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Clinical Oral Investigations Jun 2024To investigate the effect of multiple firings on color, translucency, and biaxial flexure strength of Virgilite-containing (LiAlSiO) lithium disilicate glass ceramics of...
OBJECTIVES
To investigate the effect of multiple firings on color, translucency, and biaxial flexure strength of Virgilite-containing (LiAlSiO) lithium disilicate glass ceramics of varying thickness.
MATERIALS AND METHODS
Sixty discs were prepared from Virgilite-containing lithium disilicate blocks. Discs were divided according to thickness (n = 30) into T (0.5 mm) and T (1.0 mm). Each thickness was divided according to the number of firing cycles (n = 10); F (Control group): 1 firing cycle; F: 3 firing cycles, and F: 5 firing cycles. The discs were tested for color change (ΔE) and translucency (TP) using a spectrophotometer. Then, all samples were subjected to biaxial flexure strength testing using a universal testing machine. Data were collected and statistically analyzed (α = 0.5). For chemical analysis, six additional T discs (2 for each firing cycle) were prepared; for each firing cycle one disc was subjected to X-ray diffraction analysis (XRD) and another disc was subjected to Energy dispersive X-ray spectroscopy (EDX) and Scanning electron microscope (SEM).
RESULTS
Repeated firing significantly reduced the translucency of F and F compared to F in T (p < 0.001), while for T only F showed a significant decrease in TP (p < 0.001). For ΔE, a significant increase was recorded with repeated firings (p < 0.05) while a significant decrease resulted in the biaxial flexure strength regardless of thickness.
CONCLUSIONS
Repeated firings had a negative effect on both the optical and mechanical properties of the Virgilite-containing lithium disilicate glass ceramics.
CLINICAL RELEVANCE
Repeated firings should be avoided with Virgilite-containing lithium disilicate ceramics to decrease fracture liability and preserve restoration esthetics.
Topics: Ceramics; Dental Porcelain; Materials Testing; Surface Properties; Flexural Strength; X-Ray Diffraction; Color; Dental Stress Analysis; Spectrophotometry; Microscopy, Electron, Scanning; Hot Temperature
PubMed: 38869624
DOI: 10.1007/s00784-024-05746-8 -
Clinical Oral Investigations Jun 2024The aims of this clinical study were to investigate success rate, vital pulp survival rate, tooth survival rate and patient-reported masticatory ability by evaluating...
OBJECTIVES
The aims of this clinical study were to investigate success rate, vital pulp survival rate, tooth survival rate and patient-reported masticatory ability by evaluating the pain symptoms and signs of the cracked teeth as well as Index of Eating Difficulty (IED) and Oral Health Impact Profile-14 (OHIP-14) questionnaire after cracked teeth were restored with occlusal veneers.
MATERIALS AND METHODS
27 cracked teeth of 24 patients with cold and/or biting pains without spontaneous/nocturnal pains were recruited in this study. The cracked teeth were restored with occlusal veneers fabricated by lithium disilicate ceramic. Cold test and biting test were used to evaluate pain signs. IED and OHIP-14 questionnaire were used to evaluate masticatory ability. FDI criteria was used to evaluate restorations. The paired Wilcoxon test was used to analyze significant differences of detection rate of pain signs, OHIP scores and IED grade before and after restorations. Kaplan-Meier survival curve was used to describe the success rate, vital pulp survival rate, and tooth survival rate.
RESULTS
27 cracked teeth were restored with occlusal veneers with average of 22.4-month follow-up. Two cracked teeth had pulpitis and pain signs of the other cracked teeth completely disappeared. OHIP total scores were significantly reduced after treatment. Scores of 'pain', 'occlusal discomfort', 'uncomfortable to eat', 'diet unsatisfactory' and 'interrupted meals' reduced significantly after treatment. After treatment, IED grades of 25 vital teeth were significantly lower than those before treatment. FDI scores of 25 restorations except for 2 teeth with pulpitis were no greater than 2. The 12 months accumulated pulp survival rate of the cracked teeth was 92.6%. The 12 months accumulated tooth survival rate was 100%. The success rate at the latest recall was 92.6%.
CONCLUSION
Occlusal veneer restorations with success rate of 92.6% and the same pulp survival rate might be an effective restoration for treating the cracked teeth.
CLINICAL RELEVANCE
The occlusal veneer restorations might be an option for treating the cracked teeth when cracks only involve enamel and dentin, not dental pulp.
Topics: Humans; Female; Dental Veneers; Male; Adult; Follow-Up Studies; Cracked Tooth Syndrome; Treatment Outcome; Surveys and Questionnaires; Middle Aged; Pain Measurement; Dental Porcelain; Dental Restoration, Permanent; Mastication
PubMed: 38862733
DOI: 10.1007/s00784-024-05735-x -
BMC Oral Health Jun 2024To investigate the fracture resistance and failure modalities of anterior endocrown restorations fabricated employing diverse ceramic materials, and bonded using various...
OBJECTIVE
To investigate the fracture resistance and failure modalities of anterior endocrown restorations fabricated employing diverse ceramic materials, and bonded using various cementation methodologies.
MATERIALS AND METHODS
Forty maxillary central incisors were divided into two main groups based on the ceramic materials used; GroupI (Zir): zirconia endocrwons (Zolid HT, Ceramill, Amanngirrbach) and GroupII (E-Max): e-max endocrowns (IPS e.max CAD, Ivoclar Vivadent). Both groups were further split into two subgroups depending on the cementation protocols; subgroup IA "ZirMDP": endocowns cemented with MDP primer + MDP resin cement, subgroup IB (ZirNon-MDP): cemented with MDP primer + non-MDP resin cement, subgroup IIA (E-maxMDP): cemented with MDP primer + MDP resin cement, subgroup IIB (E-maxNon-MDP): cemented with MDP primer + non-MDP resin cement. (n = 10/subgroup). Endocrowns were manufactured using CAD/ CAM. Teeth were subjected to 10,000 thermal cycles. The fracture test was performed at 45 with a palatal force direction until the fracture occurred. Test results were recorded in Newton. The failure mode was examined using a stereomicroscope. A One-way ANOVA test was utilized to compare different groups regarding fracture strength values. Tukey`s Post Hoc was utilized for multiple comparisons.
RESULTS
The comparative analysis of fracture strength across the diverse groups yielded non-significant differences, as indicated by a p-value exceeding 0.05. Nonetheless, an observable trend emerged regarding the mode of failure. Specifically, a statistically significant prevalence was noted in fractures localized within the endocrown/tooth complex below the cementoenamel junction (CEJ) across all groups, except for Group IIB, "E-max Non-MDP," where fractures within the endocrown/tooth complex occurred above the CEJ.
CONCLUSIONS
Combining an MDP-based primer with an MDP-based resin cement did not result in a significant effect on the anterior endocrown fracture strength.
CLINICAL RELEVANCE
Regardless of the presence of the MDP monomer in its composition, adhesive resin cement achieved highly successful fracture strength when used with MDP-based ceramic primers. Additionally, ceramic materials exhibiting elastic moduli surpassing those of dentin are discouraged due to their propensity to induce catastrophic fractures within the tooth structure.
Topics: Humans; Cementation; Incisor; In Vitro Techniques; Dental Stress Analysis; Resin Cements; Zirconium; Materials Testing; Crowns; Dental Restoration Failure; Ceramics; Dental Materials; Computer-Aided Design; Dental Porcelain
PubMed: 38851731
DOI: 10.1186/s12903-024-04381-9 -
BMC Oral Health Jun 2024Effects of ceramic translucency, layer thickness, and substrate colour on the shade of lithium disilicate glass-ceramic restorations proved to be significant in several...
BACKGROUND
Effects of ceramic translucency, layer thickness, and substrate colour on the shade of lithium disilicate glass-ceramic restorations proved to be significant in several studies, however, quantitative, numerical results on the relationship between the colour difference and these parameters are still lacking. The purpose of this in vitro study was to quantitatively determine how the colour reproduction ability of a lithium disilicate glass-ceramic is affected by its translucency, layer thickness, and substrate colour.
METHODS
Ceramic samples were prepared from A2 shade IPS e.max CAD blocks with high and low translucencies (HT and LT) in a thickness range of 0.5-2.5 mm (+/- 0.05 mm). Layered samples were acquired utilizing composite substrates in 9 shades; transparent try-in paste was used. The spectral reflectance of the specimens was assessed under D65 standard illumination with a Konica Minolta CM-3720d spectrophotometer. The CIEDE2000 colour difference (ΔE) between two samples was analysed using perceptibility and acceptability thresholds set at 50:50%. Statistical analysis involved linear regression analysis and the Kruskal-Wallis test.
RESULTS
An increase in the thickness of 0.5 mm reduced the ΔE of the HT samples to 72.8%, and that of the T samples to 71.1% (p < 0.0001). 7 substrates with HT and LT specimens had significantly different results from the mean (p < 0.05). A thickness of 0.5 mm is not sufficient to achieve an acceptable result at any level of translucency, while the low translucency ceramic at a thickness of 1.5 mm gave acceptable results, except for severely discoloured substrates (ND8 and ND9).
CONCLUSIONS
The colour reproduction ability of lithium disilicate glass-ceramics is significantly affected by their translucency, layer thickness, and 7 substrates out of 9 substrates examined.
Topics: Dental Porcelain; Ceramics; Color; Prosthesis Coloring; Spectrophotometry; Materials Testing; Humans; Surface Properties
PubMed: 38840111
DOI: 10.1186/s12903-024-04429-w -
Dental Materials Journal Jun 2024The surface treatment of glass-ceramic-based materials, namely, lithium disilicate glass (IPS e.max CAD), feldspar porcelain (VITABLOCS Mark II), and a...
The surface treatment of glass-ceramic-based materials, namely, lithium disilicate glass (IPS e.max CAD), feldspar porcelain (VITABLOCS Mark II), and a polymer-infiltrated ceramic network (VITA ENAMIC), using aqueous fluoride solutions and their influence on luting agent bonding were investigated. Six experimental aqueous fluoride solutions were applied to these materials, and their effects were assessed by surface topological analysis. The obtained results were compared using non-parametric statistical analyses. Ammonium hydrogen fluoride (AHF) etchant demonstrated the greatest etching effect. Subsequent experiments focused on evaluating different concentrations of the AHF etchant for the bonding pretreatment of glass-ceramic-based materials with a luting agent (PANAVIA V5). AHF, particularly at concentrations above 5 wt%, effectively roughened the surfaces of the materials and improved the bonding performance. Notably, AHF at a concentration of 30 wt% exhibited a more pronounced effect on both etching and bonding capabilities compared to hydrofluoric acid.
PubMed: 38825449
DOI: 10.4012/dmj.2023-333 -
BMC Oral Health May 2024Erbium lasers safely offer the possibility of reuse for debonded restorations. Since these lasers have a high affinity for water molecules, they are absorbed by resin...
BACKGROUND
Erbium lasers safely offer the possibility of reuse for debonded restorations. Since these lasers have a high affinity for water molecules, they are absorbed by resin cement causing explosive ablation of the cement and thus, the restoration debonds. The efficiency of this process depends on many factors, including the ceramic type, its chemical composition and thickness. Therefore, this study was designed to test the time taken to debond ultrathin occlusal veneers made of three types of milled ceramic materials and evaluate the integrity of these restorations after debonding.
METHODS
Three ceramic types were evaluated in this study: lithium disilicate (IPS Emax CAD), highly condensed lithium disilicate (GC initial®LiSi), and translucent zirconia (Katana zirconia STML). Each group consisted of 8 occlusal veneers of 0.5 mm thickness. The samples were cemented to the occlusal surfaces of the upper molar teeth. An Er; Cr: YSGG laser was applied to the occlusal veneers using the scanning method, and time until debonding was calculated. The debonded samples were then inspected under a stereomicroscope for possible damage. Numerical data are presented as the mean with 95% confidence interval (CI), standard deviation (SD), minimum (min.) and maximum (max.) values. Normality and variance homogeneity assumptions were confirmed using Shapiro-Wilk's and Levene's tests, respectively. Data were normally distributed and were analyzed using one-way ANOVA followed by Tukey's post hoc test. The significance level was set at p < 0.05 for all tests. Statistical analysis was performed with R statistical analysis software version 4.3.2 for Windows (R Core Team (2023). R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. URL https://www.R-project.org/).
RESULTS
There was no significant difference in debonding time between the different materials (p = 0.995). The longest debonding time was found for Katana STML (87.52 ± 20.45) (seconds), followed by Emax (86.94 ± 20.63) (seconds), while the lowest value was found for LiSi initial (86.14 ± 25.16) (seconds). In terms of damage to the debonded veneers, The Emax and zirconia samples showed no damage. However, 40% of the LiSi samples fractured during debonding, and 20% exhibited cracks. Only 40% of the LiSi samples were sound after debonding.
CONCLUSION
Er; Cr: YSGG laser can be used efficiently to remove ceramic occlusal veneers. However, its effect on LiSi restorations needs further research.
Topics: Dental Veneers; Computer-Aided Design; Ceramics; Dental Porcelain; Humans; Zirconium; Lasers, Solid-State; Dental Debonding; Materials Testing
PubMed: 38802801
DOI: 10.1186/s12903-024-04314-6 -
Cureus Apr 2024Aim This retrospective study aimed to evaluate if E-max veneers over five years caused changes in gingival, periodontal health, and veneer failures. Background As...
Aim This retrospective study aimed to evaluate if E-max veneers over five years caused changes in gingival, periodontal health, and veneer failures. Background As aesthetic dentistry progresses, dental veneers are becoming increasingly popular in both general and specialized dental practices. Due to technological advancements in dental ceramics and adhesive systems, porcelain veneers have become a highly sought-after solution for improving aesthetics in dental patients. The success of porcelain laminate veneers, a commonly used method for aesthetic restoration, relies on various factors. E-max veneers are frequently utilized, with their long-term durability contingent upon factors such as color stability, resistance to abrasion, as well as good compressive, tensile, and shear strength, along with maintaining marginal integrity. Methodology In this study, data was collected through a checklist form used to record clinical parameters. The clinical parameters evaluated were inflammation and bleeding on probing (BOP). The gingival health was evaluated by gingival index, gingival color, texture, and bleeding on probing, and periodontal health was evaluated by the pocket depth and radiographic evaluations. Finally, the veneer was visually inspected for chipping, staining, and debonding history. The score for most of the cases ranged between 0-1, with only 10 cases displaying moderate gingival inflammation and BOP (Gingival Index 2). Siemens Orthopantomogram (OPG) systems were used for radiological evaluation and documentation of cases. E-max porcelain veneers were only included in the research. Results Out of 28 patients, each with 6-to-10-unit veneer cases was examined, 18 patients (64.3%) displayed healthy gingival status with no bleeding area recorded in none of the veneers amongst the 6 to 10 units. In 10 patients (35.7%) most of the veneers had inflamed gingival tissue that was bleeding on probing. The majority revealed the presence of stippling (92.9%), absence of recession (96.4%), and pocket depth (67.9%). Half of our participants had their veneer for more than five years (50%) and the majority presented with no significant changes in veneer recorded like marginal staining, debonding, or chipping (89.3%). Conclusion Multiple factors such as patient selection, proper treatment planning, and design, including material selection, play a significant role in the long-lasting success of ceramic veneers. The retrospective study indicated that proper oral hygiene measures are vital for the long-term sustainability of E max veneers.
PubMed: 38800248
DOI: 10.7759/cureus.58957 -
The International Journal of... May 2024It is incumbent upon our profession to reevaluate our preference for routinely replacing a missing single maxillary incisor, especially a maxillary lateral incisor, with...
It is incumbent upon our profession to reevaluate our preference for routinely replacing a missing single maxillary incisor, especially a maxillary lateral incisor, with a dental implant in a young adult. The dental literature is replete with beautiful restorative results using implants in this area, but there is minimal discussion regarding the long-term consequences of this treatment. The maxillary lateral incisor is one of the most commonly missing teeth due to agenesis, and it is also one of the most common teeth to be lost due to trauma in the developing child.1 Therefore, the decision for replacement must be made with the long-term in mind, as these restorations are commonly placed between ages 18 and 21 and must serve the patient for many decades. There are several reasons that implants can be associated with complications or even fail, including the following: (1) Continued craniofacial growth, which has a predominant anterior and vertical component and has been shown to occur in the maxilla, resulting in the apparent submersion of the implant crown as the natural teeth move incisally in relation to the implant2,3-there is no evidence that this can be predicted, let alone how far into the future it may happen; (2) peri-implantitis, which has a patient-level prevalence estimate of nearly 25% according to the findings of a recent systematic review;4 (3) thinning and recession of the peri-implant mucosa due to poor implant placement, inadequate prosthetic management, and/or poor case selection, often resulting in compromised esthetics and a predisposition for the onset and progression of peri-implant diseases; and (4) mechanical failure of the implant, abutment screw, transmucosal abutment, and/or crown. Clinicians should also keep in mind that, once an implant is placed in the anterior maxilla, it precludes the possibility for palatal expansion in the adult patient because the space created by the expansion cannot be redistributed orthodontically. Canine substitution is one traditional method for replacement of the missing maxillary lateral incisor. It is still a viable option when the canine tooth has an acceptable shape and color, and the occlusion will not be compromised by the substitution.5 Additionally, the bonded single-wing zirconia bridge has become a primary treatment option.6 Zirconia has the strength of metal and beauty of porcelain, which makes it an ideal substrate for a bonded bridge. The literature has demonstrated the long-term success of this replacement option for the missing maxillary incisor.7 There are clearly many potential long-term disadvantages associated with replacing a single missing maxillary incisor with an implant in young adults. We should be prescribing the least-invasive treatment option for the replacement of these teeth. Therefore, when treatment-planning for a missing maxillary incisor in a young adult, alternatives to implant therapy-such as the bonded single-wing zirconia bridge and canine substitution-should be the primary treatment options. The implant should only be considered as a secondary treatment when the other options are not viable or have previously failed.
Topics: Humans; Incisor; Maxilla; Dental Implants, Single-Tooth; Anodontia; Young Adult; Dental Prosthesis, Implant-Supported; Peri-Implantitis
PubMed: 38787712
DOI: 10.11607/prd.2024.3.e -
The Journal of Adhesive Dentistry Jan 2024To measure zirconia-to-zirconia microtensile bond strength (µTBS) using composite cements with and without primer.
PURPOSE
To measure zirconia-to-zirconia microtensile bond strength (µTBS) using composite cements with and without primer.
MATERIALS AND METHODS
Two Initial Zirconia UHT (GC) sticks (1.8x1.8x5.0 mm) were bonded using four cements with and without their respective manufacturer's primer/adhesive (G-CEM ONE [GOne] and G-Multi Primer, GC; Panavia V5 [Pv5]), and Panavia SA Cement Universal [PSAu], and Clearfil Ceramic Plus, Kuraray Noritake; RelyX Universal (RXu) and Scotchbond Universal Plus [SBUp], 3M Oral Care). Specimens were trimmed to an hour-glass shaped specimen whose isthmus is circular in cross-section. After 1-week water storage, the specimens were either tested immediately (1-week μTBS) or first subjected to 50,000 thermocycles (50kTC-aged μTBS). The fracture mode was categorized as either adhesive interfacial failure, cohesive failure in composite cement, or mixed failure, followed by SEM fracture analysis of selected specimens. Data were analyzed using linear mixed-effects statistics (α = 0.05; variables: composite cement, primer/adhesive application, aging).
RESULTS
The statistical analysis revealed no significant differences with aging (p = 0.3662). No significant difference in µTBS with/without primer and aging was recorded for GOne and PSAu. A significantly higher µTBS was recorded for Pv5 and RXu when applied with their respective primer/adhesive. Comparing the four composite cements when they were applied in the manner that resulted in their best performance, a significant difference in 50kTC-aged μTBS was found for PSAu compared to Pv5 and RXu. A significant decrease in µTBS upon 50kTC aging was only recorded for RXu in combination with SBUp.
CONCLUSION
Adequate bonding to zirconia requires the functional monomer 10-MDP either contained in the composite cement, in which case a separate 10-MDP primer is no longer needed, or in the separately applied primer/adhesive.
Topics: Zirconium; Tensile Strength; Dental Bonding; Resin Cements; Materials Testing; Composite Resins; Methacrylates; Dental Cements; Ceramics; Dental Stress Analysis; Humans; Time Factors; Water; Temperature; Dental Porcelain; Surface Properties; Dental Materials; Glass Ionomer Cements
PubMed: 38771025
DOI: 10.3290/j.jad.b5362103 -
The Journal of Adhesive Dentistry Jan 2024To investigate the effect of adhesive type and long-term aging on the shear bond strength (SBS) between silica-based ceramics and composite cement (CC).
PURPOSE
To investigate the effect of adhesive type and long-term aging on the shear bond strength (SBS) between silica-based ceramics and composite cement (CC).
MATERIALS AND METHODS
Lithium-silicate (LS), feldspathic (FD) and polymer-infiltrated ceramic (PIC) blocks were sectioned (10 x 12 x 2 mm) and divided into 24 groups considering the factors: "ceramics" (LS, FD, and PIC), "adhesive" (Ctrl: without adhesive; 2SC: 2-step conventional; 3SC: 3-step conventional; 1SU: 1-step universal), and "aging" (non-aged or aged [A]). After the surface treatments, CC cylinders (n = 15, Ø = 2 mm; height = 2 mm) were made and half of the samples were subjected to thermocycling (10,000) and stored in water at 37°C for 18 months. The samples were submitted to SBS testing (100 kgf, 1 mm/min) and failure analysis. Extra samples were prepared for microscopic analysis of the adhesive interface. SBS (MPa) data was analyzed by 3-way ANOVA and Tukey's test (5%). Weibull analysis was performed on the SBS data.
RESULTS
All factors and interactions were significant for SBS (p<0.05). Before aging, there was no significant difference between the tested groups and the respective control groups. After aging, the LS_1SU (22.18 ± 7.74) and LS_2SC (17.32 ± 5.86) groups exhibited significantly lower SBS than did the LS_Ctrl (30.30 ± 6.11). Only the LS_1SU group showed a significant decrease in SBS after aging vs without aging. The LS_1SU (12.20) group showed the highest Weibull modulus, which was significantly higher than LS_2SC_A (2.82) and LS_1SU_A (3.15) groups.
CONCLUSION
No type of adhesive applied after silane benefitted the long-term adhesion of silica-based ceramics to CC in comparison to the groups without adhesive.
Topics: Silicon Dioxide; Ceramics; Dental Bonding; Shear Strength; Time Factors; Materials Testing; Resin Cements; Computer-Aided Design; Surface Properties; Dental Stress Analysis; Cementation; Dental Porcelain; Humans; Composite Resins; Dental Cements; Potassium Compounds; Aluminum Silicates; Temperature
PubMed: 38770704
DOI: 10.3290/j.jad.b5341383