Directa TrollByte Kimera BIO Endo Sensor Holders · 4305/3105

These are usually sets rather than single parts: most holders are built as a receptor-holding portion plus a right-angle beam aiming rod, with or without an aiming ring. A ring with notches is what brings a rectangular collimator square to the receptor, with the cone perpendicular to the plate. Aiming rods are made at a right angle for the standard projection, and adjustable rods set to 20 or 40 degrees exist for shifting the tube horizontally.

A holder is what keeps the image receptor still in the mouth: the FDA calls it a dental x-ray film holder, a device intended to position and to hold x-ray film inside the mouth, and lists it as Class I (21 CFR 872.1905). A second section covers the dental x-ray exposure alignment device, intended to position x-ray film and to align the examination site with the x-ray beam. The aiming part at the tube end is a position indicating device — a collimator, cone or aperture that aligns the examination site with the beam and restricts the dimensions of the x-ray field by limiting the size of the primary beam.

FDA and ADA guidance names holders that align the receptor precisely with the collimated beam for periapical and bitewing radiographs, and heat-sterilizable or disposable receptor-holding devices for infection control. Using a receptor-holding device reduces the risk of cone-cutting, where part of the receptor is not exposed because the beam is out of line. Published work describes the paralleling technique as producing the most accurate periapical radiographs for endodontic purposes, and notes that a film-holding device used with it standardises the images.

Sources: FDA 21 CFR 872.1905, Dental x-ray film holder · FDA 21 CFR 872.1820, Dental x-ray exposure alignment device · FDA 21 CFR 872.1840, Dental x-ray position indicating device · FDA and ADA: The Selection of Patients for Dental Radiographic Examinations (revised 2012) · Efficacy of a newly designed angulation-adjustable film holder for reducing cone-cutting errors in the horizontal tube-shift technique, 2022 (PMC9668518) · Impact of Rectangular Collimation on Quality of Intraoral Radiographs: Findings from a Clinical Audit at a Dental Practice, 2025 (PMC11988990) · Sampaio-Oliveira et al. 2025, Intraoral digital radiography: a comprehensive report on the technical specifications of current and historical systems (Imaging Sci Dent) · FDA 21 CFR 872.1850, Lead-lined position indicator