Functionally graded membrane: A novel approach in the treatment of gingival recession defects

Efficacy of amniotic membrane with coronally advanced flap in the treatment of gingival recession: an updated systematic review and meta-analysis

OBJECTIVES

This systematic review aims to evaluate the efficacy of combining the amniotic membrane (AM) with the coronally advanced flap (CAF) in the treatment of Miller class I and II gingival recession (GR).

METHODS

The protocol of this updated PRISMA-compliant systematic review was registered in PROSPERO (CRD42023431501). The following treatment outcomes were recorded; recession depth (RD), recession width (RW), width of keratinized gingiva (WKG), and clinical attachment level (CAL). We searched the following databases: MEDLINE, Cochrane Library, Google Scholar, EMBASE, Web of Science, and Science Direct.

RESULTS

Two independent reviewers screened the selected articles. Twenty-two eligible articles were extracted, with 689 sites of GR in 481 patients. No statistically significant difference was found in RD, RW, WKG, and CAL between (AM&CAF) in comparison to control groups. However, the subgroup analysis showed statistically significant differences in RD between the (AM & CAF) group v/s (CAF) alone (P = 0.004). Moreover, the subgroup analysis of the WKG showed statistically significant differences between (AM & CAF) v/s (CAF&CM) (p = 0.04). Additionally, a statistically significant difference was found in the subgroup analysis of CAL between both (AM & CAF) group v/s (CAF) alone (p = 0.0009).

CONCLUSION

With the limitations of this meta-analysis due to short follow-up periods (6 months), the AM can be considered a viable treatment option for GR defects with satisfactory treatment outcomes comparable to other previously investigated treatment modalities.

CLINICAL SIGNIFICANCE

While AM showed various beneficial properties as an ideal membrane for the coverage of GR, future studies are required to completely understand the potential application of AM in the treatment of GR.

Emerging Strategies for the Biofabrication of Multilayer Composite Amniotic Membranes for Biomedical Applications

The amniotic membrane (AM) is the innermost part of the fetal placenta, which surrounds and protects the fetus. Due to its structural components (stem cells, growth factors, and proteins), AMs display unique biological properties and are a widely available and cost-effective tissue. As a result, AMs have been used for a century as a natural biocompatible dressing for healing corneal and skin wounds. To further increase its properties and expand its applications, advanced hybrid materials based on AMs have recently been developed. One existing approach is to combine the AM with a secondary material to create composite membranes. This review highlights the increasing development of new multilayer composite-based AMs in recent years and focuses on the benefits of additive manufacturing technologies and electrospinning, the most commonly used strategy, in expanding their use for tissue engineering and clinical applications. The use of AMs and multilayer composite-based AMs in the context of nerve regeneration is particularly emphasized and other tissue engineering applications are also discussed. This review highlights that these electrospun multilayered composite membranes were mainly created using decellularized or de-epithelialized AMs, with both synthetic and natural polymers used as secondary materials. Finally, some suggestions are provided to further enhance the biological and mechanical properties of these composite membranes.

Nanomaterials for Periodontal Tissue Regeneration: Progress, Challenges and Future Perspectives

Bioactive nanomaterials are increasingly being applied in oral health research. Specifically, they have shown great potential for periodontal tissue regeneration and have substantially improved oral health in translational and clinical applications. However, their limitations and side effects still need to be explored and elucidated. This article aims to review the recent advancements in nanomaterials applied for periodontal tissue regeneration and to discuss future research directions in this field, especially focusing on research using nanomaterials to improve oral health. The biomimetic and physiochemical properties of nanomaterials such as metals and polymer composites are described in detail, including their effects on the regeneration of alveolar bone, periodontal ligament, cementum and gingiva. Finally, the biomedical safety issues of their application as regenerative materials are updated, with a discussion about their complications and future perspectives. Although the applications of bioactive nanomaterials in the oral cavity are still at an initial stage, and pose numerous challenges, recent research suggests that they are a promising alternative in periodontal tissue regeneration.

Functionally Graded Bioactive Composites Based on Poly(vinyl alcohol) Made through Thiol-Ene Click Reaction

Functionally graded materials (FGMs) composed of a polymer matrix embedded with calcium phosphate particles are preferred for bone tissue engineering, as they can mimic the hierarchical and gradient structure of bones. In this study, we report the design and development of a FGM based on thiolated poly(vinyl alcohol) (TPVA) and nano-hydroxyapatite (nano-HA) with graded bioactivity, cell compatibility, and degradability properties that are conducive for bone regeneration. The polymer matrix comprises crosslinked poly(vinyl alcohol) with ester and thioether linkages formed via the thiol-ene click reaction, avoiding undesired additives and byproducts. Freshly precipitated and spray-dried HA was mixed with the TPVA hydrogel, and layers of varying concentrations were cast. Upon lyophilization, the hydrogel structure yielded porous sheets of the graded composite of TPVA and nano-HA. The new FGM showed higher values of tensile strength and degradation in phosphate buffer saline (PBS) in vitro, compared to bare TPVA. The bioactive nature of the FGM was confirmed through bioactivity studies in simulated body fluid (SBF), while cytocompatibility was demonstrated with human periodontal ligament cells in vitro. Cumulatively, our results indicate that based on the composition, mechanical properties, bioactivity, and cytocompatibility, the fabricated TPVA-HA composites can find potential use as guided bone regeneration (GBR) membranes.