Clinical and mechanical evaluation of a new all-ceramic restorative material Turkon-cera™ / Bandar Mohammed Abdullah Al-Makramani

The mechanical properties and clinical performance of Turkom-Cera system were evaluated in this study. The mechanical properties evaluated were; flexural strength, microhardness, shear bond strength, fracture resistance and marginal integrity. The biaxial flexural strength and hardness of Turkom-Cera compared to two other allceramic systems (In-Ceram and Vitadur-N) were investigated. The Turkom-Cera exhibited significantly higher flexural strength (506.8 MPa) than In-Ceram (347.4 MPa) and Vitadur-N (128.7 MPa) ceramic materials. However, In-Ceram core has significantly higher hardness (1116.2 VHN) than Turkom-Cera (1002.1 VHN) and Vitadur-N (812.8 VHN) all-ceramic materials. In order to find the optimal choice of luting cement and surface treatment for Turkom-Cera all-ceramic material, the shear bond strength of four different luting cements (zinc phosphate, glass ionomer, resin modified glass ionomer and resin cement) to the Turkom-Cera all-ceramic discs was evaluated. In addition, the effect of surface treatments (no treatment as control, sandblasting, silane application and combinations of these treatments) on the shear bond strength of resin cement to Turkom-Cera was also investigated. The shear bond strength increased significantly from zinc phosphate (0.92 MPa), glass ionomer (2.04MPa), resin modified glass ionoer (4.37 MPa) to resin cement (16.42 MPa). Sandblasting followed by silanization of the Turkom-Cera specimens provided the highest bond strength value (19.13 MPa). The control group exhibited significantly lower shear bond strength (10.83 MPa) than the other three groups. However, there were no significant differences in the shear bond strength of the sandblasting (16.42 MPa), silane (16.18 MPa) and sandblasting + silane (19.13 MPa) groups. The occlusal fracture resistance of Turkom-Cera all-ceramic copings compared to Procera AllCeram and In-Ceram all-ceramic copings was evaluated using metal dies and natural teeth as a supporting structure. In both cases, using metal dies or natural teeth as a supporting structure, the mean load at fracture of Turkom-Cera (2184 N / 1341.9 N) was significantly more than Procera (1953.5 N / 975.0 N) (P0.05). The effect of zinc phosphate, glass ionomer and resin cements on the occlusal fracture strength of Turkom-Cera all-ceramic copings were also assessed. The mean load at fracture of Turkom-Cera copings cemented with zinc phosphate, glass ionomer and resin cements were 1537.4 N, 1294.4 N, and 2183.6 N, respectively. There was a significant difference in the mean load at fracture between the three luting cements used (P<0.05). The effect of marginal design (chamfer or shoulder) and artificial ageing (30-day water storage and 500 thermocycles) on the occlusal fracture resistance of Turkom-Cera copings were also investigated. There was no influence of the finish line design and artificial ageing used in this study on the occlusal fracture resistance of Turkom-Cera all-ceramic copings (P<0.05). The marginal adaptation of Turkom-Cera copings compared to In-Ceram and Procera copings was assessed. The mean marginal discrepancy for Turkom-Cera, In-Ceram and Procera were 49.2 μm, 71.5 μm and 34.4 μm, respectively. It was verified that there was a statistically significant difference among the marginal discrepancy of the three allceramic systems (p<0.05). In this study, there were no significant differences in the mean marginal discrepancy of Turkom-Cera crowns between the chamfer (49.2 μm) and shoulder (44.0 μm) groups (p>0.05). A preliminary prospective study to evaluate the clinical performance of Turkom-Cera crowns was conducted. This study was carried out to complement the different mechanical tests that have been done on the Turkom-Cera all-ceramic material. In this study, 20 Turkom-Cera crowns were evaluated for a mean evaluation period of 21.5 months. During the whole observation period, 1 of the 20 Turkom-Cera crowns was found to have fractured after a service time of 14 months. The veneering porcelain chipped in 3 molar crowns, but did not compromise the integrity of the crowns. The other parameters were rated satisfactory according to the Modified United States Public Health Service (USPHS) criteria. All patients expressed satisfaction with their restorations and did not report any sensitivity during or after treatment

Clinical and mechanical evaluation of a new all-ceramic restorative material turkom-cera / Bandar Mohammed Abdullah Al-Makramani

The mechanical properties and clinical performance of Turkom-Cera system were evaluated in this study. The mechanical properties evaluated were; flexural strength, microhardness, shear bond strength, fracture resistance and marginal integrity. The biaxial flexural strength and hardness of Turkom-Cera compared to two other allceramic systems (In-Ceram and Vitadur-N) were investigated. The Turkom-Cera exhibited significantly higher flexural strength (506.8 MPa) than In-Ceram (347.4 MPa) and Vitadur-N (128.7 MPa) ceramic materials. However, In-Ceram core has significantly higher hardness (1116.2 VHN) than Turkom-Cera (1002.1 VHN) and Vitadur-N (812.8 VHN) all-ceramic materials. In order to find the optimal choice of luting cement and surface treatment for Turkom- Cera all-ceramic material, the shear bond strength of four different luting cements (zinc phosphate, glass ionomer, resin modified glass ionomer and resin cement) to the Turkom-Cera all-ceramic discs was evaluated. In addition, the effect of surface treatments (no treatment as control, sandblasting, silane application and combinations of these treatments) on the shear bond strength of resin cement to Turkom-Cera was also investigated. The shear bond strength increased significantly from zinc phosphate (0.92 MPa), glass ionomer (2.04MPa), resin modified glass ionoer (4.37 MPa) to resin cement (16.42 MPa). Sandblasting followed by silanization of the Turkom-Cera specimens provided the highest bond strength value (19.13 MPa). The control group exhibited significantly lower shear bond strength (10.83 MPa) than the other three groups. However, there were no significant differences in the shear bond strength of the sandblasting (16.42 MPa), silane (16.18 MPa) and sandblasting + silane (19.13 MPa) groups. iii The occlusal fracture resistance of Turkom-Cera all-ceramic copings compared to Procera AllCeram and In-Ceram all-ceramic copings was evaluated using metal dies and natural teeth as a supporting structure. In both cases, using metal dies or natural teeth as a supporting structure, the mean load at fracture of Turkom-Cera (2184 N / 1341.9 N) was significantly more than Procera (1953.5 N / 975.0 N) (P<0.05). There were no significant differences in the mean loads at fracture between In-Ceram (2041.7 N / 1151.6 N) and Procera and also between Turkom-Cera and In-Ceram (P>0.05). The effect of zinc phosphate, glass ionomer and resin cements on the occlusal fracture strength of Turkom-Cera all-ceramic copings were also assessed. The mean load at fracture of Turkom-Cera copings cemented with zinc phosphate, glass ionomer and resin cements were 1537.4 N, 1294.4 N, and 2183.6 N, respectively. There was a significant difference in the mean load at fracture between the three luting cements used (P<0.05). The effect of marginal design (chamfer or shoulder) and artificial ageing (30- day water storage and 500 thermocycles) on the occlusal fracture resistance of Turkom- Cera copings were also investigated. There was no influence of the finish line design and artificial ageing used in this study on the occlusal fracture resistance of Turkom- Cera all-ceramic copings (P<0.05). The marginal adaptation of Turkom-Cera copings compared to In-Ceram and Procera copings was assessed. The mean marginal discrepancy for Turkom-Cera, In-Ceram and Procera were 49.2 μm, 71.5 μm and 34.4 μm, respectively. It was verified that there was a statistically significant difference among the marginal discrepancy of the three allceramic systems (p<0.05). In this study, there were no significant differences in the mean marginal discrepancy of Turkom-Cera crowns between the chamfer (49.2 μm) and shoulder (44.0 μm) groups (p>0.05). iv A preliminary prospective study to evaluate the clinical performance of Turkom-Cera crowns was conducted. This study was carried out to complement the different mechanical tests that have been done on the Turkom-Cera all-ceramic material. In this study, 20 Turkom-Cera crowns were evaluated for a mean evaluation period of 21.5 months. During the whole observation period, 1 of the 20 Turkom-Cera crowns was found to have fractured after a service time of 14 months. The veneering porcelain chipped in 3 molar crowns, but did not compromise the integrity of the crowns. The other parameters were rated satisfactory according to the Modified United States Public Health Service (USPHS) criteria. All patients expressed satisfaction with their restorations and did not report any sensitivity during or after treatment

Effect of partial ferrule on fracture resistance of endodontically treated teeth: A meta-analysis of in-vitro studies.

The present meta-analysis aimed to answer the following research question: In endodontically treated teeth (ETT), what is the effect of partial ferrule (PF) on fracture resistance compared to complete ferrule (CF) and/or no ferrule (NF)? PubMed, Scopus, Web of Science, and Google Scholar were searched for relevant studies published until May 20, 2022. In vitro studies that compared the effect of partial ferrule with that of complete ferrule and/or no ferrule on fracture resistance of ETT were included. The studies were assessed for risk of bias, and a meta-analysis was performed. Seventeen in vitro studies comprising 807 teeth were included. Nine studies were at a high risk of bias and eight presented a moderate risk of bias. Overall, the results showed that CF was superior to PF in increasing fracture resistance (SMD= 0.93, CI= 0.57-1.29, P< 0.0001), with no change in the effect based on the type of teeth (P< 0.001). However, the subgroup analysis found that PF 2 mm buccal, lingual, and buccal and lingual ferrule were comparable to CF (P= 0.06). Additionally, the PF group showed significantly higher fracture resistance than the NF group (SMD= 2.02, CI= 1.54-2.49, P< 0.00001). Although CF design provided the highest fracture resistance to restored ETT, PF can still be a viable option for restoring ETT in cases where CF is not feasible

Physical, Optical, and Mechanical Properties of Ceramic Materials after Coffee Immersion and Evaluation of Cleaning Impact with Different Oral Hygiene Tools

This study aimed to evaluate the effect of three oral hygiene tools, a regular toothbrush, an electronic toothbrush, and mouthwash, on the color stability of three different computer-aided design (CAD) and computer-aided manufactured (CAM) ceramic blocks. Feldspathic ceramic (Vita Triluxe Forte), hybrid resin ceramic (Vita Enamic), and lithium disilicate glass-ceramic (IPS e.max CAD) were used in this study. A CAD/CAM system and 81 (27 of each material) samples of ceramic blocks were used. All samples were immersed in black coffee for 15 days, and the coffee was changed twice per day. Using a spectrophotometer probe, samples on a grey background were scanned, and physical properties like surface hardness and depth were measured using interferometry and a 3D non-contact surface metrology. After 30 days of application of oral hygiene tools, instruments were used to measure various physical, mechanical, and optical properties. Vita Triluxe had the highest average color variation values (&Delta;E00) after 15 and 30 days of immersion in coffee in both regular and electronic toothbrushes. Moreover, IPS e.max CAD had the least &Delta;E00 values with no significant differences among the groups. The surface roughness (Ra) of the Vita Enamic ceramic increased when using a regular toothbrush, and the surface height (Rz) for the Vita Enamic ceramic increased when an electronic toothbrush was used. IPS e.max CAD had the greatest modules of elasticity forces, and Vita Triluxe Forte had the lowest when used with a regular toothbrush. The &Delta;E00 values of the tested materials were minimally increased or decreased after 30 days of cleaning, and all were clinically acceptable. Ra and Rz were the highest for Vita Enamic in comparison to the other groups. The highest percentage in IPS e.max CAD was associated with a type 1 fracture, whereas type 3 was predominantly observed with Vita Enamic, and type 2 in the Vita Triluxe group without significant differences

Accuracy of Master Casts Generated Using Conventional and Digital Impression Modalities: Part 1&mdash;The Half-Arch Dimension

Accurate impression-making is considered a vital step in the fabrication of fixed dental prostheses. There is a paucity of studies that compare the casts generated by various impression materials and techniques that are commonly used for the fabrication of provisional and definitive fixed prostheses. The aim of this study is to compare the accuracy of casts obtained using conventional impression and digital impression techniques. Thirty impressions were made for the typodont model (10 impressions each of polyvinyl siloxane, alginate, and alginate alternative materials). Ten digital models were printed from the same model using a TRIOS-3 3Shape intraoral scanner. Accuracy was assessed by measuring four dimensions (horizontal anteroposterior straight, horizontal anteroposterior curved, horizontal cross-arch, and vertical). A one-way ANOVA and Tukey&rsquo;s test (&alpha; = 0.05) were used to analyze data. A statistically significant difference in the four dimensions of the stone casts and digital models was observed among the four groups (exception: between alginate alternative and 2-step putty&ndash;light body impression in the horizontal anteroposterior straight, horizontal anteroposterior curved, and horizontal cross-arch dimensions; between alginate and alginate alternative in the horizontal anteroposterior curved dimension; between alginate and 2-step putty&ndash;light body impression in the horizontal anteroposterior curved dimension; and between alginate alternative and digital in the vertical dimension). Polyvinyl siloxane had the highest accuracy compared to casts obtained from other impression materials and digital impressions

Accuracy of Master Casts Generated Using Conventional and Digital Impression Modalities: Part 1—The Half-Arch Dimension

Accurate impression-making is considered a vital step in the fabrication of fixed dental prostheses. There is a paucity of studies that compare the casts generated by various impression materials and techniques that are commonly used for the fabrication of provisional and definitive fixed prostheses. The aim of this study is to compare the accuracy of casts obtained using conventional impression and digital impression techniques. Thirty impressions were made for the typodont model (10 impressions each of polyvinyl siloxane, alginate, and alginate alternative materials). Ten digital models were printed from the same model using a TRIOS-3 3Shape intraoral scanner. Accuracy was assessed by measuring four dimensions (horizontal anteroposterior straight, horizontal anteroposterior curved, horizontal cross-arch, and vertical). A one-way ANOVA and Tukey’s test (α = 0.05) were used to analyze data. A statistically significant difference in the four dimensions of the stone casts and digital models was observed among the four groups (exception: between alginate alternative and 2-step putty–light body impression in the horizontal anteroposterior straight, horizontal anteroposterior curved, and horizontal cross-arch dimensions; between alginate and alginate alternative in the horizontal anteroposterior curved dimension; between alginate and 2-step putty–light body impression in the horizontal anteroposterior curved dimension; and between alginate alternative and digital in the vertical dimension). Polyvinyl siloxane had the highest accuracy compared to casts obtained from other impression materials and digital impressions

Accuracy of Master Casts Generated Using Conventional and Digital Impression Modalities: Part 2&mdash;The Full Arch Dimension

The aim of this study was to evaluate the accuracy of master casts generated by conventional (putty and light body consistencies polyvinyl siloxane and alginate) and digital impression techniques on a typodont master model with full-arch-prepared abutment teeth. The null hypotheses tested were as follows: (1) no statistically significant differences in accuracy between casts made by the two impression modalities and the typodont master model at each of the four locations (horizontal straight, horizontal curved, horizontal cross arch, and vertical), and (2) no statistically significant differences in dimensions measured at each of the four locations between the casts generated using the conventional and digital impression techniques. For the conventional technique, 10 impressions each were made for the typodont model using polyvinyl siloxane and alginate impression materials, and the casts were poured. For the digital technique, the typodont model was scanned 10 times using a TRIOS-3 3Shape intraoral scanner, and the casts were printed. The measurements for the horizontal (anteroposterior and cross arch) and vertical dimensions were made using a stereomicroscope and the accuracy of fabricated casts was expressed as the percentage of deviation from the typodont master model&rsquo;s values. A one-way ANOVA and Tukey&rsquo;s test (p &lt; 0.05) were used to analyze the data. In the current study, the only measurement that did not exceed 0.5% in dimensional change was with the stone casts produced by both the 3M ESPE PVS and Kromopan alginate impression materials at the HAPC dimension. The casts generated by impressions made using the 3M ESPE PVS impression material were the most accurate, whereas the casts generated by making digital impressions using the TRIOS-3 3Shape intraoral scanner were the least accurate among the three tested groups. The greatest number of distortions above 0.5% (at all dimensional locations) was produced by the digital models printed using the ASIGA 3D printer

Accuracy of Master Casts Generated Using Conventional and Digital Impression Modalities: Part 2—The Full Arch Dimension

The aim of this study was to evaluate the accuracy of master casts generated by conventional (putty and light body consistencies polyvinyl siloxane and alginate) and digital impression techniques on a typodont master model with full-arch-prepared abutment teeth. The null hypotheses tested were as follows: (1) no statistically significant differences in accuracy between casts made by the two impression modalities and the typodont master model at each of the four locations (horizontal straight, horizontal curved, horizontal cross arch, and vertical), and (2) no statistically significant differences in dimensions measured at each of the four locations between the casts generated using the conventional and digital impression techniques. For the conventional technique, 10 impressions each were made for the typodont model using polyvinyl siloxane and alginate impression materials, and the casts were poured. For the digital technique, the typodont model was scanned 10 times using a TRIOS-3 3Shape intraoral scanner, and the casts were printed. The measurements for the horizontal (anteroposterior and cross arch) and vertical dimensions were made using a stereomicroscope and the accuracy of fabricated casts was expressed as the percentage of deviation from the typodont master model’s values. A one-way ANOVA and Tukey’s test (p < 0.05) were used to analyze the data. In the current study, the only measurement that did not exceed 0.5% in dimensional change was with the stone casts produced by both the 3M ESPE PVS and Kromopan alginate impression materials at the HAPC dimension. The casts generated by impressions made using the 3M ESPE PVS impression material were the most accurate, whereas the casts generated by making digital impressions using the TRIOS-3 3Shape intraoral scanner were the least accurate among the three tested groups. The greatest number of distortions above 0.5% (at all dimensional locations) was produced by the digital models printed using the ASIGA 3D printer

The Effect of a Digital Manufacturing Technique, Preparation Taper, and Finish Line Design on the Marginal Fit of Temporary Molar Crowns: An In-Vitro Study

The aim of this study is to investigate the combined effect of a digital manufacturing technique (subtractive vs. additive), preparation taper (10° vs. 20° TOC), and finish line (chamfer vs. shoulder) on the marginal adaptation of temporary crowns following cementation with a compatible temporary cement. Four mandibular first molar typodont teeth were prepared for full coverage crowns with standard 4 mm preparation height as follows: 10° TOC with the chamfer finish line, 10° TOC with the shoulder finish line, 20° TOC with the chamfer finish line and 20° TOC with the shoulder finish line. Each of the four preparation designs were subdivided into two subgroups to receive CAD/CAM milled and 3D-printed crowns (n = 10). A total of 80 temporary crowns (40 CAD/CAM milled and 40 3D-printed) were cemented to their respective die using clear temporary recement in the standard cementation technique. The samples were examined under a stereomicroscope at ×100 magnification following calibration. Linear measurements were performed at seven equidistant points on each axial surface and five equidistant points on each proximal surface. One-way ANOVA analysis and Tukey HSD (Honestly Significance Difference) were performed. The best marginal fit was seen in group 8, while the poorest fit was noted in group 2. Shoulder finish lines and 10° TOC resulted in higher marginal gaps, especially in CAD/CAM milled group. The selection of 3D-printed crowns may provide a better marginal fit within the range of clinical acceptability. Marginal gaps were within clinical acceptability (50 and 120 µm) in all groups except group 2

Biaxial flexural strength of Turkom-Cera core compared to two other all-ceramic systems

Advances in all-ceramic systems have established predictable means of providing metal-free aesthetic and biocompatible materials. These materials must have sufficient strength to be a practical treatment alternative for the fabrication of crowns and fixed partial dentures. OBJECTIVES: The aim of this study was to compare the biaxial flexural strength of three core ceramic materials. MATERIAL AND METHODS: Three groups of 10 disc-shaped specimens (16 mm diameter x 1.2 mm thickness - in accordance with ISO-6872, 1995) were made from the following ceramic materials: Turkom-Cera Fused Alumina [(Turkom-Ceramic (M) Sdn Bhd, Puchong, Selangor, Malaysia)], In-Ceram (Vita Zahnfabrik, Bad Säckingen, Baden-Württemberg, Germany) and Vitadur-N (Vita Zahnfabrik, Bad Säckingen, Baden-Württemberg, Germany), which were sintered according to the manufacturer's recommendations. The specimens were subjected to biaxial flexural strength test in an universal testing machine at a crosshead speed of 0.5 mm/min. The definitive fracture load was recorded for each specimen and the biaxial flexural strength was calculated from an equation in accordance with ISO-6872. RESULTS: The mean biaxial flexural strength values were: Turkom-Cera: 506.8±87.01 MPa, In-Ceram: 347.4±28.83 MPa and Vitadur-N: 128.7±12.72 MPa. The results were analyzed by the Levene's test and Dunnett's T3 post-hoc test (SPSS software V11.5.0 for Windows, SPSS, Chicago, IL, USA ) at a preset significance level of 5% because of unequal group variances (P<0.001). There was statistically significant difference between the three core ceramics (P<0.05). Turkom-Cera showed the highest biaxial flexural strength, followed by In-Ceram and Vitadur-N. CONCLUSIONS: Turkom-Cera core had significantly higher flexural strength than In-Ceram and Vitadur-N ceramic core materials