An interesting article titled “Use of Intraoperative Navigation for Minimally Invasive Retrieval of a Broken Dental Needle” appears in the 2015 Journal of Oral and Maxillofacial Surgery and written by Kyle M. Stein (vol. 73, pp. 1911-1916). The article describes retrieving a broken dental needle using a Medtronic StealthStation S7 surgical navigation system.
The use of disposable needles in dentistry has rendered the occurrence of needle breakage an extremely rare event. However, this complication continues to occur, and can be caused by improper technique, inappropriate armamentarium, and unexpected patient movement. I have described a few cases of this occuring on the wisdom teeth complications page at http://www.teethremoval.com/complications.html. In almost every case, needle breakage occurs when an inferior alveolar nerve block is administered with 30-gauge short needles.
In the article a case of a 13 year old female had a broken dental needle located in the right pterygomandibular space. The female had received local anesthesia via an inferior alveolar nerve block using a 30- gauge short (25-mm) dental needle for routine restorative dentistry in the lower right quadrant. She suddenly moved during the procedure causing the breakage. Cone beam computed tomography (CBCT) images were obtained for evaluation.
Given the localized trauma, minimal pain, and expected trismus, the patient was release for a week. A plan for CT-guided surgery was presented using a custom interocclusal splint for repeatable mandibular positioning while allowing for surgical access. Fifteen days after needle breakage, the patient presented at a hospital for surgical check in and had another CBCT taken. The images were sent to a Medtronic StealthStation S7 surgical navigation system.
To perform patient-to-CT data registration, the navigation instrumentation probe was used to trace the reference array, soft tissue landmarks of the face, and hard tissue points, such as the tooth cusps and incisal edges. After data registration was complete, continuous 3D tracking of the navigation probe was available to the surgeon in real time. Using the 3D location of the navigation probe in relation to the needle fragment, a location was chosen to best approximate the most anterior extent of the fragment. A 1-cm incision was made at this site. Using blunt dissection in conjunction with the navigation probe, the needle was located in a few minutes and retrieved with minimal exploration required. The surgery was completed in 15 minutes. The patient successfully recovered.
It should be noted that the The Medtronic StealthStation S7 navigation system was used in an off-label fashion, because it is approved only for use on the skull and midface skeleton as they are stationary. However the use of the splint allowed for the mandible to be held in a fixed position.