Mechanical Evaluation of 70:30 Poly (L/DL-Lactide) Bone Screws After

Use of cannulated bone screws, as compared with use of traditional bone screws, has been reported to decrease surgical time, allow for more precise screw placement, and reduce sources of error. Cannulation of the smaller-size screws that are routinely used in foot surgery has not been available until the last few years. This article reports on the use of the small cannulated screws manufactured by Alphatec Manufacturing, Inc (Palm Desert, California). The screw sizes available in the Mini Lag Screw System are 2.7, 3.5, and 4.0 mm. A long-term clinical and radiographic prospective evaluation of 70 procedures performed on 49 patients was conducted. The follow-up time for all patients was 2 years. None of the 70 implants fractured, and seven procedures (in seven patients) resulted in some type of implant-fixation failure. All of the fixation failures, however, appeared to be related to an untoward event or patient noncompliance. These smaller cannulated screws proved to be a reliable and effective means of fixation in foot surgery.

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‘N-Angle’: Clinical Indicator for Predictable Insertion of Ramal Bone Screws

The Journal of Indian Orthodontic Society ◽

10.1177/0301574221991947 ◽

2021 ◽

pp. 030157422199194

Author(s):

Vivek J Patni ◽

Neeraj E Kolge ◽

Madhura J Pednekar

Keyword(s):

Soft Tissue ◽

Average Distance ◽

Primary Objective ◽

Bone Screws ◽

Neurovascular Bundle ◽

Primary Concern ◽

Bone Screw ◽

Permanent Molars ◽

Secondary Objective ◽

Margin Of Safety

Introduction: The primary concern in the placement of ramal bone screws is the blind nature of the procedure, as there is a thick, mobile layer of soft tissue over the bone; also, the ramus is not a uniplanar structure but is swerving like a propeller blade. The purpose of this study was to evaluate the possibility of establishing clinical guidelines based on visible dental and soft-tissue landmarks for safe, reliable, and accurate insertion of ramal bone screws. Aims and Objectives: Our primary objective was to evaluate the angle formed between the appropriate direction of ramal-implant placement and the line tangential to the buccal surfaces of the first and second permanent molars. Our secondary objective was to evaluate the average distance of the neurovascular bundle from the tip of the bone screw. Materials and Methods: We obtained 80 cone beam computed tomography (CBCT) samples, marked reference lines and points on selected axial and coronal sections, and evaluated the following parameters using the software’s linear- and angular-measurement device: the angle between the appropriate direction of ramal bone screw placement and the line tangential to the buccal surfaces of the first and second permanent molars; and the proximity of the bone screw to the neurovascular bundle. Results: The angle between the constructed line of insertion and the occlusal line, as evaluated from our study, was 19.04 (SD ± 6.89) degrees. The proximity of the neurovascular bundle from the screw is 7.1773 (SD ± 1.73988) mm. Conclusion: We can conclude that ramal bone screws can be placed with a comfortable margin of safety.

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Analysis of Locking Self-Taping Bone Screws for Angularly Stable Plates

Journal of Medical and Biological Engineering ◽

10.1007/s40846-017-0279-4 ◽

2017 ◽

Vol 37 (4) ◽

pp. 612-625 ◽

Cited By ~ 1

Author(s):

Radek Čada ◽

Karel Frydrýšek ◽

František Sejda ◽

Jiří Demel ◽

Leopold Pleva

Keyword(s):

Bone Screws

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Tomographic mapping of buccal shelf area for optimum placement of bone screws: A three-dimensional cone-beam computed tomography evaluation

APOS Trends in Orthodontics ◽

10.25259/apos_20_2019 ◽

2019 ◽

Vol 9 ◽

pp. 241-245

Author(s):

Neeraj Eknath Kolge ◽

Vivek J. Patni ◽

Sheetal S. Potnis

Keyword(s):

Computed Tomography ◽

Cone Beam Computed Tomography ◽

Bone Screws ◽

Neurovascular Bundle ◽

Cone Beam ◽

Shelf Area ◽

Bone Screw ◽

Second Molar ◽

Bone Width ◽

Mandibular Second Molar

Introduction: Buccal shelf bone screws have become increasingly popular as a preferred method of skeletal anchorage in the mandibular arch. Anatomic variations and clinical experience suggest that width and slope of the bone at buccal shelf vary in different population groups, with some individual variations. Aims and Objectives: The objective of this study was to evaluate angulation of the bone screw of mandibular buccal shelf area, total bone width, thickness of the cortical bone, and proximity to neurovascular structures. Materials and Methods: Cone-beam computed tomography scans were used to obtain measurements of the buccal shelf region of 35 patients (18 females, 17 males; mean age, 23.6 years). Measurements were taken at three locations (L1, L2, and L3) and total bone width was measured at two levels from the cementoenamel junction (CEJ, H1 and H2). Bone screws were virtually placed and their proximity evaluated from digitally traced inferior alveolar neurovascular bundle. Results: Permissible angulation for placement of buccal shelf bone screw considering the safety distance from the root and avoiding excessive buccal projection to minimize cheek irritation was found to be 74.48 (SD ± 4.26). Total bone width was maximum at the distobuccal cusp of mandibular second molar (L3H2; 6.40 ± 1.35) when measured at the level of 8 mm from the CEJ. Bone screws were well within the safety range from causing any iatrogenic damage to the inferior alveolar neurovascular bundle at all the three aforementioned locations. Conclusion: Thus, area buccal to the mandibular second molar region seems to be the most favorable site for placement of buccal shelf bone screws in Indian patients.

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