Abstract

Objectives: 1: Define temporal hollowing and assess the severity. 2: Describe and compare different treatment techniques for injecting the temporal fossa, using poly-L-lactic acid. 3: Evaluate clinical endpoints up to week 38 post-injection. Introduction: Poly-L-lactic acid (PLLA) can be used to improve the aesthetics of the temporal fossa but is usually only deposited within the visible area of the temporal hollows. However, it remains possible that extending the treatment area posterior to the hairline may provide a greater lifting effect. Therefore, this study aimed to assess the efficacy and safety of two techniques (i.e., traditional versus extended) of injecting PLLA for aesthetic improvement of the temporal fossae. Materials / method: A prospective, randomized-controlled clinical trial was conducted. Twenty-four subjects with bilateral temporal hollowing were randomized in a 1-to-1 ratio to either the traditional or extended technique. Subjects received three treatments (Baseline, Week 7, Week 14) and were observed at follow-up visits at Weeks 20, 26 and 38. Assessments included the Global Aesthetic Improvement Scale (GAIS), a four-point photo-numeric Temple Volume Deficit Scale (TVDS), quantification of lifting and volumizing effects, patient satisfaction, and adverse events. Results: A greater lifting effect was observed with participants treated with the extended technique, compared to those treated with the traditional technique (p < 0.001). Furthermore, greater treatment effects were evidenced by a greater mean decrease in TVDS scores with the extended technique compared to the traditional technique. Regardless of injection technique, at week 26, 91.30% (21/23) of subjects at least improved on the GAIS, and there was a low frequency of adverse events. Conclusion: PLLA is a safe and effective treatment for improving the aesthetic appearance of the temporal fossae. Aesthetic improvement can be maximized using an extended injection technique.