Duration of bite force reduction following a single injection of botulinum toxin in the masseter muscle bilaterally: A one-year non-randomized trial.

BACKGROUND: Previous studies concerning the effect of botulinum toxin in masseter muscle have mainly reported effects observed through inspection of facial features or differences in pain levels. One systematic review of studies utilizing objective measurements reported that long-term muscular effect of botulinum neurotoxin injections into masseter muscle was inconclusive. OBJECTIVE: To evaluate the duration of reduced maximal voluntary bite force (MVBF) after botulinum toxin intervention. METHODS: The intervention group was comprised of individuals seeking aesthetic treatment for masseter reduction (n = 20), the reference group (n = 12) comprised of individuals with no intervention. Intervention through 25 units of Xeomin® (Merz Pharma GmbH & Co KGaA, Frankfurt am Main, Germany) botulinum neurotoxin type A injected into the masseter muscles bilaterally (totalling 50 units). A reference group did not receive any intervention. MVBF was measured in Newtons using a strain gauge meter at the incisors and first molars. MVBF was measured at baseline, at 4 weeks, 3 months, 6 months, and after 1 year. RESULTS: Both groups were similar in terms of bite force, sex and age at baseline. MVBF remained similar compared to baseline in the reference group. At 3 months, a significant reduction at all measurement points was observed in the intervention group; at 6 months, this reduction was no longer significant. CONCLUSION: A single intervention of 50 units of botulinum neurotoxin results in a reversible MVBF reduction of at least 3 months, although a visually discernable reduction may be more long-lasting.

Efficacy and safety of hyaluronic acid filler on the treatment of horizontal neck lines.

BACKGROUND: Injection of hyaluronic acid fillers (HA) fillers for horizontal neck line correction and rejuvenation has gained popularity in recent years despite conflicting reports on its efficacy and safety. Most published reports are retrospective studies that commonly use the sharp needle technique. In this prospective study, we therefore aimed to determine the efficacy and safety of an HA filler (Belotero Balance®, Merz Aesthetics) on the treatment of horizontal neck lines by blunt cannula injection technique. MATERIALS AND METHODS: Thirty subjects were enrolled and treated with HA filler injections on the neck region using a blunt cannula injection technique into the deep dermis. Standardized photographic documentation was done at baseline, immediately after injection, and at 2-week, 1-, 3-, and 6-month follow-up after treatment. The rejuvenation effect was graded by the patients themselves and two blinded dermatologists using comparative photographs. Side effects were likewise recorded at each follow-up visit. RESULTS: All 30 subjects completed treatment and attended every follow-up visit. The study participants comprised both females and males aged 20-69 years with mild, moderate, and severe neck lines based on the Horizontal Neck Wrinkle Severity Scale (HNWS) (Plast Reconstr Surg Glob Open, 2019, 7, 2366). All patients received approximately 3 ml of HA fillers for the entire treatment area. Both patient and physician ratings revealed peak benefits at 1-month post-treatment, with a significant decline at 3 months, which was sustained until 6 months after the procedure. Only one patient developed bruising related to the treatment, which resolved spontaneously without any additional medication. CONCLUSION: The study demonstrated efficacy in improving the appearance of horizontal neck lines after one session of HA filler injection. The results showed peak improvement at 1 month, but with sustained rejuvenation effects up to 6 months after injection.

Efficacy and Safety of Using Noninsulated Microneedle Radiofrequency Alone Versus in Combination with Polynucleotides for the Treatment of Melasma: A Pilot Study.

INTRODUCTION: This split-face, double-blind, randomized controlled study investigated the efficacy and safety of using a microneedling radiofrequency (RF) device with polynucleotides (PN) versus RF alone for the treatment of melasma. METHODS: Thirty adult participants with melasma (Fitzpatrick skin types III-V) received three treatments with an invasive, bipolar, pulsed-type microneedling RF device on both sides of the face. The treatment sessions occurred once every 2 weeks. The hemifaces of each participant were designated for treatment and control with PN and normal saline solution (NSS), applied after treatment with RF. Measurements were made of melanin index (MI), erythema index (EI), skin roughness (by the Antera 3D system), modified melasma area severity index (mMASI) for each hemiface, and patients' self-assessed improvement. These occurred at baseline and again following the final treatment (2 weeks and 1, 2, 3, and 6 months after). Mean values were obtained for MI, EI, skin roughness, and mMASI. A generalized estimating equation (GEE) was used to compare the obtained values for the outcome measures across all assessment points. RESULTS: All patients were women (mean age, 43.2 ± 7.0 years). Mixed melasma predominated (61.5%; n = 16), and the mean duration of melasma was 8.9 ± 6.5 years. Twenty-six participants were followed up to the 6-month assessment point. Significant improvements were observed from baseline in MI, skin roughness, and mMASI scores for both the PN and control sides at 6 months, with no statistically significant differences between sides. Patients' self-assessed improvement scores also showed a positive trend. Melasma recurrence was observed in three patients at 2, 3, and 4 months after the last treatment session (10% recurrence rate). CONCLUSIONS: The combination of an invasive, bipolar, pulsed-type microneedling RF with PN is not superior compared with microneedling RF alone in the treatment of melasma. Microneedling RF may be considered as safe and efficacious for the improvement of skin roughness, and as an adjunctive treatment option for melasma. CLINICAL TRIAL REGISTRATION: This study was registered on ClinicalTrials.gov and assigned NCT number TCTR20210804002.

Efficacy and Safety of Using Noninsulated Microneedle Radiofrequency Alone versus in Combination with Polynucleotides for Treatment of Periorbital Wrinkles.

INTRODUCTION: A few studies have evaluated the efficacy and safety of noninsulated radiofrequency microneedling (RFMN) to treat periorbital wrinkles in Asian patients. Recently, wound healing accelerators, polynucleotides (PNs), have received attention in wound management. However, their efficacy and safety have not been fully elucidated following RFNM. This study aimed to evaluate the efficacy and safety of noninsulated RFMN for periorbital wrinkles and the synergistic effect of PNs after RFMN. METHODS: Thirty subjects with Fitzpatrick skin types III to V and facial wrinkles (Fitzpatrick grades I and II) were enrolled. All volunteers were treated over the entire face with noninsulated RFMN for three sessions at 2-week intervals. The left and right sides of each patient's face were randomly assigned to receive PNs (treatment group) or normal saline solution (control group). The indentation and maximum depth of wrinkles were objectively measured using Antera 3D. Subjective self-evaluations were obtained at baseline, 2 weeks after the third treatment, and at 1, 2, 3, and 6 months after the final treatment. In addition, pain scores, immediate reactions, and other adverse effects were evaluated. RESULTS: Twenty-nine subjects completed the treatment protocol. Most presented with grade II wrinkling (69%). At 2-month follow-up, Antera 3D image analysis revealed faster improvement for the treatment group. At 6-month follow-up, the majority of subjects reported an improvement of 25-75% in their periorbital wrinkles. The average pain score was 2.2 out of 10. No serious adverse events (infection, pigmentary alteration, persistent erythema, or scarring) were observed. CONCLUSIONS: Noninsulated RFMN is safe and effective for treating periorbital wrinkles and can be used as a modality for transdermal drug delivery. Topical polynucleotides as an adjunctive treatment provide additional benefits for periorbital wrinkle treatment. TRIAL REGISTRATION NUMBER: TCTR20201105007.