Comparison of Vestibular Depth Relapse and Wound Healing After Reconstructive Preprosthetic Surgery Using Cryopreserved Amniotic Membrane and Acellular Dermal Matrix - A Comparative Study

Introduction to Amniotic Membranes in Maxillofacial Surgery-A Scoping Review

Background: Amniotic membrane (AM) holds significant promise in various medical fields due to its unique properties and minimal ethical concerns. This study aims to explore the diverse applications of the human amniotic membrane (HAM) in maxillofacial surgery. Methodology: A comprehensive search was conducted on databases, namely Google Scholar, PubMed, and Scopus, from January 1985 to March 2024. Articles in English, Polish, and Spanish were included, focusing on keywords related to amniotic membrane and oral surgery. Results: Various preservation methods for HAM were identified, namely fresh, decellularized, cryopreserved, lyophilized, and air-dried formats. Clinical studies demonstrated the efficacy of HAM in repairing oral mucosal defects, vestibuloplasty, oronasal fistula closure, cleft palate treatment, bone defect repair, and medication-related osteonecrosis of the jaw (MRONJ). Surgeon evaluations highlighted the ease of handling but noted challenges in suturing and stability during application. Conclusions: Amniotic membranes offer a versatile and effective option in maxillofacial surgery, promoting wound healing, reducing inflammation, and providing a scaffold for tissue regeneration. Further research, including randomized trials and comparative studies, is warranted to validate the efficacy and optimize the utilization of HAM in clinical practice.

Digitally designed stent-assisted soft-tissue management after jaw reconstruction: a prospective cohort study

OBJECTIVES

A digitally designed stent was invented to assist vestibuloplasty and free gingival graft (FGG) after jaw reconstruction. This study aimed to compare the effects of conventional soft-tissue management comprising vestibuloplasty combined with FGG and modified soft-tissue management using a digitally designed stent on the vestibular sulcus depth (VD), keratinised-tissue width (KTW) and peri-implant tissue health in patients undergoing jaw reconstruction.

MATERIALS AND METHODS

This prospective cohort study enrolled patients who underwent jaw reconstruction using a fibular flap, iliac flap, or onlay bone graft followed by implant-supported rehabilitation at the Peking University School and Hospital of Stomatology between May 2019 and July 2022. Patients in the stent group received digitally designed stents following vestibuloplasty combined with FGG for peri-implant soft-tissue management. Patients in the control group underwent a conventional vestibuloplasty combined with FGG. VD and KTW were evaluated immediately after implant loading (T2) and 1 year after implant loading (T3), and the atrophy rates of VD and KTW were calculated. Peri-implant clinical parameters were evaluated at T3. Comparisons between the groups were performed using the Mann-Whitney U test. The effects of age, sex, primary disease, reconstruction type, reconstructed jaw and the number and location of implants on VD and KTW were evaluated using linear regression analysis.

RESULTS

There were no significant differences in the atrophy rates of VD and KTW between the stent and control groups at T2 and T3 (both P ≥ 0.05). There were no significant differences in peri-implant clinical parameters between the stent and control groups at T3 (P ≥ 0.05). Reconstruction type, location of implants and primary disease influenced VD, and reconstruction type and age influenced KTW.

CONCLUSIONS

There was no significant difference in the maintenance of VD and KTW after jaw reconstruction between soft-tissue management using a digitally designed stent and the conventional method. Further, digitally designed stents do not affect peri-implant tissue health.

CLINICAL RELEVANCE

Digitally designed stents can simplify clinical procedures without adverse effects on peri-implant tissue health, but they do not promote keratinized mucosa augmentation and vestibuloplasty.

Acellular Biomaterials Associated with Autologous Bone Marrow-Derived Mononuclear Stem Cells Improve Wound Healing through Paracrine Effects

Wound healing is a complex process of repair that involves the interaction between different cell types and involves coordinated interactions between intracellular and extracellular signaling. Bone Marrow Mesenchymal Stem Cells (BMSCs) based and acellular amniotic membrane (AM) therapeutic strategies with the potential for treatment and regeneration of tissue. We aimed to evaluate the involvement of paracrine effects in tissue repair after the flap skin lesion rat model. In the full-thickness flap skin experiment of forty Wistar rats: A total of 40 male Wistar rats were randomized into four groups: group I: control (C; n = 10), with full-thickness lesions on the back, without (BMSCs) or AM (n = 10); group II: injected (BMSCs; n = 10); group III: covered by AM; group IV-injected (AM + BMSCs; n = 10). Cytokine levels, IL-1, and IL-10 assay kits, superoxide dismutase (SOD), glutathione reductase (GRs) and carbonyl activity levels were measured by ELISA 28th day, and TGF-β was evaluated by immunohistochemical, the expression collagen expression was evaluated by Picrosirius staining. Our results showed that the IL-1 interleukin was higher in the control group, and the IL-10 presented a higher mean when compared to the control group. The groups with BMSCs and AM showed the lowest expression levels of TGF-β. SOD, GRs, and carbonyl activity analysis showed a predominance in groups that received treatment from 80%. The collagen fiber type I was predominant in all groups; however, the AM + BMSCs group obtained a higher average when compared to the control group. Our findings suggest that the AM+ BMSCs promote skin wound healing, probably owing to their paracrine effect attributed to the promotion of new collagen for tissue repair.

Acellular dermal matrix in reconstructive surgery: Applications, benefits, and cost

Modern tissue engineering has made substantial advancements that have revolutionized plastic surgery. Acellular dermal matrix (ADM) is an example that has gained considerable attention recently. ADM can be made from humans, bovines, or porcine tissues. ADM acts as a scaffold that incorporates into the recipient tissue. It is gradually infiltrated by fibroblasts and vascularized. Fortunately, many techniques have been used to remove cellular and antigenic components from ADM to minimize immune system rejection. ADM is made of collagen, fibronectin, elastin, laminin, glycosaminoglycans, and hyaluronic acid. It is used in critical wounds (e.g., diabetic wounds) to protect soft tissue and accelerate wound healing. It is also used in implant-based breast reconstruction surgery to improve aesthetic outcomes and reduce capsule contracture risk. ADM has also gained attention in abdominal and chest wall defects. Some studies have shown that ADM is associated with less erosion and infection in abdominal hernias than synthetic meshes. However, its higher cost prevents it from being commonly used in hernia repair. Also, using ADM in tendon repair (e.g., Achilles tendon) has been associated with increased stability and reduced rejection rate. Despite its advantages, ADM might result in complications such as hematoma, seroma, necrosis, and infection. Moreover, ADM is expensive, making it an unsuitable option for many patients. Finally, the literature on ADM is insufficient, and more research on the results of ADM usage in surgeries is needed. This article aims to review the literature regarding the application, Benefits, and costs of ADM in reconstructive surgery.