Saudi Cultural Missions Theses & Dissertations
Permanent URI for this communityhttps://drepo.sdl.edu.sa/handle/20.500.14154/10
Browse
2 results
Search Results
Item Restricted Circadian Patterns of Salivary Flow in Sjogren's Disease(Tufts University, 2024) Alsunni, Mouna; Sankar, Vidya; Singh, Mabi; Finkelman, Matthew; Papas, Athena; Sankar, VidyaAim and Hypothesis: Salivary flow follows a circadian pattern and is influenced by clock genes, which also regulate Aquaporins (AQPs), water channels responsible for salivary flow regulation in salivary glands. A deficiency in AQP5 in mouse salivary glands disrupted this pattern. We hypothesized that patients with Sjögren's Disease (SjD) do not exhibit the same circadian salivary flow pattern as healthy controls. The study compared salivary flow patterns in healthy individuals and SjD patients. To do this, we assessed stimulated whole saliva (SWS) and unstimulated whole saliva (UWS) patterns in SjD subjects compared with healthy controls. Methods: Thirteen subjects per group were required to achieve 80% power. SjD subjects met the ACR/EULAR2016 criteria. During the first visit, participants provided consent. They received instructions for saliva collection at home at two time points (5 AM and 10 AM) for unstimulated whole saliva (UWS, 5 minutes) and stimulated whole saliva (SWS, 2 minutes), with a third sample collected on-site at 3 PM. Friedman's test compared salivary flow within each group across time points, while the Mann-Whitney U test compared salivary flow between groups. Generalized linear mixed models assessed group-time point interactions. Significance was set at α=0.05. Results: The study analyzed 13 healthy controls (10 female, 3 male, mean age 48.9 ± 10.7 years) and 13 SjD subjects (all female, mean age 65.3 ± 8.4 years). In SjD subjects, SWS 0.84 ± 0.83 mL/min, 1.08 ± 1.13 mL/min, and 1.00 ± 1.12 mL/min (p = 0.037) respectively. UWS ranged from 0.17 ± 0.21 mL/min at 5 AM to 0.24 ± 0.22 mL/min at 3 PM (p=0.46). No significant differences in control SWS; p = 0.527, with respective means of 2.80 ± 1.41 mL/min, 3.25 ± 1.81 mL/min, and 2.70 ± 1.42 mL/min. similar results were found in UWS: 1.03 ± 1.24 mL/min at 5 AM, 1.16 ± 1.34 mL/min at 10 AM, and 1.07 ± 1.29 mL/min at 3 PM (p = 0.527). SjD subjects iii had significantly lower UWS and SWS rates than healthy controls (p<0.001). No significant group interactions were observed (p>0.05). Conclusion: The data do not support the hypothesis that SjD subjects have an altered salivary flow pattern compared to healthy controls. Neither SWS nor UWS exhibited a clear circadian pattern in healthy individuals, suggesting a need for further research into circadian influences on salivary flow in the healthy population.12 0Item Restricted Accuracy Assessment of 3D Printed Casts Using Zirconia Fixed Implant prosthesis: A Comparative Study in the Anterior Maxilla(Saudi Digital Library, 2021-06-23) Abdeen, Layal; Papaspyridakos, Panagiotis; Chen, Yo-wei; Kostagianni, Aikaterini; Finkelman, Matthew; Papathanasiou, Aikaterini; Papaspyridakos, PanagiotisObjective: The purpose of the present in-vitro study is to compare the accuracy of 3D printed casts generated from digital implant impressions with one intra-oral scanner (IOS) (Trios 3, 3Shape), from 4 3D printers, with the 3D accuracy of stone casts made by conventional implant impressions, in a partially edentulous anterior maxilla with two implants. Material and Methods: A maxillary cast with a partially edentulous anterior area was fabricated with the placement of two internal connection implants (Regular CrossFit, Straumann®, Switzerland). Stone casts (n=10) that served as a control were fabricated using the splinted open-tray impression technique. A digital impression was taken using a white light IOS (TRIOS, 3Shape), and a Standard Tessellation Language (STL) file was obtained. Four 3D printers were used to print the casts (n=10 from each 3D printer): a Straumann® P30+ (Straumann®, Switzerland) and a Varseo S (Varseo 3D printing system, BEGO®, Germany), which used digital light processing (DLP) technology; a Form 3b+ (Formlabs®, Somerville, MA, USA), which used stereolithography (SLA) technology; and an M2 Carbon (Carbon®, Redwood City, CA, USA), which used Continuous Liquid Interface Production™ (CLIP) technology. The master cast and all models generated from each group were digitized using the same IOS. Accuracy was evaluated digitally and laboratory. The obtained STL files were superimposed on the master cast STL file (reference) to evaluate the 3D accuracy digitally with inspection software (Geomagic Control X; 3D Systems) using the root mean square value (RMS). For prosthesis assessment, an implant screw-retained fixed zirconia prosthesis was fabricated and tested on each cast. Accuracy of fit was assessed using a screw resistance test and radiographic test. Results: The highest median RMS was found in the stone model group (94.6 μm) and the lowest median was in the M2 Carbon group (46.9 μm). The Kruskal-Wallis test revealed a statistically significant difference between the groups (p<0.001). For post-hoc comparisons, Dunn’s test with the Holm-Bonferroni correction resulted in a statistically significant difference in the four tests. The lowest p-value was for the comparison between the M2 Carbon and P30+ groups (p=0.002), with M2 Carbon exhibiting a significantly lower (RMS). The zirconia prosthesis fits adequately on all casts. Conclusion: Within the study’s limitations, the M2 Carbon printer in virtual analysis demonstrated statistically significant lower 3D deviations in root mean square than the Straumann® P30+ printer. Printed casts generated from M2 Carbon, Formlabs® Form 3b and BEGO® Varseo S demonstrated statistically significant lower 3D deviations in root mean square than stone models generated using a conventional implant impression for the present partially edentulous scenario with two implants. Using a screw-resistance test and radiographic assessment, the zirconia prosthesis fit was clinically acceptable on all models.20 0