๐ ็ธฝ็ฎ้ ๏ฝ ๐ ่ฑๆๅๆ๏ผๆฌ็ฏ๏ผ ๏ฝ ๐ ๅฎๆด็ฟป่ญฏ ๏ฝ โญ ็ฒพ่ฏ็ญ่จ
Polymethylmethacrylate
Polymethylmethacrylate
Bellafill, formerly marketed as Artefill in the United States, is a solution of PMMA beads in 3.5% bovine collagen and 0.3% lidocaine with sterile water, phosphate buffer, and sodium chloride. The 30- to 50-ยตm microspheres are nonabsorbable and inert, made of the same compound as acrylic glass (trade names PlexiglassTM, LuciteTM, and
PerspexTM) or in orthopedic bone cement and intraocular lens implants for cataract surgery. The collagen in Bellafill/Artefill acts as a fluid carrier that degrades over 1 to 3 months and leaves intact beads, which become encapsulated in endogenous collagen.27,34
In 2006, Bellafill/Artefill became the first and only FDA-approved permanent filler available for correction of the nasolabial folds.35 In 2015, it gained an indication for treatment of moderate to severe, distensible, atrophic acne scars in those over age 21 years. Skin testing for hypersensitivity reaction to the bovine collagen component is necessary before augmentation.
Unlike its predecessors, Arteplastยฎ and Artecollยฎ, Bellafill/Artefill has a lower rate of inflammatory adverse reactions, because the PMMA particles are more spherical, smooth, and uniformly sized. The manufacturer eliminated smaller microspheres measuring <20 ยตm, which are readily phagocytosed and cause granulomas.
A 5-year follow-up analysis of patients on the Bellafill/Artefill FDA pivotal nasolabial folds trial found that most were satisfied or very satisfied (95% and 83%, respectively) with their long-term results. Only 2% reported delayed adverse events, including irregular contour or granuloma formation, most of which were treatable.36 Seventy-seven percent of participants in the acne scarring phase 3 trial reported improvement at 6 months compared to 44% of controls; these results persisted up to 1 year of follow-up. There were no delayed granulomas noted in the latter study. The authors do not recommend injecting this product off-label in large quantities for volumizing, where there is a greater incidence of severe, recurrent subcutaneous inflammation and induration.37