Patient-Reported Outcomes of Metal and Acrylic Resin Removable Partial Dentures : A Systematic Review and Meta-Analysis

Metal removable partial dentures (RPDs) are often considered long-term treatment options for partially edentulous patients, while acrylic resin RPDs are considered interim treatments. The aim of this review was to compare metal and acrylic resin RPDs regarding patient-reported outcomes for partially edentulous individuals. Four databases (MEDLINE, EMBASE, CENTRAL, and Web of Science) were systematically searched for observational studies and randomized controlled trials comparing patient-reported outcomes between metal and acrylic resin RPDs. The primary outcome was patient satisfaction. Included studies were assessed for risk of bias using the Cochrane risk of bias in nonrandomized studies of interventions tool (ROBINS-I) and the Cochrane Collaboration Risk of Bias Tool for Randomized Controlled Trials. The level of evidence was evaluated using Oxford Center for Evidence-based Medicine tool. A random-effects model was used to analyze the data. A total of 15 studies were included in the systematic review; 10 in the meta-analysis. The pooled effect size for patient satisfaction and oral health-related quality of life showed no statistical significant difference between metal and acrylic resin dentures (0.22, 95% confidence interval -0.01, 0.45, p = 0.06; 1.45, 95% confidence interval -2.43, 5.33, p = 0.46, respectively). Compliance with using RPDs was significantly higher in patients with metal compared to patients with acrylic resin dentures (pooled odds ratio = 0.57, 95% confidence interval 0.45, 0.73, p < 0.001). Most studies had critical to serious risk of bias and low level of evidence. The reviewed studies showed that there was no significant difference between metal and acrylic resin RPDs in patient satisfaction and oral health-related quality of life. Metal dentures were associated with higher patient compliance rates and were preferred more by patients compared to acrylic resin dentures. However, the reviewed studies had low levels of evidence and therefore, high-quality randomized controlled trials are needed to conclusively address the question of this review

IFNβ Protects Neurons from Damage in a Murine Model of HIV-1 Associated Brain Injury.

Infection with human immunodeficiency virus-1 (HIV-1) causes brain injury. Type I interferons (IFNα/β) are critical mediators of any anti-viral immune response and IFNβ has been implicated in the temporary control of lentiviral infection in the brain. Here we show that transgenic mice expressing HIV-1 envelope glycoprotein 120 in their central nervous system (HIVgp120tg) mount a transient IFNβ response and provide evidence that IFNβ confers neuronal protection against HIVgp120 toxicity. In cerebrocortical cell cultures, neuroprotection by IFNβ against gp120 toxicity is dependent on IFNα receptor 1 (IFNAR1) and the β-chemokine CCL4, as IFNAR1 deficiency and neutralizing antibodies against CCL4, respectively, abolish the neuroprotective effects. We find in vivo that IFNβ mRNA is significantly increased in HIVgp120tg brains at 1.5, but not 3 or 6 months of age. However, a four-week intranasal IFNβ treatment of HIVgp120tg mice starting at 3.5 months of age increases expression of CCL4 and concomitantly protects neuronal dendrites and pre-synaptic terminals in cortex and hippocampus from gp120-induced damage. Moreover, in vivo and in vitro data suggests astrocytes are a major source of IFNβ-induced CCL4. Altogether, our results suggest exogenous IFNβ as a neuroprotective factor that has potential to ameliorate in vivo HIVgp120-induced brain injury