OAR@UM Collection:

The effectiveness of disinfection protocols and different disinfectants on dental impressions submitted to the laboratory.

Thu, 01 May 2014 00:00:00 GMT

Title: The effectiveness of disinfection protocols and different disinfectants on dental impressions submitted to the laboratory. Abstract: Purpose: Disinfection is highly important in dentistry, to avoid cross contamination both between the laboratory and the clinic, and between dental personnel. This study compared the efficacy of disinfection done in the laboratory and clinic together with the different disinfectants used. Materials and Methods: Impressions were taken from each of the 14 participants- 7 using Blueprint 20+ alginate and 7 using Affinis monobody addition silicone. 3 impressions were taken from each participant with 2 week intervals between each one. Every impression was then divided into 3; each part was subjected to spraying MD520, Minuten spray disinfectant or no disinfection (control) respectively. TSA media was used for suspending dilutions and result was found in CFU/cm2 Results: MD520 seemed to be 100% effective with only a few microbial colonies growing below the detection limit, while Minuten turned out to leave higher levels of bacterial growth with the microbial load turning out to be almost twice as much for alginate then polyvinylsiloxane (PVS) impressions. In addition alginate carried significantly more bacteria compared to PVS before subjected to any disinfection. Conclusion: This study showed that unlike disinfection with MD520 some degree of bacterial growth still remains after the use of Minuten; therefore handling of impressions in all settings should be done with care. The use of both disinfectants in combination should also be considered. Description: B.SC.(HONS)DENTAL TECH.

Dental students' compliance to impression disinfection procedures.

Thu, 01 May 2014 00:00:00 GMT

Title: Dental students' compliance to impression disinfection procedures. Abstract: This research study evaluates dental students' compliance to standard protocols with regards to dental impression disinfection at the University of Malta dental teaching clinic and teaching laboratory. Specially designed questionnaires were distributed among dental students, dental technology students and dental hygiene students. The data was analysed and an educational presentation of the infection control procedures was developed. Following the presentation, the questionnaire was then handed out again after one week from the presentation and then after one month. This assessed whether constant reminders are necessary to maintain a good working knowledge of infection control measures. The chi-square test was used for statistical analysis of data. Significance level was set at p<0.05. The response rate was 100%. According to the study. According to the present study 100% of dental students were immunized against Hepatitis B. They were very well aware of the sterilization methods, 85% were of the opinion that autoclave was the best method for sterilization. Examination gloved and facemasks were used by the majority for impression taking. Disinfection of impressions after removal form patient's mouth was practiced by the majority. Resource deficiency, time consuming and loss of precision and dimensional stability of the material was considered to be the reason for not following standard precautions. It was concluded that the knowledge of the students was good and there was increased awareness as far as sterilization and cross infection was concerned but when it comes to practice, it is lacking. Various reasons for not practicing universal precautions were resource deficiency and time consuming Description: B.SC.(HONS)DENTAL TECH.

The effect of survival motor neuron deficiency on motor function in Drosophila

Wed, 01 Jan 2014 00:00:00 GMT

Title: The effect of survival motor neuron deficiency on motor function in Drosophila Abstract: Spinal muscular atrophy (SMA) is a neurodegenerative disease that results from mutations present within the survival of motor neuron (SMN) gene. SMA is caused by a quantitative reduction (not total absence) of SMN protein. In humans, the SMN complex is an essential multi-protein molecule composed of an integral SMN protein, Gemins 2-8 and Unrip, which is crucial for small nuclear ribonucleoproteins (snRNP) assembly. In the present study, the SMN protein was studied using the model organism Drosophila melanogaster. The fly has been successfully used in the study of many neurodegenerative diseases, particularly due to human gene homologues and conserved neuromuscular physiology. With the use of three different SMN mutations, SMA was modelled by creating fly genotypes which were assessed for neuromuscular degeneration. The fly genotypes that were generated were subjected to a battery of behavioural tests which included locomotor and flight ability assays. Neuromuscular dysfunction presenting as flight defects were seen in mutant flies, as well as reduced lifespan. We also tested the role of SMN on adult viability by selectively decreasing expression levels of SMN in different tissues. Our results showed that SMN deprivation within glial cells results in total fly lethality. These findings show that different SMN mutations cause significant effects on motor function and that SMN has both a tissue-specific and ubiquitous role in Drosophila, beginning at even the primal stages of development. Together, these characteristics influence the formation of the SMN complex, its function and allow us to further understand the molecular pathogenesis of SMA. Description: B.SC.(HONS)BIOMED.SCI.

Application of hyperspectral imaging as a tool to assess microbial responses

Wed, 01 Jan 2014 00:00:00 GMT

Title: Application of hyperspectral imaging as a tool to assess microbial responses Abstract: In the last few years, advances in innovative science have provided new technologies to enhance food safety and quality. Sensitive and rapid microbial detection methods are a key solution for the prevention of foodborne diseases. This has a major ripple effect on health and safety world-wide. Standard microbial detection methods such as direct plate counting, immunological methods and methods based on polymerase chain reactions have the main limitations of being time-consuming and labour-intensive. Research in novel and progressive techniques such as hyperspectral imaging enables the development of new microbial detection methods that can overcome the limitations of conventional methods. This study deals with the simultaneous use of hyperspectral imaging and the conventional plate counting method to assess the growth patterns of Escherichia coli NCTC 12900 (sub-type of E. coli 0157) stored at different environmental temperatures. The growth curves and generation times obtained by analysing microbial data shows that E. coli NCTC 12900 grows better at 400C rather than the characteristic optimal temperature of 370C associated with most E. coli 0157 strains. Hyperspectral images of test and control Agar stimulant systems were analysed using Matlab software to obtain separate normalized histograms. The Bhattacharyya distance analysis was then used to obtain plots which show the pattern of microbial growth with time in relation to light absorbance and reflectance detected by the hyperspectral camera. Due to various limitations and confounding variables in the method used in this study to acquire and assess hyperspectral images, correlation between data obtained in the traditional plate counting method and hyperspectral imaging was not possible. Consequently, further research needs to be carried out to better understand the on-line applicability of hyperspectral imaging in quality control measures related to food quality and safety. Description: B.SC.(HONS)BIOMED.SCI.