https://www.um.edu.mt/library/oar/handle/123456789/16120 2026-10-27T08:43:56Z https://www.um.edu.mt/library/oar/handle/123456789/149758 Title: Diagnostic performance of an intraoral scanner for caries detection on permanent tooth surfaces Authors: Agius, Anne-Marie; No-Cortes, Juliana; Cortes, Arthur R. G.; Attard, Nikolai J.; Gatt, Gabriella Abstract: Intraoral scanners with fluorescence technology (IOSFT) include a caries detection feature in addition to their standard scanning function. The aim of this study was to determine the diagnostic performance of the caries detection tool of the IOSFT Trios 4® on permanent premolar and molar surfaces when compared to visual and radiographic International Caries Detection and Assessment System (ICDAS). Methods: Participants (n = 71, age 6–88 years) were examined under standardised conditions using ICDAS criteria for visual caries detection of occlusal and smooth surfaces. Bitewing (BW) radiographs were used to examine proximal surfaces using ICDAS radiographic criteria. Finally, participants underwent an intraoral scan of both the maxilla and the mandible according to the manufacturer’s instructions. The automated caries detection (ACD) output on the IOSFT software was compared to the visual ICDAS scores obtained clinically for occlusal and free smooth (buccal and lingual) surfaces; the IOSFT caries de detection output was compared to radiographic ICDAS scores from BW radiographs for interproximal (mesial and distal) surfaces. Sensitivity, specificity, and accuracy values for each tooth surface were calculated. Results: Out of 3,684 permanent tooth surfaces examined, 461 surfaces with dental caries were included in the analysis. 392 were initial lesions (ICDAS 1–2), while 69 were moderate/severe (ICDAS 3–6). There was a moderate positive correlation (r = 0.4, p < 0.001) when comparing all ICDAS scores to IOSFT ACD categories for unrestored permanent occlusal surfaces. IOSFT ACD accuracy was higher for moderate/advanced lesions (ICDAS 3–6) lesions when compared to initial (ICDAS 1–2) ones (81% vs. 37.7%). For unrestored smooth surfaces, weak positive correlations were found when comparing all ICDAS scores to IOSFT ACD categories (r = 0.19, p < 0.001). Accuracy results for smooth surfaces were 93.5% for moderate/advanced and 77.1% for initial lesions. Correlations between BW ICDAS scores and IOSFT ACD scores for proximal surfaces were weak (r = 0.07, p = 0.019). Diagnostic accuracy was higher for moderate/ advanced lesions when compared to initial ones (83.5% vs. 40.4%). There was a weak correlation between IOSFT ACD categories and ICDAS/visual categories for restored occlusal surfaces (r = 0.029, p = 0.68). Conclusion: IOSFT cannot currently replace visual and radiographic exams for caries detection. 2025-01-01T00:00:00Z https://www.um.edu.mt/library/oar/handle/123456789/149756 Title: Patient acceptance, time efficiency, and inter-operator agreement in intra-oral scanning with fluorescence technology for caries detection Authors: Agius, Anne-Marie; No-Cortes, Juliana; Cortes, Arthur R. G.; Attard, Nikolai J.; Gatt, Gabriella Abstract: Background: Intra-oral scanners (IOS) have been widely used to obtain digital impressions for treatment planning and to enable a full digital workflow on virtual patients. Much less is known about the use of IOS for caries detection. This study focuses on the use of the scanners for caries detection and investigates the number of images, time and patient experiences as well as differences between operators.; Methods: Participants were recruited if they had caries present, their teeth were cleaned using a prophy brush and water and then scanned in a standardised manner. Some participants were scanned a second time by another operator. The automated caries detection results as well as the number of images needed and time taken per jaw scanned was noted. Participants were also asked to complete a questionnaire regarding their experience during the scanning process.; Results: Data sets (scanning time and number of images) from 78 participants were both found to be non-normal using the Shapiro Wilk test (p < 0.001). A Mann-Whitney U test revealed that both the time taken (U = 17772.500, z = -8.066, p < 0.001) as well as the number of images needed (U = 15252.000, z =-9.651, p < 0.0001) were significantly higher for the maxilla when compared to the mandible. The same test also showed that significantly more time (U = 102718.500, z = 14.505, p < 0.0001) and images (U = 108395.500, z = 16.457, p < 0.0001) were needed for scanning permanent teeth when compared to primary teeth. The questionnaire revealed that the vast majority of participants (87%) found the scanning procedure comfortable and acceptable but there were statistically significant differences in discomfort experienced in different areas of the mouth, with the most uncomfortable area scanned being the distal surfaces of the upper molars (p < 0.001). A Wilcoxon Signed Rank test revealed no significance difference in jaw scanning time (z = 0.118, n = 12, p = 0.906) and number of images taken per arch (z = 1.255, n = 12, p = 0.209) between the operators. Cohen’s Weighted Kappa yielded the following significant result: κ = 0.744, p < 0.0001 showing good agreement between the operators’ automated caries detection results. 2025-01-01T00:00:00Z https://www.um.edu.mt/library/oar/handle/123456789/149002 Title: Biological and prosthodontic outcomes of conventional and mini-implants immediately loaded with overdentures : results of a five-year prospective cohort study Authors: Mifsud, David Paul; Attard, Nikolai J. Abstract: Objectives: The aims of this study are to report on an ongoing prospective study evaluating the biological and prosthodontic outcomes of patients treated with immediately loaded mandibular overdentures using two conventional or two mini-implants for up to five years.; Methods: Two groups of edentulous patients with functional complete dentures had the lower prostheses converted into an overdenture using either two conventional (4.0mm) or mini-implants (<3.0mm) using unsplinted attachments (Locators) and followed up. Implant survival, peri-implant bone profile and prosthodontic events were assessed. Statistics to compare between baseline, one and five years and between groups were performed using Mann-Whitney U Test. Chi-square test was used to analyze prosthetic maintenance and complication interventions between groups.; Results: 30 patients were followed–9 deaths were reported (5 in CI group and 4 in MI group). 11 patients were lost to follow-up (4 in CI group and 7 in MI Group). In CI group, 16 patients age (70.8±6.7yrs) and MI group, 14 patients (73.8±7.7yrs) were analysed. The mean observation period was 56.1 months (S.D.±22.48) for CI group and 51.35 months (S.D.±21.12) for the MI group and was equal in both groups (MW Test, p>0.05). Implant success rate was 96.8% in the CI group and 89.3% for MI group (Fisher’s exact test, p=0.34). There was no difference in cumulative survival rates of implants in both groups (Log Rank Mantel-Cox, p=0.65). Mean±S.E. bone loss differences between CI (0.41±0.08mm) & MI (0.81±0.13mm) groups were significant (MW Test, p=0.022). With regards to prosthodontic outcomes, significant differences were observed for fractures of the overdenture and antagonist, and debonding of the matrices (p<0.05).; Conclusion: Bone loss was still significantly higher among the MI group. The two-implant mandibular overdenture required regular maintenance which was significantly higher in the CI group.; Clinical Relevance: Further modifications to the prosthodontic protocol are required to further improve the clinical effectiveness of treatment. 2026-01-01T00:00:00Z https://www.um.edu.mt/library/oar/handle/123456789/148593 Title: Effect of sintering speed of large laboratory furnaces on marginal and internal gaps of CAD-CAM monolithic zirconia crowns Authors: Wilkin, Ewa; Cuschieri, Laura Althea; No-Cortes, Juliana; Cassar, Glenn; Mifsud, David Paul; Cortes, Arthur R. G. Abstract: Purpose: High-speed sintering protocols have been used to expedite the production of zirconia crowns. However, information on the impact of different sintering speeds on the marginal and internal crown adaptation is sparse and only available for chairside systems. The aim of this study was to assess the impact of different sintering speed protocols on Sintering Speed on Marginal and Internal Gaps of CAD-CAM Monolithic Zirconia Crowns. Material and Methods: This in-vitro study was performed on a total of 45 prefabricated standardized resin tooth preparations for study models. Each preparation received a monolithic zirconia crown designed and milled using a high-end computer-aided design and computer-aided manufacturing (CAD-CAM) system. The crowns were divided in 3 groups of 15 crowns each, according to the sintering protocols available in the system of the laboratory furnace used: conventional (8h), fast (3.5h) or ultra-fast sintering (75 min). Marginal and internal gaps of all crowns were assessed using a high-resolution digital microscope. Statistically significant differences among groups were assessed with the one-way ANOVA test. Results: Regarding marginal gap, conventional sintering (37.83 ± 10.41μm) was slightly outperformed by both fast (30.64 ± 9.32μm) and ultra-fast (24.01 ± 5.62μm) groups (p=.003), with a significant pairwise difference between the first and the latter (p=.006). In addition, there were no statistically significant differences among groups for internal gap measurements (p=.393). Conclusion: All three groups obtained satisfactory marginal and internal gap values. However, the present findings suggest that ultra-fast sintering speed protocols lead to smaller marginal gap of CAD-CAM zirconia crowns, as compared to the conventional counterparts. 2025-01-01T00:00:00Z