OAR@UM Collection:

The impact of implant macro-design on the implant positional accuracy in static computer-assisted guided implant surgery : an in-vitro study

2025-04-01T07:52:17Z

Title: The impact of implant macro-design on the implant positional accuracy in static computer-assisted guided implant surgery : an in-vitro study Abstract: Aim: The primary aim of this study was to investigate the influence of the implant macro-design on the acquired implant position in static computer-assisted guided implant surgery. The secondary aim was to investigate the influence of tooth/implant position in terms of implant accuracy. A pilot study was also included to gather preliminary data on the influence of macro-design on the acquired implant position in extraction sockets. Method: 25 BLX and 25 BLT Straumann® dummy implants were placed in 10 identical partially dentate typodont models for a total of 50 locations (40 ‘healed’ areas, 10 extraction sockets). A CBCT and intraoral scan were taken for each model. Implant planning was carried out on implant planning software (coDiagnostiX, Dental Wings, Montreal, Canada). BLX and BLT implants were placed equally across all locations. Surgical guides of all models were fabricated with a 3D printer (P40, Straumann®), all having one template fixation pin and mid-palatal mucosal rest. 20 of each implant type were included for the main and secondary analysis (‘healed’ areas), whilst the remaining 5 were used for the pilot study analysis (extraction sockets). Results: No significant differences in implant position were recorded between the two implant types, except at the vertical offset at implant entry (primary objective). No significant differences in implant accuracy were recorded in implant position between tooth-bound spaces (n=20), next to one tooth (n=10) and no proximal teeth (n=10). BLT implants experienced significant deviations in implant angle and apex locations in extraction sockets (pilot study). Conclusion: Implant macro-design is not a significant cofactor in implant positional accuracy. However, BLT implants may be subject to higher implant angles and apex deviations in extraction sockets. Description: M.Sc.(Melit.)

Trueness and adaptation comparison between chairside and laboratory CAD-CAM Zirconia Crowns : an in-vitro study

2025-04-01T07:51:25Z

Title: Trueness and adaptation comparison between chairside and laboratory CAD-CAM Zirconia Crowns : an in-vitro study Abstract: Background: In the presence of tooth structure loss from either carious or non-carious (tooth wear) origin, dental restorative treatment is required to rehabilitate and restore the tooth’s form and function. Restorative treatment can be direct using restorative material, or indirect using dental prostheses fabricated using additive or subtractive methods of manufacturing. These dental prostheses can be temporary or long-term depending on the case and material of choice. Over the years there has been an increase in demand for aesthetic restorations. With superior aesthetics, biocompatibility, and good mechanical properties, zirconia ceramic has become an increasingly popular restorative material for fixed dental prostheses. The fabrication (milling and sintering) of partially sintered monolithic zirconia in a single visit is time-consuming taking up to 12 hours with the conventional laboratory (lab) workflow. With recent advancements, the sintering process can be completed in as little as 15 minutes with high-speed sintering. Regardless of which system the clinician decides to choose, loss of retention and caries are the most common reasons for failure. Both are influenced by the adaptation of the restoration to the prepared surface, expressed as internal and marginal gap measurements. Objectives: The purpose of this in-vitro study is to compare the adaptation and trueness of monolithic zirconia crowns milled using a laboratory workflow (Zirkonzahn, Zirkonzahn GmbH, Gais, Italy) with a chairside workflow (CEREC, Dentsply Sirona). Materials and Methods: A maxillary right second premolar typodont tooth from a mounted prefabricated dental study model was prepared by the CEREC zirconia clinical guidelines with a chamfer finish line. The model’s fully dentate arches with the prepared tooth and bite registration were scanned with an intraoral scanner (Primescan scanner; Dentsply Sirona). A fully anatomical zirconia crown was first designed using the CEREC chairside CAD software with one reference marker on the buccal and lingual aspects. The resulting crown design was exported and used as a reference to create a similar shape and mimic the position of the markers using the scanned arches from the initial scan. The other crown was designed using integrated CAD software (Modellier, Zirkonzahn) for the lab group. Monolithic zirconia crowns were fabricated for both the chairside group (Zirconia+; CEREC, Dentsply Sirona; n=15) and the lab group (Prettau 2; Zirkonzahn GmbH, Gais, Italy; n=15) with the system’s integrated milling and sintering devices (Primemill and SpeedFire, and Zirkonzahn M1 and Zirkonofen Turbo respectively). The internal and marginal gap of each crown was assessed using the triple scan method, scanning the prepared tooth (MS) on a scanning aid, the crown (CS), and the seated scan (SS) after cementation with light-body silicone following timed constant finger pressure. Measurements were taken using 3D software (Zeiss Inspect Optical 3D 2023) on the virtual buccolingual and mesiodistal cross-sectional images. Trueness (3D-deviations between digital wax-up and manufactured crown) of all crowns was evaluated by mesh superimposition of standard tessellation language (STL) files using another software (Geomagic Control X, 3D systems). The root mean squared of the positive and negative deviations of the scanned crown along with a colour map demonstrating these variations were obtained. Statistical analysis was achieved using the Independent Sample t-test for the marginal and internal gap, and the Mann-Whitney U-test for trueness considering that p < 0.05 is significant. Results: Normal distribution was rejected for trueness analysis (p<0.05 with Shapiro-Wilk test) whilst normality was accepted for internal and marginal gap analysis (p>0.05 with Shapiro-Wilk test). The Independent Samples t-test revealed a significant difference in the overall internal and marginal fit between the chairside 81 ± 48.1 μm, 100.7 ± 43.6 μm and lab group 60.9 ± 32.0 μm, 67.8 ± 59.0 μm (p<0.001). No significant difference was found in the axial internal gap (p=0.043). According to the Mann-Whitney U-test the internal trueness of crowns manufactured with the lab workflow was significantly higher (lower deviation) than that of the chairside group with an RMS of 24.2 ± 6.09 μm and 30 ± 7.89 μm respectively (p=0.041). Conclusion: Within the limitations of this in-vitro study, the findings observed herein suggest that both CAD-CAM systems fabricate monolithic zirconia crowns with clinically acceptable cement space and marginal fit. However, the laboratory workflow using the Zirkonzahn software and its respective milling and sintering devices exhibited higher trueness and better marginal and internal fit than the chairside workflow using the CEREC system by Dentsply Sirona. Description: M.Sc.(Melit.)

Self-reported data, oral hygiene and periodontal indices as key performance indicators in a long-term residential care facility for older adults

2025-02-05T07:12:10Z

Title: Self-reported data, oral hygiene and periodontal indices as key performance indicators in a long-term residential care facility for older adults Abstract: Background: In long-term care facilities, optimal oral hygiene is vital for maintaining the overall health and quality of life of older adults. Despite its importance, adherence to oral health guidelines is often inadequate, leading to poor oral hygiene and periodontal health. This research stresses the need to reassess and implement effective oral hygiene Practices by using self-reported data and clinical parameters as Key performance indicators to help implement periodontal care strategies, including guidelines and oral health policies. Integrating feedback from healthcare professionals and older adults is essential to enhance care standards and address the complex oral health needs and quality of life of this growing population effectively. Objectives: The objective of this research study is to assess the effectiveness of oral health indicators as key performance indicators (KPIs) in a long-term care facility for older adults. The aims of the study include exploring the utility of self-reported data, Oral Hygiene Indices, and Periodontal Indices as KPIs within this setting. Additionally, the study seeks to determine if Oral Hygiene and Periodontal Indices effectively reflect the oral self-care management by older adults and/or their carers and if these indices can also serve as tools for monitoring manpower performance in these facilities. Another aim is to examine the impact of oral health education on the outcomes of clinical assessments using these indices. Finally, the study will evaluate whether Oral Hygiene Indices are effective in measuring the impact of poor oral hygiene on the general health and quality of life of older adults. Methods and Materials: In this study conducted at St. Vincent de Paul Long-Term Residential Care Facility for Older Adults, the effectiveness of oral health indicators as key performance indicators (KPIs) was assessed through a cross-sectional and longitudinal clinical design. The study involved both healthcare professionals and older adults residents. The sample included 200 staff members and 384 older adults, determined through Yamane’s Sampling formula to ensure statistical reliability at a 95% confidence level. Calibration and training were provided prior to commencement of the study. The calibration was based on the diagnosis and charting of periodontal disease to standardize data collection, which included various oral health indices. Ethical considerations were meticulously handled, with approvals from various entities, including FREC and UREC, ensuring compliance with GDPR for handling participant data and securing informed consent. Recruitment involved a cross-sectional analysis to gather baseline data on attitudes towards oral health care among different professional groups and residents. Simple random sampling was used to select wards for inclusion, balancing gender representation and cognitive ability among participants. The data collection phased into a longitudinal study, monitoring oral hygiene and periodontal changes over time, and included educational and oral health promotion interventions. [...] Description: Ph.D.(Melit.)

The impact of dental traumatic injuries on the quality of life of adolescents aged 11-14

2024-11-29T09:50:17Z

Title: The impact of dental traumatic injuries on the quality of life of adolescents aged 11-14 Abstract: The aim of this study is to provide insight into how traumatic dental injuries (TDI) impact the quality of life of adolescents aged 11-14, with the goal of aiding dental professionals in improving care and support for this population. The objectives of this study were to: Assess the prevalence and types of dental trauma among adolescents aged 11-14. Evaluate the impact of these injuries on the quality of life of affected adolescents and explore the psychological and social dimensions associated with dental trauma in this age group. Materials and Methods: A cross-sectional study was conducted among adolescents aged 11-14. Data collected through a structured questionnaire that included demographic information, details about the occurrence of dental trauma, and responses to the CPQ 11-14 . The collected data was then analysed to identify patterns and correlations between TDI and quality of life indicators. Results: The findings revealed a 14.74% prevalence rate, aligning with European data. Notably, more females reported TDIs, and a significant portion of injuries occurred at home (56%), particularly during play or falls. Injuries to permanent teeth were associated with worse emotional outcomes, emphasizing the need for early intervention and parental education. The study highlights significant differences between primary and permanent teeth injuries and underscores the importance of preventive strategies. Conclusions: This study concluded that dental trauma does have a significant impact on the quality of life of adolescents, particularly in specific domains related to social and emotional well-being. The findings align with many aspects of the existing literature, they also reveal unique patterns such as having a high prevalence of TDIs that occur at home and emphasize the need for targeted preventive measures and further research. Description: B.Sc. (Hons)(Melit.)