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Item Extrinsic Characterization Sustainability in Zirconia Reinforced Lithium Silicate Ceramics(2021-04-08) Gadah, Thrya; May, Jaren; Levon, John; Chu, Tien-Min G; Gregory, Richard; Wei Shao, Lin; Feitosa, SabrinaABSTRACT OBJECTIVE. To investigate the effect of aging on the surface roughness and the color sustainability of externally characterized zirconia reinforced lithium silicate glass-ceramics treated with different surface protocols. METHODS. Sixty blocks (12-mm X 14-mm; 1.5-mm) of pre-crystalized zirconia reinforced-lithium silicate glass-ceramic (Vita Suprinity, Vita Zahnfabrick, Germany) CAD/CAM were crystalized and treated with different surface protocols, as extrinsic characterization (EC), mechanical polishing (MP), glaze layer (GL), surface adjustment (SA) and no treatment – control group (CG). Experimental groups (n=10) were divided as follow: CG; EC-MP-GZ; EC-GZ; EC-MP; EC-GZ-SA-GZ; EC-GZ-SA-MP and submitted to thermocycling (5,000 cycles, 5-55C) and toothbrushing simulation (5,000 cycles). Surface roughness (Ra and Rq), color change (CIED2000) and biofilm growth were evaluated. Statistical analysis was performed with a two-sided 5% significance level for all tests. RESULTS. For the parameter RaX, the control differed from EC-GZ and EC-MP (p = 0.04). For the parameter RqX, EC-GZ presented higher surface roughness compared than EC-MP-GZ and the group EC-GZ-SA-MP (p=0.02). EC-MP (p<0.01) and the EC-GZ-SA-MP (p<0.01) showed higher color change E00 after aging, while CG and EC-MP-GZ the least. For the biofilm growth, no significant group effect on bacteria counts was found (p=0.089). CONCLUSION. The aging protocol affected the surface roughness, and color of externally characterized zirconia reinforced lithium silicate glass-ceramics submitted to different surface treatment protocols. In the present study, when the mechanical polishing was performed before glaze application, the slightest color change and surface roughness were observed compared to the other surface treatments. Bacteria were not able to grow in the material surface, under the conditions tested in the present study.Item Virtual Facial Simulation of Prosthetic Outcome for Static Computer-Aided Implant Surgery and CAD-CAM Prostheses(Allen Press, 2022-02) Harris, Bryan T.; Yang, Chao-Chieh; Morton, Dean; Lin, Wei-Shao; Prosthodontics, School of DentistryItem CAD-CAM Hollow Obturator Prosthesis: A Technical Report(Wiley, 2022) Alfaraj, Amal; Su, Fang-Yu; Lin, Wei-Shao; Prosthodontics, School of DentistryAn obturator with a hollow bulb can decrease the overall weight of the prosthesis, stress on the underlying tissues, and patient discomfort. Although many techniques and materials have been proposed in the literature for hollowing the obturator prosthesis, they are often time-consuming and technique sensitive. This proposed technique used an open-source software program to hollow digital design of solid obturator base from a commercially available software in one single convenient step. The hollowing process allowed precise control of prosthesis thickness at the hollow space area for desirable hermetic seal and prosthesis strength.Item Evaluation of the accuracy of the soft tissue thickness measurements with three different methodologies: an in-vitro study(Wiley, 2022) Ferry, Katherine; AlQallaf, Hawra; Blanchard, Steven; Dutra, Vinicius; Lin, Wie-Shao; Hamada, Yusuke; Prosthodontics, School of DentistryBackground Soft tissue thickness (STT) influences esthetics, peri-implant, and periodontal health. Non-invasive methods of STT evaluation include cone-beam computed tomography (CBCT) with Digital Imaging and Communications in Medicine (DICOM) files and registration of DICOM files with an intraoral scan or Standard Tessellation Language (STL) files. This study compares three methodologies: bone sounding, DICOM data alone, and DICOM and STL registration to absolute histomorphologic values. Materials and Methods Five human maxillas, including teeth #s 6-11, provided 90 sites for analysis. For standardization, reference grooves were placed at the cervical margin and the long axis of each tooth. Direct measurements with a no. 25 K-file were completed at the facial soft tissues at 3.00, 5.00, and 7.00 mm from the apical marginal reference. Indirect measures were performed with implant planning software. Histological measurements were rendered with imaging software. One-way analysis of variance (ANOVA) was used to compare the three techniques for the differences from histologic measurements (α = .05). Results Seventy-two sites were included for final analysis. The overall mean histological STT (mSTT) was 0.73 ± 0.31 mm. Bone sounding overestimated mSTT, 0.22 ± 0.20mm (p<.001); whereas, DICOM alone underestimated mSTT, -0.23 ± 0.19 mm (p<.001). DICOM and STL registration had non-statistically significant differences, -0.04 ± 0.21mm (p = .429). Intraclass correlation coefficient (ICC) of DICOM and STL registration achieved the highest agreement with histology (ICC: 0.74). Conclusions DICOM and STL file registration had the highest agreement with histological STT supporting the use of DICOM and STL registration for the evaluation of soft tissue thickness.Item An investigation into the potential anticaries benefits and contributions to mineral intake of bottled water(Elsevier, 2020-12) Almejrad, Lamya; Levon, John A.; Soto-Rojas, Armando E.; Tang, Qing; Lippert, Frank; Prosthodontics, School of DentistryBACKGROUND: Bottled water has become the most consumed beverage in the United States. The authors aimed to inform the dental profession about the potential anticaries benefits of some bottled waters and to provide information about their possible contributions to fluoride, calcium, magnesium, sodium, and potassium intakes. METHODS: The authors chose a convenience sample by purchasing all different bottled waters from the main supermarkets operating in Indianapolis, Indiana. The authors analyzed the fluoride content using a fluoride ion-specific electrode and metal concentrations using atomic absorption spectroscopy. They used dietary reference intakes to calculate hypothetical intakes of all minerals. RESULTS: The authors identified 92 different bottled waters. Fluoride concentrations were generally low (mean, 0.11 parts per million [ppm]; median, 0.04 ppm). Only 2 waters contained more than 0.7 ppm fluoride (0.95 ppm and 1.22 ppm). Metal concentrations varied considerably among waters. Calcium concentrations ranged from less than 0.1 through 360 ppm (mean, 26.9 ppm; median, 5.2 ppm), which were greater than those of magnesium (range, < 0.01-106 ppm; mean, 7.5 ppm; median, 1.9 ppm), sodium (range, < 0.01-109 ppm; mean, 11.1 ppm; median, 2.9 ppm), and potassium (range, < 0.01-43 ppm; mean, 3.6 ppm; median, 1.2 ppm). Overall, most bottled waters do not contribute to adequate intakes of fluoride, potassium, or sodium or to recommended dietary allowances for calcium and magnesium. Nonetheless, some waters can provide meaningful contributions to fluoride, calcium, and magnesium intake. CONCLUSIONS: The fluoride concentration in 90 of the 92 studied bottled waters is insufficient to contribute to caries prevention. Only a few bottled waters can be considered health-promoting. PRACTICAL IMPLICATIONS: Dental professionals should consider the mineral content of water consumed by their patients during caries risk assessment.Item Use of a CAD‐CAM Surgical Template to Improve Accuracy for Simultaneous Implant Removal, New Implant Placement, and Bone Graft(Wiley, 2021) Gadah, Thuraya; Dutra, Vinicius; Polido, Waldemar; Al‐Shahrani, Ahid; Lin, Wei‐Shao; Morton, Dean; Prosthodontics, School of DentistryA fractured implant is considered a catastrophic failure that leads to the loss of the implant and the prosthesis. Available methods of implant removal include the reverse screw technique, use of trephines, or osteotomies around the implant. In case of a fractured implant, the access hole for the reverse screw technique is impossible, leading to the need for an osteotomy. When the apical part of the fractured implant is embedded in bone, finding the piece may lead to a more ample osteotomy and significant bone loss, complicating future implant placement. This technique presented utilized a CAD-CAM surgical template that was designed with the purpose of improving accuracy in finding the fractured part with minimal osteotomy, allowing for simultaneous placement of a new implant in the same site, with additional bone graft, utilizing the same template.Item Fracture Resistance Behaviors of Titanium-Zirconium and Zirconia Implants(Wiley, 2021) Hanes, Brenda; Sochacki, Sabrina Feitosa; Phasuk, Kamolphob; Levon, John A.; Morton, Dean; Lin, Wei-Shao; Prosthodontics, School of DentistryPurpose To evaluate the fracture resistance behaviors of titanium-zirconium, one-piece zirconia, and two-piece zirconia implants restored by zirconia crowns and different combinations of abutment materials (zirconia and titanium) and retention modes (cement-retained and screw-retained zirconia crowns). Material and Methods Three research groups (n=12) were divided according to combinations of abutment material, retention mode, and implant type. In the control group (TTC), titanium-zirconium implants (∅ 4.1 mm RN, 12 mm, Roxolid; Straumann USA) and prefabricated titanium abutments (RN synOcta Cementable Abutment, H 5.5 mm; Straumann USA) were used to support cement-retained zirconia crowns. In the second group (ZZC), one-piece zirconia implants (PURE Ceramic Implant Monotype, ∅ 4.1 mm RD, 12 mm, AH 5.5 mm; Straumann USA) were used to support cement-retained zirconia crowns. In the third group (ZTS), two-piece zirconia implants (PURE Ceramic Implant, ∅ 4.1 mm RD, 12 mm) and prefabricated titanium abutments (CI RD PUREbase Abutment, H 5.5 mm) were used to support screw-retained zirconia crowns. All zirconia crowns were manufactured in the same anatomic contour with a 5-axis dental mill and blended 3 and 5 mol% yttria-stabilized zirconia (LayZir A2). Implants were inserted into specimen holders made of epoxy resin-glass fiber composite. All specimens were then subject to artificial aging in an incubator at 37 C° for 90 days. Fracture resistance of specimen assemblies was tested under static compression load using the universal testing machine following ISO14801 specification. The peak fracture loads were recorded. All specimens were examined at the end of the test microscopically at 5 × and 10 × magnification to detect any catastrophic failures. Comparisons between groups for differences in peak fracture load were made using Wilcoxon Rank Sum tests and Weibull and Kaplan-Meier survival analyses (α = .05). Results The TTC group (942 ±241 N) showed significantly higher peak fracture loads than the ZZC (645 ±165 N) and ZTS (650 ±124 N) groups (p < .001), while there was no significant difference between ZZC and ZTS groups (p = 0.940). The survival probability based on the Weibull and Kaplan-Meier models demonstrated different failure molds between titanium- zirconium and zirconia implants, in which the TTC group remained in the plastic strain zone for a longer period before fracture when compared to ZZC and ZTS groups. Catastrophic failures, with implant fractures at the embedding level or slightly below, were only observed in the ZZC and ZTS groups. Conclusions Cement-retained zirconia crowns supported by titanium-zirconium implants and prefabricated titanium abutments showed superior peak fracture loads and better survival probability behavior. One-piece zirconia implants with cement-retained zirconia crowns and two-piece zirconia implants with screw-retained zirconia crowns on prefabricated titanium abutment showed similar peak fracture loads and survival probability behavior. Titanium-zirconium and zirconia implants could withstand average intraoral mastication loads in the incisor region. This study was conducted under static load, room temperature (21.7 °C), and dry condition, and full impacts of intraoral hydrothermal aging and dynamic loading conditions on the zirconia implants should be considered and studied further.Item Curcumin—A Natural Medicament for Root Canal Disinfection: Effects of Irrigation, Drug Release, and Photoactivation(Elsevier, 2019-11) Sotomil, Julian M.; Münchow, Eliseu A.; Pankajakshan, Divya; Spolnik, Kenneth J.; Ferreira, Jessica A.; Gregory, Richard L.; Bottino, Marco C.; Prosthodontics, School of DentistryIntroduction Curcumin incorporation into polymeric fibers was tested for its antimicrobial properties and potential use in root canal disinfection. Methods Curcumin-modified fibers were processed via electrospinning and tested against a 7-day old established Actinomyces naeslundii (An) biofilm. The medicaments tested were as follows: curcumin-modified fibers at 2.5 and 5.0 mg/mL, curcumin-based irrigant at 2.5 and 5.0 mg/mL, saline solution (negative control), and the following positive controls: 2% chlorhexidine, 1% NaOCl, and triple antibiotic paste (TAP, 1 mg/mL). All medicaments, except for the positive controls, were allocated according to the light exposure protocol: photoactivation with an LED every 30 s for 4 min or without photoactivation. After treatment, the medicaments were removed and 1 mL of saline solution was added; the biofilm was scraped from the well and used to prepare a 1:2000 dilution. Spiral plating was done using anaerobic blood agar plates. After 24 h, colony-forming units (CFU/mL, n=11/group) were counted to determine the antimicrobial effects. Results Data exhibited significant antimicrobial effects on positive control groups, followed by the curcumin irrigants, and lastly, the photoactivated curcumin-modified fibers. There was a significant reduction of viable bacteria in curcumin-based irrigants, which was greater than the TAP-treated group. Curcumin-free fibers, saline, and the non-photoactivated curcumin-modified fibers did not display antimicrobial activity. Conclusions Curcumin seems to be a potential alternative to TAP when controlling infection, but it requires a minimal concentration (2.5 mg/mL) to be effective. Photoactivation of curcumin-based medicaments seems to be essential to obtain greater antibiofilm activity.Item The Trueness of Obturator Prosthesis Base Manufactured by Conventional and 3D Printing Techniques(Wiley, 2021) Alfaraj, Amal; Yang, Chao-Chieh; Levon, John A.; Chu, Tien-Min G.; Morton, Dean; Lin, Wei-Shao; Prosthodontics, School of DentistryPurpose : To compare the intaglio surface trueness of obturator prosthesis bases manufactured by traditional compression molding, injection molding, and 3D printing techniques. Materials and Methods : A complete edentulous master cast with Aramany Class I maxillary defect was selected for this in vitro study. Four study groups (n = 10/group) were included in this study, Group A: Compression Molding, Group B: Injection Molding, and Group C: Cara Print 3D DLP Printer, and Group D: Carbon 3D DLS Printer. All obturator prostheses' intaglio surfaces were scanned with a laboratory scanner (E4; 3Shape Inc, New Providence, NJ) and the dimensional differences between study samples and their corresponding casts were calculated as the root mean square (measured in mm, absolute value) using a surface matching software (Geomagic design X; 3D Systems, Rock Hill, SC). One-way Analysis of variance (ANOVA) and Fisher's least significant difference (LSD) test were used to compare groups differences in RMS (α = .05). Results There was a significant effect of manufacturing technique on the RMS values for the 4 conditions [F(3,36) = 5.743, p = .003]. Injection Molding (0.070 mm) and Compression Molding groups (0.076 mm) had a lower interquartile range, and the Cara Print 3D-Printer group (0.427 mm) and Carbon 3D-Printer (0.149 mm) groups had a higher interquartile range. The Injection Molding group showed the best and uniform surface matching with the most area in green in the color maps. The Injection Molding group (0.139 ±0.049 mm) had significantly lower RMS than all other groups (p<.001 for all comparisons). Compression Molding (0.269 ±0.057 mm), Cara Print 3D-Printer (0.409 ±0.270 mm), and Carbon 3D-Printer (0.291 ±0.082 mm) groups were not significantly different from each other (Compression Molding versus Carbon 3D-Printer, p = .59; Compression Molding versus Cara Print 3D-Printer, p = .25; Cara Print 3D-Printer versus Carbon 3D-Printer, p = .40). Conclusion : Obturator prosthesis bases manufactured with injection molding technique showed better intaglio surface trueness than ones made by the compression molding technique and 3D printers. Although obturator prosthesis bases manufactured from different 3D printers showed similar trueness, a DLP 3D printer produced less consistent outcome than a DLS 3D printer.Item Using an existing surgical template as an aid for a virtual interocclusal record(Elsevier, 2020-09) Lin, Wei-Shao; AlQallaf, Hawra; Morton, Dean; Prosthodontics, School of DentistryA satisfactory complete denture can be duplicated with acrylic resin to preserve the information on the patient’s occlusal vertical dimension, occlusal relationship, and tooth arrangement during preoperative planning for dental implant treatment.1 The duplicated denture can be used as a radiographic template, surgical template, and occlusally adapted custom tray.2 A dual scan protocol with the existing complete denture and additively manufactured surgical template (in the shape of a duplicated denture) is commonly used in contemporary static computer-aided implant surgery (s-CAIS). Occlusion with the opposing arch is often needed to properly position these surgical templates before the s-CAIS.3 As these surgical templates are designed and manufactured from the 3D volumetric data of the existing denture, preserving the interocclusal relationship, this technique allows the clinicians to use the surgical template as an aid to obtain a virtual interocclusal record during intraoral scanning. The acquired intraoral scan and virtual interocclusal record can be used for fabricating a computer-aided design and computer-aided manufacturing (CAD-CAM) implant prosthesis.