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A fundamental step in overcoming this challenge is trying to understand the effects of long-term space travel on the human body. In October 2015, the NASA Office of Inspector General issued a health hazards report related to space exploration, including a human mission to Mars. [9] [10]
Heat and byproducts generated cannot damage the tooth or patient, since the reaction needs to take place while in contact with the tooth during restoration. This ultimately limits the strength of the materials, since harder materials need more energy to manipulate. The type of filling material used has a minor effect on how long they last.
It does not resorb, and is biocompatible, forming a seal against the tooth material that minimizes leakage. [1] Originally, MTA was dark gray in color, but white versions have been on the market since 2002. Bismuth oxide, which was added as a radioopacifier (to make the filling stand out on X-rays), [citation needed] can discolour the teeth. [3]
Cermets, which are essentially metal reinforced, glass ionomer cements, used to aid in restoring tooth loss as a result of decay or cavities to the tooth surfaces near the gingival margin, or the tooth roots, though cermets can be incorporated at other sites on various teeth, depending on the function required. They maintain adhesion to enamel ...
A 2003 study showed that fillings have a finite lifespan: an average of 12.8 years for amalgam and 7.8 years for composite resins. [20] Fillings fail because of changes in the filling, tooth or the bond between them. Secondary cavity formation can also affect the structural integrity the original filling.
Interstellar space is not completely empty; it contains trillions of icy bodies ranging from small asteroids to possible rogue planets. There may be ways to take advantage of these resources for a good part of an interstellar trip, slowly hopping from body to body or setting up waystations along the way. [32]
Local anesthetic injections are given in specific areas of the mouth, rather than the whole body. Although several different medications are available, the most commonly used local anesthetic to prevent pain in the area around a tooth is lidocaine (also called xylocaine or lignocaine). Lidocaine's half-life in the body is about 1.5–2 hours. [2]
In-flight Medical events for U.S. Astronauts during the Space Shuttle Program (STS-1 through STS-89, April 1981 to January 1998) [2] Medical Event or System by ICD9* Category Number Percent of Total Space adaptation syndrome 788 42.2 Nervous system and sense organs 318 17.0 Digestive system 163 8.7 Skin and subcutaneous tissue 151 8.1