Functionalization of 3D Printed Scaffolds Using Polydopamine and Silver Nanoparticles for Bone-Interfacing Applications.

The prevention of bacterial colonization and the stimulation of osseointegration are two major requirements for bone-interfacing materials to reduce the incidence of complications and promote the restoration of the patient's health. The present investigation developed an effective, two-step functionalization of 3D printed scaffolds intended for bone-interfacing applications using a simple polydopamine (PDA) dip-coating method followed by the formation of silver nanoparticles (AgNPs) after a second coating step in silver nitrate. 3D printed polymeric substrates coated with a ∼20 nm PDA layer and 70 nm diameter AgNPs proved effective in hindering Staphylococcus aureus biofilm formation, with a 3000-8000-fold reduction in the number of bacterial colonies formed. The implementation of porous geometries significantly accelerated osteoblast-like cell growth. Microscopy characterization further elucidated homogeneity, features, and penetration of the coating inside the scaffold. A proof-of-concept coating on titanium substrates attests to the transferability of the method to other materials, broadening the range of applications both in and outside the medical sector. The antibacterial efficiency of the coating is likely to lead to a decrease in the number of bacterial infections developed after surgery in the presence of these coatings on prosthetics, thus translating to a reduction in revision surgeries and improved health outcomes.

Facial nerve palsy with acute otitis media during the first 2 weeks of life.

A full-term male newborn presented to us at the age of 2 weeks with left facial weakness that had started at the age of 4 days and steadily progressed over a 10-day period. Physical examination revealed a complete unilateral left peripheral facial nerve paralysis, with an erythematous dull and bulging left tympanic membrane. Computed tomography and magnetic resonance imaging were normal. The patient underwent left myringotomy and placement of a pneumatic equalization tube within 24 hours of presentation. He also received a 5-day course of prednisone and a 2-week course of antibiotics and acyclovir. Improvement of the facial paralysis was rapid, with near-complete resolution at the time of discharge home and complete resolution 6 weeks later. To our knowledge, this is the only reported case of acute otitis media with associated facial nerve palsy in a newborn during the first 2 weeks of life.