Management of a dental implant displaced into the mandibular bone marrow space: Case reports

Abstract

When an implant fixture is displaced to the bone marrow defect site of the mandible, damage to the inferior alveolar nerve may occur. To minimize postoperative side effects, an accurate radiological evaluation should be made and the best method of removal should be considered. Here, we report two cases of implant removal in patients referred to our hospital who had an implant fixture displaced by a mandibular bone marrow defect, and we also propose a standardized method for removal of the implant. Two patients were referred to our clinic with displacement of an implant fixture to the mandibular bone marrow space. For removal of the implant, a trapezoidal bone window was designed with the buccal cortical bone of the drilling hole as the superior margin. An osteotomy was performed on the cortical bone. The implant was gently moved upwards and removed. Healing was uneventful with no neurological complications.

Removal of a Horizontally Displaced Dental Implant below the Mandibular Canal

“…Kim et al [2] reported that they found an almost-missing trabecular bone in the area of implantation in five cases. The low bone quality and low mineral density are the main causes of implant displacement during surgery [3,4,6,18,31]. In the present case, the average mineral bone density (265:32 ± 86:41 HU) was twice lower than the average reported values in this area-455-642 HU [1]; 556 ± 80 HU [26]; and 628:0 ± 20:19 HU [30].…”

“…Displacement of a dental implant into the body of the mandible is a severe but rare complication [18] compared with other well-known complications during the surgical stage such as: hemorrhage, damage to the lower alveolar nerve, damage to the adjacent tooth, lack of primary stability, and implant dislocation in adjacent soft tissue spaces [5,[19][20][21].…”

“…Low bone density of trabecular bone is observed only in 15-20% of the cases [27,30]. Accidental implant displacement in the posterior mandible is mostly associated with overpreparation of the implant site, subcrestal implant positioning, poor BIC, and insufficient or a lack of primary stability [2,18,23,24]. The low bone quality and density contribute to implant displacement during surgery [6].…”