# A Novel High‐Safety Filler with Potential Periosteal Enhancement: In Vivo Evaluation of Cross‐Linked Sodium Hyaluronate Gel with PVA Microspheres in Rat Models

## TL;DR

A new filler combining hyaluronate gel and PVA microspheres was tested in rats and showed good safety, structural support, and promotion of tissue growth over six months.

## Contribution

A novel PVA/HA filler was developed and shown to provide structural support and promote periosteal angiogenesis with minimal inflammation.

## Key findings

- The PVA/HA filler maintained structural support and shape retention for six months with no significant morphological changes.
- The filler promoted periosteal angiogenesis and collagen and elastic fiber proliferation.
- Low inflammatory responses were observed even with increased microsphere concentrations.

## Abstract

In recent years, the demand for sophisticated aesthetic solutions and the emergence of novel materials in cosmetic dermatology have increased substantially. However, these materials induce marked inflammatory reactions. To address this limitation, in this study, we developed a novel filler Cross‐Linked Sodium Hyaluronate Gel combined with Polyvinyl Alcohol Microspheres (PVA/HA filler) and systematically evaluated its effects on the periosteum and subcutaneous tissue in a rat model.

Ultrasound, histopathology, and molecular biological assays were employed to systematically assess the shape retention of the PVA/HA filler and its biological responses at 1, 3, and 6 months in the periosteum and subcutaneous tissues.

Experimental data demonstrated that the PVA/HA filler exhibited excellent structural support, with no significant morphological changes observed over the 6‐month observation period. Notably, the filler effectively promoted periosteal angiogenesis and enhanced proliferation of collagen and elastic fibers. Furthermore, it maintained low inflammatory responses, even with increased microsphere concentrations in the PVA/HA formulation.

The novel PVA/HA filler demonstrated strong structural support in both the periosteum and subcutaneous tissue. The filler provides enhanced periosteal angiogenesis, promotes periosteal thickening, and stimulates collagen fiber formation, while exhibiting minimal inflammation, high safety, and no risk of hyperplasia.