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1.
Sameh Attia Jörg Wiltfang Philipp Streckbein Jan-Falco Wilbrand Thaqif El Khassawna Katharina Mausbach Hans-Peter Howaldt Heidrun Schaaf 《Journal of cranio-maxillo-facial surgery》2019,47(5):786-791
Purpose
Microvascular fibula flap surgery is a reliable and effective procedure for reconstructing the jaws after tumour surgery. This procedure allows the placement of dental implants after bone consolidation. This study was designed to evaluate the oral, functional, and aesthetic rehabilitation of tumour patients with immediate fibula transfer and dental implants and included assessment of diet, speech, and aesthetics.Materials and methods
The study included 34 patients who underwent ablative tumour surgery and immediate jaw reconstruction using a fibula free flap with consecutive rehabilitation by dental implants. In total, 134 implants were inserted into the transferred fibula. The functional and aesthetic results were assessed using a questionnaire. Implant loss and oral excursion were compared with diet type, speech ability, functionality, and patient satisfaction.Results
Of the 34 patients included in this study, 33 completed the questionnaire. Twenty-six patients (76%) could eat normally without the limitation of a hard or soft diet, 73% could speak intelligibly, and 31 rated the aesthetic result from good to excellent.Conclusion
The fibula flap with the early application of endosseous implants allowed primary immediate reconstruction of the jaw, significantly leading to functional and aesthetic satisfaction in patients who underwent ablative tumour surgery. 相似文献2.
Guillermo de la Rosa Castolo Sonia V. Guevara Perez Pierre-Jean Arnoux Laurent Badih Franck Bonnet Michel Behr 《The Journal of prosthetic dentistry》2019,121(3):546.e1-546.e10
Statement of problem
Implant-supported overdentures (IODs) are a treatment option for patients with complete edentulism. However, this treatment increases the possibilities of peri-implant complications, characterized by inflammation or partial loss of surrounding hard and soft tissues.Purpose
The purpose of this finite element analysis study was to evaluate the mechanical performance of different bar-IOD designs under different clinical configurations by comparing the stress and strain distribution on the bone during secondary stabilization.Material and methods
A finite element model of the mandible representing a patient with complete edentulism was developed. Different designs of bar-IODs were modeled and compared. The parameters studied were the material properties (cobalt-chromium, zirconium dioxide, titanium grade 5, and titanium grade 4), diameter and bar-IOD cross-sectional shape, tilt of the posterior implants (30 degrees), presence of a distal extension cantilever in the bar-IODs (12 mm), and number of implants (4 or 6). Two different mastication loading conditions were analyzed. One- and 2-way ANOVAs and the Tukey honestly significant differences post hoc test (α=.05) were used to determine the significant von Mises stress and strain values in the bone.Results
The 4 materials tested in the bar-IOD did not have a significant mechanical effect on the bone (P<.05). A smaller diameter and structure of the bar-IOD led to significantly higher bone stress (P<.001). A distal extension cantilever led to an increased stress concentration (model M1 versus model M3: P<.001), which reached 50% in the event of tilting of the posterior implants (model M2 versus model M4: P<.001). Tilting of the posterior implants alone, without extension, had a nonsignificant effect (model M3 versus model M4: P=.999). Model M5 supported with 6 implants reduces the stress transferred to the bone compared with model M3 supported with 4 implants (P<.05).Conclusions
Distal extensions in bar-IODs, the tilt of the posterior implants, and the low amount of material in the cross-sectional area in the bar-IOD were the most influential parameters on the mechanical resistance of dental implants in the mandibular bone. 相似文献3.
Marcelo Coelho Goiato Henrique Rinaldi Matheus Rodrigo Antonio de Medeiros Daniela Micheline dos Santos Sandro Basso Bitencourt Aldiéris Alves Pesqueira 《The Journal of prosthetic dentistry》2017,117(5):685-689
Statement of problem
The rehabilitation of patients after a maxillectomy involves the use of an obturator to seal oral-nasal-sinus communication and to facilitate mastication, swallowing, and speech.Purpose
The purpose of this in vitro study was to evaluate different attachment systems used for implant-retained obturators at dissipation loads and under shear forces.Material and methods
Photoelastic models were fabricated with 3 external hexagon implants at the incisor, canine, and first molar regions. Subsequently, overdentures were made, and metal hooks were placed at the incisor and first molar regions to displace the prostheses in the vertical, anterior, and posterior directions, with a constant speed of 50 mm/min. A photoelastic model with an O-ring or bar-clip system was placed in a circular polariscope, and tested with a universal testing machine. The images were recorded and high-intensity fringes were counted using software. For strain gauge analysis, each strain gauge was placed horizontally at the mesial and distal sides of the implants. The registered strains were submitted to 2-way ANOVA (α=.05).Results
The O-ring showed the lowest number of high-intensity fringes in photoelastic imaging, while the strain gauge analysis showed the lowest stress values in the bar-clip group (P=.007).Conclusions
The stress around titanium implant necks was more damaging to surrounding bone, while the bar-clip attachment system had a better biomechanical performance. The bar-clip presented the lowest strain values around the dental implants and few high-intensity fringes. 相似文献4.
Björn Gjelvold Deyar Jallal Hadi Mahmood Ann Wennerberg 《The Journal of prosthetic dentistry》2019,121(3):498-503
Statement of problem
Different factors influence the degree of deviation in dental implant position after computed tomography–guided surgery. The surgical guide–manufacturing process with desktop 3D printers is such a factor, but its accuracy has not been fully evaluated.Purpose
The purpose of this in vitro study was to evaluate the deviation in final dental implant position after the use of surgical guides fabricated from 2 different desktop 3D printers using a digital workflow.Material and methods
Twenty 3D-printed resin models were prepared with missing maxillary premolar. After preoperative planning, 10 surgical guides were produced with a stereolithography printer and 10 with a digital light-processing (DLP) printer. A guided surgery was performed; 20 dental implants (3.8×12 mm) were installed, and a digital scan of the dental implants was made. Deviations between the planned and final position of the dental implants were evaluated for both the groups.Results
A statistically significant difference between stereolithography and DLP were found for deviation at entry point (P=.023) and the vertical implant position (P=.009). Overall lower deviations were found for the guides from the DLP printer, with the exception of deviation in horizontal implant position.Conclusions
The tested desktop 3D printers were able to produce surgical guides with similar deviations with regard to the final dental implant position, but the DLP printer proved more accurate concerning deviations at entry point and vertical implant position. 相似文献5.
Carlo Maiorana Pier Paolo Poli Anna Mascellaro Susanna Ferrario Mario Beretta 《Journal of cranio-maxillo-facial surgery》2019,47(5):805-814
Purpose
To evaluate the long-term outcome of dental implants placed with a staged procedure in resorbed alveolar ridges reconstructed with iliac crest autogenous onlay grafts.Materials and methods
All consecutive patients treated with iliac crest onlay bone grafts and dental implants were retrospectively evaluated. During the appointment, clinical and radiological examinations were conducted to assess implant survival. A survived implant was defined as an implant still stable and in function at the follow-up visit. Implant survival was estimated at the implant level using Kaplan-Meier analyses. The cumulative survival rate was estimated using a life-table analysis. Subgroup analyses were performed for age, position, and type of retention using the log-rank test. A p-value of <0.05 was considered statistically significant.Results
The cohort consisted of 21 female subjects receiving a total of 140 rough-surface titanium implants. Of them, 128 survived and 12 failed, yielding a cumulative survival rate of 91.1% over a median survival time of 312 months. Implants supporting cement-retained prostheses exhibithed lower survival rate compared to screw-retained restorations (p = 0.001).Conclusion
Implants placed in bone augmented with iliac crest onlay grafts showed high long-term survival rates. Cement-retained restorations were more prone to develop implant failures. 相似文献6.
Statement of problem
The long-term color stability of precolored monolithic zirconia has not been thoroughly investigated.Purpose
The purpose of this in vitro study was to evaluate the effect of hydrothermal aging on the optical properties, phase transformation, and surface topography of precolored monolithic zirconia ceramics.Material and methods
Precolored monolithic zirconia specimens (17.0×17.0×1.5 mm, n=50) and lithium disilicate glass-ceramic specimens (16.0×16.0×1.5 mm, n=50) were artificially aged in an autoclave at 134°C under 0.2 MPa for 0, 1, 3, 5, or 10 hours (n=10). CIELab color parameters were obtained from spectral measurements. The translucency parameter (TP) and CIEDE2000 color differences (ΔE00) were calculated. The microstructural and surface properties were analyzed by X-ray diffraction (XRD), atomic force microscope (AFM), and scanning electron microscope (SEM). Data were analyzed with 2-way ANOVA and pairwise comparison (α=.05).Results
Significant interactions were found between aging time and ceramic material on L*, a*, b*, and TP (P<.001) as follows: b* partial eta squared [ηp2]=0.689; L* ηp2=0.186; a* ηp2=0.176; and TP ηp2=0.137. The b* values significantly decreased after aging for zirconia (P<.001), whereas TP increased after aging for zirconia (P<.014) except at 10 hours (P=.389) and for lithium disilicate (P<.001). The ΔE00 values relative to baseline ranged from 2.03 to 2.52 for aged zirconia and from 0.07 to 0.23 for aged lithium disilicate. XRD analysis revealed that hydrothermal aging promoted an increase in m-phase contents. AFM and SEM demonstrated surface alterations after aging.Conclusions
Optical properties and microstructures of precolored monolithic zirconia ceramics were affected by hydrothermal aging, and translucency increased slightly with aging time. 相似文献7.
Statement of problem
The introduction of intraoral scanners has increased the use of digital technology in dental procedures. However, research on the extent of clinically recommended scans is lacking.Purpose
The purpose of this in vitro study was to compare 3D arch distortion according to the distance from the tooth at the beginning of a complete-arch scan made using an intraoral scanner.Material and methods
An industrial scanner was used to digitize a master model for a computer-aided design (CAD) reference model. In addition, the master model was digitized using 4 intraoral scanners (TRIOS2, TRIOS3, CS3500, and CS3600) and 1 dental laboratory scanner (FREEDOM HD) to make the CAD test model (N=20). The scanned teeth were divided using an inspection software program (Geomagic control X), and overlapping and 3D analyses of the CAD reference model and CAD test model were performed. The presence or absence of normal distribution in the root mean square (RMS) values of all divided teeth was assessed and evaluated with the Kruskal-Wallis test (α=.05), and post hoc comparison was performed using the Mann-Whitney U-test and Bonferroni correction method (α=.005).Results
The overall RMS value was significantly different for all scanners (P<.001). The dental laboratory scanner showed the lowest value (47.5 ±1.6 μm), whereas TRIOS2 showed the highest value (343.4 ±56.4 μm). TRIOS3 (9.6 ±1.2 μm) showed the best trueness in those teeth where the scan started. However, the larger the scan range, the lower the RMS value difference between TRIOS3 and CS3500. The RMS values of the dental laboratory scanners were higher than those of the intraoral scanners in the narrow scan range. CS3600 showed an RMS value less than or equal to that of the dental laboratory scanner at 5 teeth scan ranges. However, the wider the scan range, the lower the RMS values of all the intraoral scanners.Conclusions
Current complete-arch scanning is not sufficiently accurate for fabricating fixed prostheses. However, intraoral scanners are useful for short scans, such as those for single (TRIOS2, TRIOS3, and CS3500) or short-span prostheses (CS3600). 相似文献8.
Majed Al-Akhali Matthias Kern Adham Elsayed Abdulaziz Samran Mohamed Sad Chaar 《The Journal of prosthetic dentistry》2019,121(4):644-650
Statement of problem
With the development of new computer-aided design and computer-aided manufacturing (CAD-CAM) restorative dental materials, limited data regarding their survival rate and fracture strength are available when they are used as occlusal veneers. Therefore, these materials should be evaluated under conditions similar to those of the oral environment before being recommended for clinical use.Purpose
To evaluate the influence of thermomechanical fatigue loading on the fracture strength of minimally invasive occlusal veneer restorations fabricated from different CAD-CAM materials and bonded to human maxillary premolars using self-etchnig bonding technique.Material and methods
Sixty-four CAD-CAM occlusal veneer restorations were fabricated from group LD (lithium disilicate [e.max CAD]), LS (zirconia-reinforced lithium silicate [Vita Suprinity]), PI (polymer-infiltrated ceramic [Vita Enamic]), and PM (polymethylmethacrylate [Telio CAD]). The occlusal veneers were luted to enamel (n=16) using a self-etching primer (Multilink Primer A/B) and a luting composite resin (Multilink Automix). Half of the specimens of each group (n=8) were randomly selected and subjected to thermomechanical fatigue loading in a masticatory simulator (1.2 million cycles at 98 N with 5°C-55°C thermocycling). All specimens were quasistatically loaded until fracture. The statistical analysis was made using the Kruskal-Wallis and Mann-Whitney U tests (α=.05).Results
According to the Kaplan-Meier analysis after the thermomechanical fatigue of the 4 groups, the cumulative survival rate was as follows: group LD, 50% group LS, 62.5% group PI, 37.5%; and group PM, 50%. Although some of the surviving specimens exhibited microcracking, their integrity or bonding to teeth was not affected. Thermomechanical fatigue significantly reduced the fracture strength of group PI (P=.047) and group PM (P=.025). Without thermomechanical fatigue, group PM showed significantly higher fracture strength than group LS (P=.015).Conclusions
In general, thermomechanical fatigue decreased the survival rate and fracture strength in all test groups. 相似文献9.
Kaidiliya Yalikun Manabu Kanazawa Mariko Tanoue Shunsuke Minakuchi 《The Journal of prosthetic dentistry》2019,121(3):492-497
Statement of problem
Single-implant–retained mandibular overdentures (1-IODs) may be an alternative to 2-IOD for maladaptive denture patients giving comparable satisfaction, lower cost, and shorter treatment times. However, studies evaluating the effect of the number of implants on the strain exerted around the implants of IODs using strain-gauge analysis are lacking.Purpose
The purpose of this in vitro study was to evaluate the effect of the number of implants on the strain in an IOD under various loading and dislodging conditions.Material and methods
A mandibular IOD with the Locator attachment system (pink nylon inserts) was fabricated on artificial mucosa. Three implant positions recorded the loading: 1-IOD (mid-anterior), 2-IOD (bilateral lateral incisor), and 3-IOD (mid-anterior and bilateral canine) were prepared. Strain gauges attached to the mid-anterior implant replica for the 1-IOD, the left lateral incisor replica for the 2-IOD, and the anterior and left canine replicas for the 3-IOD. Vertical loads of 50 N were applied to the experimental overdenture in the mid-anterior and right molar and left molar regions. Three dislodging tests were performed in 3 different areas: mid-anterior, posterior, and mid-anterior and bilateral molar. Six measurements were made under each loading and dislodging condition for each IOD (N=6). During the calibration test, the resultant strain measured by strain gauge was converted into a lateral force (F) value by using linear regression: Fanterior-posterior(N)=1.08×strain (με), Fposterior-anterior(N)=0.192×strain (με), Fleft-right(N)=0.590×strain (με), Fright-left(N)=0.560×strain (με). Statistical analysis was performed by using 1-way ANOVA and the Tukey honestly significant difference test (α=.05).Results
The 3-IOD demonstrated the significantly highest strain under loading and dislodging conditions (P<.05). The 1-IOD demonstrated the significantly highest strain during right-side loading (P<.05). Upon anterior and left-side loading, no significant difference was noted in strain between the 1-IOD and 2-IOD (P=.413, P=.272). Under dislodging conditions, the 1-IOD exhibited the significantly lowest strain (P<.05).Conclusions
Within the limitations of this study, the 3-IOD demonstrated the highest lateral resistance force during load and dislodge testing, whereas the 1-IOD exhibited the lowest. 相似文献10.
Fabián Murillo-Gómez Mario Fernando De Goes 《The Journal of prosthetic dentistry》2019,121(4):713.e1-713.e8
Statement of problem
Glass-ceramic materials are typically treated with hydrofluoric acid (HF) and silane to improve their bond to composite resin; however, HF may be harmful to human tissues and the integrity of the material, and its application is a technique-sensitive procedure. A novel self-etching ceramic primer has been introduced with the claim that it can solve those problems. However, independent scientific evidence regarding its performance is scarce.Purpose
The purpose of this in vitro study was to evaluate the effect of self-etching silane primer on glass-ceramic surface roughness and on long-term bonding between glass-ceramic and composite resin cement.Material and methods
Plates of 3 materials (n=10), lithium disilicate glass-ceramic (LDC) (IPS e.max CAD), leucite-based glass-ceramic (LEU) (IPS Empress CAD), and resin-modified ceramic (PIC) (VITA ENAMIC), were treated in the following ways: no treatment (C), HF (5%) applied during the recommended time for each material (HF), and self-etching ceramic primer (Monobond Etch & Prime [MBEP]). Surface roughness (Sa) was analyzed with a laser 3D profiler. Ceramic sticks were subjected to (n=20) no treatment (C); treatment with hydrofluoric acid plus silane (HF+S); and treatment with self-etching ceramic primer (MBEP) bonded to prepolymerized composite resin sticks with composite resin cement (Variolink II) and stored for 24 hours and 1 year (n=10). The assemblies were submitted to microtensile bond strength testing (μTBS). Data were analyzed using ANOVA and the Tukey pairwise, post hoc test (α=.05). Failure pattern and surface and interface morphology were assessed using scanning electron microscopy.Results
Only individual factors resulted in statistically significant differences for both variables (material: P<.001; surface treatment: P=.020), interaction (P=.570). HF group (0.49 ±0.11 μm) showed statistically higher roughness values (P≤.05) than control groups (0.44 ±0.97 μm), while MBEP (0.48 ±0.11 μm) was comparable with both. HF produced greater surface alterations than MBEP and C. PIC (0.60 ±0.051 μm) exhibited significantly higher roughness values (P≤.05) than LDC (0.37 ±0.07 μm) and LEU (0.45 ±0.04). Regarding μTBS, the general mean of PIC (24.6 ±10.1 MPa) was higher (P≤.05) than LEUs (14.7 ±6.7 MPa) and LDCs (13.1 ±4.8 MPa), while treatment groups HF+S (17.9 ±10.0 MPa) and MBEP (20.5 ±9.7 MPa) produced higher μTBS values than control groups (14.2 ±5.5 MPa). Adhesive failure was associated with low μTBS values and aged specimens, while cohesive failure within the composite resin-cement layer and mixed failures were associated with higher μTBS values. Interface debonding was detected in C groups for LDC and LEU. PIC exhibited better interface stability.Conclusions
MBEP produced smoother surfaces than HF. HF+S and MBEP significantly improved ceramic and composite resin cement bonding. 相似文献11.
Anna Gabriella Camacho Presotto Cláudia Lopes Brilhante Bhering Marcelo Ferraz Mesquita Valentim Adelino Ricardo Barão 《The Journal of prosthetic dentistry》2017,117(3):373-379
Statement of problem
Several studies have shown the superiority of computer-assisted design and computer-assisted manufacturing (CAD-CAM) technology compared with conventional casting. However, an advanced technology exists for casting procedures (the overcasting technique), which may serve as an acceptable and affordable alternative to CAD-CAM technology for fabricating 3-unit implant-supported fixed dental prostheses (FDPs).Purpose
The purpose of this in vitro study was to evaluate, using quantitative photoelastic analysis, the effect of the prosthetic framework fabrication method (CAD-CAM and overcasting) on the marginal fit and stress transmitted to implants. The correlation between marginal fit and stress was also investigated.Material and methods
Three-unit implant-supported FDP frameworks were made using the CAD-CAM (n=10) and overcasting (n=10) methods. The frameworks were waxed to simulate a mandibular first premolar (PM region) to first molar (M region) FDP using overcast mini-abutment cylinders. The wax patterns were overcast (overcast experimental group) or scanned to obtain the frameworks (CAD-CAM control group). All frameworks were fabricated from cobalt-chromium (CoCr) alloy. The marginal fit was analyzed according to the single-screw test protocol, obtaining an average value for each region (M and PM) and each framework. The frameworks were tightened for the photoelastic model with standardized 10-Ncm torque. Stress was measured by quantitative photoelastic analysis. The results were submitted to the Student t test, 2-way ANOVA, and Pearson correlation test (α=.05).Results
The framework fabrication method (FM) and evaluation site (ES; M and PM regions) did not affect the marginal fit values (P=.559 for FM and P=.065 for ES) and stress (P=.685 for FM and P=.468 for ES) in the implant-supported system. Positive correlations between marginal fit and stress were observed (CAD-CAM: r=0.922; P<.001; overcast: r=0.908; P<.001).Conclusions
CAD-CAM and overcasting methods present similar marginal fit and stress values for 3-unit FDP frameworks. The decreased marginal fit of frameworks induces greater stress in the implant-supported system. 相似文献12.
Nicole Kalberer Albert Mehl Martin Schimmel Frauke Müller Murali Srinivasan 《The Journal of prosthetic dentistry》2019,121(4):637-643
Statement of problem
Complete dentures fabricated by computer-aided design and computer-aided manufacturing (CAD-CAM) techniques have become popular. The 2 principal CAD-CAM techniques, milling and rapid prototyping (3D printing), used in the fabrication of complete dentures have been reported to yield clinically acceptable results. However, clinical trials or in vitro studies that evaluated the accuracy of the 2 manufacturing techniques are lacking.Purpose
The purpose of this in vitro study was to compare the differences in trueness between the CAD-CAM milled and 3D-printed complete dentures.Material and methods
Two groups of identical maxillary complete dentures were fabricated. A 3D-printed denture group (3DPD) (n=10) and a milled denture group (MDG) (n=10) from a reference maxillary edentulous model. The intaglio surfaces of the fabricated complete dentures were scanned at baseline using a laboratory scanner. The complete dentures were then immersed in an artificial saliva solution for a period of 21 days, followed by a second scan (after immersion in saliva). A third scan (after the wet-dry cycle) was then made after 21 days, during which the complete dentures were maintained in the artificial saliva solution during the day and stored dry at night. A purpose-built 3D comparison software program was used to analyze the differences in the trueness of the complete dentures. The analyses were performed for the entire intaglio surface and specific regions of interest: posterior crest, palatal vault, posterior palatal seal area, tuberosity, anterior ridge, vestibular flange, and mid-palatal raphae. Independent t tests, ANOVA, and post hoc tests were used for statistical analyses (α=.05).Results
The trueness of the milled prostheses was significantly better than that of the rapid prototyping group with regard to the entire intaglio surface (P<.001), posterior crest (P<.001), palatal vault (P<.001), posterior palatal seal area (P<.001), tuberosity (P<.001), anterior ridge (baseline: P<.001; after immersion in saliva: P=.001; after the wet-dry cycle: P=.011), vestibular flange (P<.001), and mid-palatal raphae (P<.001).Conclusions
The CAD-CAM, milled complete dentures, under the present manufacturing standards, were superior to the rapidly prototyped complete dentures in terms of trueness of the intaglio surfaces. However, further research is needed on the biomechanical, clinical, and patient-centered outcome measures to determine the true superiority of one technique over the other with regard to fabricating complete dentures by CAD-CAM techniques. 相似文献13.
Shajidan Kelimu Mariko Hattori Shataer Awuti Mahmoud E. Elbashti Yuka I. Sumita Hisashi Taniguchi 《The Journal of prosthetic dentistry》2019,121(4):671-675
Statement of problem
A palatogram aids prosthodontists and speech pathologists in evaluating the precise prosthetic treatment needed and the effectiveness of such treatment to improve speech intelligibility. Powder is commonly used to visualize tongue-palate contact, where wetted areas of powder in the oral cavity reveal such contact during palatography. However, discomfort and the risk of aspiration are among the shortcomings of this method, and an improved method is needed.Purpose
The purpose of this in vitro study was to examine the feasibility of a new method of palatography that uses airborne-particle–abraded acrylic resin so that wet areas can be easily distinguished from dry areas.Material and methods
Seventy-two specimens of heat-polymerized acrylic resin were prepared in 6 different resin colors. After the specimens had been airborne-particle abraded, CIELab color values for each specimen were measured using a colorimeter under dry and wet conditions and recorded. Color difference (ΔE) was then computed, and a paired Student t test, 1-way analysis of variance, and multiple comparison using the Tukey post hoc analysis were applied (α=.05).Results
A significant color difference was found between the 2 conditions in all acrylic resin specimens examined. Mean ΔE ranged from 5.58 to 6.76.Conclusions
The results indicated that an airborne-particle–abraded acrylic resin surface can show color differences made by wetting on palatograms. 相似文献14.
Sereen Kattan Su-Min Lee Elliot V. Hersh Bekir Karabucak 《Journal of the American Dental Association (1939)》2019,150(3):165-177
Background
The authors conducted a systematic review that addresses the following population, intervention, comparison, outcome question: “In adults requiring dental therapy with pulpally involved teeth, what is the comparative efficacy of buffered local anesthetics (LAs) compared with that of nonbuffered LAs in achieving anesthetic success?”Types of Studies Reviewed
The authors searched MEDLINE, Scopus, Cochrane Library, ClinicalTrials.gov, World Health Organization International Trials Registry Platform, OpenGrey, Google Scholar Beta, and 2 textbooks to identify double-blinded randomized controlled trials in which researchers directly compared the efficacy of buffered and nonbuffered LAs in adult participants, as well as any associated side effects. Furthermore, they checked the reference lists of all included and excluded studies to identify any further trials. Weighted anesthesia success rates were estimated and compared by using a random-effects model.Results
A total of 14,011 studies were initially identified from the search; 5 double-blinded randomized clinical trials met inclusion criteria. Buffered LAs were more likely to achieve successful anesthesia than nonbuffered LAs (odds ratio, 2.29; 95% confidence interval, 1.11 to 4.71; P = .0232; I2 = 66%).Conclusions and Practical Implications
This investigation revealed that buffered LAs are more effective than nonbuffered LAs when used for mandibular or maxillary anesthesia in pulpally involved teeth. Buffering of LAs has 2.29 times greater likelihood of achieving successful anesthesia. 相似文献15.
Alex Leo Sequeira Aparna I. Narayan Vinu Thomas George 《The Journal of prosthetic dentistry》2019,121(5):843-847
Statement of problem
Variation in the baseline mechanical properties of polyamide thermoplastic polymers used in the fabrication of prosthetic dental appliances and the effects of nonaldehyde disinfectants on the mechanical properties of these polymers are unclear.Purpose
The purpose of this in vitro study was to compare the flexural and impact strengths of 2 flexible denture materials (Valplast and Sunflex) and evaluate the effect of 24-hour immersion in nonaldehyde disinfectant (Perform) on their flexural and impact strengths.Material and methods
Of 48 specimens of Valplast and Sunflex, half were immersed in nonaldehyde disinfectant solution containing the active ingredient 2% peroxymonosulfate for 24 hours. Flexural and impact strengths were measured using a universal testing machine. The Student t test with Bonferroni correction was used (α=.008).Results
For the Valplast group, the mean ±standard deviation flexural strength was 27.8 ±0.57 MPa, and the impact strength was 3.5 ±0.98 kJ/m2. For the Sunflex group, the mean flexural strength was 57.4 ±4.09 MPa, and the impact strength was 6.0 ±3.11 kJ/m2. Sunflex showed greater flexural strength (P≤.001) and impact strength (P=.001) than Valplast. A significant increase in the impact strength (P≤.001) but not in the flexural strength of Valplast was observed after exposure to the disinfectant solution. Immersion disinfection had no significant effect on the strength of Sunflex.Conclusions
The flexural and impact strengths of Sunflex were significantly greater than those of Valplast. Immersion disinfection with peroxymonosulfate had no significant effect on Sunflex but increased the impact strength of Valplast. 相似文献16.
Daniel A. Decurcio Giampiero Rossi-Fedele Carlos Estrela Shaju J. Pulikkotil Venkateshbabu Nagendrababu 《Journal of endodontics》2019,45(4):387-393.e2
Introduction
This systematic review and meta-analysis aimed to assess whether machine-assisted agitation resulted in less postoperative pain (PP) compared with syringe irrigation with needle alone in adult patients undergoing root canal treatment.Methods
A literature search was performed in 3 electronic databases for articles published before August 2018. Randomized clinical trials published in English that compared PP between machine-assisted agitation and syringe irrigation with needles as part of nonsurgical root canal treatment were included. Two authors were independently involved in the article selection process, data extraction, and assessment of the quality of included studies using the revised Cochrane risk of bias tool. The pooled effect estimates of the standardized mean difference (SMD) between machine-assisted agitation and syringe irrigation with needle was calculated by a random effects–modeled meta-analysis. A subgroup meta-analysis was performed. The quality of evidence was evaluated by the Grading of Recommendations, Assessment, Development and Evaluations approach.Results
Six studies were included for systematic review. Meta-analysis was performed using 3 studies and showed that machine-assisted agitation resulted in less PP compared with syringe irrigation with needle at 24 hours (SMD = ?0.73; 95% confidence interval, ?1.04 to ?0.42; I2 = 30.6%) and 48 hours (SMD = ?0.60; 95% CI, ?0.85 to ?0.35; I2 = 0%). The quality of evidence by Grading of Recommendations, Assessment, Development and Evaluations for the PP outcomes (24 hours and 48 hours) was graded as “moderate” quality.Conclusions
Machine-assisted agitation reduced PP compared with syringe irrigation with needles in nonsurgical root canal treatment. Future clinical trials are needed to support the result of this review. 相似文献17.
Edmundo Marques do Nascimento-Júnior Gustavo Marques Sobral dos Santos Mário Luis Tavares Mendes Maximiliano Cenci Marcos Britto Correa Tatiana Pereira-Cenci Paulo Ricardo Saquete Martins-Filho 《Journal of the American Dental Association (1939)》2019,150(4):269-277.e1
Background
The aim of this systematic review and meta-analysis was to evaluate the efficacy of cryotherapy in reducing pain, trismus, and facial swelling in patients undergoing third-molar surgery.Types of Studies Reviewed
The authors searched for randomized clinical trials in PubMed, Web of Science, SCOPUS, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, Google Scholar, and OpenThesis. Eligibility criteria were population: patients submitted to removal of impacted third molars; intervention and comparison: postoperative cryotherapy versus no cold therapy; and outcomes: primary outcome was postoperative pain, and secondary outcomes were facial swelling and trismus. Eligible studies must have reported at least 1 of the outcomes of interest. After extracting data and assessing quality, the authors performed the meta-analyses.Results
The authors included 6 studies in the quantitative synthesis analysis. Differences in pain intensity were found on postoperative day 2 (weighted mean difference, ?0.72; 95% confidence interval, ?1.45 to 0.01; P = .05) and postoperative day 3 (weighted mean difference, ?0.36; 95% confidence interval, ?0.59 to ?0.13; P = .002). No evidence was found that cryotherapy was effective in reducing trismus and facial swelling. The quality of evidence was graded as low.Conclusions and Practical Implications
Evidence suggests that cryotherapy may have a small benefit in reducing pain after third-molar surgery, but it is not effective on facial swelling and trismus. Owing to the lack of standardization of cold application, effective evidence-based treatment protocols for cryotherapy after third-molar surgery still need to be established. 相似文献18.
Thomas Connert Ralf Krug Florin Eggmann Isabel Emsermann Ashraf ElAyouti Roland Weiger Sebastian Kühl Gabriel Krastl 《Journal of endodontics》2019,45(3):327-331
Introduction
The aim of this in vitro study was to compare endodontic access cavities in teeth with calcified root canals prepared with the conventional technique and a guided endodontics approach regarding the detection of root canals, substance loss, and treatment duration.Methods
Six identical sets of upper and lower jaw models were produced with 3-dimensional–printed incisors that had simulated calcified root canals. Splints for guided access preparations were fabricated based on 3-dimensional surface scans and cone-beam computed tomographic data sets. Under simulated clinical conditions, 3 operators with different levels of experience prepared access cavities on each front tooth with the conventional technique and guided endodontics (8 teeth per technique and operator). Access cavities were volumetrically assessed on postoperative cone-beam computed tomographic scans. Statistical significance was tested by examining the overlap of 95% confidence intervals (CIs).Results
Canal location was successful in 10 of 24 cases (41.7%) using the conventional technique and 22 of 24 cases (91.7%) with the guided approach. The mean substance loss of the conventional access and the guided access was 49.9 mm3 (95% CI, 42.2–57.6 mm3) and 9.8 mm3 (95% CI, 6.8–12.9 mm3), respectively. The treatment lasted 21.8 minutes (95% CI, 15.9–27.7 minutes) for the conventional technique and 11.3 minutes (95% CI, 6.7–15.9 minutes) for guided endodontics. The success of the guided approach was not influenced by the experience of the operator.Conclusions
Guided endodontics allows a more predictable and expeditious location and negotiation of calcified root canals with significantly less substance loss. 相似文献19.
Alexandre Barboza Elias Renata Antoun Simão Maíra Prado Paulo Francisco Cesar Glauco Botelho dos Santos Eduardo Moreira da Silva 《The Journal of prosthetic dentistry》2019,121(3):485-491
Statement of problem
Nonthermal argon plasma may increase the surface energy of yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) dental ceramics. However, studies that evaluated the effect of increased plasma treatment times on the bond strength of resin cements to Y-TZP ceramics are lacking.Purpose
The purpose of this in vitro study was to evaluate the effect of different nonthermal argon plasma (NTAP) treatment times on the surface energy and bond strength of a self-adhesive resin cement to Y-TZP ceramic.Material and methods
Forty-eighty Y-TZP plates were divided into 2 groups (n=24): as-sintered (AS) and airborne-particle abrasion (APA) with 50-μm Al2O3, which were subdivided into 4 groups (n=6) according to the time of NTAP treatment: 0, 20, 60, and 120 seconds. The surface energy was evaluated with a goniometer. Forty Y-TZP blocks submitted to the same surface treatments (8 groups; n=5) were cemented to composite resin blocks, using a self-adhesive resin cement. After storage in distilled water at 37°C for 24 hours, the Y-TZP-composite resin blocks were cut into beams and submitted to a microtensile bond strength (μTBS) test. Data were analyzed using 2-way ANOVA and the Tukey honestly significant differences test (α=.05).Results
Treatment with NTAP increased the surface energy for AS and APA groups (P<.05). For both groups, the μTBS was as follows: 0 seconds < 20 seconds < 60 seconds = 120 seconds (P<.05). Only after 120 seconds of NTAP treatment was the μTBS of APA higher than that of AS (P<.05).Conclusions
Treatment with NTAP improved the surface energy and increased the μTBS of self-adhesive resin cement to Y-TZP ceramic, with higher times of plasma treatment resulting in higher bond strength. 相似文献20.
Goran I. Benic Irena Sailer Marco Zeltner Janine N. Gütermann Mutlu Özcan Sven Mühlemann 《The Journal of prosthetic dentistry》2019,121(3):426-431