case_images: PMC5426152_01
case_images: Preoperative images: (a) Intraoral, (b) Type II dens invaginatus in 34, (c) occlusal radiograph showing (d) panoramic radiograph, (e) axial view in cone-beam computed tomography image, (f) three-dimensional reconstruction of mandible, and (g) coronal cone-beam computed tomography section
case_images: CCD-8-158-g001.jpg
case_images: PMC5426152_01_CCD-8-158-g001.jpg
case_images: F1
case_images: The mandibular first premolar had a slightly greater mesiodistal width, normal color, normal gingival tissues, and probing depth [Figure 1a]. Radiographic examination [Figure 1c and d] showed an extensive multilocular radiolucency causing severe hollowing out and weakening of the body of the mandible. A Type II dens invaginatus was observed in 34 [Figure 1b]. Cone beam computed tomography (CBCT) examination [Figure 1e-g] revealed a complex invagination in coronal third of first premolar on mesiolingual aspect close to the external root surface.
case_images: (a) Working length, (b) mineral trioxide aggregate apical plug, (c) fiber postcoated with foil, (d) fiber reinforced composite build up, (e and f) postobturation intraoral periapical, (g and h) 6 months recall, (i) metal ceramic crowns placement, (j) 3 years recall radiograph
case_images: CCD-8-158-g003.jpg
case_images: PMC5426152_01_CCD-8-158-g003.jpg
case_images: F3
case_images: Cleaning and shaping of 35 and 36 was done with crown down technique 5.25% sodium hypochlorite (NaOCl) as irrigant and obturated with cold lateral condensation [Figure 3f]. Elimination of the dead pulp space in the invaginated mandibular premolar [Figure 3a] resulted in significant weakening of the remaining root. Mineral trioxide aggregate was placed in the apical third using sonic activation (EndoActivator, Dentsply Maillefer, Switzerland) and temporized [Figure 3b]. Radix fiber post no. 5 (Radix Fiber Post, Dentsply Maillefer), covered with aluminum foil and held passively in the center of the canal with locking tweezers [Figure 3c]. The bonding agent and resin cement were light cured for 60 s through the post [Figure 3d and e]. Six-month follow-up showed significant healing of the periapical lesion [Figure 3g and h]. The endodontically treated teeth were asymptomatic and restored with metal ceramic crowns [Figure 3i]. Recall at 3 years shows excellent healing of the periapical lesion and asymptomatic involved teeth with no evidence of any root fracture [Figure 3j].