Search

Purpose: Periprosthetic joint infection (PJI) continues to be a significant complication after total joint arthroplasty. Diagnosis of PJI can be challenging and elusive in the absence of a gold standard. This purpose of this article is to review the current evidence on the utility of serum and synovial fluid biomarkers to help aid in the diagnosis of PJI with focusing on synovial fluid alpha-defensin., Methods: Articles and data for this review were identified by searches of PubMed and Ovid MEDLINE up to June 1, 2016. In addition, we manually reviewed the bibliographies of the retrieved articles for additional citations for references from relevant articles on the diagnosis of PJI., Results: Serum biomarkers can be elevated in various inflammatory conditions. Synovial fluid biomarkers are more accurate for the diagnosis of PJI compared to serum biomarkers. Based on current available data, alpha-defensin is the most promising synovial fluid biomarker for the diagnosis of PJI and is commercially available., Conclusions: Synovial fluid alpha-defensin could enhance our ability to identify PJI and incorporate into the diagnostic algorithm in the future. Large-scale studies are needed to provide more data for its significance for the diagnosis of PJI.

Statement of the Problem: Acetyl resin removable partial denture (RPD) direct retainers may provide an esthetic alternative to conventional metal direct retainers. The effect of repeated stress on acetyl resin direct retainers is unknown., Purpose: This study compared deformation of acetyl resin and metal alloy RPD direct retainers after repeated dislodgments over a test die., Material and Methods: Ten acetyl resin (Thermoflex) and 10 metal alloy (Ticonium Premium 100) RPD direct retainers, fabricated to manufacturers' specifications, were dislodged over a stainless steel die by means of a laboratory test apparatus for a simulated 3-year period (5000 cycles). Occlusal and facial digital images made before and after cycling were measured (mm) for direct retainer deformation by using computer-imaging software (Scion Image 1.62). Student t tests (alpha=.05) were performed for statistical comparisons., Results: A significant difference in deformation between acetyl resin and metal alloy direct retainers occurred in the occlusal view (P=.045), but not in the facial view (P=.832). Average deformation varied but was greatest in the occlusal view: 0.09 +/- 0.8 mm for acetyl resin direct retainers compared with 0.01 +/- 0.9 mm for metal alloy direct retainers. Average facial view deformations revealed no significant differences: 0.039 +/- 0.6 mm for metal alloy and 0.033 +/- 0.7 mm for acetyl resin direct retainers., Conclusion: Within the limitations of this in vitro study, significantly greater deformation resulted with acetyl resin compared with metal alloy direct retainers after 3 years of simulated use.