Drilling Capability of Orthodontic Miniscrews: In Vitro Study

Abstract

The aims of this study were to assess the values and mechanical properties of insertion torque (IT) of steel miniscrews inserted in artificial bone blocks (Sawbones, Pacific Research Laboratories, Vashon, WA, USA) with different bone densities and to detect any scratches on the surface of the miniscrews after insertion. Forty self-drilling miniscrews (Leone S.p.A. ø 1.75 mm, L 8 mm) have been inserted into bone blocks that mimic different stability conditions (density: 20 PCF—pounds per cubic foot, 40 PCF, and 30 + 50 PCF with 2 mm and 4 mm of cortical bone). Before insertion and after removal, all miniscrews were inspected with a stereomicroscope 5x and a SEM to detect potential microscopic cracks. Using an electronic surgical motor (W&H Dentalwerk Bürmoos GmbH, Werner Bader Str. 1, 5111 Bürmoos, Austria), the maximum insertion torque value was registered. Stereomicroscope and SEM examination did not indicate any morphological and surface structural changes to the miniscrews, irrespective of the bone density they were inserted into. The findings showed that IT increased significantly with increasing bone density. In each artificial bone block, morphostructural analysis demonstrated the adequate mechanical properties of the self-drilling miniscrews. IT measurements indicated torque values between 6 and 10 Ncm for blocks with a density of 30 + 50 PCF, whereas the suggested values are between 5 and 10 Ncm.

Comparative Assessment of Success Rate Between Silver Nanoparticle Coated and Uncoated Infra-zygomatic Bone Screws: A Split-Mouth Study

“…12 In the current literature the controversy remains regarding the effectiveness of in-vitro studies because of various limitations like the inability to reproduce oral environment, variation in bone density, and also various other hormonal and systemic conditions which will influence the outcome of the study. 13…”

Quantitative Assessment of Posterior Maxillary Arch for Orthodontic Miniscrew Insertion Using Cone Beam Computed Tomography: A Cross-Sectional Analysis

“…Orthodontic miniscrews also known as microscrews, mini-implants, or TADs (temporary anchoring devices) are intraoral devices specifically designed to be mounted within the bones of jaw in order to provide absolute anchorage [ 1 ]. Not needing patient's compliance, today, this technique is widely being used due to its high clinical efficacy, ease of insertion, low cost, and reduction of unwanted movement of other teeth [ 2 , 3 ]. Applications of these devices are mesialization, distalization, extrusion or intrusion of teeth, space opening, and, in some cases, alignment of midline or inclined plane [ 4 , 5 ].…”

“…Cone beam computed tomography (CBCT) is a three-dimensional radiography which can accurately define the shape, morphology, and quantity of the maxillofacial bone [ 14 – 16 ]. This imaging modality presents cross-sectional views which can exactly indicate ridge height and width, concavity, angulation degree, the location and shape of tooth root, distance to anatomic landmarks, and bone density [ 3 , 6 ]. Using CBCT, Haddad et al indicated higher prevalence of miniscrew failure within the posterior maxilla due to reduced cortical bone thickness and suggested more apical insertion of miniscrew in order to access a denser buccolingual and palatal bone level [ 17 ].…”

Quantitative Assessment of Posterior Maxillary Arch for Orthodontic Mini-screw Insertion Using Cone Beam Computed Tomography- a Cross Sectional Analysis

“…Cone beam computed tomography (CBCT) is a three dimensional radiography which can accurately de ne the shape, morphology and quantity of maxillofacial bone (13)(14)(15). This imaging modality presents cross sectional views which can exactly indicate ridge height and width, concavity, angulation degree, the location and shape of tooth root, distance to anatomic landmarks and bone density (3,6). Using CBCT, Haddad et al, indicated higher prevalence of mini-screw failure within posterior maxilla due to reduced cortical bone thickness, and suggested more apical insertion of mini-screw in order to access a denser bucco-lingual and palatal bone level.…”

“…Orthodontic mini-screws also known as micro-screws, mini-implants or TADs (temporary anchoring devices) are intraoral devices speci cally designed to be mounted within the bones of jaw in order to provide absolute anchorage (1). Not needing patient's compliance, today, this technique is widely being used due to its high clinical e cacy, ease of insertion, low cost and reduction of unwanted movement of other teeth (2,3). Application of these devices are, mesialization, distalization, extrusion or intrusion of teeth, space opening and in some cases alignment of midline or inclined plane (4,5).…”