Jamal, Hasan; (2021) A novel atraumatic self-bonding and self-healing dental composite to restore carious primary dentition. Doctoral thesis (D.Dent), UCL (University College London).

Preview

Text Jamal_10136353_thesis_sigs_removed.pdf Download (4MB) | Preview

Abstract

Background: Dental caries is considered a widespread global epidemic, affecting an alarming 60 to 90% of minors and adolescents worldwide. Current dental caries treatments pose various consequences on the healthcare system, children and parents. Although several adhesive restorative dental materials are available for dentists to utilise, such as dental composites or glass ionomers, they still demonstrate critical issues such as bulk shrinkage or adhesion failure. These will eventually lead to microleakage, recurrent caries, discolouration, and ultimately failure of the restoration. Moreover, most current materials require rigorous steps, which can be challenging in paediatric restorative dentistry. Thus, the need for a novel restorative option for paediatric patients is required. Here, we propose a novel restorative material with self- bonding and self-healing properties that can be applied in a short time. Two components that aided in this were polylysine (PLS), a food preservative, and mono- calcium phosphate monohydrate (MCPM). / Aims: This research aims to, first, test the ability of the final restorative formulation to form resin-tags on affected-dentine of primary teeth and to quantify the matrix metalloproteinase (MMP) activity at the demineralised dentine surface, in comparison to commercially available restorative materials (Z250, GIC Fuji lX and ACTIVA). / Methods: Tests were performed to determine the ability of the final formulation to form resin tags and compared with the previously mentioned commercial fillings. Carious primary molars were obtained following ethical approval. The final formulation, along with commercially available restorations Renewal MI (SchottlanderTM), 3M ESPE Filtek Z250 with OptiBond Solo Plus adhesive, ACTIVATM KIDS BioACTIVE compomer (PulpDentTM) and GC Fuji IX, GIC, were applied on affected-carious dentine following the manufacturer’s instructions. Samples (n=5 per group) were cross-sectioned and visualised under CLSM to evaluate the resin-tags formation. Moreover, tests were performed to quantify the ability of the final formulation in inhibiting MMP enzymes. 2mm thick sections of coronal dentine fromsound human molars, obtained following ethical approval, were fully demineralised through immersion in 4M formic acid for 48 hours. Following the application of a green fluorescent probe (EnzCheck Collagenase Assay Kit) for 5 minutes, restorative materials were appliedon one surface. Materials included Renewal MI (SchottlanderTM), 3M ESPE Filtek Z250 with OptiBond Solo Plus adhesive, ACTIVATM KIDS Bioactive compomer (PulpDentTM) and GC Fuji IX, GIC according to the manufacturer’s instructions. These commercial restorative materials were chosen, as they are frequently used in paediatric dentistry to restore carious primary teeth. Non- restored dentine was used as a control. Samples were stored in deionised water and incubated at 37oC. Following 1 or 14 days, samples (n=5 per group) were sectioned, and the interface area imaged usingConfocal Light Scanning Microscopy (CLSM). The percentage area of green fluorescence in sections 260*260 micron squared MMP activity was determined through Image J. / Results: For the resin tags, the results demonstrated that the optimised formulation showed long resin-tags infiltration of >200μm long to carious-affected dentine when visualised under confocal light scanning microscopy (CLSM). As for the MMP activity, the results showed that the final formulation had the least fluorescence initially (0.5%), which after 14 days almost totally disappeared. Z250 and ACTIVA’s results were similar after incubation at day 1 (2.5%-2.0%) and day 14 (2.0% 1.8%) respectively. MMP activity of GIC (Fuji lX) was lower than Z250 and ACTIVA on day 1; however, it was higher on day 14, reaching 3.5%. The results were used to support applications to MHRA for clinical trials and a notified body for CE mark. / Conclusion: In conclusion, the research achieved the aim of developing a novel composite restorative material that inhibits the degrading enzymes at the interface and provides good adhesive properties. This makes it a valuable option to restore decayed paediatric patient’s teeth.

Download activity - last month

Export as JSONCSVXML

Download activity - last 12 months

Export as JSONCSVXML

Downloads by country - last 12 months

Export as XMLCSVJSON

Archive Staff Only

View Item