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The International Journal of... Apr 2024To evaluate the marginal integrity of three inlay-retained fixed dental prosthesis (IRFDP) designs fabricated using monolithic zirconia.
PURPOSE
To evaluate the marginal integrity of three inlay-retained fixed dental prosthesis (IRFDP) designs fabricated using monolithic zirconia.
MATERIALS AND METHODS
In total, 30 IRFDPs were fabricated using 4-YTZP monolithic zirconia and randomly divided into three groups according to the cavity design. Groups ID2 and ID1.5 received an inlay cavity preparation, which includes a proximal box and an occlusal extension with a depth of 2 mm or 1.5 mm, respectively. Group PB received a proximal box cavity preparation without an occlusal extension. The restorations were fabricated and cemented using a dual-cure resin cement (Panavia V5) and subjected to an equivalent of 5 years of aging. The specimens were evaluated under an SEM to measure marginal continuity before and after the aging process.
RESULTS
During the whole 5-year aging process, no specimens showed signs of cracking, fracture, or loss of retention in any restorations. In the SEM analysis, most marginal defects observed in the restorations were areas of microgaps at the tooth/cement interface (TC) or zirconia/cement interface (ZC), resulting in loss of adaptation. There was a significant difference between the groups after the aging process at both the TC (F = 4.762, P < .05) and ZC (F = 6.975, P < .05), with Group ID2 presenting the best performance. There was a significant difference between TC and ZC in all groups (P < .05), with ZC presenting more gaps in all groups.
CONCLUSIONS
Inlay cavity designs including a proximal box and an occlusal extension exhibited better marginal stability than a proximal box without occlusal extension.
Topics: Zirconium; Inlays; Humans; In Vitro Techniques; Dental Marginal Adaptation; Dental Prosthesis Design; Denture Design; Denture, Partial, Fixed; Dental Materials
PubMed: 38648165
DOI: 10.11607/ijp.7875 -
Dental Materials Journal Jun 2024This study aimed to evaluate the effects of different resin-coating technique strategies and dual-cure resin luting materials on proximal marginal adaptation and the...
This study aimed to evaluate the effects of different resin-coating technique strategies and dual-cure resin luting materials on proximal marginal adaptation and the microtensile bond strengths (μTBSs) of CAD/CAM hybrid ceramic inlays. Extracted human molars were classified into four groups, depending on the coating technique: No coating (None), single coating (1-coating), double coating (2-coating), and flowable resin-coating (Combination). The inlays were bonded with one of the three materials: Panavia V5 (V5), Rely X Ultimate (RXU), and Calibra Ceram (CC). The differences with regard to adaptation were not significant. In the case of μTBS data for V5, no significant differences were observed, whereas for RXU, μTBS values for Combination statistically exceeded those for None and 1-coating. For CC, μTBS values for Combination statistically exceeded those for None, 1-coating, and 2-coating. The coating techniques did not influence the adaptation but influenced the bond strength, and Combination performed the best.
Topics: Inlays; Computer-Aided Design; Humans; Materials Testing; Tensile Strength; Ceramics; Dental Marginal Adaptation; Dental Bonding; Surface Properties; Resin Cements; Molar; In Vitro Techniques; Dental Stress Analysis; Dental Porcelain
PubMed: 38644215
DOI: 10.4012/dmj.2023-182 -
Contact Lens & Anterior Eye : the... Apr 2024It is important to be able to measure the range of clear focus in clinical practice to advise on presbyopia correction techniques and to optimise the correction power....
It is important to be able to measure the range of clear focus in clinical practice to advise on presbyopia correction techniques and to optimise the correction power. Both subjective and objective techniques are necessary: subjective techniques (such as patient reported outcome questionnaires and defocus curves) assess the impact of presbyopia on a patient and how the combination of residual objective accommodation and their natural DoF work for them; objective techniques (such as autorefraction, corneal topography and lens imaging) allow the clinician to understand how well a technique is working optically and whether it is the right choice or how adjustments can be made to optimise performance. Techniques to assess visual performance and adverse effects must be carefully conducted to gain a reliable end-point, considering the target size, contrast and illumination. Objective techniques are generally more reliable, can help to explain unexpected subjective results and imaging can be a powerful communication tool with patients. A clear diagnosis, excluding factors such as binocular vision issues or digital eye strain that can also cause similar symptoms, is critical for the patient to understand and adapt to presbyopia. Some corrective options are more permanent, such as implanted inlays / intraocular lenses or laser refractive surgery, so the optics can be trialled with contact lenses in advance (including differences between the eyes) to better communicate with the patient how the optics will work for them so they can make an informed choice.
PubMed: 38641525
DOI: 10.1016/j.clae.2024.102156 -
Journal of Pharmacy & Bioallied Sciences Feb 2024Surface roughness of the crowns is dependent on the pattern material used for the making as well as the procedure of investing. The study was aimed to examine the impact...
INTRODUCTION
Surface roughness of the crowns is dependent on the pattern material used for the making as well as the procedure of investing. The study was aimed to examine the impact of various pattern materials and investment procedures on the surface roughness of nickel-chromium alloy raw castings.
MATERIALS AND METHODS
An study was piloted at a tertiary care hospital. Eighty samples of inlay wax and pattern resin were divided equally. They were invested in phosphate-bonded investment material and kept under normal atmospheric pressure as well as invested under a pressure of 3 bars. The surface roughness was calculated with a Profilometer. The values obtained were compared using statistical tools keeping < 0.05 as significant.
RESULTS
Lowest surface roughness was seen for the wax pattern invested under positive pressure. While the highest was seen for the resin patterns invested at room pressure. A significant variance between the wax 1 and wax 2 ( < 0.01); as well as between the wax 2 vs. Resin 2 specimens ( < 0.01) was noted.
CONCLUSIONS
Wax patterns can be suggested as the material and method of choice because they showed the least amount of surface roughness when placed under pressure. Resin patterns when invested under pressure can also be suggested as an alternate as they also exhibited similar surface roughness as that of the wax.
PubMed: 38595557
DOI: 10.4103/jpbs.jpbs_445_23 -
Journal of Pharmacy & Bioallied Sciences Feb 2024Indirect composite restoration is one of the commonly followed procedures in the posterior teeth. The success of this is dependent on many factors, one being the luting...
INTRODUCTION
Indirect composite restoration is one of the commonly followed procedures in the posterior teeth. The success of this is dependent on many factors, one being the luting cement. Hence, the current study explores the microleakage of the two luting cements at 2 different times.
MATERIALS AND METHODS
Eighty extracted human teeth were taken, and class II cavities were made that were to receive the composite inlays. They were grouped as supragingival and subgingival, which for further divided as were further subdivided to be observed for marginal leakage at cervical and occlusal margins, at the end of a day and 1 month. Each group had ten specimens. The luting cements that were evaluated were Variolink N and RelyX Unicem. After the composite inlay restoration was done for all the specimens, the sections were put on slides, and a stereomicroscope was used to measure the amount of dye penetration. Leakage was evaluated and compared using Mann-Whitney U test.
RESULTS
At the end of 1 day, there was no significant alteration in the microleakage in the occlusal or cervical regions for either region supragingivally or subgingivally between the two luting cements. Significant difference between the two cements at the cervical borders at the end of a month was seen for both the margins. When compared supragingivally and subgingivally at the end of 1 day or at the end of 1 month, there was not a significant difference for any of the cements.
CONCLUSION
Within the constraints of the current investigation, it can be said that there was similar microleakage for both Variolink N and RelyX Unicem at the conclusion of a day's storage time. After a 1-month storage period, RelyX Unicem showed more cervical microleakage than Variolink N.
PubMed: 38595365
DOI: 10.4103/jpbs.jpbs_438_23 -
Journal of Esthetic and Restorative... Mar 2024To assess the feasibility of producing 3D-printed intracoronal restorations, thin and ultrathin veneers, and to compare their mechanical behavior, accuracy, biological,... (Review)
Review
3D-printed intracoronal restorations, occlusal and laminate veneers: Clinical relevance, properties, and behavior compared to milled restorations; a systematic review and meta-analysis.
OBJECTIVES
To assess the feasibility of producing 3D-printed intracoronal restorations, thin and ultrathin veneers, and to compare their mechanical behavior, accuracy, biological, and stain susceptibility to the currently applied milled restorations.
MATERIALS AND METHODS
The databases were comprehensively searched for relevant records up to January 2024 without language restrictions. All studies that assessed 3D-printed partial coverage restorations including inlays, onlays, laminate, and occlusal veneers were retrieved.
RESULTS
The web search yielded a total of 1142 records, with 8 additional records added from websites at a later stage. Only 17 records were ultimately included in the review. The included records compared 3D-printed; alumina-based- and zirconia ceramics, lithium disilicate ceramics, polymer infiltrated ceramics, polyetheretherketone (PEEK), resin composites, and acrylic resins to their CNC milled analogs. The pooled data indicated that it is possible to produce ultrathin restorations with a thickness of less than 0.2 mm. 3D-printed laminate veneers and intracoronal restorations exhibited superior trueness, as well as better marginal and internal fit compared to milled restorations (p < 0.05). However, it should be noted that the choice of materials and preparation design may influence these outcomes. In terms of cost, the initial investment and production expenses associated with 3D printing were significantly lower than those of CNC milling technology. Additionally, 3D printing was also shown to be more time-efficient.
CONCLUSIONS
Using additive manufacturing technology to produce restorations with a thickness ranging from 0.1 to 0.2 mm is indeed feasible. The high accuracy of these restorations, contributes to their ability to resist caries progression, surpassing the minimum clinical threshold load of failure by a significant margin and reliable adhesion. However, before 3D-printed resin restorations can be widely adopted for clinical applications, further improvements are needed, particularly in terms of reducing their susceptibility to stains.
CLINICAL SIGNIFICANCE
3D-printed intracoronal restorations and veneers are more time and cost-efficient, more accurate, and could provide a considerable alternative to the currently applied CNC milling. Some limitations still accompany the resin materials, but this could be overcome by further development of the materials and printing technology.
PubMed: 38551205
DOI: 10.1111/jerd.13228 -
Materials (Basel, Switzerland) Mar 2024The study aimed to assess the marginal, axial, and internal adaptation, as well as the fracture resistance of zirconia-reinforced lithium silicate (ZLS) endocrowns with...
The study aimed to assess the marginal, axial, and internal adaptation, as well as the fracture resistance of zirconia-reinforced lithium silicate (ZLS) endocrowns with varying pulpal inlay extensions and marginal geometry. Sixty extracted maxillary first molar teeth were divided into six groups (n = 10) according to pulpal inlay extension and marginal configuration. The first three groups (J2, J3, and J4) utilized prepared teeth for endocrowns without ferrule design and 2 mm, 3 mm, and 4 mm pulpal extensions, respectively. The second three groups (F2, F3, and F4) utilized prepared teeth with 1 mm shoulder margins and 2 mm, 3 mm, and 4 mm pulpal extensions. The endocrowns were fabricated from ZLS blocks using CAD/CAM milling technology. After cementation, the specimens underwent thermal aging for 5000 cycles and were evaluated for marginal adaptation. Using a universal testing machine, the fracture resistance was tested under quasistatic loading (1 mm/min). Two-way ANOVA and the Tukey's post hoc test were employed for data analysis ( ≤ 0.05). The results of this study revealed that endocrowns without ferrule exhibited superior fracture strength than a 1 mm ferrule design < 0.05, irrespective of the inlay depth. All designs with and without ferrule and all inlay depths showed clinically acceptable marginal and internal fit. The conventional endocrown design without ferrule and 2 mm inlay depth showed the lowest surface gap. The pulpal surface showed the highest discrepancy among all groups compared to the other surfaces. Endocrowns without ferrule are more conservative and have higher fracture strength than 1 mm ferrule designs; extending the inlay depth showed a significant increase in fracture resistance of the 1 mm ferrule design, but not for the conventional design without ferrule and 2 mm inlay depth. All groups exhibited a high auspicious fracture strength value for molar endocrown restorations.
PubMed: 38541565
DOI: 10.3390/ma17061411 -
The Journal of Contemporary Dental... Feb 2024This study aimed to compare the efficacy of autogenous onlay and inlay grafts for anterior maxillary horizontal ridge augmentation. (Randomized Controlled Trial)
Randomized Controlled Trial
Clinical and Radiographic Outcomes of Autogenous Inlay Graft vs Autogenous Onlay Graft for Anterior Maxillary Horizontal Ridge Augmentation: A Randomized Control Clinical Study.
AIM
This study aimed to compare the efficacy of autogenous onlay and inlay grafts for anterior maxillary horizontal ridge augmentation.
MATERIALS AND METHODS
This randomized clinical trial was performed on 14 patients with a deficient partially edentulous anterior maxillary ridge (3-5 mm in width). Patients were randomized and grouped into two equal groups: Group A was treated with symphyseal autogenous bone block, which was placed and fixed buccally as an onlay graft, and group B: was treated with symphyseal autogenous bone block, which was interpositioned and fixed in space created between buccal and lingual cortex as inlay graft. Patients were evaluated clinically and radiographically to evaluate the increase of bone width at [Baseline, immediate postoperative (T0)] and six months post-graft (T6).
RESULTS
A total of 14 patients (8 males and 6 females) with age range from 20 to 43 years old with a mean of 42.1 years were involved in our study. Radiographically, there was a significant statistical difference in comparing between two groups for the creation of a horizontal alveolar bone at T0. In the inlay group, the mean preoperative bone width was 3.9 ± 0.3 mm at T0 and 5.7 ± 0.5 mm at T6. While in the onlay group, the mean preoperative bone width was 3.7 ± 0.7 mm at T0 while at T6 the mean bone width was 6.1 ± 0.8 mm. This was statistically significant.
CONCLUSION
Inlay block graft appears to be a successful treatment option for horizontal ridge augmentation in the maxillary arch.
CLINICAL SIGNIFICANCE
both techniques are viable techniques for augmentation of atrophic alveolar ridge with uneventful healing. How to cite this article: Elsayed AO, Abdel-Rahman FH, Ahmed WMAS, . Clinical and Radiographic Outcomes of Autogenous Inlay Graft vs Autogenous Onlay Graft for Anterior Maxillary Horizontal Ridge Augmentation: A Randomized Control Clinical Study. J Contemp Dent Pract 2024;25(2):107-113.
Topics: Male; Female; Humans; Young Adult; Adult; Inlays; Bone Transplantation; Alveolar Ridge Augmentation; Alveolar Process; Wound Healing; Maxilla; Dental Implantation, Endosseous
PubMed: 38514406
DOI: 10.5005/jp-journals-10024-3634 -
The International Journal of... Feb 2024To compare the accuracy of 12 different dental restorations fabricated with milling or 3D-printed molds and robotically controlled casting.
PURPOSE
To compare the accuracy of 12 different dental restorations fabricated with milling or 3D-printed molds and robotically controlled casting.
MATERIALS AND METHODS
Twelve dental restorations (11 inlays and onlays and 1 crown) were made per restoration type, one per each of the 12 different teeth models (total of 24 restorations). On each tooth preparation, two restorations were manufactured using different CAD/ CAM techniques: (1) milling and (2) robotically controlled casting and 3D-printed molds. In addition, twolayer restorations were manufactured with 3D-printed molds. The marginal and internal gaps were evaluated at 120 points per restoration based on micro-CT 3D imaging. Internal gaps were evaluated using a replica technique with silicone.
RESULTS
Median values (interquartile ranges) for marginal gaps, middle internal gaps, and central internal gaps were significantly lower for 3D-printed mold restorations (44.3 [65.4] μm, 95.4 [96.2] μm, and 104.6 [78.1] μm) compared to milled restorations (58.4 [93] μm, 145.9 [85.8] μm, and 138.6 [65.7] μm). Internal gaps in the 3D-printed mold group were 6% to 51% smaller than in the milled group.
CONCLUSIONS
The accuracy of restorations fabricated with 3D-printed molds may be preferable compared to milled restorations, except in the case of crown restoration. However, additional studies with a larger number of samples and different types of restorations are needed to confirm the results.
Topics: Pilot Projects; Dental Marginal Adaptation; Computer-Aided Design; Inlays; Crowns; Printing, Three-Dimensional; Dental Prosthesis Design
PubMed: 38498860
DOI: 10.11607/ijp.8236 -
The Journal of Prosthetic Dentistry May 2024The influence of computer-aided manufacturing (CAM) parameters and settings on the outcomes of milled indirect restorations is poorly understood. (Review)
Review
STATEMENT OF PROBLEM
The influence of computer-aided manufacturing (CAM) parameters and settings on the outcomes of milled indirect restorations is poorly understood.
PURPOSE
The purpose of this scoping review was to summarize the current CAM systems, parameters, and setting changes, and their effects on different outcomes of milled indirect restorations and aspects related to their manufacture.
MATERIAL AND METHODS
The protocol of this review is available online (https://osf.io/x28ps/). Studies that used at least 2 different parameters (CAM units, number of axes, digital spacers, or protocols with different rotatory instruments, grit-sizes, milling speed, or others) for milling indirect restorations were included. A structured search up to July 2023 was performed by 2 independent reviewers for articles written in English in LILACS, MEDLINE via PubMed, EMBASE, Web of Science, and Scopus.
RESULTS
Of 1546 studies identified, 22 were included in the review. Discrepancies were found between the planned and actual measured cement space, with a decreasing linear relationship impacting restoration adaptation at different points. The CEREC MC XL milling machine was the most used system in the included studies, with variations in bur types, milling modes, and number of burs uses affecting internal fit and surface trueness. The results demonstrated the better adaptation of restorations made with 5-axis over 3-axis milling machines. Lithium disilicate and zirconia were the most commonly used materials, and crowns and inlays were popular designs. Marginal and internal adaptation were the primary outcomes assessed using the various techniques.
CONCLUSIONS
The study presented a comprehensive exploration of CAM systems and parameters, and their influence on indirect restorations. The planned cement space was not properly reproduced by the milling. Bur characteristics can affect restoration fit and trueness. The 5-axis units seem to result in better-adapted restorations compared with 3- and 4-axis units.
Topics: Computer-Aided Design; Humans; Dental Prosthesis Design; Dental Restoration, Permanent; Dental Marginal Adaptation
PubMed: 38480018
DOI: 10.1016/j.prosdent.2024.02.021