{"id":13664,"date":"2026-07-15T01:58:22","date_gmt":"2026-07-15T01:58:22","guid":{"rendered":"https:\/\/hlh-js.com\/?p=13664"},"modified":"2026-07-15T02:05:13","modified_gmt":"2026-07-15T02:05:13","slug":"sla-surface-treatment-implants-sandblasted-large-grit-acid-etched-process","status":"publish","type":"post","link":"https:\/\/hlh-js.com\/ja\/resource\/blog\/sla-surface-treatment-implants-sandblasted-large-grit-acid-etched-process\/","title":{"rendered":"SLA Surface Treatment for Implants: The Sandblasted Large-Grit Acid-Etched Process \u2014 Parameters, Science, and Clinical Evidence"},"content":{"rendered":"<p><script type=\"application\/ld+json\">{\n    \"@context\": \"https:\\\/\\\/schema.org\",\n    \"@graph\": [\n        {\n            \"@type\": \"Article\",\n            \"headline\": \"SLA Surface Treatment for Implants: The Sandblasted Large-Grit Acid-Etched Process \\u2014 Parameters, Science, and Clinical Evidence\",\n            \"description\": \"Deep-dive technical guide to the SLA (Sandblasted, Large-grit, Acid-etched) implant surface treatment process \\u2014 blasting kinetics, crater formation, acid etch chemistry, dual-scale roughness quantification, clinical osseointegration data, and comparison with TPS, HA, and laser surface treatments.\",\n            \"datePublished\": \"2026-07-13\",\n            \"dateModified\": \"2026-07-13\",\n            \"author\": {\n                \"@type\": \"Organization\",\n                \"name\": \"Jiangsu Henglihong Technology Co., Ltd.\",\n                \"url\": \"https:\\\/\\\/hlh-js.com\\\/\"\n            },\n            \"publisher\": {\n                \"@type\": \"Organization\",\n                \"name\": \"Jiangsu Henglihong Technology Co., Ltd.\",\n                \"logo\": {\n                    \"@type\": \"ImageObject\",\n                    \"url\": \"https:\\\/\\\/hlh-js.com\\\/wp-content\\\/uploads\\\/hlh-logo.png\"\n                }\n            },\n            \"mainEntityOfPage\": {\n                \"@type\": \"WebPage\",\n                \"@id\": \"https:\\\/\\\/hlh-js.com\\\/resource\\\/blog\\\/sla-surface-treatment-implants-sandblasted-large-grit-acid-etched-process\\\/\"\n            }\n        },\n        {\n            \"@type\": \"FAQPage\",\n            \"mainEntity\": [\n                {\n                    \"@type\": \"Question\",\n                    \"name\": \"What does 'large grit' mean in SLA surface treatment?\",\n                    \"acceptedAnswer\": {\n                        \"@type\": \"Answer\",\n                        \"text\": \"'Large grit' in the SLA name refers to the particle size of the blasting media used \\u2014 specifically aluminum oxide particles in the 250\\u2013500 \\u03bcm range, which were described as 'large' relative to the finer media (50\\u2013150 \\u03bcm) used in earlier implant blasting protocols. The large particle size is functionally important: impact craters from 250\\u2013500 \\u03bcm particles are 5\\u201320 \\u03bcm in diameter, creating macro-scale surface features sized to accommodate osteoprogenitor cells (20\\u201330 \\u03bcm diameter) and provide mechanical interlocking for fibrin clot organization. Smaller particles produce finer roughness that lacks the macro-scale tissue scaffolding effect.\"\n                    }\n                },\n                {\n                    \"@type\": \"Question\",\n                    \"name\": \"What is the acid etch chemistry in the SLA process?\",\n                    \"acceptedAnswer\": {\n                        \"@type\": \"Answer\",\n                        \"text\": \"Standard SLA acid etching uses a mixture of hydrochloric acid (HCl) and sulfuric acid (H\\u2082SO\\u2084) at concentrations and temperatures that are proprietary to each implant manufacturer but are typically in the range of 1:1 to 3:1 volume ratio HCl:H\\u2082SO\\u2084 at temperatures of 60\\u201380\\u00b0C, with immersion times of 5\\u201330 minutes. The HCl dissolves the native TiO\\u2082 passive layer and preferentially attacks titanium grain boundaries, creating micro-pitting at the sub-micrometer scale. The H\\u2082SO\\u2084 intensifies the etch rate and dissolves the work-hardened zone. The combined effect is removal of the blasting-induced deformation layer and creation of a second (micro) scale of roughness superimposed on the blast-created macro-roughness.\"\n                    }\n                },\n                {\n                    \"@type\": \"Question\",\n                    \"name\": \"How does SLA compare to titanium plasma spray (TPS) for osseointegration?\",\n                    \"acceptedAnswer\": {\n                        \"@type\": \"Answer\",\n                        \"text\": \"Both SLA and titanium plasma spray (TPS) produce surfaces capable of strong osseointegration, but through different mechanisms. TPS creates a macro-porous coating (Ra 40\\u201380 \\u03bcm, pore size 100\\u2013400 \\u03bcm) that allows deep bone ingrowth into the inter-particle spaces \\u2014 a three-dimensional mechanical interlock. SLA creates a controlled dual-scale texture (Ra 1\\u20132 \\u03bcm post-etch) that promotes cell-level biological osseointegration across the full implant surface area. Clinical comparisons show similar long-term osseointegration quality, but SLA surfaces achieve osseointegration faster (4\\u20136 weeks vs 8\\u201312 weeks for TPS in most bone types) due to the more immediate cell-surface interaction. SLA is also dimensionally more precise \\u2014 the TPS coating adds 50\\u2013200 \\u03bcm to implant dimensions that must be designed in.\"\n                    }\n                },\n                {\n                    \"@type\": \"Question\",\n                    \"name\": \"What is the difference between SLA for dental versus orthopedic implants?\",\n                    \"acceptedAnswer\": {\n                        \"@type\": \"Answer\",\n                        \"text\": \"The fundamental SLA process is the same for dental and orthopedic applications, but the specific parameters differ. Dental implant SLA typically uses 250\\u2013500 \\u03bcm Al\\u2082O\\u2083 at 2\\u20134 bar and targets post-etch Ra of 1\\u20132 \\u03bcm. Orthopedic SLA blasting often uses larger media (500\\u2013750 \\u03bcm) at higher pressure (4\\u20136 bar) to achieve Ra 2\\u20134 \\u03bcm on the harder Ti-6Al-4V substrate, targeting the rougher surface range that provides mechanical bone interlocking in higher-load orthopedic environments. The acid etch step for orthopedic applications may be more aggressive to remove the thicker work-hardened zone created by higher-energy blasting. Both applications target hierarchical dual-scale roughness, but calibrated to the different biological demands of the anatomical environment.\"\n                    }\n                },\n                {\n                    \"@type\": \"Question\",\n                    \"name\": \"Can laser surface treatment replace SLA for implants?\",\n                    \"acceptedAnswer\": {\n                        \"@type\": \"Answer\",\n                        \"text\": \"Laser surface treatment \\u2014 using pulsed laser ablation to create controlled micro- and nano-scale surface features \\u2014 has been investigated as an alternative to SLA for implant surface treatment. Laser texturing offers precise, reproducible surface geometry without media contamination concerns, and can create specific topographic patterns (grooves, pits, pillars) at defined scales. However, clinical evidence supporting laser-textured implant surfaces is far less extensive than for SLA. SLA remains the gold standard with decades of clinical data from millions of implants. Laser texturing is used commercially on some implant systems as a complement to or modification of blasted surfaces, but has not replaced SLA as the dominant surface treatment process in the industry.\"\n                    }\n                }\n            ]\n        }\n    ]\n}<\/script> <style>\r\n.hlh-sla*,.hlh-sla*::before,.hlh-sla*::after{box-sizing:border-box;margin:0;padding:0}\r\n.hlh-sla{font-family:'Segoe UI',Arial,sans-serif;font-size:16px;line-height:1.78;color:#1e2a38;max-width:860px;margin:0 auto;padding:0 20px 64px}\r\n.hlh-sla h1{font-size:clamp(1.65rem,3.5vw,2.2rem);font-weight:800;color:#1a3456;line-height:1.22;margin-bottom:20px}\r\n.hlh-sla h2{font-size:clamp(1.18rem,2.5vw,1.46rem);font-weight:700;color:#1a3456;border-left:4px solid #d86e18;padding-left:14px;margin:50px 0 16px}\r\n.hlh-sla h3{font-size:1.05rem;font-weight:700;color:#1a3456;margin:28px 0 10px}\r\n.hlh-sla p{margin-bottom:16px}\r\n.hlh-sla ul,.hlh-sla 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a{display:inline-block;background:#d86e18;color:#fff;font-weight:700;padding:13px 30px;border-radius:5px;font-size:.96rem;text-decoration:none}\r\n.hlh-sla-cta a:hover{background:#b85c12;text-decoration:none}\r\n@media(max-width:600px){.hlh-sla-hero,.hlh-sla-cta{padding:26px 18px}.hlh-sla-phases{grid-template-columns:1fr}}\r\n<\/style><\/p>\r\n<div class=\"hlh-sla\"><a class=\"hlh-sla-back\" href=\"https:\/\/hlh-js.com\/resource\/blog\/abrasive-blasting-surface-treatment-medical-devices\/\" target=\"_blank\" rel=\"noopener noreferrer\">\u2190 Abrasive Blasting for Medical Devices: Complete Guide<\/a>\r\n<h1>SLA Surface Treatment for Implants: The Sandblasted Large-Grit Acid-Etched Process \u2014 Parameters, Science, and Clinical Evidence<\/h1>\r\n<div class=\"hlh-sla-hero\">\r\n<div class=\"hlh-sla-hero-tag\">In-Depth Guide \u00b7 Medical Device Series \u00b7 C09<\/div>\r\n<p>The SLA process is the most consequential surface treatment innovation in implant history. In the three decades since its clinical introduction, it has been applied to hundreds of millions of dental and orthopedic implants, validated in thousands of controlled clinical trials, and set the benchmark against which every new implant surface must be measured. Yet despite this ubiquity, the physics and chemistry of SLA \u2014 why the two-step sequence of blasting followed by acid etching produces a surface so consistently superior to either treatment alone \u2014 is rarely explained at the mechanistic level. This guide fills that gap. It covers the kinetics of particle impact and crater formation, the grain boundary chemistry of acid etching, the dual-scale roughness quantification methods that characterize the result, and the clinical evidence base that has established SLA as the gold standard it is.<\/p>\r\n<\/div>\r\n<nav class=\"hlh-sla-toc\" aria-label=\"\u76ee\u6b21\">\r\n<div class=\"hlh-sla-toc-label\">Table of Contents<\/div>\r\n<ol>\r\n<li><a href=\"#sl-origin\">Origin and Rationale of the SLA Concept<\/a><\/li>\r\n<li><a href=\"#sl-blast-physics\">Phase 1 \u2014 Blasting: Particle Kinetics, Impact Mechanics, and Crater Formation<\/a><\/li>\r\n<li><a href=\"#sl-etch-physics\">Phase 2 \u2014 Acid Etching: Grain Boundary Attack and Micro-Pit Formation<\/a><\/li>\r\n<li><a href=\"#sl-dual\">Dual-Scale Roughness: Quantification by Profilometry, AFM, and SEM<\/a><\/li>\r\n<li><a href=\"#sl-cell\">How Dual-Scale Roughness Drives Osseointegration<\/a><\/li>\r\n<li><a href=\"#sl-variants\">SLA Variants: SLActive, Hydrophilic Modifications, and Proprietary Systems<\/a><\/li>\r\n<li><a href=\"#sl-vs\">SLA vs TPS, HA Coating, and Laser Surface Treatment<\/a><\/li>\r\n<li><a href=\"#sl-params\">Dental vs Orthopedic SLA: Parameter Differences<\/a><\/li>\r\n<li><a href=\"#sl-control\">Process Control Points and Validation Requirements<\/a><\/li>\r\n<li><a href=\"#sl-faq\">\u3088\u304f\u3042\u308b\u8cea\u554f<\/a><\/li>\r\n<\/ol>\r\n<\/nav>\r\n<h2 id=\"sl-origin\">1. Origin and Rationale of the SLA Concept<\/h2>\r\n<p>By the mid-1980s, two independent lines of research had established that titanium surface roughness significantly influenced early bone formation at the implant interface. Animal studies comparing machined (turned) titanium implants with roughened versions showed consistently higher bone-to-implant contact (BIC) ratios for roughened surfaces at early time points (2\u20134 weeks). The mechanism was not yet fully understood, but the practical implication was clear: the smooth, turned surface that machining produces is not optimal for osseointegration.<\/p>\r\n<p>The question was how to create that roughness in a controlled, reproducible way that could be validated for clinical use. Two candidate processes existed: blasting (which created macro-roughness efficiently but left a work-hardened surface layer of uncertain biocompatibility) and acid etching (which created micro-roughness but no macro-scale features). The SLA insight was that these processes were synergistic rather than competitive \u2014 blasting first to create macro features, then etching to create micro features and simultaneously remove the blasting-induced surface artifacts, produced a surface with dual-scale roughness at both scales that cells could respond to simultaneously. The clinical validation of this hypothesis through controlled trials in the 1990s established SLA as the dominant implant surface treatment globally.<\/p>\r\n<h2 id=\"sl-blast-physics\">2. Phase 1 \u2014 Blasting: Particle Kinetics, Impact Mechanics, and Crater Formation<\/h2>\r\n<p>Understanding the physics of the blasting phase requires considering what happens during the approximately 10\u2013100 microseconds of a single particle impact event.<\/p>\r\n<h3>Particle Velocity and Kinetic Energy<\/h3>\r\n<p>In a pressure-blast system at 3 bar, 250\u2013500 \u03bcm Al\u2082O\u2083 particles are accelerated through the nozzle to velocities of approximately 50\u2013150 m\/s, depending on particle mass, nozzle geometry, and air pressure. The kinetic energy of a single particle is proportional to \u00bdmv\u00b2 \u2014 a 300 \u03bcm Al\u2082O\u2083 particle (density ~3.95 g\/cm\u00b3) at 100 m\/s carries approximately 0.56 \u03bcJ of kinetic energy. While this seems tiny, it is concentrated over the ~50 \u03bcm\u00b2 contact area of the particle tip, creating a local contact pressure of approximately 10\u201330 GPa during impact \u2014 far exceeding the yield strength of both the particle and the titanium substrate.<\/p>\r\n<h3>Impact Mechanics and Crater Geometry<\/h3>\r\n<p>Upon impact, both the Al\u2082O\u2083 particle and the titanium surface deform. The titanium surface deforms plastically to create an impact crater whose geometry is determined by the particle shape, velocity, and impact angle. Angular Al\u2082O\u2083 particles create asymmetric craters with sharp ridges between impacts \u2014 the characteristic &#8220;peaky&#8221; morphology of blasted titanium surfaces seen by SEM. These crater geometries have specific dimensions: crater diameter approximately 0.5\u20132\u00d7 the particle diameter (125\u20131000 \u03bcm for 250\u2013500 \u03bcm particles), crater depth approximately 5\u201320% of particle diameter (12\u2013100 \u03bcm). The macro-roughness created by these overlapping craters \u2014 Ra 2\u20134 \u03bcm for standard SLA blasting parameters \u2014 represents the macroscale of the dual-scale surface.<\/p>\r\n<h3>Work-Hardening and Residual Stress<\/h3>\r\n<p>Beneath each crater, a work-hardened zone extends 5\u201330 \u03bcm into the substrate with elevated dislocation density, increased hardness, and biaxial compressive residual stress. The work-hardened zone has a different etch response than undeformed titanium \u2014 it etches faster and with different morphology. The SLA acid etch step removes this layer completely, which is why etch time and temperature are critical process parameters: under-etching leaves work-hardened material that would produce different micro-pit morphology than specified; over-etching removes the macro-roughness peaks.<\/p>\r\n<h2 id=\"sl-etch-physics\">3. Phase 2 \u2014 Acid Etching: Grain Boundary Attack and Micro-Pit Formation<\/h2>\r\n<p>The acid etching phase acts on the work-hardened, macro-rough blasted surface to create a second (micro) scale of roughness while simultaneously removing the blasting artifacts. The chemistry of HCl\/H\u2082SO\u2084 etching of titanium operates through two parallel mechanisms:<\/p>\r\n<h3>Grain Boundary Etching<\/h3>\r\n<p>Titanium&#8217;s hexagonal close-packed (HCP) crystal structure at room temperature (alpha phase) contains grain boundaries \u2014 the interfaces between differently oriented crystal grains that are several micrometers across. Grain boundaries have higher chemical reactivity than grain interiors because the crystal structure is disrupted at the boundary, increasing the local free energy. HCl attacks grain boundaries preferentially, dissolving titanium faster along these interfaces than across grain faces. The result is a network of micro-grooves following the grain boundary geometry, creating pits 0.5\u20133 \u03bcm deep and 1\u20135 \u03bcm across \u2014 the micro-scale of the SLA dual-scale surface.<\/p>\r\n<h3>Work-Hardened Layer Removal<\/h3>\r\n<p>The work-hardened surface layer introduced by blasting has elevated dislocation density, which also increases chemical reactivity relative to the undisturbed bulk material. The acid preferentially dissolves this layer, acting to remove the blasting artifacts \u2014 the compressed, smeared surface that would otherwise present a different biological surface to cells than the intended grain-boundary micro-pitted texture beneath. Complete removal of the work-hardened layer is confirmed in SEM cross-sections by the absence of a distinct deformation zone at the surface, and by the change in Ra from approximately 3 \u03bcm (post-blast) to 1\u20132 \u03bcm (post-etch) as the sharp blast-created peaks are rounded and partially dissolved.<\/p>\r\n<h3>Alumina Particle Dissolution<\/h3>\r\n<p>HCl\/H\u2082SO\u2084 also dissolves surface-adhered Al\u2082O\u2083 blasting media particles, reducing (though not eliminating) the alumina contamination introduced by blasting. The dissolution rate of Al\u2082O\u2083 in HCl is lower than that of titanium under these conditions, which is why extended etching can reduce but not eliminate embedded alumina in the first 1\u20135 \u03bcm of the surface. This limitation is the primary driver of the shift to TiO\u2082 and ZrO\u2082 blasting media.<\/p>\r\n<h2 id=\"sl-dual\">4. Dual-Scale Roughness: Quantification by Profilometry, AFM, and SEM<\/h2>\r\n<p>The defining characteristic of the SLA surface \u2014 and the property most directly linked to its clinical superiority over single-treatment surfaces \u2014 is the dual-scale roughness hierarchy. Quantifying both scales requires multiple complementary characterization methods.<\/p>\r\n<div class=\"hlh-sla-phases\">\r\n<div class=\"hlh-sla-phase\">\r\n<h3>Macro-Scale (From Blasting)<\/h3>\r\n<ul>\r\n<li>Ra 2\u20134 \u03bcm (before etch)<\/li>\r\n<li>Feature size: 5\u201320 \u03bcm diameter craters<\/li>\r\n<li>Characterized by: contact profilometry (ISO 4287), cutoff \u03bbc 0.8 mm<\/li>\r\n<li>SEM magnification: \u00d7100\u2013\u00d7500<\/li>\r\n<li>Biological relevance: fibrin clot anchoring, osteoprogenitor cell migration scaffold<\/li>\r\n<\/ul>\r\n<\/div>\r\n<div class=\"hlh-sla-phase\">\r\n<h3>Micro-Scale (From Acid Etching)<\/h3>\r\n<ul>\r\n<li>Ra 0.5\u20131.5 \u03bcm (post-etch measurement with \u03bbc 0.08 mm)<\/li>\r\n<li>Feature size: 0.5\u20135 \u03bcm diameter pits<\/li>\r\n<li>Characterized by: optical profilometry (ISO 25178), AFM<\/li>\r\n<li>SEM magnification: \u00d72000\u2013\u00d710000<\/li>\r\n<li>Biological relevance: individual integrin receptor engagement, osteogenic differentiation signaling<\/li>\r\n<\/ul>\r\n<\/div>\r\n<\/div>\r\n<p>The three-dimensional characterization parameters from ISO 25178 areal surface texture are increasingly important for SLA surface specification. Sdr (developed interfacial area ratio) quantifies the actual surface area increase relative to a flat plane \u2014 SLA surfaces typically show Sdr values of 30\u201380%, meaning the cell-available surface area is 30\u201380% greater than the projected footprint area. Ssk (skewness) characterizes whether the surface has predominantly peaks or valleys: SLA surfaces typically show negative Ssk (valley-dominated texture created by acid-etched pits), which is associated with better osteoblast spreading than peak-dominated (positive Ssk) surfaces.<\/p>\r\n<h2 id=\"sl-cell\">5. How Dual-Scale Roughness Drives Osseointegration<\/h2>\r\n<p>The clinical superiority of SLA over single-treatment surfaces emerges from the way the two roughness scales engage different biological processes at different organizational levels during bone healing:<\/p>\r\n<p><strong>Macro-scale (2\u20134 \u03bcm Ra) effects:<\/strong> At the scale of tissue organization, the macro-rough blasted surface creates a three-dimensional mechanical scaffold for fibrin clot organization in the peri-implant gap. The clot \u2014 which bridges the gap between implant surface and bleeding bone \u2014 must anchor to the implant surface to resist displacement under early loading. The 5\u201320 \u03bcm crater geometry of the blasted surface provides interlocking sites for fibrin fibers, maintaining clot stability during the critical first 72 hours when mesenchymal stem cells migrate through the clot toward the implant surface. A smooth surface provides no clot anchoring; a macro-rough SLA surface provides abundant anchoring geometry at the fibrin fiber scale.<\/p>\r\n<p><strong>Micro-scale (0.5\u20131.5 \u03bcm Ra) effects:<\/strong> At the cellular level, osteoprogenitor cells arriving at the implant surface probe the surface topography with focal adhesion complexes \u2014 clusters of integrin receptors spanning approximately 50\u2013200 nm individually, grouped in assemblies of 0.5\u20135 \u03bcm scale. The micro-pits created by acid etching are precisely in the size range of focal adhesion complexes, providing the geometric features that maximally engage integrin-mediated mechanosensing. This mechanosensing triggers intracellular signaling (primarily through the FAK-MAPK pathway) that upregulates osteogenic transcription factors and commits the cell to osteoblast differentiation rather than fibroblast differentiation.<\/p>\r\n<h2 id=\"sl-variants\">6. SLA Variants: SLActive, Hydrophilic Modifications, and Proprietary Systems<\/h2>\r\n<div class=\"hlh-sla-table-wrap\">\r\n<table class=\"hlh-sla-table\">\r\n<thead>\r\n<tr>\r\n<th>Surface<\/th>\r\n<th>Manufacturer<\/th>\r\n<th>SLA Modification<\/th>\r\n<th>Clinical Advantage<\/th>\r\n<\/tr>\r\n<\/thead>\r\n<tbody>\r\n<tr>\r\n<td>SLActive<\/td>\r\n<td>Straumann<\/td>\r\n<td>Post-etch handling under N\u2082; stored in isotonic NaCl. Hydrophilic surface.<\/td>\r\n<td>Higher ISQ at 2\u20134 weeks; enables 4-week loading protocol in good bone<\/td>\r\n<\/tr>\r\n<tr>\r\n<td>Ossean<\/td>\r\n<td>Intralock<\/td>\r\n<td>SLA + vacuum-driven Ca\/P ion impregnation<\/td>\r\n<td>Enhanced bioactivity; better performance in compromised\/low-density bone<\/td>\r\n<\/tr>\r\n<tr>\r\n<td>OsseoSpeed<\/td>\r\n<td>Dentsply Sirona<\/td>\r\n<td>TiO\u2082 blasting (no Al) + dilute HF etch; fluoride-modified surface<\/td>\r\n<td>Fluoride incorporation promotes osteoblast differentiation; good in low-density bone<\/td>\r\n<\/tr>\r\n<tr>\r\n<td>Laser-Lok<\/td>\r\n<td>BioHorizons<\/td>\r\n<td>Laser microtexturing (not SLA) on collar zone; SLA-equivalent on body<\/td>\r\n<td>Crestal bone maintenance claim through epithelial\/connective tissue attachment at collar<\/td>\r\n<\/tr>\r\n<tr>\r\n<td>Roxolid SLActive<\/td>\r\n<td>Straumann<\/td>\r\n<td>SLActive process on Ti-Zr alloy<\/td>\r\n<td>Smaller-diameter implants with equivalent osseointegration to standard-diameter Ti<\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n<\/div>\r\n<h2 id=\"sl-vs\">7. SLA vs TPS, HA Coating, and Laser Surface Treatment<\/h2>\r\n<div class=\"hlh-sla-table-wrap\">\r\n<table class=\"hlh-sla-table\">\r\n<thead>\r\n<tr>\r\n<th>\u8868\u9762\u51e6\u7406<\/th>\r\n<th>Ra \/ Scale<\/th>\r\n<th>Osseointegration Speed<\/th>\r\n<th>Long-term Stability<\/th>\r\n<th>Manufacturing Complexity<\/th>\r\n<th>Contamination Risk<\/th>\r\n<\/tr>\r\n<\/thead>\r\n<tbody>\r\n<tr>\r\n<td>SLA<\/td>\r\n<td>1\u20132 \u03bcm (dual-scale)<\/td>\r\n<td>4\u20136 weeks<\/td>\r\n<td>Excellent (decades of data)<\/td>\r\n<td>Medium (2 controlled steps)<\/td>\r\n<td>Al contamination if Al\u2082O\u2083 media; manageable<\/td>\r\n<\/tr>\r\n<tr>\r\n<td>Titanium Plasma Spray (TPS)<\/td>\r\n<td>40\u201380 \u03bcm Ra; porous<\/td>\r\n<td>6\u201312 weeks<\/td>\r\n<td>Good (risk of coating delamination long-term)<\/td>\r\n<td>High (plasma spray equipment, QC)<\/td>\r\n<td>\u4f4e\u3044<\/td>\r\n<\/tr>\r\n<tr>\r\n<td>HA Plasma Spray<\/td>\r\n<td>50\u2013100 \u03bcm Ra; porous HA<\/td>\r\n<td>4\u20136 weeks (faster in poor bone)<\/td>\r\n<td>HA dissolves over 5\u201310 years; bone fills void<\/td>\r\n<td>High (ASTM F1609 compliance)<\/td>\r\n<td>HA resorption creates void; variable<\/td>\r\n<\/tr>\r\n<tr>\r\n<td>Acid-etch only (no blast)<\/td>\r\n<td>0.5\u20131.5 \u03bcm (micro only)<\/td>\r\n<td>6\u201310 weeks<\/td>\r\n<td>Good where bone contact uniform<\/td>\r\n<td>Low (single step)<\/td>\r\n<td>\u4f4e\u3044<\/td>\r\n<\/tr>\r\n<tr>\r\n<td>Laser ablation<\/td>\r\n<td>Programmable; 1\u201350 \u03bcm<\/td>\r\n<td>4\u20138 weeks (limited data)<\/td>\r\n<td>Promising but less clinical data<\/td>\r\n<td>Medium-High (laser equipment, programming)<\/td>\r\n<td>None (no media contact)<\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n<\/div>\r\n<h2 id=\"sl-params\">8. Dental vs Orthopedic SLA: Parameter Differences<\/h2>\r\n<div class=\"hlh-sla-table-wrap\">\r\n<table class=\"hlh-sla-table\">\r\n<thead>\r\n<tr>\r\n<th>\u30d1\u30e9\u30e1\u30fc\u30bf<\/th>\r\n<th>Dental SLA<\/th>\r\n<th>Orthopedic SLA<\/th>\r\n<th>Reason for Difference<\/th>\r\n<\/tr>\r\n<\/thead>\r\n<tbody>\r\n<tr>\r\n<td>Substrate material<\/td>\r\n<td>CP-Ti or Ti-6Al-4V<\/td>\r\n<td>Ti-6Al-4V ELI primarily<\/td>\r\n<td>Different hardness response<\/td>\r\n<\/tr>\r\n<tr>\r\n<td>Blast media size<\/td>\r\n<td>250\u2013500 \u03bcm<\/td>\r\n<td>250\u2013750 \u03bcm<\/td>\r\n<td>Larger Ra target for orthopedic bone ingrowth<\/td>\r\n<\/tr>\r\n<tr>\r\n<td>Blast pressure<\/td>\r\n<td>2\u20134 bar<\/td>\r\n<td>3.5\u20136 bar<\/td>\r\n<td>Harder substrate requires more energy<\/td>\r\n<\/tr>\r\n<tr>\r\n<td>Post-blast Ra target<\/td>\r\n<td>2\u20134 \u03bcm<\/td>\r\n<td>2.5\u20135 \u03bcm<\/td>\r\n<td>Rougher surface for mechanical interlocking<\/td>\r\n<\/tr>\r\n<tr>\r\n<td>Acid etch conditions<\/td>\r\n<td>Standard HCl\/H\u2082SO\u2084, 5\u201315 min<\/td>\r\n<td>More aggressive; longer dwell<\/td>\r\n<td>Deeper work-hardened zone to remove<\/td>\r\n<\/tr>\r\n<tr>\r\n<td>Post-etch Ra target<\/td>\r\n<td>1\u20132 \u03bcm<\/td>\r\n<td>2\u20134 \u03bcm<\/td>\r\n<td>Orthopedic retains more macro-roughness<\/td>\r\n<\/tr>\r\n<tr>\r\n<td>Post-etch treatment<\/td>\r\n<td>Rinse, dry or store in NaCl (SLActive)<\/td>\r\n<td>Often followed by HA\/TPS coating<\/td>\r\n<td>Different fixation strategy<\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n<\/div>\r\n<h2 id=\"sl-control\">9. Process Control Points and Validation Requirements<\/h2>\r\n<p>The SLA process has multiple critical control points where deviation can produce surfaces outside specification. Under ISO 13485, each control point must be identified in the process FMEA, its acceptable range defined in the process specification, and monitoring\/control measures implemented in production.<\/p>\r\n<ul>\r\n<li><strong>Blasting media particle size distribution:<\/strong> Verified by sieve analysis at incoming inspection and at defined change intervals. Specification: maximum percentage outside the 250\u2013500 \u03bcm (or application-specific) range.<\/li>\r\n<li><strong>Blast pressure:<\/strong> Measured and recorded per batch; controlled by pressure regulator with defined \u00b1tolerance (typically \u00b10.3 bar).<\/li>\r\n<li><strong>Post-blast Ra:<\/strong> Measured on production samples or control coupons per lot; must fall within the validated Ra range before proceeding to acid etch.<\/li>\r\n<li><strong>Acid bath concentration:<\/strong> Titrated at defined intervals; acid change interval defined by production lot count or pH drift.<\/li>\r\n<li><strong>Acid etch temperature and time:<\/strong> Temperature monitored by calibrated thermocouple; time controlled by validated timer with process record.<\/li>\r\n<li><strong>Post-etch Ra:<\/strong> Measured on sampling basis; must fall within specification (1\u20132 \u03bcm for dental, 2\u20134 \u03bcm for orthopedic).<\/li>\r\n<li><strong>Post-etch cleaning and drying:<\/strong> DI water quality (resistivity), rinse duration, and drying conditions must be controlled to prevent recontamination or hydrophilic surface degradation.<\/li>\r\n<\/ul>\r\n<div class=\"hlh-sla-related\">\r\n<h3>Related Guides in This Series<\/h3>\r\n<a href=\"https:\/\/hlh-js.com\/resource\/blog\/abrasive-blasting-dental-implants-sla-surface-treatment-process\/\" target=\"_blank\" rel=\"noopener noreferrer\">\u2192 Dental Implant SLA Surface Treatment: Application Guide<\/a> <a href=\"https:\/\/hlh-js.com\/resource\/blog\/abrasive-blasting-orthopedic-implants-bone-ingrowth-surface-preparation\/\" target=\"_blank\" rel=\"noopener noreferrer\">\u2192 Orthopedic Implant Surface Preparation Guide<\/a> <a href=\"https:\/\/hlh-js.com\/resource\/blog\/surface-roughness-medical-implants-ra-sa-osseointegration-specifications\/\" target=\"_blank\" rel=\"noopener noreferrer\">\u2192 Surface Roughness for Medical Implants: Ra, Sa, and Specifications<\/a> <a href=\"https:\/\/hlh-js.com\/resource\/blog\/abrasive-blasting-titanium-medical-implants-media-selection-alumina-contamination\/\" target=\"_blank\" rel=\"noopener noreferrer\">\u2192 Titanium Medical Implants: Media Selection and Alumina Contamination<\/a> <a href=\"https:\/\/hlh-js.com\/resource\/blog\/abrasive-blasting-surface-treatment-medical-devices\/\" target=\"_blank\" rel=\"noopener noreferrer\">\u2190 Complete Guide: Abrasive Blasting for Medical Devices<\/a><\/div>\r\n<h2 id=\"sl-faq\">10. Frequently Asked Questions<\/h2>\r\n<div>\r\n<div class=\"hlh-sla-faq-item\"><button class=\"hlh-sla-faq-btn\" aria-expanded=\"false\" aria-controls=\"slq1\">What does &#8216;large grit&#8217; mean in SLA?<span class=\"hlh-sla-faq-icon\">+<\/span><\/button>\r\n<div id=\"slq1\" class=\"hlh-sla-faq-answer\">\r\n<p>&#8216;Large grit&#8217; refers to Al\u2082O\u2083 particles in the 250\u2013500 \u03bcm range \u2014 described as large relative to earlier finer media (50\u2013150 \u03bcm). The large particle size creates impact craters 5\u201320 \u03bcm in diameter, sized to accommodate osteoprogenitor cells (20\u201330 \u03bcm) and provide mechanical interlocking for fibrin clot organization. Smaller particles produce finer roughness that lacks the macro-scale tissue scaffolding effect that makes SLA clinically superior to micro-only surfaces.<\/p>\r\n<\/div>\r\n<\/div>\r\n<div class=\"hlh-sla-faq-item\"><button class=\"hlh-sla-faq-btn\" aria-expanded=\"false\" aria-controls=\"slq2\">What is the acid etch chemistry in the SLA process?<span class=\"hlh-sla-faq-icon\">+<\/span><\/button>\r\n<div id=\"slq2\" class=\"hlh-sla-faq-answer\">\r\n<p>Standard SLA acid etching uses a mixture of HCl and H\u2082SO\u2084 at concentrations typically in the 1:1 to 3:1 HCl:H\u2082SO\u2084 volume ratio, at 60\u201380\u00b0C for 5\u201330 minutes (exact conditions proprietary to each manufacturer). HCl attacks titanium grain boundaries, creating micro-pits 0.5\u20133 \u03bcm deep. H\u2082SO\u2084 intensifies etching and dissolves the work-hardened zone. The combination removes blasting artifacts and creates the micro-scale roughness superimposed on the blast macro-roughness.<\/p>\r\n<\/div>\r\n<\/div>\r\n<div class=\"hlh-sla-faq-item\"><button class=\"hlh-sla-faq-btn\" aria-expanded=\"false\" aria-controls=\"slq3\">How does SLA compare to titanium plasma spray?<span class=\"hlh-sla-faq-icon\">+<\/span><\/button>\r\n<div id=\"slq3\" class=\"hlh-sla-faq-answer\">\r\n<p>Both achieve strong osseointegration through different mechanisms. TPS creates macro-porous coating (Ra 40\u201380 \u03bcm) for deep bone ingrowth; SLA creates a 1\u20132 \u03bcm dual-scale surface for cell-level biological osseointegration. SLA achieves osseointegration faster (4\u20136 weeks vs 8\u201312 weeks for TPS), is dimensionally more precise (no added coating thickness), and is less susceptible to coating delamination. TPS is used where deep mechanical bone interlocking is specifically desired and its dimensional tolerance is designed into the implant.<\/p>\r\n<\/div>\r\n<\/div>\r\n<div class=\"hlh-sla-faq-item\"><button class=\"hlh-sla-faq-btn\" aria-expanded=\"false\" aria-controls=\"slq4\">What is the difference between SLA for dental vs orthopedic implants?<span class=\"hlh-sla-faq-icon\">+<\/span><\/button>\r\n<div id=\"slq4\" class=\"hlh-sla-faq-answer\">\r\n<p>The process is the same but parameters differ. Dental: 250\u2013500 \u03bcm Al\u2082O\u2083, 2\u20134 bar, post-etch Ra 1\u20132 \u03bcm. Orthopedic: 250\u2013750 \u03bcm Al\u2082O\u2083, 3.5\u20136 bar (harder Ti-6Al-4V substrate), post-etch Ra 2\u20134 \u03bcm (rougher target for bone ingrowth in higher-load environment). Orthopedic SLA is often followed by HA plasma spray over the blasted substrate, while dental SLA is typically the final roughening step.<\/p>\r\n<\/div>\r\n<\/div>\r\n<div class=\"hlh-sla-faq-item\"><button class=\"hlh-sla-faq-btn\" aria-expanded=\"false\" aria-controls=\"slq5\">Can laser surface treatment replace SLA?<span class=\"hlh-sla-faq-icon\">+<\/span><\/button>\r\n<div id=\"slq5\" class=\"hlh-sla-faq-answer\">\r\n<p>Not yet as a replacement for SLA as the global standard. Laser texturing offers precise, media-contamination-free surface creation with programmable geometry, and is used commercially on some implant systems. However, clinical evidence for laser-textured surfaces is far less extensive than for SLA. SLA has decades of data from millions of implants; laser texturing is emerging technology used as a complement to or modification of SLA in some systems. The industry consensus remains that SLA is the benchmark surface treatment.<\/p>\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n<div class=\"hlh-sla-cta\">\r\n<h2>Source Medical-Grade Blasting Media for SLA Process Production<\/h2>\r\n<p>Jiangsu Henglihong Technology supplies aluminum oxide and titanium dioxide blasting media in SLA-grade specifications, with particle size distribution data, purity certificates, and process validation support documentation.<\/p>\r\n<a href=\"https:\/\/hlh-js.com\/contact\/\" target=\"_blank\" rel=\"noopener noreferrer\">Request SLA Media Specifications &amp; Quote<\/a><\/div>\r\n<\/div>\r\n<p><script>(function(){var b=document.querySelectorAll('.hlh-sla-faq-btn');b.forEach(function(btn){btn.addEventListener('click',function(){var e=this.getAttribute('aria-expanded')==='true',a=document.getElementById(this.getAttribute('aria-controls'));b.forEach(function(x){x.setAttribute('aria-expanded','false');var y=document.getElementById(x.getAttribute('aria-controls'));if(y)y.style.maxHeight='0'});if(!e){this.setAttribute('aria-expanded','true');a.style.maxHeight=a.scrollHeight+'px'}})})})();<\/script><\/p>","protected":false},"excerpt":{"rendered":"<p>\u2190 Abrasive Blasting for Medical Devices: Complete Guide SLA Surface  [&#8230;]<\/p>","protected":false},"author":1,"featured_media":13666,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[62,175,138],"tags":[],"class_list":["post-13664","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog","category-industry","category-resource"],"_links":{"self":[{"href":"https:\/\/hlh-js.com\/ja\/wp-json\/wp\/v2\/posts\/13664","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/hlh-js.com\/ja\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/hlh-js.com\/ja\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/hlh-js.com\/ja\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/hlh-js.com\/ja\/wp-json\/wp\/v2\/comments?post=13664"}],"version-history":[{"count":3,"href":"https:\/\/hlh-js.com\/ja\/wp-json\/wp\/v2\/posts\/13664\/revisions"}],"predecessor-version":[{"id":13688,"href":"https:\/\/hlh-js.com\/ja\/wp-json\/wp\/v2\/posts\/13664\/revisions\/13688"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/hlh-js.com\/ja\/wp-json\/wp\/v2\/media\/13666"}],"wp:attachment":[{"href":"https:\/\/hlh-js.com\/ja\/wp-json\/wp\/v2\/media?parent=13664"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/hlh-js.com\/ja\/wp-json\/wp\/v2\/categories?post=13664"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/hlh-js.com\/ja\/wp-json\/wp\/v2\/tags?post=13664"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}