I n the search for the perfect filling agent, dermatologists have tapped into a variety of substances throughout the decades in order to achieve natural-appearing, safe and long lasting soft tissue augmentation. Current FDA-approved bioabsorbable and permanent substances (either by cosmetic indication or by off-label use) include Zyderm, Zyplast, Fascian, Cymetra, Alloderm implants, fat transfer, silicone liquid and Gortex implants. FDA-prohibited substances that are widely used around the world and are currently under investigation in the United States include the hyaluronic acid gels such as Restylane and Hylaform, and New Fill, which is a polymer of polylactic acid. Of all these agents, silicone has had the longest history of clinical application and the greatest amount of controversy, which has brought its popularity as a filling agent in and out of vogue. Since 1994 when the FDA gave a pre-market approval indication for the first liquid injectable silicone product legally marketed in the United States, we’re once again seeing a resurgence of its use — and the controversy that surrounds it. The Science of Silicone Silicone is a generic name for a group of polymers, which are based on the element silicon and which range in viscosity from fluids to solids.1 Commercially available silicone oils contain polydimethylsiloxane polymers, composed of silicon, oxygen and methane molecules, which vary in length and therefore viscosities. Liquid injectable silicone, although not totally biologically inert, has been shown to have the least physiologic reactivity of most foreign materials.2 No true allergies to silicone have been documented, and the substance remains devoid of reproductive, mutagenic and carcinogenic effects. Currently, there are two FDA-approved, medical-grade liquid injectable silicone devices available that differ greatly in viscosity: Adatosil 5000 (Bausch & Lomb Surgical, Claremont, CA) and Silikon 1000 (Alcon Laboratories, Inc., Forth Worth, TX). Both agents are FDA approved for ophthalmologic use to tamponade retinal detachments and are used off-label for soft tissue augmentation. The FDA has also recently approved an investigational device exemption (IDE) to ascertain the safety and efficacy of a medical-grade silicone, Silskin (RJ Development Corp., Peabody, MA), for the treatment of facial rhytides. Dermatologists [Dr. Frank and Rhoda Narins, M.D.] are currently evaluating the safety and efficacy of the available forms of liquid silicone relative to traditional filling agents in treating facial wrinkles. The Microdroplet Technique In order to inject these silicone fillers, dermatologists must be trained in the microdroplet injection technique. In 2000, Orentreich reviewed the risks, benefits and method of this microdroplet serial puncture technique, which patients are given at monthly treatment intervals until the desired cosmetic result is achieved.3 Small aliquots of 0.005 ml to 0.01 ml of liquid silicone is inserted into the skin at 2-mm to 10-mm intervals and is suggested to provide a safe, permanent and consistent result for several cosmetic applications, including the filling of rhytides, scars and dystrophies of varied depths and anatomic locations. Results are incrementally perceivable over several months and are dependent on the severity of the condition being treated. The mechanism of action in achieving a safe and cosmetically excellent result is thought to be a combination of the displacement of the dermal connective tissue by silicone microdroplets and the production of thin-walled collagen capsules that surround them. When small amounts of silicone are placed at the appropriate depth in tissue over extended periods of time, the hallmark risks of the past that have been associated with liquid injectable silicone are thought to be dramatically minimized. Documented minor adverse reactions are similar to those associated with other traditional filling agents and include pain upon injection, local and transient edema, dyschromia and textural complaints. More concerning adverse reactions that appear to be more specific to liquid injectable silicone include granulomatous reactions, idiosyncratic inflammatory reaction, and reports of drifting.4 What’s most problematic about these reactions is that they’ve been reported to occur anywhere from 1 month to 25 years after initial treatment. In addition, because liquid injectable silicone is a permanent filler, any complication becomes compounded by the fact that the body won’t eventually metabolize the substance and the reaction can potentially persist despite treatment. Benefit/Risk Ratio It’s the varied perception of the weighted risks and benefits of silicone that has created such intense controversy, despite its continuous use for soft tissue augmentation for more than 40 years. This controversy was recently addressed separately by Duffy and Rappaport in Dermatologic Surgery.5,6 It appears that advocates of silicone attribute the majority of serious adverse reactions to improper technique, injection of large volumes and impurities in the liquid. Opponents of silicone focus on unpredictable and potentially untreatable complications that can occur despite proper technique. In addition, the lack of long-term clinical data regarding the incubation period of a serious adverse reaction deems liquid injectable silicone a time bomb to its opponents. Unfortunately, we have a lack of long-term clinical data and reporting regarding the number of patients who have been treated properly or improperly and how many patients have had appropriate results or serious complications. These facts often cloud the ability of clinicians to appropriately weigh the risks and benefits of liquid silicone for use in soft tissue augmentation. Both sides agree, however, that serious complications are possible, yet rare (a fraction of 1%), when pure liquid silicone is used in small volumes, over extended periods of time, and in appropriate anatomic locations. An Effective Option We believe that liquid injectable silicone is an excellent permanent filling agent when used with caution in an appropriate candidate [Dr. Frank has been regularly using silicone in his practice for the past 3 years]. No serious complications have yet occurred with the microdroplet technique. But as with any cosmetic procedure, complications can occur. So, it’s important to consider several options of treatment, permanent and temporary, with the expectations, constitution and ability of the patient to weigh the risks and benefits of a procedure. In the meantime, it’s currently legal to use the available forms of liquid silicone off-label for the purposes of soft tissue augmentation. It’s necessary for clinicians to properly treat patients and report their results so that the safety and efficacy of liquid injectable silicone can be appropriately assessed and the controversy elucidated over time.
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The Silicone Conundrum
I n the search for the perfect filling agent, dermatologists have tapped into a variety of substances throughout the decades in order to achieve natural-appearing, safe and long lasting soft tissue augmentation. Current FDA-approved bioabsorbable and permanent substances (either by cosmetic indication or by off-label use) include Zyderm, Zyplast, Fascian, Cymetra, Alloderm implants, fat transfer, silicone liquid and Gortex implants. FDA-prohibited substances that are widely used around the world and are currently under investigation in the United States include the hyaluronic acid gels such as Restylane and Hylaform, and New Fill, which is a polymer of polylactic acid. Of all these agents, silicone has had the longest history of clinical application and the greatest amount of controversy, which has brought its popularity as a filling agent in and out of vogue. Since 1994 when the FDA gave a pre-market approval indication for the first liquid injectable silicone product legally marketed in the United States, we’re once again seeing a resurgence of its use — and the controversy that surrounds it. The Science of Silicone Silicone is a generic name for a group of polymers, which are based on the element silicon and which range in viscosity from fluids to solids.1 Commercially available silicone oils contain polydimethylsiloxane polymers, composed of silicon, oxygen and methane molecules, which vary in length and therefore viscosities. Liquid injectable silicone, although not totally biologically inert, has been shown to have the least physiologic reactivity of most foreign materials.2 No true allergies to silicone have been documented, and the substance remains devoid of reproductive, mutagenic and carcinogenic effects. Currently, there are two FDA-approved, medical-grade liquid injectable silicone devices available that differ greatly in viscosity: Adatosil 5000 (Bausch & Lomb Surgical, Claremont, CA) and Silikon 1000 (Alcon Laboratories, Inc., Forth Worth, TX). Both agents are FDA approved for ophthalmologic use to tamponade retinal detachments and are used off-label for soft tissue augmentation. The FDA has also recently approved an investigational device exemption (IDE) to ascertain the safety and efficacy of a medical-grade silicone, Silskin (RJ Development Corp., Peabody, MA), for the treatment of facial rhytides. Dermatologists [Dr. Frank and Rhoda Narins, M.D.] are currently evaluating the safety and efficacy of the available forms of liquid silicone relative to traditional filling agents in treating facial wrinkles. The Microdroplet Technique In order to inject these silicone fillers, dermatologists must be trained in the microdroplet injection technique. In 2000, Orentreich reviewed the risks, benefits and method of this microdroplet serial puncture technique, which patients are given at monthly treatment intervals until the desired cosmetic result is achieved.3 Small aliquots of 0.005 ml to 0.01 ml of liquid silicone is inserted into the skin at 2-mm to 10-mm intervals and is suggested to provide a safe, permanent and consistent result for several cosmetic applications, including the filling of rhytides, scars and dystrophies of varied depths and anatomic locations. Results are incrementally perceivable over several months and are dependent on the severity of the condition being treated. The mechanism of action in achieving a safe and cosmetically excellent result is thought to be a combination of the displacement of the dermal connective tissue by silicone microdroplets and the production of thin-walled collagen capsules that surround them. When small amounts of silicone are placed at the appropriate depth in tissue over extended periods of time, the hallmark risks of the past that have been associated with liquid injectable silicone are thought to be dramatically minimized. Documented minor adverse reactions are similar to those associated with other traditional filling agents and include pain upon injection, local and transient edema, dyschromia and textural complaints. More concerning adverse reactions that appear to be more specific to liquid injectable silicone include granulomatous reactions, idiosyncratic inflammatory reaction, and reports of drifting.4 What’s most problematic about these reactions is that they’ve been reported to occur anywhere from 1 month to 25 years after initial treatment. In addition, because liquid injectable silicone is a permanent filler, any complication becomes compounded by the fact that the body won’t eventually metabolize the substance and the reaction can potentially persist despite treatment. Benefit/Risk Ratio It’s the varied perception of the weighted risks and benefits of silicone that has created such intense controversy, despite its continuous use for soft tissue augmentation for more than 40 years. This controversy was recently addressed separately by Duffy and Rappaport in Dermatologic Surgery.5,6 It appears that advocates of silicone attribute the majority of serious adverse reactions to improper technique, injection of large volumes and impurities in the liquid. Opponents of silicone focus on unpredictable and potentially untreatable complications that can occur despite proper technique. In addition, the lack of long-term clinical data regarding the incubation period of a serious adverse reaction deems liquid injectable silicone a time bomb to its opponents. Unfortunately, we have a lack of long-term clinical data and reporting regarding the number of patients who have been treated properly or improperly and how many patients have had appropriate results or serious complications. These facts often cloud the ability of clinicians to appropriately weigh the risks and benefits of liquid silicone for use in soft tissue augmentation. Both sides agree, however, that serious complications are possible, yet rare (a fraction of 1%), when pure liquid silicone is used in small volumes, over extended periods of time, and in appropriate anatomic locations. An Effective Option We believe that liquid injectable silicone is an excellent permanent filling agent when used with caution in an appropriate candidate [Dr. Frank has been regularly using silicone in his practice for the past 3 years]. No serious complications have yet occurred with the microdroplet technique. But as with any cosmetic procedure, complications can occur. So, it’s important to consider several options of treatment, permanent and temporary, with the expectations, constitution and ability of the patient to weigh the risks and benefits of a procedure. In the meantime, it’s currently legal to use the available forms of liquid silicone off-label for the purposes of soft tissue augmentation. It’s necessary for clinicians to properly treat patients and report their results so that the safety and efficacy of liquid injectable silicone can be appropriately assessed and the controversy elucidated over time.
I n the search for the perfect filling agent, dermatologists have tapped into a variety of substances throughout the decades in order to achieve natural-appearing, safe and long lasting soft tissue augmentation. Current FDA-approved bioabsorbable and permanent substances (either by cosmetic indication or by off-label use) include Zyderm, Zyplast, Fascian, Cymetra, Alloderm implants, fat transfer, silicone liquid and Gortex implants. FDA-prohibited substances that are widely used around the world and are currently under investigation in the United States include the hyaluronic acid gels such as Restylane and Hylaform, and New Fill, which is a polymer of polylactic acid. Of all these agents, silicone has had the longest history of clinical application and the greatest amount of controversy, which has brought its popularity as a filling agent in and out of vogue. Since 1994 when the FDA gave a pre-market approval indication for the first liquid injectable silicone product legally marketed in the United States, we’re once again seeing a resurgence of its use — and the controversy that surrounds it. The Science of Silicone Silicone is a generic name for a group of polymers, which are based on the element silicon and which range in viscosity from fluids to solids.1 Commercially available silicone oils contain polydimethylsiloxane polymers, composed of silicon, oxygen and methane molecules, which vary in length and therefore viscosities. Liquid injectable silicone, although not totally biologically inert, has been shown to have the least physiologic reactivity of most foreign materials.2 No true allergies to silicone have been documented, and the substance remains devoid of reproductive, mutagenic and carcinogenic effects. Currently, there are two FDA-approved, medical-grade liquid injectable silicone devices available that differ greatly in viscosity: Adatosil 5000 (Bausch & Lomb Surgical, Claremont, CA) and Silikon 1000 (Alcon Laboratories, Inc., Forth Worth, TX). Both agents are FDA approved for ophthalmologic use to tamponade retinal detachments and are used off-label for soft tissue augmentation. The FDA has also recently approved an investigational device exemption (IDE) to ascertain the safety and efficacy of a medical-grade silicone, Silskin (RJ Development Corp., Peabody, MA), for the treatment of facial rhytides. Dermatologists [Dr. Frank and Rhoda Narins, M.D.] are currently evaluating the safety and efficacy of the available forms of liquid silicone relative to traditional filling agents in treating facial wrinkles. The Microdroplet Technique In order to inject these silicone fillers, dermatologists must be trained in the microdroplet injection technique. In 2000, Orentreich reviewed the risks, benefits and method of this microdroplet serial puncture technique, which patients are given at monthly treatment intervals until the desired cosmetic result is achieved.3 Small aliquots of 0.005 ml to 0.01 ml of liquid silicone is inserted into the skin at 2-mm to 10-mm intervals and is suggested to provide a safe, permanent and consistent result for several cosmetic applications, including the filling of rhytides, scars and dystrophies of varied depths and anatomic locations. Results are incrementally perceivable over several months and are dependent on the severity of the condition being treated. The mechanism of action in achieving a safe and cosmetically excellent result is thought to be a combination of the displacement of the dermal connective tissue by silicone microdroplets and the production of thin-walled collagen capsules that surround them. When small amounts of silicone are placed at the appropriate depth in tissue over extended periods of time, the hallmark risks of the past that have been associated with liquid injectable silicone are thought to be dramatically minimized. Documented minor adverse reactions are similar to those associated with other traditional filling agents and include pain upon injection, local and transient edema, dyschromia and textural complaints. More concerning adverse reactions that appear to be more specific to liquid injectable silicone include granulomatous reactions, idiosyncratic inflammatory reaction, and reports of drifting.4 What’s most problematic about these reactions is that they’ve been reported to occur anywhere from 1 month to 25 years after initial treatment. In addition, because liquid injectable silicone is a permanent filler, any complication becomes compounded by the fact that the body won’t eventually metabolize the substance and the reaction can potentially persist despite treatment. Benefit/Risk Ratio It’s the varied perception of the weighted risks and benefits of silicone that has created such intense controversy, despite its continuous use for soft tissue augmentation for more than 40 years. This controversy was recently addressed separately by Duffy and Rappaport in Dermatologic Surgery.5,6 It appears that advocates of silicone attribute the majority of serious adverse reactions to improper technique, injection of large volumes and impurities in the liquid. Opponents of silicone focus on unpredictable and potentially untreatable complications that can occur despite proper technique. In addition, the lack of long-term clinical data regarding the incubation period of a serious adverse reaction deems liquid injectable silicone a time bomb to its opponents. Unfortunately, we have a lack of long-term clinical data and reporting regarding the number of patients who have been treated properly or improperly and how many patients have had appropriate results or serious complications. These facts often cloud the ability of clinicians to appropriately weigh the risks and benefits of liquid silicone for use in soft tissue augmentation. Both sides agree, however, that serious complications are possible, yet rare (a fraction of 1%), when pure liquid silicone is used in small volumes, over extended periods of time, and in appropriate anatomic locations. An Effective Option We believe that liquid injectable silicone is an excellent permanent filling agent when used with caution in an appropriate candidate [Dr. Frank has been regularly using silicone in his practice for the past 3 years]. No serious complications have yet occurred with the microdroplet technique. But as with any cosmetic procedure, complications can occur. So, it’s important to consider several options of treatment, permanent and temporary, with the expectations, constitution and ability of the patient to weigh the risks and benefits of a procedure. In the meantime, it’s currently legal to use the available forms of liquid silicone off-label for the purposes of soft tissue augmentation. It’s necessary for clinicians to properly treat patients and report their results so that the safety and efficacy of liquid injectable silicone can be appropriately assessed and the controversy elucidated over time.
