79716

Radiation injury to the hematopoietic system occurs when whole body exposure ranges between 200-1000 rads.

74717

The threshold for phosphate excretion in the urine is approximately 0.50 mM, above which phosphate begins to appear in the urine.

43649

1. Infectious hepatitis (Hepatitis A virus): While HAV is resistant to some environmental conditions, it is generally less resistant than HBV.

2. Mumps virus: This is an enveloped virus and is not particularly resistant to environmental factors.

3. Influenza virus: This is also an enveloped virus and is susceptible to heat and many disinfectants.

4. Serum hepatitis (Hepatitis B virus): HBV is known for its resilience. It can survive outside the body for long periods and is resistant to many disinfectants and physical agents, making it one of the more resistant viruses.

45045

Myositis ossificans commonly involves the masseter muscle in the head and neck region. The masseter is the most frequently affected masticatory muscle, often following trauma or injury. This condition involves heterotopic bone and cartilage formation within muscle tissue. Hyoglossus, stylohyoid, and lateral pterygoid muscles are less commonly affected by myositis ossificans.

45650

overtrituration (i.e., triturating for longer than the recommended time) results in a mix that is warm and has a dull surface; often the mix sticks to the capsule; it shortens setting time (because the amalgam mass becomes heated), increases contraction, and increases creep; also increases tensile and compressive strength values (for lathe-cut alloys), decreases tensile and compressive strengths (for spherical alloys); overtrituration by 10% is acceptable

78829

Thromboplastin is essential for prothrombin time, as it is a tissue factor that initiates the coagulation cascade.

88356

Apical endodontic (periradicular) surgery is performed to surgically access the apex of the tooth root and the surrounding periapical tissues. This allows for direct visualization of the area, enabling the clinician to identify the cause of failure of previous root canal treatment (such as a missed canal, a crack, or a foreign body) and perform necessary procedures like apicoectomy (removal of the root tip) and retrofill.

92175

Duraphat (sodium fluoride varnish) typically has a higher fluoride concentration (22,600 ppm) compared to Fluroprotector and APF gels. Casein phosphopeptide (CPP) is a delivery agent, not a fluoride product itself.

91370

The maximum permissible dose of radiation to the operator of an X-ray machine is 5.0 rem per year.

60727

Sialography is a radiographic examination of the salivary glands and their ducts, typically involving the injection of a contrast medium to visualize their structure and detect abnormalities.