METHODS: CT scans of 50 lower limbs were analyzed. Key anatomical landmarks such as the medial epicondyle (ME), lateral epicondyle, and transepicondylar width (TEW) were determined on 3D models constructed from the CT images. Best-fit planes placed on the most distal and posterior loci of points on the femoral condyles were used to define the distal and posterior joint lines, respectively. Statistical analysis was performed to determine the relationships between the anatomical landmarks and the distal and posterior joint lines.
RESULTS: There was a strong correlation between the distance from the ME to the distal joint line of the medial condyle (MEDC) and the distance from the ME to the posterior joint line of the medial condyle (MEPC) (p
METHODS: Thirty patients who underwent distal volar locking plate for distal radius fracture were included in a retrospective study. In all 30 patients no dorsal and intra-articular screw penetration were detected on standard AP and lateral views of a plain radiograph. CT scan of the operated wrist was performed to determine the number of intra-articular and dorsal screw penetrations. Clinical examination was performed to determine the wrist functions in comparison to the normal wrist.
RESULTS: Nineteen wrists were noted to have screw penetration either dorsally or intraarticularly. The highest incidence is in the 2nd extensor compartment where 13 screws had penetrated with a mean of 2.46 mm. Six screws penetrated into the distal radial ulnar joint and five screws into the wrist joint with a mean of 2.83 mm and 2.6 mm, respectively. However, there was no incidence of tendon irritation or rupture.
CONCLUSIONS: This study demonstrated a high incidence of dorsal and intra-articular screw penetration detected by CT scan which was not apparent in plain radiograph. We recommend that surgeons adhere to the principle of only near cortex fixation and downsizing the locking screw length by 2 mm.
MATERIALS AND METHODS: In this study, 20 implant sites in patients were selected. Ridge mapping was done through a vacuum press template at three buccal (B1, B2, B3), three lingual (L1, L2, L3), and one crestal (C) points for each implant site. Readings were transferred onto the cast, and surgical guides were fabricated for implant placement. Postoperative cone beam computerized tomography (CBCT) was done to assess planned and achieved implant position. Comparison was done between soft tissue depths and implant distance from the crest of alveolar bone determined by the ridge mapping technique with measurements done on CBCT. The points used for ridge mapping were used as the reference for measurements. The data were analyzed using paired t test. p < 0.05 was considered to be statistically significant.
RESULTS: On comparing the mean values of soft tissue depths from the ridge mapping and CBCT data, insignificant differences were found at B1, B2, L1, L2, L3, and C, but significant differences were found at B3. On comparing the implant distances from alveolar bone from both the data, insignificant differences were found at B, B2, B3, L1, L2, and L3 and significant difference was found at the crest in the mean values.
CONCLUSION: Under the limitations of the above study, it can be concluded that a simple chairside procedure like ridge mapping can be used as an effective way for guided implant placement in sufficient available alveolar bone.
Method: Maxillary CBCT images of two-hundred-and-fifty-seven consecutive patients (163 men, 94 women, mean age 42 years) were analyzed. Samples were later divided into dentate (n = 142) and posteriorly edentulous (n = 115) jaws. Using both alveolar ridge and tooth location as reference points, the distance and diameter of IA were assessed.
Result: The IA was seen in 63.7% of all sinuses with 68.2% in dentate and 62.4% in edentulous. Mean distance and diameter of IA across the posterior tooth locations were 17.9 ± 3.0 mm and 1.4 ± 0.5 mm (dentate) and 15.1 ± 3.0 mm and 1.0 ± 0.5 mm (posteriorly edentulous), respectively. In each sample, there were no significant differences in distance-alveolar ridge and no significant correlations in diameter-tooth location. A statistically significant Pearson coefficient correlation between diameter and distance in dentate state was observed (r = -0.6).
Conclusion: This study reveals that dentate maxillary jaws present larger diameters as compared to posteriorly edentulous jaws, although the IA course remains the same. As these canal structures contain neurovascular bundles with diameters that may be large enough to cause clinically substantial complications, a thorough pre-surgical planning is therefore highly advisable.