Dental Cartridge Glass Tubes

A dental cartridge, or carpule, is the small glass tube of local anesthetic that loads into a dental syringe. One end is closed by a rubber plunger, the other by a thin rubber diaphragm held under a crimped aluminum cap. In the syringe, the needle pierces the diaphragm and the plunger is pushed forward to deliver the dose.

The format gives the dentist a pre-measured, single-patient dose that loads in seconds, and the Type I borosilicate tube keeps the anesthetic stable over its shelf life.

Cartridge tubes are used for dental local anesthetics such as lidocaine and articaine, filled by anesthetic manufacturers and used with aspirating syringe systems in dental clinics, oral and maxillofacial surgery and veterinary dentistry. Common fill volumes are 1.7 ml and 1.8 ml, with 2.2 ml widely used in Europe; 1.5 ml and 2.0 ml cover other regional and product formats. The same glass barrels also suit other small-volume cartridge applications.

The cartridge is a slim, straight Type I borosilicate tube with a precisely sized bore. The front end has a formed neck that takes the rubber diaphragm and aluminum crimp cap; the rear end is open for the rubber plunger. Bore diameter, wall thickness and length are held to tight tolerances so the plunger seals and glides smoothly and the cartridge fits standard dental syringes. Clear glass allows inspection of the anesthetic before use.

Cartridges are usually siliconized for smooth plunger travel, then filled and sealed aseptically by the anesthetic manufacturer, who qualifies the tube, plunger, diaphragm and cap together as a container-closure system. Clinicians inspect each carpule for cracks, cloudiness or a displaced plunger before loading. Share your fill volume, plunger and diaphragm specifications and we’ll supply tube drawings and samples for fit and filling trials.

We convert Type I borosilicate tubing to precise length, bore and neck geometry, then anneal and inspect the tubes for dimensions and cosmetic defects. Certificates of analysis and glass-type compliance documentation are available on request. We can supply bulk tubes or washed tubes ready for siliconization and sterilization, and we can source matched plungers, diaphragms and crimp caps. Tubes ship in trays to protect the precision ends in transit.