BACKGROUND Because the anatomic mechanisms underlying the formation of the midcheek groove are unclear, treatments to date have resulted in unsatisfactory outcomes. OBJECTIVE This study investigated the anatomical foundation of the midcheek groove and evaluated appropriate treatment methods. MATERIALS AND METHODS Six cadaver hemifacial specimens were subjected to gross anatomic dissection and 6 to P45 sheet plastination. Based on the anatomic results, the area under the orbicularis oculi muscle (OOM) was selected for deep filling. Patients were evaluated by measuring 3D depth, regrading, and self-assessment. RESULTS The medial band was observed to be an important structure of the OOM, with the facial projection overlapping the midcheek groove trace. Two of the 6 P45 specimens were found to have compact fibroelastic bundles (CFBs) between the medial band and the dermis. Deep filling of the area under the OOM significantly reduced the depth of each section in all 34 patients (p < .001). Grades 3 and 4 midcheek grooves were downgraded distinctively. Most subjects expressed satisfaction with outcomes. CONCLUSION Formation of the midcheek groove is associated with the passage of CFBs. Deep filling of the area under the OOM effectively improves the midcheek grooves.

Background As a derivative of adipose tissues, stromal vascular fraction gel has been widely used in facial soft tissue filling, but it still does not achieve the expected effect in forehead filling. The reason may be related to the corrugator muscles movements. Objectives The authors aimed to evaluate the effect of botulinum toxin-A (BTX-A) on the retention rate of stromal vascular fraction gel by limiting the corrugator muscles movements and provide a theoretical basis that short-term inhibition of movement in the affected area could improve the effects of the fat graft. Methods From January 2019 to June 2021, patients with stromal vascular fraction gel facial filling (including frontal and temporal parts) were selected. According to whether or not BTX-A treatment was received, patients were divided into the injected and the non-injected groups. A questionnaire and the global aesthetic improvement scale (GAIs) were administered with two-dimensional (2D) photos. The retention rate and curvature were calculated with three-dimensional (3D) images using the Artec Studio 13 Professional (Artec Europe Sàrl, Senningerberg, Luxembourg) and MATLAB (Natick, MA) software. Results The graft retention, forehead curvature, and GAIs scores were all higher in the injected group than in the non-injected group (P &lt; 0.01). In the questionnaire, the injected group also showed a more satisfactory attitude towards the treatment effect and were more willing to recommend the treatment to their friends. Conclusions BTX-A injection can improve the retention rate of prefrontal stromal vascular fraction gel filling with higher satisfaction and better postoperative effects.