Implant therapy in a surgical specialty clinic: an analysis of patients, indications, surgical procedures, risk factors, and early failures

PURPOSE The aim of this study was to analyze the patient pool referred to a specialty clinic for implant surgery over a 3-year period. MATERIALS AND METHODS All patients receiving dental implants between 2008 and 2010 at the Department of Oral Surgery and Stomatology were included in the study. As primary outcome parameters, the patients were analyzed according to the following criteria: age, sex, systemic diseases, and indication for therapy. For the inserted implants, the type of surgical procedure, the types of implants placed, postsurgical complications, and early failures were recorded. A logistic regression analysis was performed to identify possible local and systemic risk factors for complications. As a secondary outcome, data regarding demographics and surgical procedures were compared with the findings of a historic study group (2002 to 2004). RESULTS A total of 1,568 patients (792 women and 776 men; mean age, 52.6 years) received 2,279 implants. The most frequent indication was a single-tooth gap (52.8%). Augmentative procedures were performed in 60% of the cases. Tissue-level implants (72.1%) were more frequently used than bone-level implants (27.9%). Regarding dimensions of the implants, a diameter of 4.1 mm (59.7%) and a length of 10 mm (55.0%) were most often utilized. An early failure rate of 0.6% was recorded (13 implants). Patients were older and received more implants in the maxilla, and the complexity of surgical interventions had increased when compared to the patient pool of 2002 to 2004. CONCLUSION Implant therapy performed in a surgical specialty clinic utilizing strict patient selection and evidence-based surgical protocols showed a very low early failure rate of 0.6%.

Anterior superior alveolar nerve (ASAN): A morphometric-anatomical Analysis

The anterior superior alveolar nerve (ASAN) is a branch of the infraorbital nerve. Only few studies have morphometrically evaluated the course of the ASAN. Midfacial segments of ten hemisectioned fresh adult cadaver heads were dissected to uncover the anterior wall of the maxilla. Specimens were subsequently decalcified and the bone overlying the ASAN was removed under a microscope to expose the ASAN. Its branching pattern from the infraorbital nerve was recorded, and the course of the ASAN within the anterior wall of the maxillary sinus was morphometrically assessed measuring distances to predefined landmarks using a digital caliper. A distinct ASAN was observed in all specimens. It arose lateral (six cases) or inferior (four cases) from the infraorbital nerve. The point of origin was located at a mean distance of 12.2 ± 5.79 mm posterior to the infraorbital foramen. The ASAN was located on average 2.8 ± 5.13 mm lateral to the infraorbital foramen. After coursing medially, the ASAN ran inferior to the foramen at a mean distance of 5.5 ± 3.07 mm. When approaching the nasal aperture, the loop of the ASAN was on average 13.6 ± 3.07 mm above the nasal floor. The horizontal mean distance from the ASAN to the nasal aperture was 4.3 ± 2.74 mm halfway down from the loop, and 3.3 ± 2.60 mm at the floor of the nose, respectively. In conclusion, the present study evaluated the course of the ASAN relative to the infraorbital foramen and nasal aperture. This information is helpful to avoid damage to this anatomical structure during interventions in the infraobrital region of the maxilla. Further, knowledge of the course of the ASAN and of its bony correlate (canalis sinuosus) may be valuable in interpreting anesthetic or radiologic findings in the anterior maxilla.

Indications and Frequency for the Use of Cone Beam Computed Tomography for Implant Treatment Planning in a Specialty Clinic

PURPOSE To analyze the indications and frequency for three-dimensional (3D) imaging for implant treatment planning in a pool of patients referred to a specialty clinic over a 3-year period. MATERIALS AND METHODS All patients who received dental implants between 2008 and 2010 at the Department of Oral Surgery and Stomatology at the University of Bern were included in the study. The influence of age, gender, and time of treatment (2008 to 2010) on the frequency of use of two-dimensional (2D) radiographic imaging modalities alone or in combination with 3D cone beam computed tomography (CBCT) scans was analyzed. Furthermore, the influence of the indication, location, and need for bone augmentation on the frequency of use of 2D imaging modalities alone or in combination with CBCT was evaluated. RESULTS In all, 1,568 patients (792 women and 776 men) received 2,279 implants. Overall, 633 patients (40.4%) were analyzed with 2D imaging procedures alone. CBCT was performed in 935 patients (59.6%). There was a statistically significant increase in CBCT between 2008 and 2010. Patients older than 55 years received a CBCT scan in addition to 2D radiographic imaging statistically significantly more often. Additional 3D imaging was most frequently performed in the posterior maxilla, whereas 2D radiographs alone exhibited the highest frequency in the anterior mandible. The combination of 2D with CBCT was used predominantly for implant placement with simultaneous or staged guided bone regeneration or sinus elevation. CONCLUSION Based on these findings from a specialty clinic, the use of additional CBCT imaging for implant treatment planning is influenced by the indication, location, local anatomy (including the need for bone augmentation), and the age of the patient.