Aim: To report the application of a novel type of jig that is customized according to each patient to help secure and bond a fixed lingual retainer. Materials and methods: This paper reports the use of a 3D printing pen to fabricate a customized jig using polylactic acid (PLA) filament. The jig is fabricated by ejecting molten PLA over a dental model with an adapted retainer wire on the labial and incisal surface, extending only on the interdental embrasures lingually, thus stabilizing the retainer wire. The lingual or palatal surfaces of the teeth were not covered, allowing for composite resin placement and light-curing for bonding the retainer intraorally. This jig along with the retainer wire was removed and transferred intraorally after bonding preparation. The jig was able to stabilize the retainer wire in position facilitating an easy bonding procedure. Results: A customized jig fabricated using a 3D printing pen was simple to fabricate chair-side, easy to handle, able to stabilize the retainer wire intraorally while bonding, and made the overall process simple and time-efficient. The use of a 3D printing pen is an innovative approach that can be easily performed chair-side. The PLA filament used in the pen is biodegradable and biocompatible, making it an ideal material for medical applications. Conclusion: The clinical procedure for bonding the lingual retainer using the customized jig was found to be very convenient and time-efficient for the clinician and comfortable for the patient. This method can be adopted in clinical practice for bonding lingual retainers for all types of patients and all types of retainer wires. However, this is technique sensitive and its clinical preference for usage may differ from clinician to clinician.