Dental Radiography Bite Blocks: Positioning, Sizes and Stocking

A retake costs more than a sensor holder. It costs chair time, another dose of radiation for the patient, and a technician's confidence in the technique. Bite blocks and positioning aids exist to remove the guesswork from where the film or sensor sits, and they work well when the practice has a defined set of aids rather than whatever is left in the drawer.

What Positioning Aids Do

Radiographic positioning aids hold the receptor at a defined angle and distance from the tooth. Two approaches dominate: the paralleling technique, where a holder keeps the receptor parallel to the long axis of the tooth and the beam meets it at a right angle, and the bisecting angle technique, where the receptor sits closer to the tooth and the beam angle compensates. Bite blocks and holder assemblies serve the first, and the geometry matters because any tilt produces the classic foreshortened or elongated image that has to be repeated.

Single-Use and Reusable Aids

A disposable bite block in a 100-pack avoids reprocessing entirely: the block goes in the waste after the exposure and the practice keeps a clean supply at each operatory. Reusable holders cost more per unit and require the practice to run them through the reprocessing cycle with the rest of the semi-critical instruments, which is the correct classification for items that contact intact mucosa and are contaminated by saliva. A practice that cannot complete a full reprocessing cycle between patients is better served by single-use aids.

Sizes and Shapes

Adults and children need different block thickness because the occlusal space differs; a paediatric block that is too thick will not seat and a posterior block that is too shallow lets the patient bite through. Most suppliers offer anterior and posterior blocks, and some offer a size range for mixed dentition. Keep at least two sizes at each operatory so a child is not scanned with an adult block and a full-mouth series does not depend on one shape.

Positioning Basics That Reduce Retakes

Roughly, four habits do most of the work. Place the receptor first and ask the patient to close gently, then confirm the block is not pinching the gingiva. Keep the beam perpendicular for paralleling exposures and never let a patient adjust the block after it is set. Use the same technique for every patient in a series so images line up for comparison. Finally, check the positioning of the tube head against the aid rather than against the patient's face, because facial landmarks move.

Infection Control and Radiation Practice

Positioning aids in contact with mucosa are semi-critical items under provincial infection control guidance; single-use versions remove the risk of an incomplete cycle. Radiation practice itself is covered by federal and provincial requirements for dental radiography, including equipment inspection and operator training. The practical point for supply planning is that a bite block is a device used at the point of exposure, so it belongs in the same checklist as the sensor sleeve and the surface barrier rather than in a general consumables drawer.

How Many to Stock

Count exposures and multiply. A practice taking a four-image bitewing series on fifteen patients a week uses sixty blocks a week, or about 250 in a four-week month. That is between two and three 100-packs. A full-mouth series pushes the number higher, and a second operatory doubles it. Keep a pack at each chair, a sealed spare in the storeroom, and a reorder point that reflects the supplier's lead time rather than the shelf, because running out of blocks stops radiography, not just an appointment.

Ordering for a clinic, lab or care home? Wholesale and multi-site ordering covers case pricing and account setup, and the B2B wholesale collection lists the lines stocked for institutional buyers.

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Frequently Asked Questions

Are disposable bite blocks required, or can reusable holders be used?

Both are used in Canadian practices. Reusable holders need a full reprocessing cycle between patients, so they suit practices with established instrument reprocessing. Single-use blocks remove that step and are the simpler choice when the schedule is tight or a locum team works the chair.

How many bite blocks does a dental office use in a month?

Multiply exposures by patients. Fifteen patients a week with a four-image bitewing series uses sixty blocks weekly, roughly 250 a month, which is two to three 100-packs. Add a pack per additional operatory and keep one sealed spare in the storeroom.

Why do bitewing radiographs come out elongated or foreshortened?

Almost always an angle error. In the paralleling technique the receptor must be parallel to the tooth with the beam perpendicular; a tilted block or a tube head aimed at the patient's face rather than the aid produces the distortion. A correctly seated block and a consistent tube head position remove most retakes.

How should bite blocks be stored and disposed of?

Store packs closed, off the floor and away from the sterilising area, and rotate oldest first. Used blocks go into general waste unless visibly contaminated with blood, when they follow the facility's clinical waste stream. Keep the reorder point on the shelf label rather than relying on memory.

Last updated: September 2026. CliniEco Medical is a licensed medical device establishment (MDEL #35334).