RADT W2 Ch 4, Ch 7, Ch 21: Rad Protection, Xray Equipment, Bitewing Tech

Define: Inheremt Filtration

Takes place when the primary beam passes through glass window, oil bath abnd tube head seal of the xray unit,

*built into the machine already

Define: Added filtration

Aluminum discs in the path of the xray beam between the collimator and tube head seal in the xray unit.

• Filters out LONG wavelengths with low energy and soft radiation

What is the filtration range?

1.5mm BELOW 70 kvP and 2.5 ABOVE 70 kvP

What is the recommended PID/Cone shape to reduce patient exposure?

Long, rectangular PID since less divergence of xray beams therefore it is the most effective.

What type of xrays do not require a thyroid collar?

extra-oral radiography

What is insight film? Whats another name for it ?

Aka F-speed film

It is the fastest intraoral film (phosphorus film). It can provide 20% reduction in exposure to patients over E-speed films

What is a dosimeter?

X-ray exposure monitoring device that can be used by radiographers in the workplace

What is the maximum permissible dose (MPD) for persons who work with radiation?

5 rem/yr or 0.05 mSv/year

Rem = unit of radiation dosage

Sv = unit of ionizing radiation dosage

What is the maximum permissible dose for non-occupationally exposed persons and OCCUPATIONALLY exposed PREGNANT women?

0.1 rem/yr or 0.001 mSv/year

Rem = unit of radiation dosage

Sv = unit of ionizing radiation dosage

What does maximum accumulated dose mean? What is MAD determined by?

Occupationally exposed workers must not exceed the accumulated lifetime dose.

Determined by age

What does ALARA stand for?

As low as reasonably achievable. - Philosophy for basic radiation protection concept

What is Code 30?

Safety Code 30 (of the HARP act) pertains to the radiation protection in Dentistry. Provides specific guidance for safety procedures and equipment performance.

What is a Stabe Bite-Block?

Disposable styrofoam bite-block

What is a Uni-Bite/Uni-Grip?

Universal film holder that can be used with bitewing or paralleling technique

What film holding equipment is used in the Bisecting Technique?

Snap-A-Ray aka Eezee-grip

What is another name for Bitewing Technique?

Interproximal Technique

What film size is used for primary posterior dentition?

Size 0

Size 1 film is used for …?

• Mixed dentition for children

• Anterior permanent dentition (Anterior PA -canine)

  • Posterior region for children

Size 2 film is used for…?

• Permanent dentition

• Posterior region placed horizontally and vertically (bitewing)

  • Most common

What is Size 3 films used for?

• Permanent dentition

• Film is longer and narrower in design, so only recommended for bite-wings

• Can expose molar and premolar contact areas in one film

When the PID is positioned ABOVE the occlusal plane the central ray is …. and the vertical angulation is …?

Central ray is directed DOWN

VA is positive

When the PID is positioned BELOW the occlusal plane the central ray is …. and the vertical angulation is …?

Central ray is directed UP

VA is negative

Incorrect vertical angulation in a bite-wing exposure results in…?

Distorted images where occlusal surfaces of maxillary teeth are evident and apical regions of the mandibular teeth are seen

What size films can be used for vertical bite wings?

size 1 or 2

1 for anterior 2 for posterior

What are vertical bite wings taken for?

Used to examine the level of alveolar bone; patients with periodontitis

How do you take bite-wing xrays of edentulous areas (areas with no teeth)?

Use cotton rolls are placed in the areas of the missing tooth/teeth to stabilize the film.

If a patient has tori/bony growths, where should the films be placed?

Between the tori and the tongue, not ON the tori. Can use gauze to cushion floor of the mouth or use the tongue to cushon the film.