Atrophic Acne Scars Research Articles

A Comprehensive Review of Non-Energy-Based Treatments for Atrophic Acne Scarring.

Scarring is a dire consequence of acne vulgaris. Particularly, atrophic acne scarring is highly prevalent among young adults, and its physical and psychological effects can persist throughout their lives if left untreated. This literature review will analyze various non-energy-based approaches to treating atrophic acne scarring, emphasizing recent advances within the last 5 to 10 years. To accomplish this, we performed a PubMed search for various acne scar treatments such as chemical peels, dermabrasion, microdermabrasion, subcision, microneedling, punch techniques, dermal fillers, and thread lifting. Our findings and analysis show that there is no panacean solution to treating atrophic acne scars, which explains the evolving trend towards developing unique combinatorial treatments. Although a fair comparison of each treatment approach is difficult to achieve due to the studies’ varying sample sizes, strength of evidence, treatment execution, etc, there still remains a level of consensus on what treatments are well suited for particular scar types.

Efficacy and safety of topical timolol 0.5% plus saline 0.9% versus each one alone in acne scar trichloroacetic acid-CROSS therapy: A blinded randomized controlled trial.

Trichloroacetic acid-CROSS (TCA-CROSS) or chemical reconstruction of scars is an approved method in the treatment of ICE-PICK scars. Timolol is a blocker of beta-adrenergic receptors that speeds up the healing of skin wounds. In this study, for the first time, the TCA-CROSS technique was combined with the use of saline injection and topical timolol to increase the effectiveness of treatment, and reduce the number of treatment sessions and complications, and thus improve the aesthetic result. In this parallel-group split-face randomized controlled assessor and analyst-blinded study, 45 patients with atrophic acne scars were randomly divided into 3 equal groups. TCA-CROSS treatment was performed on all facial scars of patients. In group 1, before TCA-CROSS, saline was injected under the scars on one side of the face, in group 2, after TCA-CROSS, 0.5% timolol eye drops were applied on the scars on one side, and in group 3, saline was injected before TCA-CROSS. After that, timolol eye drops were applied on the scars of the same side. In all groups, the choice of control side was random. The number of scars and patient and physician satisfaction were the main variables evaluating the effectiveness of the treatment. TCA-CROSS improved scars in both control and treatment sides of all 3 groups. Although the number of scars decreased on the treatment side of groups 2 and 3, the decrease was not statistically significant. In the saline + TCA group, the number of scars on the treatment side was slightly more than on the control side. In the group of patients who used timolol, the severity and duration of scar hyperpigmentation were significantly lower (group 2 p= 0.016, group 3 p= 0.002). No permanent complication was observed in the patients. Patients' satisfaction in groups 2 and 3 was higher in the treatment side than the control side. The combination of saline injection followed by TCA-CROSS is not recommended. Application of 0.5% timolol after TCA-CROSS caused a slight decrease in scar severity and a significant reduction of post-inflammatory hyperpigmentation (PIH) duration. So, the topical timolol makes a better result of TCA-CROSS for acne scar treatment.

Treatment of acne scars with fractional carbon dioxide laser in Asians: a retrospective study to search for predicting factors associated with efficacy.

Ablative fractional laser treatment has been extensively used for resurfacing atrophic acne scars. However, few studies have investigated how the parameters set during laser procedures affect efficacy. In this retrospective study, we examined the relationship between efficacy and Fitzpatrick skin type, gender, age, follow-up duration, energy, and treatment sessions utilizing ablative fractional carbon dioxide (CO2) laser in Asians with Fitzpatrick skin types III-IV. We then analyzed the relationship between outcome and adverse effects including hyperpigmentation. Three blinded dermatologists used the ECCA (Echelle d'Evaluation Clinique des Cicatrices d'Acnluation Clinique des Cicospectively review 82 of 1034 patients who presented at our institution for atrophic acne scar treatment between August 2013 and August 2019. Factors associated with efficacy, including age, gender, Fitzpatrick skin type, energy, treatment sessions, follow-up duration, and pigmentation, were analyzed. 82 patients met inclusion criteria. Patients underwent one to three CO2 laser treatment sessions. Parameter settings for individual patients were consistent across treatments. Mean ECCA scores decreased from 102.70 ± 24.95 to 87.28 ± 24.48 (p ≤ 0.001). The number of treatment sessions and duration of pigmentation lasting shorter than 3months positively correlated with better outcomes. All patients had erythema, which lasted longer than 3months in 16 patients (19.51%). Post-inflammatory hyperpigmentation (PIH) affected 60 patients (73.17%) and lasted longer than 3months in 26 patients (31.71%). One patient experienced hypopigmentation (1.22%), while 8 experienced acne flare-up (9.76%). Post-laser scars occurred in 2 patients (2.44%). Our data suggest that in atrophic acne scar treatment in Asians using fractional CO2 laser, 3 treatment sessions and duration of hyperpigmentation within 3months have better outcomes regardless of energy, gender, age, Fitzpatrick skin type, follow-up duration, and disease course.

Efficacy and adverse reactions of fractional CO2 laser for atrophic acne scars and related clinical factors: A retrospective study on 121 patients.

This study was performed to analyze the efficacy, adverse reactions of fractional CO2 laser for atrophic acne scars, and related clinical factors. The clinical data of 121 patients with atrophic acne scars treated with ultra-pulsed fractional CO2 laser in the Cosmetic Dermatology from August 2014 to March 2020 were retrospectively analyzed. The efficacy and adverse reactions of atrophic acne scar after fractional CO2 laser therapy were statistically analyzed. The clinical factors related to efficacy and adverse reactions after the first therapy session were analyzed by multivariate logistic regression. A total of 121 patients received 206sessions of fractional CO2 laser therapy, with an average of 1.7sessions. Moderate to excellent improvement rate reached 50.4% after the first session. Multivariate logistic regression analysis indicated that rolling scars responded better to fractional CO2 laser treatment than icepick scars (OR=7.3, 95% CI [1.2, 43.4], p=0.029), and scar improvement was more significant in the high-energy laser group than in the low-energy laser group (OR=10.9, 95% CI [1.1, 106.8], p=0.041). The main adverse reactions after fractional laser surgery were pigmentation, skin sensitivity, persistent erythema, and acneiform eruption. Multivariate logistic analysis revealed that the longer the scar duration, the higher incidence of postoperative adverse reactions (OR=1.3, 95% CI [1.1, 1.5], p=0.008). Compared with icepick scars, rolling scars (OR=10.4, 95% CI [2.3, 47.7], p=0.003) and boxcar scars (OR=12.0, 95% CI [3.3, 44.0], p<0.001) had higher risk of developing adverse reactions. The incidence of postoperative adverse reactions was also higher in the combined mode group (DeepFX mode+ActiveFX mode) than in the single-mode group (OR=7.8, 95% CI [2.4, 25.5], p<0.001). Fractional CO2 laser was effective in the treatment of atrophic acne scars, without serious adverse reactions. Scar type and laser energy were independent clinical factors affecting its efficacy. Scar course, scar type, and fractional laser mode were independent clinical factors affecting its adverse reactions.

Fractional carbon dioxide LASER for acne scars

Acne is a common disease and patients frequently suffer from its distressing sequela of scarring which affects their quality of life. The treatment strategy for acne scars is usually influenced by multiple factors and we need to choose the best fit from amongst the various therapeutic modalities available. Lasers are increasingly being used and fractional ablative lasers create microthermal zones leading to collagen regeneration and reorganization in the target area. Fractional carbon dioxide laser has shown clinical efficacy in skin renewal in atrophic acne scars. Patient selection, counseling, pre, and postprocedure care guidelines form essential factors influencing the procedure outcomes. Here we discuss practical aspects of the use of fractional carbon dioxide laser in acne scar management along with pointers on patient selection, pre and postprocedure care, and side effects.

A Meta-Analysis of the Evidence for Assisted Therapy with Platelet-Rich Plasma for Atrophic Acne Scars.

A Meta-Analysis of the Evidence for Assisted Therapy with Platelet-Rich Plasma for Atrophic Acne Scars.

Single session of combined microfat and subcision in the treatment of Grade 4 atrophic acne scars.

Severe atrophic acne scars (AAS) remain the "Achilles's heel" of AAS treatment. The combination of microfat and subcision treatment is a potential solution for severe AAS. This study aimed to evaluate the efficacy and safety of combined microfat and subcision treatment for severe (Grade 4) AAS. Data of patients with Grade 4 AAS who underwent combined microfat and subcision treatment between September 2016 and December 2020 were reviewed. Post-treatment evaluation was performed at least 3months postoperatively. The severity of AAS was graded based on Goodman's qualitative classification. The volume of concavities was measured using an Antera 3D camera. Complications were documented. A total of 42 patients received a single treatment session. Excellent response was observed in 5 (11.9%) patients, very good in 13 (31.0%), good in 22 (52.4%), and poor response in 2 (4.7%). The average reduction of the total volume of concavities was 28.0%. The most common minor side effects were mild swelling and bruising. No major complications were observed. Combined microfat and subcision treatment is a safe and effective treatment for severe AAS. The approach will be a significant treatment for severe AAS.

Evaluation of the cumulative effect of Radiofrequency Microneedling and fractional Erbium: Glass 1565 laser in moderate to severe acne scars in skin of color.

Evaluation of the cumulative effect of Radiofrequency Microneedling and fractional Erbium: Glass 1565 laser in moderate to severe acne scars in skin of color. This retrospective study was conducted on 20 patients of skin types III -V having moderate to severe atrophic acne scars. The study was carried out over 1year from March 2019 to March 2020. All patients underwent 4 sessions of non-ablative Fractional Erbium: Glass 1565 laser to alternate with 4 sessions of Fractional Radiofrequency Microneedling once a month over 8months. Of the 20 patients enrolled, 18 completed treatment protocol. Two patients were withdrawn from the study because they were unable to attend follow-up treatment sessions. The subjective evaluation was performed using photographs at baseline, 8months, and 12months. A photographic evaluation was performed using the following numeric responses: <25%, 25-50%, 51-75%, and 76-100% difference in severity. None of the patients had worsening of their scars. The improvement in scars was statistically significant. The combination of Fractional Erbium: Glass 1565 laser and Fractional Radiofrequency Microneedling can be used in the treatment of acne scars in skin of color. Our protocols helped achieve significant improvement of scars.

Microneedling Radiofrequency for Acne Vulgaris and Post-Acne Scarring: A Case Report

Background: There are various therapeutic modalities for acne and post acne scarring, but the best option is to have a safe, effective with affordable cost such as monotherapy or combination therapy. One of the recommended combination therapy for acne vulgaris with atrophic acne scars is microneedling radiofrequency which can improve skin structure.&#x0D; Case report: A 25 year old male with moderate comedonal acne vulgaris and severe scarring. The patient came with complaints of uneven skin surface on both cheeks, forehead and chin which had been felt to increase since 3 years ago. The appearance of acne on the face has been felt since 12 years ago. The patient's parents and sister also had acne complaints. On dermatological examination, on the forehead, temples, cheeks, nose and chin found blackheads, whiteheads, papules, hyperpigmented macules, multiple atrophic acne scars. The treatment choice for this patient is microneedling radiofrequency in combination with topical therapy.&#x0D; Discussion: The combination of microneedling with radiofrequency is one of the therapeutic modalities for acne vulgaris and also post-acne scarring with minimal side effects. In the evaluation for 2 weeks after the procedure, this patient did not complaint of any adverse events.

Treatment protocols and efficacy of light and laser treatments in post-acne erythema.

Post-acne erythema is described as erythema due to release of inflammatory cytokines, dilatation of microcapillaries within papillary dermis and thinning of epidermis. The erythema usually fades; however, it can persist for months. In this review, we decided to evaluate efficacy of light and laser treatments in acne-induced erythema. We searched PUBMED, Embase, Cochrane, and Google Scholar for relevant key words. Inclusion criteria were randomized clinical trials (RCTs) that evaluated efficacy of laser or light in PAE until September 2021. Twelve RCTs were selected for the final assessment. Light and laser treatments included pulsed dye laser (PDL), intense pulsed light (IPL), Q-switched neodymium-doped yttrium aluminum garnet (QS Nd:YAG), fractional photothermolysis, alexandrite, solid-slate 589-1319nm, and pro-yellow laser. Light and laser treatments are effective treatment modalities in reduction of acne-induced erythema along with active acne lesions and atrophic acne scars.

Monotherapy of Biofiller for Atrophic Acne Scars: A Prospective Nonrandomized Study.

Atrophic acne scarring is an unpleasant and often permanent complication and a therapeutic challenge for dermatologists. Platelet-poor plasma (PPP) gel injections are derived from the patient's own blood and used as a "biofiller" for skin rejuvenation. The objective was to study the efficacy and safety profile of PPP gel in atrophic acne scars. Thirty patients with atrophic acne scars were included in the study. Topical anesthesia was applied on the area of interest 45 min prior to the procedure. 20 mL of blood was collected in eight sodium citrate bulbs and centrifuged to get PPP that is coagulated with heat to form gel. This gel (biofiller) was injected in the scarred areas monthly for 6 months. Patients were evaluated using Goodman and Baron Scar (GBS) scale (quantitative and qualitative), Physician Global Assessment, and Visual Analogue Scale (VAS) at each visit. The final visit was after 3 months of the last procedure. The mean value of GBS at the first visit was 28, which reduced to 8.2 at the final visit. The analysis of variance test was applied to the quantitative scale from the baseline visit to the final visit. The F value was 462.55 with a P value < 0.0001. The paired t-test was applied for the GBS quantitative scale, which showed a value of 22.86 with a P value of <0.001. Transient local side effects were noted. Biofiller is efficacious in improving atrophic acne scars. It is a simple, minimally invasive, cost-effective procedure with no risk of immunogenic reaction.

A Split Face Study to Compare the Efficacy of Platelet Rich Plasma Versus Normal Saline Injections in Acne Scars and to Assess the Utility of Ultrabiomicroscopic Sonography in Evaluation of Treatment Response.

Multiple studies have proposed the effectiveness of Platelet rich plasma (PRP) in treatment of atrophic acne scars. But an unanswered question is - whether it is the presence of growth factors in PRP or the mechanical factors during the injection that are responsible for its effectiveness? Also, no study compares PRP as a monotherapy against inert solution like normal saline (NS), that too, in a split face pattern using a non-invasive objective evaluation method. Primary - To compare the efficacy of intralesional PRP and NS injections, in the treatment of atrophic acne scars. Secondary - To assess the side effect profile of the PRP injections. Prospective Interventional Comparative Split Face study. 30 out of 33 patients completed the study and 20 of them were subjected to Ultrabiomicroscopic (UBM) analysis. Each patient received intralesional injections of NS and PRP in a split face pattern at two weekly intervals for five sittings. Treatment response was assessed using Goodman And Baron qualitative grading system, photographic evaluation by two blinded dermatologist and UBM analysis (scar depth & length). All the three methods showed a statistically significant treatment response. However, there was no significant inter group difference and PRP and NS had similar efficacy in treating acne scars. We conclude that subscision like mechanical effect of injecting solution is more important than the nature of the solution in treatment of atrophic acne scars and UBM sonography can be proposed as an objective assessment tool for such studies.

Topical enzymatic therapy of atrophic acne scars

<h3>АКТУАЛЬНОСТЬ</h3> Акне — социально значимое дерматовенерологическое заболевание с высокой распространенностью среди детского и взрослого населения. В результате разрешения воспалительных элементов формируется симптомокомплекс постакне, в ряде случаев завершающийся неблагоприятным исходом с формированием рубцовых деформаций. <h3>ЦЕЛЬ ИССЛЕДОВАНИЯ</h3> Изучение эффективности и безопасности применения ферментного геля в терапии атрофических рубцов постакне. <h3>МАТЕРИАЛ И МЕТОДЫ</h3> Клиническое продольное неконтролируемое исследование (before-after study), включившее 22 пациента с акне в анамнезе и поствоспалительными симптомами постакне. Пациенты наружно использовали гель с аквакомплексом глицеросольвата титана, коллагеназой и папаином 2 раза в день на участки кожи лица с атрофическими рубцами на протяжении 3 мес с ежемесячными контрольными осмотрами. Оценку эффективности терапии проводили после 3 мес применения препарата (с помощью оценочных шкал G.J. Goodman и Manchester Scar Scale). Влияние симптомокомплекса постакне на качество жизни пациентов изучали с помощью использования дерматологического индекса качества жизни (DLQI). <h3>РЕЗУЛЬТАТЫ</h3> В ходе исследования применения ферментного препарата обнаружены статистически значимые различия при оценке степени выраженности рубцов (G.J. Goodman, <i>p</i>&lt;0,05) и оценке клинико-функциональных параметров (Manchester Scar Scale, <i>p</i>&lt;0,05). После окончания терапии в результате опроса пациентов установлено улучшение качества жизни пациентов (DLQI, <i>p</i>&lt;0,001). <h3>ЗАКЛЮЧЕНИЕ</h3> В терапии атрофических рубцов постакне ферментный гель показал выраженную эффективность и безопасность применения.

Evaluation of psychological well-being and social impact of atrophic acne scarring: A multinational, mixed-methods study

BackgroundMost people with acne are at risk of developing acne scars, but the impact of these scars on patients' quality of life is poorly researched.ObjectiveTo assess the perspective of patients with acne scars and the impact of these scars on their emotional well-being and social functioning.MethodsA 60-minute interview of 30 adults with acne scars informed and contextualized the development of a cross-sectional survey of 723 adults with atrophic acne scars.ResultsThe main themes identified in the qualitative interviews included acceptability to self and others, social functioning, and emotional well-being. In the cross-sectional survey, 31.6%, 49.6%, and 18.8% of the participants had mild, moderate, and severe/very severe acne scarring. The survey revealed that 25.7% of the participants felt less attractive, 27.5% were embarrassed or self-conscious because of their scars, 8.3% reported being verbally and/or physically abused because of their scars on a regular basis, and 15.9% felt that they were unfairly dismissed from work. In addition, 37.5% of the participants believed that their scars affected people's perceptions about them, and 19.7% of the participants were very bothered about hiding their scars daily. Moreover, 35.5% of the participants avoided public appearances, and 43.2% felt that their scars had negatively impacted their relationships.LimitationsThe temporal evaluation of the impact was not estimated.ConclusionEven mild atrophic acne scarring can evoke substantial emotional, social, and functional concerns.

A combined approach of subcision with either cross-linked hyaluronic acid or threads in the treatment of atrophic acne scars.

Acne scars are one of the most common cosmetic concerns causing psychosocial distress. To evaluate the efficacy of subcision versus its combination with either cross-linked hyaluronic acid (HA) or poly-l-lactic acid (PLLA) threads in the treatment of atrophic post-acne scars. Forty patients of both genders with atrophic acne scars were subjected to subcision 1month apart for 3sessions. After the last session of subcision, the patients were reclassified randomly into 2equal groups each received either HA or threads in one side of the face leaving the other side that underwent subcision before as a control. Clinical assessment was carried out by the physicians and patients. Photographs and skin biopsies were obtained. Follow-up was 6months. A significant clinical improvement was achieved in 67.3% of patients after subcision alone compared to 94.1%, 82.4% of subcision combined with HA or threads, respectively. Patients' satisfaction was higher in the combined groups compared to subcision alone (p<0.0001). Side effects were tolerable and transient. Subcision combined with HA or threads could offer a higher significant clinical improvement of acne scars than subcision alone.

Efficacy and safety comparison between 1927\xa0nm thulium laser and 2940\xa0nm Er:YAG laser in the treatment of facial atrophic acne scarring: a prospective, simultaneous spilt-face clinical trial

Acne scarring is a common disfiguring complication of acne, and fractional lasers are widely applied in improving it. This study is to compare the efficacy and safety of fractional non-ablative 1927 nm thulium laser (FTL) and fractional ablative 2940 nm Er:YAG laser (FEL) in the treatment of acne scarring. Subjects with moderate or severe atrophic facial acne scarring received 3 sessions of FTL on the left side of face and FEL on the right side of face at an average interval of 4–6 weeks. Major assessments included Goodman&Baron quantitative global scarring grading system (GBS), self-rated improvement and satisfaction score. Twenty-seven subjects completed the study; for FTL side, average GBS decreased from 11.15 ± 5.04 at baseline to 7.07 ± 4.87 with an improvement percent of 36.54%; for FEL side, average GBS decreased from 10.81 ± 4.46 to 7.00 ± 4.07 with an improvement percent of 35.27%. Adverse effects include transient pain, erythema, edema, and increase of acne. No significant difference was found between two lasers. Both FTL and FEL improved atrophic acne scarring and were well-tolerated. Increase of acne during laser treatment may have a negative impact on efficacy. Trial registration number was NCT04813419 and date of registration was 19th, March, 2021, retrospectively registered.

Clinical and Histopathological evaluation of different tools for the Subcision of Atrophic Acne Scars

Acne scarring can lead to social and psychological distress. To compare the safety, efficacy, and long-term improvement of subcision using tri-beveled hypodermic (Th) needle versus cannula for the treatment of atrophic post-acne scars. Forty-six patients with atrophic post-acne scars were treated with subcision using (Th) needle on one side of the face and a blunt cannula on the other side of the face for 6sessions one month apart. The primary outcome was based on the clinical improvement and patient satisfaction score. Skin biopsies were taken at baseline and 3months after the final session. Follow-up was 9months. Three months after the final session, a statistically highly significant difference was detected in both sides from the baseline (p<0.001). The overall improvement was 73.9% on the (Th) needle side versus 65.2% on the cannula side (p=0.68). There was no significant difference in acne severity scarring grade between both sides (p=0.86). The mean number of sessions was significantly less in the (Th) needle side (p<0.001). Collagen deposition and reorganization were achieved with both modalities. Patient satisfaction showed no significant difference between both sides. The side effects were mild and significantly higher in the (Th) needle side (p=0.001). Both modalities are effective and economic techniques. However, using a cannula is associated with much fewer side effects, more convenient for the patients and physicians compared to the (Th) needle.

Updated treatment of Atrophic Acne Scars

Updated treatment of Atrophic Acne Scars

Impact of Facial Atrophic Acne Scars on Quality of Life: A Multi-country Population-Based Survey.

BackgroundAcne affects more than 80% of adolescents and young adults, who most often develop acne scars. Supporting data on the effect of acne scars on patient’s health-related quality of life (HRQOL) are limited.ObjectiveThe aim was to determine how the severity of acne scars impacts the HRQOL of afflicted individuals.MethodsIn this population-based cross-sectional study, 723 adults with facial acne scars but without active acne lesions self-completed the Self-assessment of Clinical Acne-Related Scars (SCARS) questionnaire formulated to investigate degree of acne scarring. The Facial Acne Scar Quality of Life (FASQoL), Dermatology Life Quality Index (DLQI), and Dysmorphic Concern Questionnaire (DCQ) were completed to assess the attitude of these patients toward their scars and the impact of scarring on their HRQOL.ResultsThe mean (standard error) DLQI score for facial acne scars was 6.26 (0.22). Acne scars were considered a ‘very large’ or ‘extremely large’ concern by 19.3% of participants with mild scars as compared to 20.1% and 34.0% of participants with moderate and severe/very severe scars, respectively (P = 0.003). Higher FASQoL scores were associated with increased severity of scarring (P = 0.001). In total, 16.9% of participants had clinical features of dysmorphia (i.e., DCQ > 13). DCQ scores were significantly higher among participants with more severe scarring (mean DCQ score of 8.04 [0.28], 8.40 [0.18], and 10.13 [0.08] among participants with mild, moderate, and severe/very severe acne scars, respectively; P = 0.001). Most commonly reported signs of emotional distress were self-consciousness (68.0%) and worry about scars not going away (74.8%).ConclusionsThis study highlights the significant psychosocial impact of atrophic acne scars in the form of embarrassment and self-consciousness. Individuals with mild scars also expressed significant impact on quality of life that increased with aggravation of scar severity. Patient-reported outcomes provide an insight into the physical, functional, and psychological impact of acne scarring from the patient’s perspective.Supplementary InformationThe online version contains supplementary material available at 10.1007/s40257-021-00628-1.

Updated Management of Atrophic Post Acne Scars: Review Article

Background: Hair follicle and sebaceous gland inflammation causes acne, which is a long-term, chronic skin condition. The androgen-induced sebum overproduction leads to first acne appearance. It is caused by altered and aberrant keratinization, inflammation and the colonization of facial hair follicles by the bacteria Propionibacterium acnes. Acne also has a delayed immune response, as well as influences from the environment and genetics. Treatments for post-acne scarring have included topical preparations such as chemical peels, dermabrasion, laser resurfacing and punch excision and punch elevation, as well as fat transfer, implantation of autologous collagen and cultured and expanded autologous fibroblasts. Other treatments have included trichloroacetic acid focal treatment and skin microneedling to improve the dermal extracellular matrix (ECM) proteins. Objective: To determine the updated treatment modalities in atrophic post-acne scars. Conclusion: In most types of atrophic acne scars combination therapies typically provide superior outcomes than solo treatments.