would have been required to provide enough material thickness to mask the discolored teeth. Additionally, in order for the results to be esthetically pleasing, it may have been necessary to place veneers on all teeth in the esthetic zone so the shades and appearance would be consistent. This patient was concerned about loss of tooth structure, so the most conservative treatment option — nightguard bleaching with 10% carbamide peroxide — was selected for both discolored teeth. Nightguard bleaching was also appealing due to its low cost, safety, effectiveness12,13 and simplicity. While internal bleaching can be used for lightening endodontically treated teeth, with the removal of the lingual access restoration, it presents the risk of loss of tooth struc- ture. Furthermore, approximately 7% of internal bleaching cases will develop external resorption defects.14,15 Regardless of the bleaching technique used, a relapse is possible, and is best addressed by external bleaching in a single-tooth tray with 10% carbamide peroxide to rebleach the tooth until it matches the surrounding dentition.16 In summary, discolored teeth can present numerous clinical chal- lenges, ranging from determining etiology to formulating an appropri- ate treatment plan. The patient in this report was offered a conservative resolution to her chief complaint through simple nightguard bleaching. The results were pleasing to the patient, and no tooth structure was sacrificed. In a time in which operative treatment seems to be the default for esthetic dentistry, it is important to remember that more conservative options are often available. D REFERENCES 1. Markley MR. Restorations of silver amalgam. J Am Dent Assoc. 1951;43:133–146. 2. Watts A, Addy M. Tooth discolouration and staining: a review of the literature. Br Dent J. 2001;190:309–316. 3. Schaefer O, Watts DC, Sigusch BW, Kuepper H, Guentsch A. Marginal and internal fit of pressed lithium disilicate partial crowns in vitro: a three-dimensional analysis of accuracy and reproducibility. Dent Mater. 2012;28:320–326. 4. Plotino G, Buono L, Grande NM, Pameijer CH, Somma F. Nonvital tooth bleaching: a review of the literature and clinical procedures. J Endod. 2008;34:394–407. 5. Andreasen JO. Luxation of permanent teeth due to trauma. A clinical and radiographic follow-up study of 189 injured teeth. Scand J Dent Res. 1970;78:273–286. 6. Jacobsen I, Kerekes K. Long-term prognosis of traumatized permanent anterior teeth showing calcifying processes in the pulp cavity. Scand J Dent Res. 1977;85:588–598. 7. Andreasen FM, Zhijie Y, Thomsen BL, Andersen PK. Occurrence of pulp canal obliteration after luxation injuries in the permanent dentition. Endod Dent Traumatol. 1987;3:103–115. 8. Oginni AO, Adekoya-Sofowora CA, Kolawole KA. Evaluation of radiographs, clinical signs and symptoms associated with pulp canal obliteration: an aid to treatment decision. Dent Traumatol. 2009;25:620–625. 9. Delivanis HP, Sauer GJ. Incidence of canal calcification in the orthodontic patient. Am J Orthod. 1982;82:58–61. 10. Popp TW, Artun J, Linge L. Pulpal response to orthodontic tooth movement in adolescents: a radiographic study. Am J Orthod Dentofacial Orthop. 1992;101:228–233. 11. Amir FA, Gutmann JL, Witherspoon DE. Calcific metamorphosis: a challenge in endodontic diagnosis and treatment. Quintessence Int. 2001;32:447–455. 12. Haywood VB. Considerations for vital nightguard tooth belaching with 10% carbamide peroxide after nearly 20 years of proven use. Inside Dentistry. 2006;2:2–5. 13. Ritter AV, Leonard RH Jr, St Georges AJ, Caplan DJ, Haywood VB. Safety and stability of nightguard vital bleaching: 9 to 12 years post-treatment. J Esthet Restor Dent. 2002;14:275–285. 14. Schwartz RS, Summitt JB, Robbins JW. Fundamentals of Operative Dentistry: A Contemporary Approach. Chicago, Ill: Quintessence Publishing; 1996. 15. Todd M, Brackett W, Romero M. Correction of a single discolored anterior tooth due to internal resorption: a clinical report. Compend Contin Educ Dent. 2017;38:e13–e16. 16. Haywood VB, DiAngelis AJ. Bleaching the single dark tooth. Inside Dentistry. 2010;6:42–52. You have questions. OSAP has the answers. Dental safety is serious business. That’s why we focus on prevention and control. OSAP is a recognized resource for checklists, training programs and effective protocols to keep your patients and the entire dental team safe. Members also get answers to the small and large infection control challenges that occur during care delivery. Visit OSAP.org and join today. DecisionsInDentistry.com December 2017 • Decisions IN DENTISTRY 25
