There was a statistically significant difference in SBS among the study groups (p<0.001). The highest SBS values were observed in the groups treated with the fractional CO2 laser at settings of 20 W/10 mJ (28.1 MPa) or 10 W/14 mJ (27.4 MPa), followed by the specimens treated with the universal primer (22.8 MPa). The control specimens exhibited the lowest SBS (9.4 MPa) among the study groups (p<0.05). There was no significant difference in the distribution of failure modes among the groups (p=0.871). The application of fractional CO2 laser can improve bond strength of resin cement to zirconia ceramic, and thus it could be considered as an appropriate alternative to conventional methods of zirconia surface treatment.
Multifunctional fractional carbon dioxide laser used in treatment of patients with acne and pigmentation from acne, as well as in the treatment of scars from different backgrounds, is an effective and safe method that causes statistically significant better effect of the treatment, greater patients’ satisfaction, minimal side effects and statistically better response to the therapy, according to assessments by the patient and the therapist.
Comedogenic and papular acne in our material were proportionately presented in 50% of cases, while the other half were the more severe clinical forms of acne - pustular inflammatory acne and nodulocystic acne that leave residual lesions in the form of second, third and fourth grade of scars. The experiences of our work confirm the world experiences that the best result with this method is achieved in dotted ice pick or V-shaped acne scars.
Among the patients, 92% showed a clinical response and 50% showed a complete response with a negative microscopic result. The factors that influenced a successful outcome were the type of onychomycosis and the thickness of the nail plate before treatment. The treatment regimen was well tolerated and there was no recurrence 3 months after the last treatment episode. The study followed up only 24 patients and there were no relevant treatment controls. Fractional carbon-dioxide laser therapy, combined with a topical antifungal agent, was effective in the treatment of onychomycosis. It should be considered an alternative therapeutic option in patients for whom systemic antifungal agents are contraindicated.
Fibroblast growth factor (FGF) 9 is secreted by both mesothelial and epithelial cells, and plays important roles in organ development and wound healing via WNT/β-catenin signaling. The aim of this study was to evaluate FGF9 expression and FGF-WNT/β-catenin signaling during wound healing of the skin. We investigated FGF9 expression and FGF-WNT/β-catenin signaling after laser ablation of mouse skin and adult human skin, as well as in cultured normal human epidermal keratinocytes (NHEKs) upon stimulation with recombinant human (rh) FGF9 and rh-transforming growth factor (TGF)-β1. Our results showed that laser ablation of both mouse skin and human skin leads to marked overexpression of FGF9 and FGF9 mRNA. Control NHEKs constitutively expressed FGF9, WNT7b, WNT2, and β-catenin, but did not show Snail or FGF receptor (FGFR) 2 expression. We also found that FGFR2 was significantly induced in NHEKs by rhFGF9 stimulation, and observed that FGFR2 expression was slightly up-regulated on particular days during the wound healing process after ablative laser therapy. Both WNT7b and WNT2 showed up-regulated protein expression during the laser-induced wound healing process in mouse skin; moreover, we discerned that the stimulatory effect of rhFGF9 and rhTGF-β1 activates WNT/β-catenin signaling via WNT7b in cultured NHEKs. Our data indicated that rhFGF9 and/or rhTGF-β1 up-regulate FGFR2, WNT7b, and β-catenin, but not FGF9 and Snail; pretreatment with rh dickkopf-1 significantly inhibited the up-regulation of FGFR2, WNT7b, and β-catenin. Our results suggested that FGF9 and FGF-WNT/β-catenin signaling may play important roles in ablative laser-induced wound healing processes.
In spite of the short incubation time, 24 lesions (70.6%) showed a complete response (CR) within three sessions of PDT (10 lesions a clinical CR and 14 lesions a clinical/histological CR). There were no significant side effects associated with the combination of ablative CO2 fractional laser and PDT. Ablative CO2 fractional laser may be considered an additional treatment option for reducing the incubation time of the photosensitizer in PDT.
Hypertrophic scars (HS) result from an imbalance between collagen biosynthesis and matrix degradation during wound healing. In this study a proteomics approach was used to compare the protein profiles of skin tissue obtained from patients with HS and healthy controls. One of the epidermal proteins, galectin-7 was markedly down-regulated in HS. Serum levels of galectin-7 in 27 patients with HS were less than 1/3 of those in 15 healthy controls. Tissue protein expression was subsequently evaluated using immunohistochemical staining on HS tissue and on serially-obtained control tissue during wound healing. Weaker galectin-7 immunoreactivity was detected along the cytoplasmic membrane of basal and suprabasal cells in samples from HS. In addition, galectin-7 was stained in the extracellular space of the upper papillary dermis in HS tissue. Ablative laser treatment, used to induce wound healing of healthy control tissue, demonstrated marked galectin-7 expression at the cytoplasmic membrane on days 3, 5, 14 and 21. Pronounced galectin-7 staining at the upper papillary dermis was detected on days 1, 3 and 10. These results suggest that the differences in galectin-7 expression and subcellular and extracellular distribution may be crucially involved in the pathogenic process of HS.
Three months after the last treatment, a greater decrease in Vancouver Scar Scale score was noted in the treated half of the scars, especially in terms of texture and thickness. Patients also expressed a significantly greater degree of satisfaction with the treated side as assessed using a subjective 4-point scale. Only one patient experienced any adverse effect, which was the development of hypertrophy, on the treated and untreated side of the scar. CO2 fractional laser is an effective treatment modality for surgical scars in the early postoperative period.
After the final treatment, average percentage changes of VSS were 28.2% for EYFL and 49.8% for CO2FL. Improvement was evident in terms of pliability, while insignificant in terms of vascularity and pigmentation. Based on physician's global assessment, mean grade of 1.8 for EYFL and 2.7 for CO2FL was achieved. Patient's subjective satisfaction scores paralleled the physician's objective evaluation. CO2FL is a potentially effective and safe modality for the treatment of hypertrophic scars, particularly in terms of pliability.
At 3 months after treatment, the mean grade of improvement based on clinical assessment was 2.64±0.76 for FPS, 2.60±0.68 for CO2 FS, and 2.94±0.83 for combination therapy (p=0.249). The mean grade of improvement was higher in patients who received treatment within 3 years of scar development (2.84±0.69) than in patients who received treatment >3 years after scar development (2.51±0.82; p=0.042). FPS and CO2 FS were both effective and safe for the treatment of scars, and can also be used together safely as a combination treatment. The proper laser device and proper treatment time should be decided considering various factors.
Complications included 2.3% herpes simplex outbreak, 4% persistent erythema past 2 weeks, four cases of prolonged edema to 5 days, one case of impetigo, and no evidence of dyspigmentation. Patient satisfaction data demonstrated no refunds at 12 months. Combination fractional laser resurfacing with short flap, high-Superficial muscular aponeurotic system rhytidectomy is a safe procedure with excellent patient satisfaction and clinical outcomes.
The mean age of enrolled patients was 57.5 ± 10.9 years and the gender ratio was 7 : 33. The face was the most commonly treated area, although the extremities are epidemiologically the most frequently affected areas. Two months after treatment, objective assessments performed by two independent dermatologists indicated more than 50% improvement in 36 patients (90%), compared with baseline. In addition, 33 patients (82.5%) were very satisfied or satisfied with just one session of CO(2) FL treatment. Although a few patients complained of long-standing erythema and postinflammatory hyperpigmentation, these problems spontaneously resolved within 2 months after the assessments. No other noticeable side effects were observed. CO(2) FL might be a very convenient and effective modality for treating IGH without significant side effects.
Objective and subjective improvement was estimated about 20-70% and 30-70%, respectively, without any erythema, permanent hyperpigmentation and other adverse effects. The important point is that, participants returned back to work after 4-7 days. The Fractional CO2 laser resurfacing can be used as a safe and efficacious method to treat depressed acne scar.
A 47 year-old woman presented with eight-month history of tattoo allergic reaction of eyebrows after botulinum toxin A injection that was resistant to oral, topical and intralesional injection of corticosteroids. Multiple sessions of treatment with CO2 fractional laser resulted in significant flattening of allergic papules and plaques as well as reduction of tattoo pigmentation.
The application of fractional CO2 laser can improve bond strength of resin cement to zirconia ceramic, and thus it could be considered as an appropriate alternative to conventional methods of zirconia surface treatment.
This experimental study was performed to demonstrate the effects of non-ablative fractional laser (NAFL) and ablative fractional laser (AFL). Twenty male Sprague-Dawley rats were used for the study. Three 2×2-cm-sized squares were tattooed on the abdomen of the animals. Each tattooed square was used for NAFL, AFL and control experiments. The NAFL and AFL treatment were performed with the same total energy of 12,000 mJ cm(-2). The laser treatments consisted of four sessions, with an interval of 3 weeks between sessions. The areas of tattooed skin were serially measured, and skin samples were obtained for histologic examination after 4 months of treatment. NAFL did not cause immediate skin shrinkage, but the size of the NAFL-treated skin was reduced by 4.3% after 4 months. In contrast, AFL caused immediate skin shrinkage (11.5% reduction), and the size was maintained at 9% reduction after 4 months. In histologic examination, the dermal collagen was arranged flat and parallel to the skin surface in the upper dermis, and regenerated collagen fibres were clearly noticed in both NAFL-and AFL-treated skin samples. Immunohistochemical stains showed well-regenerated type I and III collagen fibres. Western blot analysis of skin samples showed that type I/III collagen ratio was not significantly changed after fractional laser treatment. Electron microscopic studies aimed to evaluate the long-term micro-architecture of the collagen fibrils. AFL treatment reduced D-band periodicity by 5.2% and fibril diameter by 14.8%, although there was no statistically significant difference (p>0.05). Fractional laser treatment shrinks the skin surface area and regenerates collagen. The AFL treatment showed more profound skin changes than NAFL.
Two months after the last treatment, mean improvement scores, assessed by physicians, were significantly higher for those treated with half-body fractional CO(2) laser therapy followed by NB-UVB phototherapy, compared with those treated with NB-UVB alone (P=0·034). In addition, according to subjective assessment, the half-body laser treatment followed by NB-UVB showed significantly higher improvements compared with NB-UVB treatment alone (P=0·023). Noticeable adverse events, such as infection, scarring and Koebner phenomenon, were not found in any patient. This study suggests that fractional CO(2) laser therapy followed by NB-UVB phototherapy could be used effectively and safely as an alternative modality for the treatment of refractory vitiligo.
Mean Vancouver Scar Scale (VSS) scores were statistically significantly lower after laser treatment. Three months after CO(2) FS treatment of thyroidectomy scarring, 12 of 23 participants showed clinical improvement of more than 51% from 2 to 3 weeks after surgery. The mean grade of clinical improvement based on independent clinical assessment was 2.6 ± 0.9. Early postoperative CO(2) FS treatment of thyroidectomy scars is effective and safe.
Although they do not statistically differ, both treatments with nonablative fractional laser and ablative CO2 fractional laser showed a significant clinical and histopathologic improvement of striae distensae over pretreatment sites. These results support the use of nonablative fractional laser and ablative CO2 fractional laser as effective and safe reatment modalities for striae distensae of Asian skin. However, neither treatment showed any greater clinical improvement than the other treatment.
Striae distensae are dermal atrophic scars with epidermal thinning and decreased collagen and elastic fiber. There is no 'gold standard' treatment modality in the treatment of striae distensae. Collagen is a major extracellular matrix component and is important in wound healing. The ablative CO(2) fractional laser is effective in various cutaneous scars and this study was attempted to evaluate the effect of succinylated atelocollagen and ablative CO(2) fractional laser in the treatment of striae distensae. Participants were divided into two groups and received three laser treatments at a 4-week interval. Clinical improvement was evaluated by participants and two blinded physicians by observing the comparative photographs. Skin biopsies were randomly taken from six participants. The ablative fractional resurfacing laser was effective in the clinical improvement of striae distensae. Statistically significant differences were partly observed between the collagen and placebo groups. Clinical improvement scored by doctors showed more improvement in the collagen group. However, scoring by participants did not show significant differences between the collagen and placebo groups. In conclusion, the ablative fractional resurfacing laser is effective in the treatment of striae distensae and succinylated atelocollagen may also be effective for striae distensae treatment. However, to prove the effect of succinylated atelocollagen, further research with a larger group of participants is needed.
Atrophic facial acne scarring is a widely prevalent condition that can have a negative impact on a patient's quality of life. The appearance of these scars is often worsened by the normal effects of aging. A number of options are available for the treatment of acne scarring, including chemical peeling, dermabrasion, ablative or nonablative laser resurfacing, dermal fillers, and surgical techniques such as subcision or punch excision. Depending on the type and extent of scarring, a multimodal approach is generally necessary to provide satisfactory results. Resurfacing techniques correct surface irregularities, long-lasting dermal fillers address the volume loss resulting from acne, and sub-superficial musculoaponeurotic system (SMAS) face-lift procedures counter the soft tissue laxity and ptosis associated with aging. This article briefly reviews the evolution of individual approaches to treating atrophic acne scarring, followed by case examples illustrating results that can be achieved using a multimodal approach. Representative cases from patients in their 30s, 40s, and 50s are presented. In the author's clinical practice, multimodal approaches incorporating fractionated laser, injectable poly-L: -lactic acid, and sub-SMAS face-lift procedures have achieved optimal aesthetic outcomes, high patient satisfaction, and durability of aesthetic effect over time.
Ablative fractional CO(2) laser treatment resulted in superficial, mainly epidermal defects reaching at most the upper papillary dermis (0.1-0.3 mm), covered by a thin eschar and coated by a small zone of collagen denaturation. Tissue injury characteristics depended on spot size as well as the energy delivered. Microneedle treatment led to thin vertical skin fissures, reaching the middermis (up to 0.5 mm) and injuring dermal blood vessels, but without surrounding tissue necrosis. Both technologies are able to create small epidermal defects which allow to deliver isolated cells such as melanocytes to an epidermodermal site, with microneedle treatment having the advantage of lacking devitalized tissue and eventually enabling vascular access for the transplanted cells.
The number of treatments required for improvement of neck texture and laxity ranged from 1-3, with an average of 1.4. For skin texture, the mean score improved 62.9% (95% CI: 57.4%, 68.4%), skin laxity, 57.0% (53.2%, 60.8%), and rhytides, 51.4% (48.3%, 54.5%). For overall cosmetic outcome, the mean score improved 59.3% (55.1%, 63.5%) at two months post treatment. In this prospective study, AFP was both safe and effective for the treatment of neck laxity, rhytids and skin texture. The degree of improvement observed in wrinkling, texture and laxity after AFP coupled with the benign side effect profile has not been reported with previous trials of ablative laser resurfacing of the neck.
The 120 μm tip allows for the deepest enetration into facial skin with the least amount of surface area ablated. The 300 μm tip allows for an intermediate level of penetration into the dermis and an intermediate amount of surface ablation. The 1000 μm tip can be used to fully ablate epidermis as in traditional laser resurfacing. Traditional CO2 lasers ablate the entire epidermis, which provides excellent results at the price of prolonged healing times and erythema. These lasers worked with larger spot sizes, often as much as 2.25 mm, and at fluences of about 7-8 J/cm² . Fractional CO2 lasers focus the same amount of energy into the skin in microscopic thermal zones as small as 120 μm, which create fluences of nearly 100 times those of traditional lasers. This results in tissue ablation past the epidermis and through the papillary dermis into the reticular dermis in these narrow zones while leaving the surrounding epidermis intact. These areas of undisturbed tissue allow for more rapid healing. The theory is that the deep penetration into the reticular dermis allows for deep collagen neogenesis, which is good for rhytid improvement while maintaining a rapid healing time.
Evaluation of clinical results 2 months after treatment showed that 15 of the 35 patients (42.9%) demonstrated marked (51-75%) clinical improvement, 12 (34.3%) had moderate (26-50%) clinical improvement, five (14.3%) showed minimal (0-25%) improvement, and three (8.6%) showed near total (≥75%) improvement. Clinical improvement scores were less 4 months after the second CO(2) FS treatment (not statistically significant). The mean maximal depth of the necrotic column was 1,236.3 μm. A specimen obtained from the infraorbital area immediately after treatment showed formation of necrotic columns on the interfollicular skin. The use of CO(2) FS can have a positive therapeutic effect on periorbital syringomas.
Follow-up results 3 months after a single low-fluence, high-density treatment with CO2 FS showed that four of 10 participants had clinical improvement of 51% to 75% from baseline. After the high-fluence, low-density CO2 FS treatment, five of 10 patients demonstrated marked clinical improvements of more than 76%.Higher-energy, lower-density laser settings seem to be more effective than lowerenergy, higher-density settings for acne scars and enlarged pores, although our results do not constitute a conclusive comparison of the two different modes of CO2 FS.
Improvement scores considering the number of suppurative lesions revealed that 3 of the 12 patients demonstrated clinical improvement of grade 4. Seven had clinical improvement of grade 3 and two showed improvement of grade 2. Improvement scores in severity were also evaluated; 2 of the 12 patients showed clinical improvement of grade 4. Six demonstrated clinical improvement of grade 3 and four had clinical improvement of grade 2. No patient showed a worsening of suppurative lesions. Our observations demonstrated that the use of CO(2) FS did not make active suppurative lesions worse, and might have a therapeutic effect on suppurative diseases and their related scars. Lasers Surg. Med. 41:550-554, 2009. (c) 2009 Wiley-Liss, Inc.