Biocompatibility of polylactides in the middle ear: an experimental animal study.

OBJECTIVE: To study the suitability of resorbable polylactides for reconstruction in middle ear surgery. EXPERIMENTAL ANIMALS: Twenty-four chinchillas. INTERVENTIONS: Twenty chinchillas were operated on using 2 types of polylactides inserted into the middle ear and outer ear canal, 10 animals in each group. At 6 months, the animals were killed, and their temporal bones were removed for sectioning. Degree of inflammation, fibrosis, degradation of polylactide material, and new bone formation were assessed histologically. MAIN OUTCOME MEASURES: Polylactide implants caused only a mild local inflammation, with no difference between the 2 materials tested. CONCLUSION: Polylactide acid-based middle ear implants were successfully used in the reconstructive middle ear surgery. Resorption occurred without complications.

Comparison of bacterial adherence to polylactides, silicone, and titanium.

CONCLUSIONS: Less bacterial adherence occurred on uncoated polylactide and silicone than on uncoated titanium surfaces. Albumin coating was an effective method to inhibit bacterial adherence to all these surfaces. As regards bacterial adherence, polylactides are at least as safe implant materials as silicone and titanium. OBJECTIVES: We compared adherence of Staphylococcus aureus and Pseudomonas aeruginosa to four implant materials and studied the inhibitory effect of albumin on adherence. The aims were to discover any differences between materials and to study the effectiveness of albumin coating. MATERIALS AND METHODS: Eight plates of polylactide A and B, silicone, and titanium were exposed to S. aureus and P. aeruginosa. Four of these plates were uncoated and four were coated with albumin. A total of 64 plates were included in the study. The bacteria were stained with acridine orange, and 10 photomicrographs of each plate allowed quantification of the surface area covered with bacteria. RESULTS: The most adherence occurred on titanium without coating. Albumin coating of the surface significantly reduced bacterial adherence to each material. Differences between materials with albumin coating were relatively small. Of the bacteria, P. aeruginosa had the greater capacity to adhere to a surface.

Bacterial adherence to titanium surface coated with human serum albumin.

HYPOTHESIS: An albumin coating on titanium implants will inhibit bacterial adhesion on the implant surface. BACKGROUND: Bacterial, protein, and platelet adhesion on otologic implants and tympanostomy tubes is a major reason for implant sequelae and can eventually lead to implant removal. The role of albumin coating of the implant in prevention of protein adhesion on implant surface has already been tested by the authors. In the present study the authors examined the in vitro adherence of Staphylococcus aureus and Pseudomonas aeruginosa on an albumin-coated and uncoated titanium surface. METHODS: Human serum albumin (HSA)-coated and uncoated titanium surfaces were exposed to viable S. aureus and P. aeruginosa and, after washings, photographed by fluorescence microscopy to quantify the adhered bacteria, which was stained with acridine orange. RESULTS: Bacteria in the suspension adhered at a significantly lesser rate to the coated surfaces than to the uncoated surfaces, with overall bacterial adhesion dependent on bacterial concentration. Binding of S. aureus on HSA-coated surfaces was inhibited significantly (from 82 to 95% depending on concentration). Binding of P. aeruginosa was inhibited from 29 to 37%. CONCLUSION: Because albumin coating can reduce bacterial adherence on titanium surfaces in vitro, reduction is possible in bacterial contamination and infection of the HSA-coated titanium implant in vivo.

Effects of the nasal strip and dilator on nasal breathing--a study with healthy subjects.

OBJECTIVE: To investigate effects of the nose dilating devices on nasal anatomy and breathing in healthy subjects. MATERIALS AND METHODS: 27 healthy subjects were tested when using the Breathe Right nasal strip or the Nozovent dilator. Posterior rhinomanometry, acoustic rhinometry, and a subjective evaluation were used as methods. RESULTS: Both devices significantly increased the minimum cross-sectional area of the nasal valve and decreased nasal resistance. The Nozovent dilator proved to be significantly more effective in reducing nasal resistance than the Breathe Right nasal strip. CONCLUSIONS: Nose dilating devices, the Breathe Right nasal strip and the Nozovent dilator, can be used to reduce nasal resistance. More studies are needed to evaluate the usefulness of the devices for patients with chronic obstruction for any reason in the valve area.