Ariga Nazarian,1,*Atefeh Solouk Mofrad,2Masoud Hafezi Ardakani,3Masoumeh Haghbin Nazarpak,4Ali Rastgoftar,5
1. Biomedical Engineering Department, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran. 2. Biomedical Engineering Department, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran. 3. Biomedical Engineering Department, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran. 4. New Technologies Research Center (NTRC), Amirkabir University of Technology, Tehran, Iran. 5. Biomedical Engineering Department, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran.
Introduction: Due to the importance of grace throughout history many techniques have been designed in order to rejuvenate and treat dermal defects. The use of soft tissue fillers has become an essential tool in aesthetic rejuvenation.
The ideal dermal filler should be safe, inexpensive, hypoallergenic, easy to store, painless to inject, require no allergy testing and have no risk of complications.
Skin fillers today are categorized into biodegradable or resorbable, and permanent or non-resorbable fillers. Resorbable fillers divided into two categories: (1) nonpermanent fillers also known as replacement fillers such as fillers based on collagen, hyaluronic acid, which have short durability and are resorbed through macrophage activation: (2) semipermanent fillers or stimulatory fillers such as polylactic acid (PLLA) and calcium hydroxyapatite (CaHA) based dermal fillers, which have longer lasting results, they cause foreign body reactions that motivate fibroblast activation and collagenesis at the site of injection. Permanent fillers/implants like polymethylmethacrylate (PMMA) and silicone could provide long lasting results, but with high risk of complications.
In this article we discuss the most common types of fillers, their characteristics and complications.
Methods: In this study, we have been used the method of library collection, search in various texts and authoritative scientific articles and 54 articles about dermal fillers and their characteristics from PubMed and Google Scholar have been reviewed.
Results: Facial tissue aging and volume loss have been treated for more than a century, as fat grafting reported as early as 1893. In the early 1900’s liquid paraffin had been utilized for facial rejuvenation but regarding the high rate of complications stopped soon. In the 1970’s and 1980’s, silicone gel had been utilized, that consists of solid silicone particles suspended in a polyvinyl pyrrolidone carrier. According to many complications like chronic inflammation and granuloma formation had been transferred by means of PMMA suspended in a bovine collagen.
Owing to non-biodegradability of PMMA, this filler is permanent, therefore utilization of this kind of filler had not been noticed very well. A skin test is necessary before treatment to determine possible sensitivity to bovine collagen as it may cause hypersensitivity reactions. The main concern about the use of permanent filler, is the possibility of late-onset adverse events or displacement of the material when facial structures change with the aging process.
The first filler which was approved by FDA to correct the signs of facial fat loss, was poly-L-lactic acid (PLLA) in 2004. PLLA is considered to be a deep tissue regenerator, providing soft tissue augmentation through stimulation of fibroblast production.
Injectable gels based on Hyaluronic acid (HA) are the other non-permanent type of dermal fillers which does not need allergy testing and has better durability toward early fillers. Many factors are effective on ultimate properties and injectability of gel, hence the accessibility of ideal fillers based on HA won't be convenient so much.
Due to many complications caused by early fillers, these days composite fillers, like fillers based on Calcium hydroxyapatite has been noticed due to traits like non pyrogenic, biocompatibility, biodegradability, non-migratory, and appropriate durability (12 to 18 months). Although these fillers don't cause antigenic effects and have capability of sterilization.
The best aesthetic results are achieved when selecting the appropriate filler. The appropriate filler should be selected based on site of injection, patient-specific goals and tissue properties.
Conclusion: In this study, we tried to give a brief and useful study of dermal fillers material and properties.
As we noticed in article, there are number of dermal fillers which are used for treatment but composite dermal fillers are novel rejuvenate candidates, and have potential to treating facial aging symptoms with least number of side effects as compared to other dermal fillers. Incorporation of primary gels with other materials like hydroxyapatite achieve the desired results for ideal filler, such as safety, non-immunogenicity, minimizing any risk of an allergic reactions, non-migratory and etc.
Continued innovations in facial fillers are aimed at developing longer-lasting and more natural products with fewer adverse effects and improved patient-reported outcomes.