- Email: [email protected]
Displacement of an impacted maxillary canine root fragment into the nasolacrimal duct: A diagnostic dilemma
G Model JOMSMP-333; No. of Pages 4
ARTICLE IN PRESS Journal of Oral and Maxillofacial Surgery, Medicine, and Pathology xxx (2014) xxx–xxx
Contents lists available at ScienceDirect
Journal of Oral and Maxillofacial Surgery, Medicine, and Pathology journal homepage: www.elsevier.com/locate/jomsmp
Case Report
Displacement of an impacted maxillary canine root fragment into the nasolacrimal duct: A diagnostic dilemma Pasupen Kosalagood a , Pornkawee Charoenlarp a,∗ , Soontra Panmekiate a , Somchai Sessirisombat b a
Department of Radiology, Faculty of Dentistry, Chulalongkorn University, Henry Dunant Road, Pathumwan District, Bangkok 10330, Thailand Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Chulalongkorn University, Henry Dunant Road, Pathumwan District, Bangkok 10330, Thailand b
a r t i c l e
i n f o
Article history: Received 3 September 2013 Received in revised form 19 September 2014 Accepted 6 October 2014 Available online xxx Keywords: Impacted canine Nasolacrimal duct Surgical complication Localization Cone beam CT
a b s t r a c t Maxillary canines are the second most common impacted teeth after third molars. The surgical removal of impacted canines should be carefully considered in order to avoid intra- and post-operative complications. To reduce the chance of unwanted consequences, a thorough and careful diagnostic process including sufficient radiographic examination must be performed. Conventional radiographic techniques are commonly used for localization. However, advanced 3D imaging should be done in cases where 2D radiographs cannot provide sufficient information regarding the position of an impacted canine and its relationship with surrounding structures to minimize surgical complications. Here, we reported a rare case, in which an impacted canine root fragment was displaced into the adjacent nasolacrimal duct. This situation leads to partial duct obstruction. Through discussion of this case, we drew attention to a few subtle features of 2D radiographs showing the need and rationale for advanced imaging modalities such as CBCT as supplementary options. © 2014 Asian AOMS, ASOMP, JSOP, JSOMS, JSOM, and JAMI. Published by Elsevier Ltd. All rights reserved.夽
1. Introduction Impacted teeth are teeth which do not have enough space for eruption into the oral cavity. Commonly, their eruption paths are blocked by other structures. Impacted teeth can cause detrimental effects including damage to nearby teeth and are sometimes associated with cysts or tumors. The prevalence of impacted maxillary canines is reported to be 0.9–3% [1–5], which is second only to mandibular third molars [6,7]. Impacted maxillary canines occur twice as often in females than in males and have a high familial association. The incidence of impacted maxillary canines in Caucasians is fivefold that of Asians [8,9]. Eighty-five percent of impacted permanent maxillary canine crowns are palatal in position, while the remaining are in labial aspect [10–12]. Management of impacted maxillary canines includes orthodontic treatment with or without surgical treatment, which requires accurate diagnosis
夽 Asian AOMS: Asian Association of Oral and Maxillofacial Surgeons; ASOMP: Asian Society of Oral and Maxillofacial Pathology; JSOP: Japanese Society of Oral Pathology; JSOMS: Japanese Society of Oral and Maxillofacial Surgeons; JSOM: Japanese Society of Oral Medicine; JAMI: Japanese Academy of Maxillofacial Implants. ∗ Corresponding author. Tel.: +66 2 218 8714/5; fax: +66 2 218 8715. E-mail address: kiwi [email protected] (P. Charoenlarp).
and precise determination of the location, inclination, and longitudinal axis of the impacted canine in relation to surrounding structures [13,14]. Several conventional radiographic techniques are used during treatment planning of impacted teeth, including periapical, topographic or cross-sectional occlusal, panoramic, and cephalometric radiographs or a combination of these views using parallax or right angle techniques [15]. However, it is often difficult to distinguish minute details and to accurately define anatomical relationships [1]. Therefore, limited field of view (FOV) 3D imaging could be considered as an alternative for particular cases that demand detailed information regarding neighboring structures (i.e. relative inclination of the impacted tooth, adjacent root resorption or thickness of overlying bone) in order to reduce possible surgical or non-surgical complications and to increase value in treatment planning for a more predictable outcome. Several potential consequences may arise during the removal process of impacted maxillary canines such as injury to adjacent teeth, fractured roots, and perforation into nasal cavity or maxillary sinus with or without displacement of the root fragment. The latter one may subsequently lead to secondary acquired lacrimal drainage obstruction. The nasolacrimal duct is a structure which carries tears from the lacrimal sac into the nasal cavity through its superior intraosseous and inferior membranous portions. The anatomy of
http://dx.doi.org/10.1016/j.ajoms.2014.10.001 2212-5558/© 2014 Asian AOMS, ASOMP, JSOP, JSOMS, JSOM, and JAMI. Published by Elsevier Ltd. All rights reserved.夽
Please cite this article in press as: Kosalagood P, et al. Displacement of an impacted maxillary canine root fragment into the nasolacrimal duct: A diagnostic dilemma. J Oral Maxillofac Surg Med Pathol (2014), http://dx.doi.org/10.1016/j.ajoms.2014.10.001
G Model JOMSMP-333; No. of Pages 4
ARTICLE IN PRESS P. Kosalagood et al. / Journal of Oral and Maxillofacial Surgery, Medicine, and Pathology xxx (2014) xxx–xxx
2
the root, but the root fragment could not be found within the sinus. Consequently, a cone-beam computed tomography (CBCT) examination was ordered to re-evaluate the exact location of the root fragment. On the CBCT scan, the 4.88 mm in its largest diameter root fragment was shown in the superior portion of the right nasolacrimal duct near the orbital floor (Fig. 3). The bone perforations at the lateral wall of the right nasal cavity and the medial wall of the right maxillary sinus were 5.00 and 2.42 mm in size, respectively (Fig. 4). Because of these findings, the patient was referred to an ophthalmologist for proper management of possible secondary acquired lacrimal drainage obstruction. 3. Discussion
Fig. 1. The anatomy of the nasolacrimal duct.
the nasolacrimal duct is shown in Fig. 1. The intraosseous portion of the duct starts from the medial aspect of the eyes and travels posterolaterally along the lateral nasal wall, while the 5-mm long membranous or meatal part runs beneath the nasal mucosa [16–19]. Eventually, the canal opens into the inferior meatus under the inferior nasal turbinate through a pin-point, triangular or slitlike opening known as the valve of Hasner [20]. The reported mean length of the intraosseous part is 11.2 ± 2.6 mm (range: 6–21 mm), and its average diameter is 3.7 ± 0.7 mm (range: 2–7 mm) [21]. The size of the canal varies with patient’s age, sex and race [16]. Its diameter is larger in males than females and increases in size with age [17,18]. There is also a geographic variability, as Pacific people are shown to have wider canals than Caucasian or New Zealand Maori [17]. The possibility of any foreign body entering the nasolacrimal duct is minimal. In this report, a rare case of surgical complication in which the canine root fragment was displaced into the nasolacrimal duct, potentially leading to partial obstruction of the duct, is reviewed. Through discussion of the case, we drew attention to a few subtle features of 2D radiographs showing the need for advanced imaging modalities such as CBCT as a supplementary option to avoid such problems. 2. Case report A 21-year-old female was referred from an orthodontist to the Oral and Maxillofacial Surgery Clinic at the Faculty of Dentistry, Chulalongkorn University for surgical removal of an impacted right permanent maxillary canine. An original panoramic radiograph was available at the time, but was missing during preparation of the current publication. It was reported to have an impacted canine with the crown located between the roots of lateral incisor and first premolar, and the root positioned high in the inverted Y region. The patient underwent surgical removal of this tooth under local anesthesia. A full mucoperiosteal flap was reflected, and the labial cortex covering the crown of the impacted canine was removed before elevating the canine. During this procedure, the apical one-third of the root fractured and was retained in the site. An attempt to remove the root fragment failed, and the root fragment disappeared. A postoperative panoramic radiograph (Fig. 2) was taken three days later, and the root fragment was detected at the supero-medial region of the right maxillary sinus at the level of the middle/inferior concha. A Waters’ radiograph was then prescribed, but the location of the root fragment cannot be clearly identified. After the surgeon’s initial interpretation, a Caldwell–Luc operation was attempted to retrieve
The development of the maxillary canine begins within a complicated area of facial bones, surrounded by the orbit, the nasal cavity and maxillary sinus [22]. If impaction occurs, the canine’s root can be found deep in the maxilla among those structures. In addition, the prevalence of dilacerated roots is common – reported to be 26–57% [23,24], while few studies described post-operative nasal wall perforation as a complication due to root apex proximity or intra-operative surgical procedure [25,26]. Hence, surgical removal of impacted maxillary canine should be carefully considered to avoid intra- and post-operative complications. In order to achieve this goal, precise tooth localization is crucial. In more than 60% of cases, it is possible to decide whether the crown of the impacted tooth is facial or palatal using palpation [27]. In other cases, radiographic assessment is needed for effective localization [15]. A conventional two-dimensional (2D) radiograph is commonly acquired to investigate location of the impaction. Panoramic radiography is usually prescribed to determine angulation, mesio-distal position, depth of impaction, and the relationship with adjacent structures. However, diagnosis and treatment planning based on 2D imaging is difficult and prone to misinterpretation due to structural superimposition, image magnification and image distortion. Three-dimensional modalities not only offer precise location of impacted maxillary canines, but also show root configuration and dimension, associated pathologies, root proximity and availability of surrounding bone, allowing for proper treatment planning [28,29]. Moreover, if any complication occurs, detailed information of structures in complex anatomical areas can be properly visualized, including bone perforations, location and size of fractured parts and their distance to surrounding landmarks. In our case, the root fragment, dislocated into the nasolacrimal duct, was not immediately recognized from conventional radiographs. Despite the fact that the post-operative panoramic radiograph (Fig. 2) revealed the root of interest within the sinus outline at the mid-sinus level closing to the antero-medial antral wall, it was in an unusual location within the sinus considering the force
Fig. 2. Panoramic radiograph showing the root fragment (arrow) by the medial wall of the right maxillary sinus.
Please cite this article in press as: Kosalagood P, et al. Displacement of an impacted maxillary canine root fragment into the nasolacrimal duct: A diagnostic dilemma. J Oral Maxillofac Surg Med Pathol (2014), http://dx.doi.org/10.1016/j.ajoms.2014.10.001
G Model JOMSMP-333; No. of Pages 4
ARTICLE IN PRESS P. Kosalagood et al. / Journal of Oral and Maxillofacial Surgery, Medicine, and Pathology xxx (2014) xxx–xxx
3
Fig. 3. Multiplanar reconstructed images comprising axial (A), coronal (B) and sagittal (C) views. The white arrows in the images point to the root fragment in the nasolacrimal canal.
of gravity and the anatomy of the maxillary sinus. Inside an empty cavity, any foreign object should always fall downward in accordance with the head’s position unless the following exceptions are present. First, it might be trapped by partial septation. Second, any inflammation process might roughen and thicken sinus mucosa resulting in suspension of the root piece. In addition, the principle of panoramic image acquisition, in which the middle portion of the nasal cavity superimposes on the maxillary sinus, should be kept in mind [30]. Therefore, the object of interest in our case could situate inside either the nasal or the antral cavities. An additional right angle image, a Waters’ view in this case, was also prescribed but no extra information was provided. With the above-mentioned 2D radiographic finding, advanced 3D imaging should be considered as the modality of choice to obtain more details in order to avoid unexpected complications for cases similar to the one reported here. It should be emphasized that 2D radiographic views are not always able to illustrate the exact location of the root fragment, particularly in the naso-antral complex. The chance that a root fragment is pushed into the nasolacrimal duct is very rare owing to several factors: (1) position, angulation and relationship between impacted root and nasolacrimal duct, (2) distance between root fragment and the opening of nasolacrimal duct, (3) diameters of root fragment compared to Hasner’s valve, (4) types of membranous valve openings and (5) intra- and postoperative force and direction of action. From the literature review, there is no report concerning the first three factors. Regarding the membranous opening, a high incidence of pin-point (33%) and
slit-like (40%) openings with very small diameters compared to triangular types has been reported [21]. In the presented case, the root fragment went through this constricted barrier and was displayed in the superior part of nasolacrimal duct. The size of this root fragment (maximum diameter: 4.88 mm) was slightly less than the perforated lateral nasal wall (5.00 mm). Combined with the fact that the shortest migratory path distance from the perforation of the lateral nasal wall to the opening of the intraosseous part of the nasolacrimal duct was 10.83 mm, it can be speculated that the root fragment was pushed through the lateral wall of the nasal cavity and eventually into the membranous and intraosseous part of the nasolacrimal duct. Secondary acquired lacrimal drainage obstruction may result from a variety of infectious, neoplastic, inflammatory, traumatic, or mechanical causes as well as from unusual dental origins [31–33]. Few cases of dentigerous cysts have been reported to cause obstruction to the lacrimal drainage system [34–36], while two cases of ectopic teeth compressing the nasolacrimal ducts have also been described [37]. The symptoms of nasolacrimal ducts obstruction commonly presents with epiphora and acute or chronic dacryocystitis [37], and required complex treatment as endoscopic dacryocystorhinostomy (DCR). Despite its low incidence, this kind of complication is not worth the risk. The authors propose that CBCT examination should be considered pre-operatively in case the initial evaluation indicates vertical angulation of impacted canine with the apex located in the inverted-Y region. As suggested by Rusu et al. [38], when the impacted upper canine was close to the
Fig. 4. Axial (A) and coronal (B) images illustrating the perforation in the lateral wall of the nasal cavity (long white arrow), the medial wall of the maxillary sinus (short white arrow) and the window at the anterior wall of the maxillary sinus made during the Caldwell–Luc operation (black arrow).
Please cite this article in press as: Kosalagood P, et al. Displacement of an impacted maxillary canine root fragment into the nasolacrimal duct: A diagnostic dilemma. J Oral Maxillofac Surg Med Pathol (2014), http://dx.doi.org/10.1016/j.ajoms.2014.10.001
G Model JOMSMP-333; No. of Pages 4
ARTICLE IN PRESS P. Kosalagood et al. / Journal of Oral and Maxillofacial Surgery, Medicine, and Pathology xxx (2014) xxx–xxx
4
maxillary sinus and nasal fossa, accurate radiological documentation for pre-operative planning has to be considered because of the risk of penetration during operation. In conclusion, reports of tooth structures being involved with the nasolacrimal drainage system are exceptionally rare. To our knowledge, the present report of a root fragment found in the nasolacrimal duct is the first case published. We suggest that CBCT is the most suitable radiographic technique to accurately define the anatomic relationship between a high-positioned, impacted maxillary canine and nearby vital anatomical structures. A small-FOV CBCT scan would suffice for this diagnostic indication and is therefore preferred over a large-volume CBCT or MSCT scan because of its limited radiation dose [39]. A precise diagnosis of impacted canine is essential for optimal treatment planning and the avoidance of complications. Acknowledgement The authors thank Dr. Onanong C Silkosessak and Mr. Ruben Pauwels for generous support in correcting the manuscript. References [1] Elefteriadis JN, Athanasiou AE. Evaluation of impacted canines by means of computerized tomography. Int J Adult Orthodon Orthognath Surg 1996;11:257–64. [2] Ericson S, Kurol J. Resorption of maxillary lateral incisors caused by ectopic eruption of the canines. Am J Orthod Dentofacial Orthop 1988;94: 503–13. [3] Ericson S, Kurol J. Incisor resorption caused by maxillary cuspids—a radiographic study. Angle Orthod 1987;57:332–46. [4] Fox NA, Fletcher GA, Horner K. Localizing maxillary canines using panoramic tomography. Br Dent J 1995;179:416–20. [5] Stewart JA, Heo G, Glover KE, Williamson PC, Lam EW, Major PW. Factors that relate to treatment duration for patients with palatally impacted maxillary canines. Am J Orthod Dentofacial Orthop 2001;119:216–25. [6] Mcsherry PF. The ectopic maxillary canine: a review. Br J Orthod 1998;25:209–16. [7] Khan A, Marwat HJ, Ali S, Malik F, Naureen S, Mahmood MA. Frequency of ectopic canines—a study. Pak Oral Dental J 2010;30(1):133–7. [8] Bishara SE. Impacted maxillary canines: a review. Am J Orthod Dentofacial Orthop 1992;101:159–71. [9] Peck S, Peck L, Kataja M. The palatally displaced canine as a dental anomaly of genetic origin. Angle Orthod 1994;64:249–56. [10] Thilander B, Jakobsson SO. Local factors in impaction of maxillary canines. Acta Odontol Scand 1968;26:145–68. [11] Rayne J. The unerupted maxillary canine. Dent Pract Dent Rec 1969;19:194–204. [12] Bass TB. Observations on the misplaced upper canine tooth. Dent Pract Dent Rec 1967;18:25–33. [13] Preda L, La Fianza A, Di Maggio EM, Dore R, Schifino MR, Campani R, et al. The use of spiral computed tomography in the localization of impacted maxillary canines. Dentomaxillofac Radiol 1997;26:236–41. [14] Walker L, Enciso R, Mah J. Three-dimensional localization of maxillary canines with cone-beam computed tomography. Am J Orthod Dentofacial Orthop 2005;128:418–23.
[15] Mason C, Papadakou P, Roberts GJ. The radiographic localization of impacted maxillary canines: a comparison of methods. Eur J Orthod 2001;23:25–34. [16] Kassel EE, Schatz CJ. Lacrimal apparatus. In: Som PM, Curtin HD, editors. Head and neck imaging. 4th ed. Mosby: St. Louis; 2003. [17] McCormick A, Sloan B. The diameter of the nasolacrimal canal measured by computed tomography: gender and racial differences. Clin Experiment Ophthalmol 2009;37:357–61. [18] Groessl SA, Sires BS, Lemke BN. An anatomical basis for primary acquired nasolacrimal duct obstruction. Arch Ophthalmol 1997;115:71–7. [19] Russell EJ, Czervionke L, Huckman M, Daniels D, McLachlan D. CT of the inferomedial orbit and the lacrimal drainage apparatus: Normal and pathologic anatomy. AJR Am J Roentgenol 1985;145:1147–54. [20] Tatlisumak E, Asian A, Comert A, Ozlugedik S, Acar HI, Tekdemir I. Surgical anatomy of the nasolacrimal duct on the lateral nasal wall as revealed by serial dissections. Anat Sci Int 2010;85:8–12. [21] Groell R, Schaffler GJ, Uggowitzer M, Szolar DH, Muellner K. CT-anatomy of the nasolacrimal sac and duct. Surg Radiol Anat 1997;19:189–91. [22] Alling CC, Helfrick JF, Alling RD. Impacted teeth. Philadelphia: WB Saunders; 1993. [23] Rohlin M, Rundquist L. Apical root anatomy of impacted maxillary canines. A clinical and radiographic study. Oral Surg Oral Med Oral Pathol 1984;58(2):141–7. [24] Cernochova P, Kanovska K, Krupa P. Morphology and position of the root apex in impacted maxillary canines. Scr Med (Brno) 2003;76:9–20. [25] El-Shall MA, Al-Qahtani MM, Al-Shehri YM, Al-Otibi SO. Surgical removal of impacted maxillary canines: the correlation between cone-beam CT findings and intraoperative findings. JPDA 2009;18:151–7. [26] Andreasen JO, Petersen JK, Laskin DM. Textbook and color atlas of tooth impactions. Munksgaard: Copenhagen; 1997. p. 160. [27] Smailiene D. Localization of impacted maxillary canines by palpation and orthopantomography. Medicina (Kaunas) 2002;38:825–9. [28] Bodner L, Tovi F, Zıv JB. Teeth in the maxillary sinus—imaging and management. J Laryngol Otol 1997;111:820–4. [29] Konen E, Faibel M, Kleinbaum Y, Wolf M, Lusky A, Hoffman C, et al. The value of the occipitomental (Waters’) view in diagnosis of sinusitis: A comparative study with computed tomography. Clin Radiol 2000;55:856–60. [30] Langland OE, Langlais RP, Preece JW. Principles of dental imaging. 2nd ed. Philadelphia: Lippincott Williams and Wilkins; 2002. [31] Bartley GB. Acquired lacrimal drainage obstruction: an etiologic classification system, case reports, and a review of the literature. Part 1. Ophthal Plast Reconstr Surg 1992;8:237–42. [32] Bartley GB. Acquired lacrimal drainage obstruction: an etiologic classification system, case reports, and a review of the literature. Part 2. Ophthal Plast Reconstr Surg 1992;8:243–9. [33] Bartley GB. Acquired lacrimal drainage obstruction: an etiologic classification system, case reports, and a review of the literature. Part 3. Ophthal Plast Reconstr Surg 1993;9:11–26. [34] Altas E, Karasen RM, Yilmaz AB, Aktan B, Kocer I, Erman Z. A case of a large dentigerous cyst containing a canine tooth in the maxillary antrum leading to epiphora. J Laryngol Otol 1997;111:641–3. [35] Bajaj MS, Mahindrakar A, Pushker N. Dentigerous cyst in the maxillary sinus: a rare cause of nasolacrimal obstruction. Orbit 2003;22:289–92. [36] Ray B, Bandyopadhyay SN, Das D, Adhikary B. A rare cause of nasolacrimal duct obstruction: dentigerous cyst in the maxillary sinus. Indian J Ophthalmol 2009;57:465–7. [37] Alexandrakis G, Hubbell RN, Aitken PA. Nasolacrimal duct obstruction secondary to ectopic teeth. Ophthalmology 2000;107:189–92. [38] Rusu MC, Comes CA, Stanciu D, Ciuluvic˘a RC, Motoc A, Niculescu MC, et al. Altered anatomy in a case with a buccally impacted maxillary canine tooth. Rom J Morphol Embryol 2010;51:783–6. [39] Pauwels R, Beinsberger J, Collaert B, Theodorakou C, Rogers J, Walker A, et al. Effective dose range for dental cone beam computed tomography scanners. Eur J Radiol 2012;81:267–71.
Please cite this article in press as: Kosalagood P, et al. Displacement of an impacted maxillary canine root fragment into the nasolacrimal duct: A diagnostic dilemma. J Oral Maxillofac Surg Med Pathol (2014), http://dx.doi.org/10.1016/j.ajoms.2014.10.001
ARTICLE IN PRESS Journal of Oral and Maxillofacial Surgery, Medicine, and Pathology xxx (2014) xxx–xxx
Contents lists available at ScienceDirect
Journal of Oral and Maxillofacial Surgery, Medicine, and Pathology journal homepage: www.elsevier.com/locate/jomsmp
Case Report
Displacement of an impacted maxillary canine root fragment into the nasolacrimal duct: A diagnostic dilemma Pasupen Kosalagood a , Pornkawee Charoenlarp a,∗ , Soontra Panmekiate a , Somchai Sessirisombat b a
Department of Radiology, Faculty of Dentistry, Chulalongkorn University, Henry Dunant Road, Pathumwan District, Bangkok 10330, Thailand Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Chulalongkorn University, Henry Dunant Road, Pathumwan District, Bangkok 10330, Thailand b
a r t i c l e
i n f o
Article history: Received 3 September 2013 Received in revised form 19 September 2014 Accepted 6 October 2014 Available online xxx Keywords: Impacted canine Nasolacrimal duct Surgical complication Localization Cone beam CT
a b s t r a c t Maxillary canines are the second most common impacted teeth after third molars. The surgical removal of impacted canines should be carefully considered in order to avoid intra- and post-operative complications. To reduce the chance of unwanted consequences, a thorough and careful diagnostic process including sufficient radiographic examination must be performed. Conventional radiographic techniques are commonly used for localization. However, advanced 3D imaging should be done in cases where 2D radiographs cannot provide sufficient information regarding the position of an impacted canine and its relationship with surrounding structures to minimize surgical complications. Here, we reported a rare case, in which an impacted canine root fragment was displaced into the adjacent nasolacrimal duct. This situation leads to partial duct obstruction. Through discussion of this case, we drew attention to a few subtle features of 2D radiographs showing the need and rationale for advanced imaging modalities such as CBCT as supplementary options. © 2014 Asian AOMS, ASOMP, JSOP, JSOMS, JSOM, and JAMI. Published by Elsevier Ltd. All rights reserved.夽
1. Introduction Impacted teeth are teeth which do not have enough space for eruption into the oral cavity. Commonly, their eruption paths are blocked by other structures. Impacted teeth can cause detrimental effects including damage to nearby teeth and are sometimes associated with cysts or tumors. The prevalence of impacted maxillary canines is reported to be 0.9–3% [1–5], which is second only to mandibular third molars [6,7]. Impacted maxillary canines occur twice as often in females than in males and have a high familial association. The incidence of impacted maxillary canines in Caucasians is fivefold that of Asians [8,9]. Eighty-five percent of impacted permanent maxillary canine crowns are palatal in position, while the remaining are in labial aspect [10–12]. Management of impacted maxillary canines includes orthodontic treatment with or without surgical treatment, which requires accurate diagnosis
夽 Asian AOMS: Asian Association of Oral and Maxillofacial Surgeons; ASOMP: Asian Society of Oral and Maxillofacial Pathology; JSOP: Japanese Society of Oral Pathology; JSOMS: Japanese Society of Oral and Maxillofacial Surgeons; JSOM: Japanese Society of Oral Medicine; JAMI: Japanese Academy of Maxillofacial Implants. ∗ Corresponding author. Tel.: +66 2 218 8714/5; fax: +66 2 218 8715. E-mail address: kiwi [email protected] (P. Charoenlarp).
and precise determination of the location, inclination, and longitudinal axis of the impacted canine in relation to surrounding structures [13,14]. Several conventional radiographic techniques are used during treatment planning of impacted teeth, including periapical, topographic or cross-sectional occlusal, panoramic, and cephalometric radiographs or a combination of these views using parallax or right angle techniques [15]. However, it is often difficult to distinguish minute details and to accurately define anatomical relationships [1]. Therefore, limited field of view (FOV) 3D imaging could be considered as an alternative for particular cases that demand detailed information regarding neighboring structures (i.e. relative inclination of the impacted tooth, adjacent root resorption or thickness of overlying bone) in order to reduce possible surgical or non-surgical complications and to increase value in treatment planning for a more predictable outcome. Several potential consequences may arise during the removal process of impacted maxillary canines such as injury to adjacent teeth, fractured roots, and perforation into nasal cavity or maxillary sinus with or without displacement of the root fragment. The latter one may subsequently lead to secondary acquired lacrimal drainage obstruction. The nasolacrimal duct is a structure which carries tears from the lacrimal sac into the nasal cavity through its superior intraosseous and inferior membranous portions. The anatomy of
http://dx.doi.org/10.1016/j.ajoms.2014.10.001 2212-5558/© 2014 Asian AOMS, ASOMP, JSOP, JSOMS, JSOM, and JAMI. Published by Elsevier Ltd. All rights reserved.夽
Please cite this article in press as: Kosalagood P, et al. Displacement of an impacted maxillary canine root fragment into the nasolacrimal duct: A diagnostic dilemma. J Oral Maxillofac Surg Med Pathol (2014), http://dx.doi.org/10.1016/j.ajoms.2014.10.001
G Model JOMSMP-333; No. of Pages 4
ARTICLE IN PRESS P. Kosalagood et al. / Journal of Oral and Maxillofacial Surgery, Medicine, and Pathology xxx (2014) xxx–xxx
2
the root, but the root fragment could not be found within the sinus. Consequently, a cone-beam computed tomography (CBCT) examination was ordered to re-evaluate the exact location of the root fragment. On the CBCT scan, the 4.88 mm in its largest diameter root fragment was shown in the superior portion of the right nasolacrimal duct near the orbital floor (Fig. 3). The bone perforations at the lateral wall of the right nasal cavity and the medial wall of the right maxillary sinus were 5.00 and 2.42 mm in size, respectively (Fig. 4). Because of these findings, the patient was referred to an ophthalmologist for proper management of possible secondary acquired lacrimal drainage obstruction. 3. Discussion
Fig. 1. The anatomy of the nasolacrimal duct.
the nasolacrimal duct is shown in Fig. 1. The intraosseous portion of the duct starts from the medial aspect of the eyes and travels posterolaterally along the lateral nasal wall, while the 5-mm long membranous or meatal part runs beneath the nasal mucosa [16–19]. Eventually, the canal opens into the inferior meatus under the inferior nasal turbinate through a pin-point, triangular or slitlike opening known as the valve of Hasner [20]. The reported mean length of the intraosseous part is 11.2 ± 2.6 mm (range: 6–21 mm), and its average diameter is 3.7 ± 0.7 mm (range: 2–7 mm) [21]. The size of the canal varies with patient’s age, sex and race [16]. Its diameter is larger in males than females and increases in size with age [17,18]. There is also a geographic variability, as Pacific people are shown to have wider canals than Caucasian or New Zealand Maori [17]. The possibility of any foreign body entering the nasolacrimal duct is minimal. In this report, a rare case of surgical complication in which the canine root fragment was displaced into the nasolacrimal duct, potentially leading to partial obstruction of the duct, is reviewed. Through discussion of the case, we drew attention to a few subtle features of 2D radiographs showing the need for advanced imaging modalities such as CBCT as a supplementary option to avoid such problems. 2. Case report A 21-year-old female was referred from an orthodontist to the Oral and Maxillofacial Surgery Clinic at the Faculty of Dentistry, Chulalongkorn University for surgical removal of an impacted right permanent maxillary canine. An original panoramic radiograph was available at the time, but was missing during preparation of the current publication. It was reported to have an impacted canine with the crown located between the roots of lateral incisor and first premolar, and the root positioned high in the inverted Y region. The patient underwent surgical removal of this tooth under local anesthesia. A full mucoperiosteal flap was reflected, and the labial cortex covering the crown of the impacted canine was removed before elevating the canine. During this procedure, the apical one-third of the root fractured and was retained in the site. An attempt to remove the root fragment failed, and the root fragment disappeared. A postoperative panoramic radiograph (Fig. 2) was taken three days later, and the root fragment was detected at the supero-medial region of the right maxillary sinus at the level of the middle/inferior concha. A Waters’ radiograph was then prescribed, but the location of the root fragment cannot be clearly identified. After the surgeon’s initial interpretation, a Caldwell–Luc operation was attempted to retrieve
The development of the maxillary canine begins within a complicated area of facial bones, surrounded by the orbit, the nasal cavity and maxillary sinus [22]. If impaction occurs, the canine’s root can be found deep in the maxilla among those structures. In addition, the prevalence of dilacerated roots is common – reported to be 26–57% [23,24], while few studies described post-operative nasal wall perforation as a complication due to root apex proximity or intra-operative surgical procedure [25,26]. Hence, surgical removal of impacted maxillary canine should be carefully considered to avoid intra- and post-operative complications. In order to achieve this goal, precise tooth localization is crucial. In more than 60% of cases, it is possible to decide whether the crown of the impacted tooth is facial or palatal using palpation [27]. In other cases, radiographic assessment is needed for effective localization [15]. A conventional two-dimensional (2D) radiograph is commonly acquired to investigate location of the impaction. Panoramic radiography is usually prescribed to determine angulation, mesio-distal position, depth of impaction, and the relationship with adjacent structures. However, diagnosis and treatment planning based on 2D imaging is difficult and prone to misinterpretation due to structural superimposition, image magnification and image distortion. Three-dimensional modalities not only offer precise location of impacted maxillary canines, but also show root configuration and dimension, associated pathologies, root proximity and availability of surrounding bone, allowing for proper treatment planning [28,29]. Moreover, if any complication occurs, detailed information of structures in complex anatomical areas can be properly visualized, including bone perforations, location and size of fractured parts and their distance to surrounding landmarks. In our case, the root fragment, dislocated into the nasolacrimal duct, was not immediately recognized from conventional radiographs. Despite the fact that the post-operative panoramic radiograph (Fig. 2) revealed the root of interest within the sinus outline at the mid-sinus level closing to the antero-medial antral wall, it was in an unusual location within the sinus considering the force
Fig. 2. Panoramic radiograph showing the root fragment (arrow) by the medial wall of the right maxillary sinus.
Please cite this article in press as: Kosalagood P, et al. Displacement of an impacted maxillary canine root fragment into the nasolacrimal duct: A diagnostic dilemma. J Oral Maxillofac Surg Med Pathol (2014), http://dx.doi.org/10.1016/j.ajoms.2014.10.001
G Model JOMSMP-333; No. of Pages 4
ARTICLE IN PRESS P. Kosalagood et al. / Journal of Oral and Maxillofacial Surgery, Medicine, and Pathology xxx (2014) xxx–xxx
3
Fig. 3. Multiplanar reconstructed images comprising axial (A), coronal (B) and sagittal (C) views. The white arrows in the images point to the root fragment in the nasolacrimal canal.
of gravity and the anatomy of the maxillary sinus. Inside an empty cavity, any foreign object should always fall downward in accordance with the head’s position unless the following exceptions are present. First, it might be trapped by partial septation. Second, any inflammation process might roughen and thicken sinus mucosa resulting in suspension of the root piece. In addition, the principle of panoramic image acquisition, in which the middle portion of the nasal cavity superimposes on the maxillary sinus, should be kept in mind [30]. Therefore, the object of interest in our case could situate inside either the nasal or the antral cavities. An additional right angle image, a Waters’ view in this case, was also prescribed but no extra information was provided. With the above-mentioned 2D radiographic finding, advanced 3D imaging should be considered as the modality of choice to obtain more details in order to avoid unexpected complications for cases similar to the one reported here. It should be emphasized that 2D radiographic views are not always able to illustrate the exact location of the root fragment, particularly in the naso-antral complex. The chance that a root fragment is pushed into the nasolacrimal duct is very rare owing to several factors: (1) position, angulation and relationship between impacted root and nasolacrimal duct, (2) distance between root fragment and the opening of nasolacrimal duct, (3) diameters of root fragment compared to Hasner’s valve, (4) types of membranous valve openings and (5) intra- and postoperative force and direction of action. From the literature review, there is no report concerning the first three factors. Regarding the membranous opening, a high incidence of pin-point (33%) and
slit-like (40%) openings with very small diameters compared to triangular types has been reported [21]. In the presented case, the root fragment went through this constricted barrier and was displayed in the superior part of nasolacrimal duct. The size of this root fragment (maximum diameter: 4.88 mm) was slightly less than the perforated lateral nasal wall (5.00 mm). Combined with the fact that the shortest migratory path distance from the perforation of the lateral nasal wall to the opening of the intraosseous part of the nasolacrimal duct was 10.83 mm, it can be speculated that the root fragment was pushed through the lateral wall of the nasal cavity and eventually into the membranous and intraosseous part of the nasolacrimal duct. Secondary acquired lacrimal drainage obstruction may result from a variety of infectious, neoplastic, inflammatory, traumatic, or mechanical causes as well as from unusual dental origins [31–33]. Few cases of dentigerous cysts have been reported to cause obstruction to the lacrimal drainage system [34–36], while two cases of ectopic teeth compressing the nasolacrimal ducts have also been described [37]. The symptoms of nasolacrimal ducts obstruction commonly presents with epiphora and acute or chronic dacryocystitis [37], and required complex treatment as endoscopic dacryocystorhinostomy (DCR). Despite its low incidence, this kind of complication is not worth the risk. The authors propose that CBCT examination should be considered pre-operatively in case the initial evaluation indicates vertical angulation of impacted canine with the apex located in the inverted-Y region. As suggested by Rusu et al. [38], when the impacted upper canine was close to the
Fig. 4. Axial (A) and coronal (B) images illustrating the perforation in the lateral wall of the nasal cavity (long white arrow), the medial wall of the maxillary sinus (short white arrow) and the window at the anterior wall of the maxillary sinus made during the Caldwell–Luc operation (black arrow).
Please cite this article in press as: Kosalagood P, et al. Displacement of an impacted maxillary canine root fragment into the nasolacrimal duct: A diagnostic dilemma. J Oral Maxillofac Surg Med Pathol (2014), http://dx.doi.org/10.1016/j.ajoms.2014.10.001
G Model JOMSMP-333; No. of Pages 4
ARTICLE IN PRESS P. Kosalagood et al. / Journal of Oral and Maxillofacial Surgery, Medicine, and Pathology xxx (2014) xxx–xxx
4
maxillary sinus and nasal fossa, accurate radiological documentation for pre-operative planning has to be considered because of the risk of penetration during operation. In conclusion, reports of tooth structures being involved with the nasolacrimal drainage system are exceptionally rare. To our knowledge, the present report of a root fragment found in the nasolacrimal duct is the first case published. We suggest that CBCT is the most suitable radiographic technique to accurately define the anatomic relationship between a high-positioned, impacted maxillary canine and nearby vital anatomical structures. A small-FOV CBCT scan would suffice for this diagnostic indication and is therefore preferred over a large-volume CBCT or MSCT scan because of its limited radiation dose [39]. A precise diagnosis of impacted canine is essential for optimal treatment planning and the avoidance of complications. Acknowledgement The authors thank Dr. Onanong C Silkosessak and Mr. Ruben Pauwels for generous support in correcting the manuscript. References [1] Elefteriadis JN, Athanasiou AE. Evaluation of impacted canines by means of computerized tomography. Int J Adult Orthodon Orthognath Surg 1996;11:257–64. [2] Ericson S, Kurol J. Resorption of maxillary lateral incisors caused by ectopic eruption of the canines. Am J Orthod Dentofacial Orthop 1988;94: 503–13. [3] Ericson S, Kurol J. Incisor resorption caused by maxillary cuspids—a radiographic study. Angle Orthod 1987;57:332–46. [4] Fox NA, Fletcher GA, Horner K. Localizing maxillary canines using panoramic tomography. Br Dent J 1995;179:416–20. [5] Stewart JA, Heo G, Glover KE, Williamson PC, Lam EW, Major PW. Factors that relate to treatment duration for patients with palatally impacted maxillary canines. Am J Orthod Dentofacial Orthop 2001;119:216–25. [6] Mcsherry PF. The ectopic maxillary canine: a review. Br J Orthod 1998;25:209–16. [7] Khan A, Marwat HJ, Ali S, Malik F, Naureen S, Mahmood MA. Frequency of ectopic canines—a study. Pak Oral Dental J 2010;30(1):133–7. [8] Bishara SE. Impacted maxillary canines: a review. Am J Orthod Dentofacial Orthop 1992;101:159–71. [9] Peck S, Peck L, Kataja M. The palatally displaced canine as a dental anomaly of genetic origin. Angle Orthod 1994;64:249–56. [10] Thilander B, Jakobsson SO. Local factors in impaction of maxillary canines. Acta Odontol Scand 1968;26:145–68. [11] Rayne J. The unerupted maxillary canine. Dent Pract Dent Rec 1969;19:194–204. [12] Bass TB. Observations on the misplaced upper canine tooth. Dent Pract Dent Rec 1967;18:25–33. [13] Preda L, La Fianza A, Di Maggio EM, Dore R, Schifino MR, Campani R, et al. The use of spiral computed tomography in the localization of impacted maxillary canines. Dentomaxillofac Radiol 1997;26:236–41. [14] Walker L, Enciso R, Mah J. Three-dimensional localization of maxillary canines with cone-beam computed tomography. Am J Orthod Dentofacial Orthop 2005;128:418–23.
[15] Mason C, Papadakou P, Roberts GJ. The radiographic localization of impacted maxillary canines: a comparison of methods. Eur J Orthod 2001;23:25–34. [16] Kassel EE, Schatz CJ. Lacrimal apparatus. In: Som PM, Curtin HD, editors. Head and neck imaging. 4th ed. Mosby: St. Louis; 2003. [17] McCormick A, Sloan B. The diameter of the nasolacrimal canal measured by computed tomography: gender and racial differences. Clin Experiment Ophthalmol 2009;37:357–61. [18] Groessl SA, Sires BS, Lemke BN. An anatomical basis for primary acquired nasolacrimal duct obstruction. Arch Ophthalmol 1997;115:71–7. [19] Russell EJ, Czervionke L, Huckman M, Daniels D, McLachlan D. CT of the inferomedial orbit and the lacrimal drainage apparatus: Normal and pathologic anatomy. AJR Am J Roentgenol 1985;145:1147–54. [20] Tatlisumak E, Asian A, Comert A, Ozlugedik S, Acar HI, Tekdemir I. Surgical anatomy of the nasolacrimal duct on the lateral nasal wall as revealed by serial dissections. Anat Sci Int 2010;85:8–12. [21] Groell R, Schaffler GJ, Uggowitzer M, Szolar DH, Muellner K. CT-anatomy of the nasolacrimal sac and duct. Surg Radiol Anat 1997;19:189–91. [22] Alling CC, Helfrick JF, Alling RD. Impacted teeth. Philadelphia: WB Saunders; 1993. [23] Rohlin M, Rundquist L. Apical root anatomy of impacted maxillary canines. A clinical and radiographic study. Oral Surg Oral Med Oral Pathol 1984;58(2):141–7. [24] Cernochova P, Kanovska K, Krupa P. Morphology and position of the root apex in impacted maxillary canines. Scr Med (Brno) 2003;76:9–20. [25] El-Shall MA, Al-Qahtani MM, Al-Shehri YM, Al-Otibi SO. Surgical removal of impacted maxillary canines: the correlation between cone-beam CT findings and intraoperative findings. JPDA 2009;18:151–7. [26] Andreasen JO, Petersen JK, Laskin DM. Textbook and color atlas of tooth impactions. Munksgaard: Copenhagen; 1997. p. 160. [27] Smailiene D. Localization of impacted maxillary canines by palpation and orthopantomography. Medicina (Kaunas) 2002;38:825–9. [28] Bodner L, Tovi F, Zıv JB. Teeth in the maxillary sinus—imaging and management. J Laryngol Otol 1997;111:820–4. [29] Konen E, Faibel M, Kleinbaum Y, Wolf M, Lusky A, Hoffman C, et al. The value of the occipitomental (Waters’) view in diagnosis of sinusitis: A comparative study with computed tomography. Clin Radiol 2000;55:856–60. [30] Langland OE, Langlais RP, Preece JW. Principles of dental imaging. 2nd ed. Philadelphia: Lippincott Williams and Wilkins; 2002. [31] Bartley GB. Acquired lacrimal drainage obstruction: an etiologic classification system, case reports, and a review of the literature. Part 1. Ophthal Plast Reconstr Surg 1992;8:237–42. [32] Bartley GB. Acquired lacrimal drainage obstruction: an etiologic classification system, case reports, and a review of the literature. Part 2. Ophthal Plast Reconstr Surg 1992;8:243–9. [33] Bartley GB. Acquired lacrimal drainage obstruction: an etiologic classification system, case reports, and a review of the literature. Part 3. Ophthal Plast Reconstr Surg 1993;9:11–26. [34] Altas E, Karasen RM, Yilmaz AB, Aktan B, Kocer I, Erman Z. A case of a large dentigerous cyst containing a canine tooth in the maxillary antrum leading to epiphora. J Laryngol Otol 1997;111:641–3. [35] Bajaj MS, Mahindrakar A, Pushker N. Dentigerous cyst in the maxillary sinus: a rare cause of nasolacrimal obstruction. Orbit 2003;22:289–92. [36] Ray B, Bandyopadhyay SN, Das D, Adhikary B. A rare cause of nasolacrimal duct obstruction: dentigerous cyst in the maxillary sinus. Indian J Ophthalmol 2009;57:465–7. [37] Alexandrakis G, Hubbell RN, Aitken PA. Nasolacrimal duct obstruction secondary to ectopic teeth. Ophthalmology 2000;107:189–92. [38] Rusu MC, Comes CA, Stanciu D, Ciuluvic˘a RC, Motoc A, Niculescu MC, et al. Altered anatomy in a case with a buccally impacted maxillary canine tooth. Rom J Morphol Embryol 2010;51:783–6. [39] Pauwels R, Beinsberger J, Collaert B, Theodorakou C, Rogers J, Walker A, et al. Effective dose range for dental cone beam computed tomography scanners. Eur J Radiol 2012;81:267–71.
Please cite this article in press as: Kosalagood P, et al. Displacement of an impacted maxillary canine root fragment into the nasolacrimal duct: A diagnostic dilemma. J Oral Maxillofac Surg Med Pathol (2014), http://dx.doi.org/10.1016/j.ajoms.2014.10.001