1.Fracture resistance of CAD-CAM all-ceramic surveyed crowns with different occlusal rest seat designs
Saurabh CHATURVEDI ; Turki ALQAHTANI ; Saleh ALSOLAMI ; Abdulbari ALQAHTANI ; Gotam DAS ; Ebrahim ALSUBAIY
The Journal of Advanced Prosthodontics 2021;13(1):36-45
Purpose:
To investigate the fracture resistance of monolithic CAD-CAM allceramic surveyed crowns with two different occlusal rest seat designs.
Materials and Methods:
Two maxillary first premolar were prepared for all-ceramic surveyed crowns with wide (2/3 rd of buccolingual width of an unprepared tooth) or narrow (1/3rd of buccolingual width of an unprepared tooth) disto-occlusal rest seat (ORS) designs. Eighty monolithic CAD-CAM all-ceramic surveyed crowns were prepared and divided into 4 groups - Group CR, Composite resin material as a control; Group LDS, Lithium disilicate based material; Group ZIPS, zirconiamaterial (IPS ZirCAD); and Group ZLHT, zirconia- material (CeramillZolidht+).Crowns were cemented on an epoxy resin die with adhesive resin cement. The fracture resistance of crowns was tested with the universal machine. Univariate regression analysis was used.
Results:
The mean ± standard deviation of maximum failure force values varied from 3476.10 ± 285.97 N for the narrow ORS subgroup of group ZIPS to 687.89 ± 167.63 N for the wide ORS subgroup of group CR. The mean ± standard deviation of maximum force was 1075 ± 77.0 N for group CR, 1309.3 ± 283.9 N for group LDS, 3476.1 ± 285.97 N for group ZIPS, and 2666.7 ± 228.21 N for group ZLHT, with narrow occlusal rest seat design. The results of the intergroup comparison showed significant differences in fracture strength with various material groups and occlusal rest seat designs (P<.001).
Conclusion
The zirconia-based all-ceramic surveyed crowns fractured at more than double the load of Lithium disilicate based crowns. The crowns with narrow base occlusal rest seat design had statistically significantly higher fracture resistance than surveyed crowns with wide occlusal rest seat design. The use of narrow occlusal rest seat design in CAD-CAM all ceramic surveyed crowns provides higher fracture resistance, and therefore narrow occlusal rest design can be used for providing esthetics with high strength
2.The Role of Endoscopic Ultrasound in Hepatology
Saleh A. ALQAHTANI ; Floriane AUSLOOS ; Ji Seok PARK ; Sunguk JANG
Gut and Liver 2023;17(2):204-216
Endoscopic ultrasound (EUS) has been an indispensable and widely used diagnostic tool in several medical fields, including gastroenterology, cardiology, and urology, due to its diverse therapeutic and diagnostic applications. Many studies show that it is effective and safe in patients with liver conditions where conventional endoscopy or cross-sectional imaging are inefficient or when surgical interventions pose high risks. In this article, we present a review of the current literature for the different diagnostic and therapeutic applications of EUS in liver diseases and their complications and discuss the potential future application of artificial intelligence analysis of EUS.
3. Response surface methodology-based optimization of ultrasound-assisted extraction of β-sitosterol and lupeol from astragalus atropilosus (roots) and validation by HPTLC method
Perwez ALAM ; Nasir A. SIDDIQUI ; Ali S. ALQAHTANI ; Omer A. BASUDAN ; Saleh I. ALQASOUMI ; Abdullah A. AL-MISHARI ; Anzarul HAQUE
Asian Pacific Journal of Tropical Biomedicine 2020;10(6):281-292
Objective: To optimize the ultrasonication method for efficient extraction of P-sitosterol and lupeol from the roots of Astragalus atropilosus using Box-Behnken design of response surface methodology (RSM), and its validation by high performance thin layer chromatography (HPTLC) method. Methods: Ultrasonication method was used to extract β-sitosterol and lupeol from Astragalus atropilosus (roots). RSM was used to optimize the different extraction parameters viz. liquid to solid ratio (10-14 mL/g), temperature (60-80 °C) and time (40-60 min) to maximize the yield of β-sitosterol and lupeol. The quantitative estimation of β-sitosterol and lupeol was done in chloroform extract of Astragalus atropilosus by validated HPTLC method on 10 cm × 20 cm glass-backed silica gel 60F