Originally published in the November 2015 issue of Veterinary Practice News. Enjoyed this article? Then subscribe today! What comes to mind when you hear that dreaded crack during extraction of a firmly rooted tooth? Do colorful expletives flow from your mouth like water from a faucet? Does your heart sink deeper into your chest? I once felt this way when I broke roots during the process of extracting teeth, but over the past 18 years, I have learned to envision this complication in a different light. I encourage you to think of the breaking of a root not as an insurmountable challenge, but rather as an opportunity to retrieve the remaining root structure without the rest of the bulky tooth being in the way. This outlook is easier to embrace when you’ve learned a relatively foolproof plan to remove stubborn root tips. In this column, I’ll describe my approach. First, let’s discuss the controversial topic of what to do with root tips that are an incidental finding on dental radiographs in an apparently healthy and happy patient. The accessibility of digital dental radiography has provided the ability to diagnose retained root tips that may not be visible on oral examination. These root tips may be present due to incomplete extractions done previously or prior tooth fractures where the gingiva and bone grew over the area of prior tooth trauma. Some veterinary dentists feel that every root tip, even if found incidentally with no evidence of current infection, should be removed in its entirety. One study found radiographic evidence of periapical pathology in 57 percent of retained tooth roots.1 Retained roots also have been implicated in some cases of lymphoplasmacytic rhinitis.2 JOHN LEWIS, VMD, FAVD, DIPL. AVDC A lateral window and moat are created around a root tip to allow for placement of dental elevator. If the root tip breaks again further down, the process may be repeated. Whether a retained tooth root causes problems in the future is likely related to the health of the root at the time of extraction. Some roots can maintain blood supply and remain as a vital, nonpainful portion of the jaw (Figure 1). Since root tips sit adjacent to neurovascular structures, the merits and risks of retrieving quiescent root tips should be weighed in each case. The questions I ask when deciding whether to remove a tooth root that is an incidental finding on radiographs and is buried within gingiva and bone are: Are there radiographic signs of the tooth root being nonvital or infected? These signs may include wide root canal compared to the contralateral tooth or periapical lucency of the bone surrounding the tip of the retained root. Is there clinical evidence of infection or loss of vitality of the root tip? This may include palpable swelling of adjacent bone or soft tissue or a draining tract through the gingiva, mucogingival line, or alveolar mucosa. Is the patient presenting for signs of possible oral pain? If so, I want to remove any possible source of pain, including any incidentally found tooth roots. Is there radiographic evidence of the body converting the root into bone? Root replacement resorption may be seen, and if this is evident on radiographs as a decreased density of the root compared to normal adjacent roots and replacement of the normal periodontal ligament space, it may be reasonable to monitor the site each year with serial radiographs. When a root tip breaks off during an extraction, the first step in its retrieval is obtaining greater exposure. If a pedicle flap has not already been raised, extend releasing incisions far enough apically to allow for full exposure of the bone that contains the root tip. After raising a mucoperiosteal flap, remove bone lateral to the root tip with a small round bur such as a one-quarter or one-half round surgical length carbide bur on a water-cooled high-speed handpiece. The one-quarter size is the smallest size round bur available, which allows for subtle removal of bone lateral to and circumferentially around the tooth root. The small size of the bur is important since root tips are adjacent to neurovascular structures, and if encountered, the smaller bur will cause less damage and less bleeding. Care should be taken when using the one-quarter bur since it may fatigue and the head may detach from the shaft. After a window of bone has been removed from the lateral surface of the root, a thin moat is created circumferentially around the root with the bur to allow for a dental elevator or root tip elevator to be placed into the periodontal ligament space on the lingual/palatal surface of the root.3 With gentle lateral pressure, the root is displaced from its alveolus and delivered through the lateral bone window. JOHN LEWIS, VMD, FAVD, DIPL. AVDC A radiograph of Dr. John R. Lewis’ right mandible shows a retained tooth root of a previously “extracted” wisdom tooth. The tooth root has caused no pain or signs of infection over the past 25 years, probably because the tooth was not endodontically diseased at the time of extraction. Root tip forceps or a small pair of needle drivers may be helpful to grab the root tip once loose. Care should be taken to avoid pushing the root tip into the mandibular canal or the nasal passage, and if this happens, it should be retrieved at that time or referred to a specialist for future removal. This complication can be avoided if forces are generated laterally instead of in the direction of the root apex. Always take a postoperative radiograph to document the root has been removed. What if drilling of the bone window or the moat results in a significant bleeder? Pack the area with a gauze sponge, take a deep breath and apply digital pressure for three minutes. Avoid the temptation to remove the gauze to check the status of the bleeding every 30 seconds. Make a mental note of what area of the moat the bleeding arose from, and avoid using the bur in that area after the bleeding subsides. Hopefully your next root tip retrieval will be easier by using these techniques. Until next time, keep on drilling! Dr. Lewis, VMD, FAVD, Dipl. AVDC, practices veterinary dentistry and oral surgery at NorthStar VETS in Robbinsville, N.J. Columnists’ opinions do not necessarily reflect those of Veterinary Practice News. References Moore JI, Niemiec B. Evaluation of extraction sites for evidence of retained tooth roots and periapical pathology. J Am Anim Hosp Assoc. 2014; 50(2): 77-82. Stepaniuk KS, Gingerich W. Suspect odontogenic infection etiology for canine lymphoplasmacytic rhinitis. J Vet Dent 2015; 32(1): 22-29. Woodward TM. Extraction of fractured tooth roots. J Vet Dent 2006; 23(2): 126-129.
