An effective route to the additive manufacturing of a mechanically gradient supramolecular polymer nanocomposite structure.

3D Printing techniques are additive methods of fabricating parts directly from computer-aided designs. Whilst the clearest benefit is the realisation of geometrical freedom, multi-material printing allows the introduction of compositional variation and highly tailored product functionality. The paper reports a proof-of-concept additive manufacturing study to deposit a supramolecular polymer and a complementary organic filler to form composites with gradient composition to enable spatial distribution of mechanical properties and functionality by tuning the number of supramolecular interactions. We use a dual-feed extrusion 3D printing process, with feed stocks based on the supramolecular polymer and its organic composite, delivered at ratios predetermined. This allows for production of a graded specimen with varying filler concentration that dictates the mechanical properties. The printed specimen was inspected under dynamic load in a tensile test using digital image correlation to produce full-field deformation maps, which showed clear differences in deformation in regions with varying compositions, corresponding to the designed-in variations. This approach affords a novel method for printing material with graded mechanical properties which are not currently commercially available or easily accessible, however, the method can potentially be directly translated to the generation of biomaterial-based composites featuring gradients of mechanical properties.

Malpractice in treatment of sinonasal disease by otolaryngologists: a review of the past 10 years.

OBJECTIVE: Sinonasal disease is a common condition treated by otolaryngologists. Malpractice in this area is the most common litigation faced by otolaryngologists. This study analyzes malpractice in the treatment of sinonasal disease. STUDY DESIGN: Case series, review of legal records. SETTING: Legal databases. SUBJECTS AND METHODS: Using 2 different computerized legal databases, the phrase medical malpractice was searched with terms related to sinonasal disease involving court cases in the past 10 years (2004-2013), yielding 26 cases. The cases were analyzed for pertinent data regarding plaintiffs, presenting complaint, practice setting, type of malpractice, resulting injury, result of verdict, and amount of reward or settlement. RESULTS: Chronic sinusitis (42%) was the most common presenting symptom. Many cases included multiple types of alleged malpractice, with the most common being negligent technique (38%) and lack of informed consent (27%). The most common alleged injuries included cerebrospinal fluid leak, meningitis, nasal obstruction, and orbital trauma. Defendants prevailed in 13 of 18 cases in which outcomes were known, with mean award of $225,000 and mean settlement of $212,500. The cases won by plaintiffs were all in a private practice setting. CONCLUSION: Otolaryngologists should be aware of the causes of malpractice litigation as it relates to treatment of sinonasal disease. Lack of informed consent continues to be a common allegation, and surgeons should ensure complete informed consent is obtained and well documented. A unified and complete database of medical malpractice cases is needed to allow for further analysis of specialty-related claims.