Biomedical subjects
Robert Jagger
Publications and source records attributed to Robert Jagger.
Simple complete denture techniques can provide patient satisfaction.
Explore the source record for details and available documents.
Custom-made mouthguards protect football players.
Explore the source record for details and available documents.
Assessment of the oral health related quality of life of patients awaiting initial prosthetic assessment.
The aim of the study was to quantify the impact of oral health problems on the quality of life of patients who were experiencing difficulties with dentures. Two hundred and ten patients who were awaiting an initial specialist assessment appointment were asked to complete the short form Oral Health Impact Profile (OHIP-14). One hundred and sixty three (78%) questionnaires were completed correctly and were analyzed. Overall, the prevalence of impacts was high in all sub-scales, indicating that denture related problems had a negative impact on quality of life of both partially dentate and elderly patients.
Development of a new poly(dimethylsiloxane) maxillofacial prosthetic material.
Maxillofacial prosthetic materials are used to rehabilitate patients suffering from acquired or congenital facial disfigurement. Silicone rubber materials [poly(dimethylsiloxane) rubbers] are the materials of choice. However, current formulations have inadequate mechanical properties, in particular, tear strength. The purpose of this study was to formulate a new poly(dimethylsiloxane) material with improved mechanical properties in comparison to commercially available materials. The formulations developed were based on condensation chemistry containing a hydroxy-end-blocked poly(dimethylsiloxane), hydrophobic silica filler, silane cross-linking agents, and a tin catalyst. The following parameters were varied in order to formulate improved materials: (a) bimodal polymeric mix (i.e., ratio of high- and low-molecular-weight polymers); (b) silica filler type and quantity. By varying these parameters a formulation was developed with a base polymer mix of 80%:20% high- to low-molecular-weight polymers into which 20% w/w filler was added. This formulation had a tear strength of 22.23 +/- 1.6 m N/mm compared to the commercial materials having tear strengths in the range 4.53-17.63 N/mm.
Analysis of the properties of silicone rubber maxillofacial prosthetic materials.
OBJECTIVES: Maxillofacial prosthetic materials are used to replace facial parts lost through disease or trauma. Silicone rubbers are the materials of choice, however it is widely accepted that these materials do not possess ideal properties. The objective of this study was to assess the properties of a range of commercially available silicone rubber maxillofacial materials and make recommendations for improvements. METHODS: Specimens of five commonly used maxillofacial materials were prepared in dental flasks according manufacturers instructions. Tear strength, tensile strength, percentage elongation, hardness, water absorption and water contact angles were determined for each material. RESULTS: The tear strength of Factor II, Cosmesil HC and Nusil were all comparable and significantly higher than Cosmesil St and Prestige (p<0.001). Nusil had a significantly higher tensile strength and elongation in comparison to the other materials (p<0.001) and Cosmesil St and Cosmesil HC were significantly harder (p<0.001). Factor II was significantly less wetted and Prestige and Cosmsesil St had a significantly higher water absorption in comparison to the other materials. CONCLUSIONS: None of the commercially available silicone rubber materials possessed ideal properties for use as a maxillofacial prosthetic material. Factor II, however, showed more favourable properties due to it's high tear strength, softness and ease of manipulation.
Surface modification of an experimental silicone rubber maxillofacial material to improve wettability.
OBJECTIVES: Good wettability of maxillofacial prosthetic materials is important so that a lubricating layer is formed with supporting tissues thus reducing patient discomfort. The purpose of the study was to surface modify an experimental silicone rubber material in order to improve wettability. METHODS: Samples of experimental silicone rubber were surface modified by first argon plasma treatment followed by chemisorption of ethyleneoxy functional silanes. These were compared with the same silicone rubber which had ethyleneoxy functional surfactants incorporated into the polymer matrix. In all cases contact angles, tear strength and water uptake were measured. RESULTS: Surface modified materials had comparable contact angles to surfactant modified silicone rubber all being significantly lower than the unmodified material. Surface modified materials, however, had a significantly higher tear strength and lower water uptake in comparison to surfactant modified materials. CONCLUSIONS: Argon plasma treatment followed by chemisorption of ethyleneoxy functional silanes proved an effective way of improving the wettability of an experimental silicone rubber maxillofacial prosthetic material without altering bulk properties.