of limited validity and usefulness for daily decision-making. Dental researchers should mirror existing efforts in other medical fields in making clinical studies more valid and applicable, thus contributing to better dental care. 相似文献6.
Mariela Machado Christine Wallace Bruce Austin Suhas Deshpande Agnes Lai Terry Whittle Iven Klineberg 《Journal of prosthodontic research》2018,62(4):473-478
Purpose
This study has evaluated the pre and post perceptions of patients with ectodermal dysplasia (ED) who have been referred to Westmead Centre for Oral Health for treatment with dental implants.Methods
Six patients with ED and hypodontia were treated with new maxillary complete dental prostheses or fixed implant prostheses, and a mandibular fixed dental prosthesis with implants. Patient perceptions were recorded with a 10 cm visual analogue scale (VAS). All patients were asked to draw a line on the VAS which best described their feelings regarding aesthetics, chewing, diet and speech.Results
Improvement in aesthetics was reported for all patients with change scores ranging from +9 to +4 points. Similarly, all patients reported an improvement in chewing ability with +6 point changes in 2 patients, and +8, +3, +7 and +1 in the other 4 patients. Five out of 6 patients reported less dietary restriction with 3 patients each indicating a change of +6 points, +4 points, +3 points, and 2 patients reporting +1 point change. Speech improved by +1 point for 3 patients, whilst 1 patient improved by +6 points, a further 2 patients scored no change.Conclusions
Patients with ED treated with dental implants reported encouraging outcomes post treatment after prostheses were fitted. Follow-up from 1.6 to 6.8 years has confirmed these improvements. 相似文献7.
8.
Dental restorations made from alloys corrode during their service time. In cases of suspected toxic or allergic reactions to the corrosion products, the composition of the intraoral dental restorations has to be determined. The sample materials can be obtained intra-orally in a non-destructive manner using the chipping test. Metallic shavings are extracted with the aid of a dental stone and graphite carrier platelet, which is then transferred to an electron microscope for electro dispersive X-ray (EDX) analysis. The chipping test suffers from a rather complicated and error-prone procedure of obtaining and transferring the samples.
Objective
The objective of the present study was the validation of a simplified method for non-destructive in-situ extraction of dental alloy samples, using a newly developed dental bur made from carbon fiber reinforced polyether ether ketone (PEEK), which at the same time serves as an electrically conductive sample carrier for EDX analysis.Methods
Fifteen burs for dental hand pieces were manufactured from carbon fiber reinforced PEEK, using two formulations. The burs were passed over precious and non-precious dental alloys with different rotation speeds. The alloy samples embedded in the burs were analyzed using EDX and compared to a control.Results
The burs manufactured from PEEK containing 30% short carbon fibers proved sufficiently robust for sample extraction even from the harder non-precious metals. The results of EDX analysis were in accordance with the control,no statistical significant differences, free of contamination, and were not affected by rotation speed,higher as 20%.Significance
The proposed method is valid, practical and constitutes an improvement over the traditional chipping test. 相似文献9.
Mariano S. Pedano Xin Li Shuchen Li Zeyi Sun Stevan M. Cokic Eveline Putzeys Kumiko Yoshihara Yashuhiro Yoshida Zhi Chen Kirsten Van Landuyt Bart Van Meerbeek 《Dental materials》2018,34(5):797-808
Objectives
To evaluate the effect of the eluates from 3 freshly-mixed and setting hydraulic calcium-silicate cements (hCSCs) on human dental pulp cells (HDPCs) and to examine the effect of a newly developed hCSC containing phosphopullulan (PPL) on HDPCs.Methods
Human dental pulp cells, previously characterized as mesenchymal stem cells, were used. To collect the eluates, disks occupying the whole surface of a 12-well plate were prepared using an experimental hCSC containing phosphopullulan (GC), Nex-Cem MTA (GC), Biodentine (Septodont) or a zinc-oxide (ZnO) eugenol cement (material-related negative control). Immediately after preparing the disks (non-set), 3 ml of Dulbecco's Modified Eagle Medium (DMEM) with 10% fetal bovine serum (FBS) were added. The medium was left in contact with the disks for 24 h before being collected. Four different dilutions were prepared (100%, 50%, 25% and 10%) and cell-cytotoxicity, cell-proliferation, cell-migration and odontogenic differentiation were tested. The cell-cytotoxicity and cell-proliferation assays were performed by XTT-colorimetric assay at different time points. The cell-migration ability was tested with the wound-healing assay and the odontogenic differentiation capacity of hCSCs on HDPCs was tested with RT-PCR.Results
Considering all experimental data together, the eluates from 3 freshly-mixed and setting hCSCs appeared not cytotoxic toward HDPCs. Moreover, all three cements stimulated proliferation, migration and odontogenic differentiation of HDPCs.Significance
The use of freshly-mixed and setting hCSCs is an appropriate approach to test the effect of the materials on human dental pulp cells. The experimental material containing PPL is non-cytotoxic and positively stimulates HDPCs. 相似文献10.
Purpose
Fiber-reinforced composite (FRC) fixed dental prostheses (FDPs) have shown good performance in clinical applications due to their good mechanical properties and minimally invasive approach. However, typical failure patterns of FRC FDPs are often localized at the pontic site. That reflects the structural considerations at the framework and pontic location that need to be examined when creating these kinds of prostheses.Study selection
Peer-reviewed articles and other scientific literature were reviewed for providing up-to-date information on how pontics of FRC FDPs can be made. A thorough literature search was done using PubMed and Google Scholar. Two individuals did an assessment of the articles in order to include those related to pontics and framework design of FRC FDPs. The search terms used were “fiber-reinforced dental prosthesis” and “Pontics of fiber-reinforced dental prosthesis”.Results
These findings indicate that a cross-sectional fiber design, substructure and thicker pontics made of a variety of materials might reduce failures at the pontic site.Conclusions
The thickness of pontics of FRC FDPs interrelated with the vertical positioning of the FRC framework influences the load-bearing capacities of prostheses of these kinds. The understanding of the factors involved in the fabrication of pontics of FRC FDPs may overcome the drawbacks identified in these prostheses, thus extending their longevity. 相似文献11.
Purpose
To compare treatment effects of Class II elastics and anterior mandibular position training against fixed Class II corrector (PowerScope?) during the correction of skeletal Class II malocclusion with fixed appliance in growing patients.Materials and methods
Thirty-six growing patients with skeletal Class II malocclusion with a retruded pogonion position were randomly allocated to the Class II elastics or PowerScope? groups. Preadjusted edgewise fixed appliances were used in both treatment groups. Skeletal, dental and profile changes were compared using lateral cephalograms taken before (T0), after initial alignment (T1) and after Class I obtained (T2) for 16/18 patients in the Class II elastics group and 15/18 patients in the PowerScope? group.Results
The duration of treatment was significantly longer for the Class II elastics group than PowerScope? group. In terms of skeletal changes, Class II elastics increased mandibular length, midfacial length and mandibular plane angle significantly more than the PowerScope?. In terms of dental changes, Class II elastics increased dental height significantly more than the PowerScope?.Conclusions
Both treatment modalities reduced severity of Class II malocclusion and decreased profile convexity. Class II elastics with anterior mandibular position training increased mandibular length more but required longer treatment duration. The PowerScope? had a greater effect on maxillary dento-alveolar restriction. (ClinicalTrials.in.th: TCTR 20180220003). 相似文献12.
13.
Stefano Pieralli Ralf-Joachim Kohal Emilia Lopez Hernandez Sam Doerken Benedikt Christopher Spies 《Dental materials》2018,34(2):171-182
Objective
To determine the osseointegration rate of zirconium dioxide (ZrO2) dental implants in preclinical investigations.Data
Data on the osseointegration rate was extracted considering the bone to implant contact (BIC), removal torque analysis (RTQ) and push-in tests. Meta analyses were conducted using multilevel multivariable mixed-effects linear regression models. The ?idák method was used in case of multiple testing.Sources
An electronic screening of the literature (MEDLINE/Pubmed, Cochrane Library and Embase) and a supplementary manual search were performed. Animal investigations with a minimum sample size of 3 units evaluating implants made of zirconia (ZrO2) or its composites (ZrO2 > 50 vol.%) were included.Study selection
The search provided 4577 articles, and finally 54 investigations were included and analyzed. Fifty-two studies included implants made from zirconia, 4 zirconia composite implants and 37 titanium implants. In total, 3435 implants were installed in 954 animals.Conclusions
No significant influence of the evaluated bulk materials on the outcomes of interest could be detected. When comparing different animal models, significant differences for the evaluated variables could be found. These results might be of interest for the design of further animal investigations. 相似文献14.
Elham Azad Mohammad Atai Mojgan Zandi Parvin Shokrollahi Laleh Solhi 《Dental materials》2018,34(9):1263-1270
Objectives
This is a confirmatory study to evaluate the effect of photoinitiator type and concentration, matrix monomer chemical structure, and nanoparticle incorporation on the physical and mechanical properties of an experimental dentin bonding agent.Materials and methods
Different concentrations of camphorquinone-amine (CQ-A) system, butanedione (BD), and phenylpropanedione (PPD), as photoinitiator, BTDMA, as a comonomer containing carboxylic acid groups, and silica nanoparticles as reinforcing inorganic filler were incorporated into a methacrylate base experimental dental adhesive. The effect of these ingredients, as independent variables, on the shrinkage kinetics, flexural strength and modulus, and microshear bond strength of the adhesives were then investigated. The results were analyzed using one-way ANOVA and Tukey’s post-hoc test at the significance level of 0.05.Results
The results indicate that the efficiency of CQ-A initiator system is diminished in the presence of the acidic monomer BTDMA while the photopolymerization is efficiently progressed with BD as initiator. PPD shows the lowest efficiency in the photopolymerization of the adhesives. BTDMA as a monomer with the capability of interaction with tooth structure provides adhesive with improved microshear bond strength to dentin. Incorporation of silica nanoparticles at low concentrations enhances the flexural and microshear strength of the dentin bonding agent.Significance
Understanding the structure–property relationship in dental adhesives may help the material selection in clinical dentistry. The study elucidates the relationship between monomer structure, initiator type, and nanofiller and physical and mechanical properties in dental adhesives. 相似文献15.
Luca Boschini 《Giornale Italiano di Endodonzia》2018,32(2):76-79
Aim
As dental trauma is an unpredictable event, the patient is sometimes unable to receive dental care immediately in case of tooth fracture complicated by exposure to the pulp. It is conceivable that a long wait may favor bacterial contamination that can lead to necrosis of the pulp. The aim of this paper is to present a clinical case in which the pulp has been protected domiciliary to reduce post-traumatic hypersensitivity and the risk of pulpal necrosis.Materials and methods
In the presented clinical case, the nail polish was used as an emergency material for the direct capping of the pulp of two fractured incisors. In this way it was possible to protect the pulp and seal the dentinal tubules for 5 days, such it is the time between trauma and therapy.Results
The application of the nail polish led to a reduction in hypersensitivity; at 2-year follow-up both teeth were still vital.Conclusions
Based on this experience, it is suggested the possibility to recommend the use of nail polish as a protective material for the pulp and for reducing symptoms in case of complicated and uncomplicated fractures, if the dentist is consulted by telephone and the patient is not in condition to reach it quickly. 相似文献16.
Anuradha Prakki Yaoyang Xiong Janaína Bortolatto Lucélia Lemes Gonçalves Arwa Bafail Greg Anderson Alexander Terry Stavroullakis 《Dental materials》2018,34(11):1625-1633
Objectives
We investigated the biostability of dentin organic matrices treated with epigallocatechin gallate (EGCG) in comparison to chlorhexidine (CHX), both extracted from functionalized copolymers.Methods
Copolymers were prepared with bis-GMA:TEGDMA and incorporated with 1% of EGCG or CHX (w/w). Blank copolymers were used as control. Copolymer samples were individually stored in 1 mL deionized water to produce copolymer extracts. Dentin matrices were obtained by demineralization of dentin disks in 10% phosphoric acid solution. Matrices were individually treated with 1 mL of the copolymer extracts or distilled water for 48 h. Collected extracts were analyzed by high-performance liquid chromatography (HPLC) for the presence and quantification of EGCG, CHX, and copolymer by-products. Treated dentin matrices were tested for ultimate tensile strength, gravimetric changes, and swelling ratio. The treatment media were tested for total protein concentration, and dentin protease activity through solubilized telopeptide (ICTP- and CTX-ELISA) assays. The treatment media were also submitted to proteomic analysis.Results
HPLC identified released unreacted copolymer species and showed higher release of CHX compared to EGCG from respective copolymer extracts. EGCG extract inhibited activity of dentin proteolytic enzymes and promoted collagen biomodification observed by the telopeptide assays and in the changes to dentin matrix properties. The proteomic results showed less collagenous peptide hits in the EGCG extract media compared to CHX, and suggest compound-specific dentin protein binding interactions.Significance
This study demonstrates specific antiproteolytic effect and protein interactions of EGCG copolymer extract directly on dentin. This represents an advancement in dental materials which can impact the clinical procedures. 相似文献17.
Background
Promising results of initial clinical trials with yttria-stabilized zirconia have led to more extensive use of zirconia in dental implant superstructures. The applications have extended to abutments and complex individually designed crown-abutment one-piece structures. Little is known about their clinical success and the primary cause of failures.Purpose
The aim of this study was to identify the cause of fracture of retrieved implant-retained one-piece prostheses that failed during clinical use.Methods
Nine fractured restorations were analyzed with fractographic methods and their fracture origins were identified.Results
All but two of the fractures originated in an area of tight contact between the implant or titanium screw and the abutment base. Results of the evaluation showed that zirconia-based implant restorations with very thin walls in the region connecting the prosthesis to the implant are vulnerable to damage from the screw retaining process and fracture from non-axial loads. Two restorations failed due to veneer fractures.Significance
The findings suggest that large crowns on narrow implants or implants with internal fixation should preferably not be made with zirconia abutments, or that a new design approach should be considered. 相似文献18.
Katrin Heck Juergen Manhart Reinhard Hickel Christian Diegritz 《Dental materials》2018,34(6):e138-e147
Objective
The objective of this RCT was to compare the 10-year clinical performance of QuiXfil with that of Tetric Ceram in posterior single- or multi-surface cavities.Methods
46 QuiXfil (Xeno III) and 50 Tetric Ceram (Syntac classic) composite restorations were placed in 14 stress bearing class I and 82 class II cavities in first or second molars. Clinical evaluation was performed at baseline and after up to 10 years by using modified US Public Health Service criteria. At the last recall period, 26 QuiXfil and 30 Tetric Ceram restorations in 11 stress bearing class I and 45 class II cavities, were assessed.Results
Ten failed restorations were observed during the follow-up period, four Tetric Ceram restorations failed due to secondary caries (2), tooth fracture (1) and bulk fracture combined with secondary caries (1) whereas six QuiXfil restorations failed due to secondary caries (1), tooth fracture (2), secondary caries combined with restoration fracture (1), restoration fracture (1) and postoperative sensitivity (1). Fisher’s exact test yielded no significant difference between both materials (p = 0.487).Significance
Both materials, bulk fill QuiXfil restorations and Tetric Ceram restorations, showed highly clinical effectiveness during the 10-year follow-up. 相似文献19.
Renan Belli Michael Wendler Dominique de Ligny Maria Rita Cicconi Anselm Petschelt Herwig Peterlik Ulrich Lohbauer 《Dental materials》2017,33(1):84-98
Objective
A deeper understanding of the mechanical behavior of dental restorative materials requires an insight into the materials elastic constants and microstructure. Here we aim to use complementary methodologies to thoroughly characterize chairside CAD/CAM materials and discuss the benefits and limitations of different analytical strategies.Methods
Eight commercial CAM/CAM materials, ranging from polycrystalline zirconia (e.max ZirCAD, Ivoclar-Vivadent), reinforced glasses (Vitablocs Mark II, VITA; Empress CAD, Ivoclar-Vivadent) and glass-ceramics (e.max CAD, Ivoclar-Vivadent; Suprinity, VITA; Celtra Duo, Dentsply) to hybrid materials (Enamic, VITA; Lava Ultimate, 3M ESPE) have been selected. Elastic constants were evaluated using three methods: Resonant Ultrasound Spectroscopy (RUS), Resonant Beam Technique (RBT) and Ultrasonic Pulse-Echo (PE). The microstructures were characterized using Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDX), Raman Spectroscopy and X-ray Diffraction (XRD).Results
Young’s modulus (E), Shear modulus (G), Bulk modulus (B) and Poisson’s ratio (ν) were obtained for each material. E and ν reached values ranging from 10.9 (Lava Ultimate) to 201.4 (e.max ZirCAD) and 0.173 (Empress CAD) to 0.47 (Lava Ultimate), respectively. RUS showed to be the most complex and reliable method, while the PE method the easiest to perform but most unreliable. All dynamic methods have shown limitations in measuring the elastic constants of materials showing high damping behavior (hybrid materials). SEM images, Raman spectra and XRD patterns were made available for each material, showing to be complementary tools in the characterization of their crystal phases.Significance
Here different methodologies are compared for the measurement of elastic constants and microstructural characterization of CAD/CAM restorative materials. The elastic properties and crystal phases of eight materials are herein fully characterized. 相似文献20.
Manabu Kanazawa Maiko Iwaki Toshio Arakida Shunsuke Minakuchi 《Journal of prosthodontic research》2018,62(4):509-513