Paravina RD, Westland S, Imai FH, Kimura M, Powers JM Evaluation of blending effect of composites related to restoration size. Dent Mater. 2006 Apr;22(4):299-307. doi: 10.1016/j.dental.2005.04.022. Epub 2005 Aug 8.
Paravina RD, Westland S, Kimura M, Powers JM, Imai FH Color interaction of dental materials: blending effect of layered composites. Dent Mater. 2006 Oct;22(10):903-8. doi: 10.1016/j.dental.2005.11.018. Epub 2005 Dec 27.
Pereira Sanchez N, Powers JM, Paravina RD Instrumental and visual evaluation of the color adjustment potential of resin composites. J Esthet Restor Dent. 2019 Sep;31(5):465-470. doi: 10.1111/jerd.12488. Epub 2019 May 16.
Tanaka A, Nakajima M, Seki N, Foxton RM, Tagami J The effect of tooth age on colour adjustment potential of resin composite restorations. J Dent. 2015 Feb;43(2):253-60. doi: 10.1016/j.jdent.2014.09.007. Epub 2014 Sep 19.
Evaluation of Shade Matching Capacity of a Single-shade Contemporary Resin Composite in Anterior Restorations
Interventional studies are often prospective and are specifically tailored to evaluate direct impacts of treatment or preventive measures on disease.
Observational studies are often retrospective and are used to assess potential causation in exposure-outcome relationships and therefore influence preventive methods.
Expanded access is a means by which manufacturers make investigational new drugs available, under certain circumstances, to treat a patient(s) with a serious disease or condition who cannot participate in a controlled clinical trial.
Clinical trials are conducted in a series of steps, called phases - each phase is designed to answer a separate research question.
Phase 1: Researchers test a new drug or treatment in a small group of people for the first time to evaluate its safety, determine a safe dosage range, and identify side effects.
Phase 2: The drug or treatment is given to a larger group of people to see if it is effective and to further evaluate its safety.
Phase 3: The drug or treatment is given to large groups of people to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely.
Phase 4: Studies are done after the drug or treatment has been marketed to gather information on the drug's effect in various populations and any side effects associated with long-term use.
