The L1® Midface system is used in particular for the treatment of fractures, fixation of osteotomies, and within the context of reconstructive procedures in the midface area. D min = D maj − 2 ⋅ 5 8 ⋅ H = D maj − 5 3 8 ⋅ P ≈ D maj − 1.082532 ⋅ P D p = D maj − 2 ⋅ 3 8 ⋅ H = D maj − 3 3 8 ⋅ P ≈ D maj − 0.649519 ⋅ P {\displaystyle {\begin{aligned}D_{\text{min}}&=D_{\text{maj}}-2\cdot {\frac {5}{8}}\cdot H=D_{\text{maj}}-{\frac {5{\sqrt {3}}}{8}}\cdot P\approx D_{\text{maj}}-1.082532\cdot P\\[3pt]D_{\text{p}}&=D_{\text{maj}}-2\cdot {\frac {3}{8}}\cdot H=D_{\text{maj}}-{\frac {3{\sqrt {3}}}{8}}\cdot P\approx D_{\text{maj}}-0.649519\cdot P\end{aligned}}} ISO 965-4: Limits of sizes for hot-dip galvanized external screw threads to mate with internal screw threads tapped with tolerance position H or G after galvanizing

A metric ISO screw thread is designated by the letter M followed by the value of the nominal diameter D (the maximum thread diameter) and the pitch P, both expressed in millimetres and separated by a dash or sometimes the multiplication sign, × (e.g. M8-1.25 or M8×1.25). If the pitch is the normally used "coarse" pitch listed in ISO 261 or ISO 262, it can be omitted (e.g. M8). [4] :17 The length of a machine screw or bolt is indicated by an × and the length expressed in millimetres (e.g. M8-1.25×30 or M8×30). [ citation needed] a b ISO 261:1998 ISO general purpose metric screw threads – General plan. International Organization for Standardization. 17 December 1998. The coarse pitch is the commonly used default pitch for a given diameter. In addition, one or two smaller fine pitches are defined, for use in applications where the height of the normal coarse pitch would be unsuitable (e.g. threads in thin-walled pipes). The terms coarse and fine have (in this context) no relation to the manufacturing quality of the thread.All plates are provided with a tab for secure grip, easy placement and full traceability thanks to marked lot numbers on the plates’ surfaces Tables of the derived dimensions for screw diameters and pitches defined in ISO 261 are given in ISO 724. ISO/TC/ 1 Business Plan, 2007-03-05, Version 1.3. Table 3: The market share of each screw thread, p. 7. Use in the repair and the reconstruction of the craniofacial skeleton due to trauma, especially for the osteosynthesis of

The "M" designation for metric screws indicates the nominal outer diameter of the screw thread, in millimetres. This is also referred to as the "major" diameter in the information below. It indicates the diameter of smooth-walled hole that a male thread (e.g. on a bolt) will pass through easily to connect to an internally threaded component (e.g. a nut) on the other side. That is, an M6 screw has a nominal outer diameter of 6 millimetres and will therefore be a well-located, co-axial fit in a hole drilled to 6mm diameter. Final report" (PDF). ntrs.nasa.gov. Archived from the original (PDF) on 14 March 2017 . Retrieved 7 July 2017. The thread values are derived from rounded Renard series. They are defined in ISO 3, with "1st choice" sizes being from the Rˈˈ10 series and "2nd choice" and "3rd choice" sizes being the remaining values from the Rˈˈ20 series. [5]In an external (male) thread (e.g. on a bolt), the major diameter D maj and the minor diameter D min define maximum dimensions of the thread. This means that the external thread must end flat at D maj, but can be rounded out below the minor diameter D min. Conversely, in an internal (female) thread (e.g. in a nut), the major and minor diameters are minimum dimensions; therefore the thread profile must end flat at D min but may be rounded out beyond D maj. In practice this means that one can measure the diameter over the threads of a bolt to find the nominal diameter D maj, and the inner diameter of a nut is D min.

ISO 68-1:1998 ISO general purpose screw threads – Basic profile – Part 1: Metric screw threads. International Organization for Standardization. New and improved bending and cutting instruments with uniform, ergonomic handle design, and spring-loaded closure. The relationship between the height H and the pitch P is found using the following equation where θ is half the included angle of the thread, in this case 30°: [3] H = 1 2 tan ⁡ θ ⋅ P = 3 2 ⋅ P ≈ 0.866025 ⋅ P {\displaystyle H={\frac {1}{2\tan \theta }}\cdot P={\frac {\sqrt {3}}{2}}\cdot P\approx 0.866025\cdot P} Thanks to plate hole countersinks on the both L-plate sides, plates can be either used on the left and the right side of the patient Inventory is considerably reduced Japan has a JIS metric screw thread standard that largely follows the ISO, but with some differences in pitch and head sizes.ISO 965-5: Limits of sizes for internal screw threads to mate with hot-dip galvanized external screw threads with maximum size of tolerance position h before galvanizing