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.

Management of post-Mohs surgical wounds with a hypothermically stored amniotic membrane: a case series.

OBJECTIVE: The aim of this case series is to present an alternative approach to managing post-Mohs Micrographic Surgery (Mohs) wounds with hypothermically stored amniotic membrane (HSAM). METHOD: A case series of patients with post-Mohs wounds is presented, with four patients referred for hard-to-heal wounds following a Mohs procedure that was performed 1-3 months previously. All wounds underwent weekly assessment, debridement, and application of HSAM and secondary dressings. Treatment also included management of bioburden, proper skin care and compression therapy for lower extremity wounds. RESULTS: This case series of seven wounds consisted of four females and three males with a mean age of 87.6 years. Mean wound size at first application of HSAM was 1.34±1.20cm2. All wounds closed, with an average time to wound closure of 43.7±27.1 days. Patients received an average of 4.6±2.5 HSAM applications. The four post-Mohs wounds with a history of being hard-to-heal had an average time to wound closure of 35.5±16.3 days, with an average duration of 86.5±32.4 days prior to the first HSAM application. CONCLUSION: The results of this case series suggest that use of HSAM may provide an alternative approach to managing post-Mohs wounds. In addition, these findings suggest that HSAM may be of greatest benefit when applied early after Mohs surgery.

Real-life experience on the effectiveness of conjunctival flap and amniotic membrane graft in the treatment of refractory fungal corneal ulcer.

PURPOSE: To evaluate and compare the results of the conjunctival flap (CF) and cryopreserved amniotic membrane graft (AMG) in the management of fungal corneal ulcers either with complications or non-responsive to medical treatment. STUDY DESIGN: A retrospective observational study. METHODS: Medical records of 30 patients with culture-positive fungal corneal ulcer treated with either CF or AMG (15 eyes in each group) in real world settings were retrieved for analysis. After the surgical procedure, patients were followed up on days 1, 7, 14, 21, 30, 60, 90, 120, and 180 to explore the outcomes of the operations along with complications. RESULTS: Infecting fungi were of genus Fusarium (n = 11), Aspergillus (n = 10), Mucor (n = 4) and Penicillium (n = 10). The most common indication was resistant ulcer with perforation. After the procedure, epithelization was completed in 11(73.33%) patients in the CF, and 13 patients in the (86.67%) AMG group. Visual acuity improvement was significantly better in the latter group (CF: 1 [6.67%] vs. AMG: 7 [46.67%], p = 0.023). Flap failure occurred in 4 patients (26.67%) from the CF and 2 (13.33%) from the AMG group. No significant differences were found between the two groups regarding success rate (p = 0.651), epithelialization time (p = 0.691), healing of corneal ulcer (p = 0.651), and postoperative stability (p = 0.651) of the flaps. CONCLUSIONS: CF and AMG are both effective for the management of refractory fungal corneal ulcers. However, AMG appears to improve visual acuity better than CF.

Evaluation of Regenerative Efficacy of Amnion and Chorion Membrane in Treatment of Mandibular Molar Furcation Defects: A Clinico-radiographic Study.

AIM: Amnion and chorion membranes possess unique inherited biological properties that enhance wound healing and may accelerate periodontal regeneration. The present study aims to evaluate and compare the efficacy of amnion and chorion membranes in the treatment of furcation defects. MATERIALS AND METHODS: A total of 20 patients were selected and were randomly allocated to group I and group II with 10 subjects in each group. Amnion and chorion membranes are placental-derived membranes that accelerate regeneration by having natural growth factors with their antimicrobial and inflammation reduction properties. Group I was treated using bone grafting with decalcified freeze-dried bone allograft (DFDBA) and placement of amnion as a membrane for guided tissue regeneration (GTR) whereas group II was treated using bone grafting with DFDBA and placement of chorion as a membrane for GTR. The patients were followed for clinical and radiographic parameters and were evaluated between 3 and 6 months after surgery. RESULT: In intragroup comparison, a significant difference was evident in both the groups for all the clinical and radiographic parameters within the groups. (p = 0.01) This means both amnion and chorion membranes showed statistically significant regenerative efficacy. In intergroup comparison, the results show that all the clinical parameters and radiographic parameters show no significant difference between the groups. CONCLUSION: The amnion and chorion membranes had similar regenerative efficacy in combination with DFDBA in patients with buccal degree II furcation defects in mandibular molars. CLINICAL SIGNIFICANCE: The amnion and chorion membranes have shown significant improvement in clinical and radiographic parameters when used for the treatment of buccal degree II furcation defects in mandibular molars. How to cite this article: Mallapragda S, Gupta R, Gupta S, et al. Evaluation of Regenerative Efficacy of Amnion and Chorion Membrane in Treatment of Mandibular Molar Furcation Defects: A Clinico-radiographic Study. J Contemp Dent Pract 2024;25(2):160-167.

[Modified mini-SLET for treatment of complex cases in pterygium surgery]. / Modifizierte Mini-SLET zur Behandlung von komplexen Fällen in der Pterygiumchirurgie.

BACKGROUND: The major problem associated with the benign but destructive growing pterygium is the high recurrence rate. A new surgical technique to lower recurrence rates is minor ipsilateral simple limbal epithelial transplantation (mini-SLET), where the regeneration potential of limbal stem cells is used in combination with amniotic membrane transplantation (AMT) for surgical reconstruction. The aim of this study is to assess the surgical outcome of the mini-SLET technique with tenonectomy, mitomycin C, and AMT as used in the authors' hospital. MATERIALS AND METHODS: A total of 16 eyes from 15 patients undergoing mini-SLET after surgical pterygium removal with tenonectomy, mitomycin C, and AMT were analyzed retrospectively. Two different groups of pterygia were enrolled: group 1 included recurrent pterygia (n = 10) and group 2 comprised primary large pterygia such as double-head pterygia (n = 6). In addition to assessment of best corrected visual acuity and compete ophthalmological examination, preoperative slip-lamp examination with photo documentation served to calculate the corneal size of the pterygium head using VISUPAC software (Zeiss, Oberkochen, Germany). Postoperatively, best corrected visual acuity and slit-lamp examination were routinely evaluated. The surgical outcome was defined by the postoperatively achieved best corrected visual acuity, restoration of the ocular surface, recurrence rate, and rate of postoperative complications. RESULTS: Median follow-up in all patients was 27 months; in groups 1 and 2 it was 30.7 and 25.3 months, respectively. No recurrence developed in 15 eyes (93.75%). Only one group 1 patient (6.25%) suffered a recurrent lesion after 10 months. Postoperatively, logMAR visual acuity did not change significantly. During follow-up, complications were limited to one case of early wound dehiscence. CONCLUSION: Mini-SLET in combination with tenonectomy, mitomycin C, and AMT enables good surgical reconstruction of the ocular surface, and almost complete healing in the sense of restitutio ad integrum is possible. The results of the present study have shown the technique's effectiveness for recurrence prevention.

Amniotic membrane dressings for treatment of aplasia cutis in newborns.

BACKGROUND: Aplasia cutis congenita (ACC) is a rare congenital skin defect characterized by a focal or extensive absence of the epidermis, dermis, and occasionally, subcutaneous tissue. When the wound caused by this defect is wide or deep, various treatments are used, including skin grafting. The amniotic membrane (AM) is a biological dressing that facilitates re-epithelialization as it contains mesenchymal cells and numerous growth factors. OBJECTIVE: To report the efficacy of AM dressings in treating the skin defects of ACC. METHOD: This study was conducted on five neonates diagnosed with ACC born between 2018 and 2022, referred to the Children's Medical Center in Tehran, Iran. AM dressings were applied on wounds larger than 1 cm2. The wounds were assessed weekly and, if required, an additional AM dressing was applied. RESULTS: The skin defects gradually re-epithelialized after application of the AM. The complete healing process took around 3.5 weeks on average. No hypertrophic scarring was observed. CONCLUSION: The application of AM dressing resulted in satisfactory cosmetic outcomes, with no hypertrophic scar formation. Complete healing occurred in all cases except one. The length of the hospital stay ranged from 2 to 6 weeks, depending on the size of the wound.

Debulking corneal biopsy with tectonic amniotic membrane transplantation in refractory clinically presumed fungal keratitis.

The treatment of fungal keratitis (FK) is challenging due to the subacute indolent course, and initial misdiagnosis. In this retrospective case series, we highlight both the diagnostic and therapeutic roles of corneal biopsy together with amniotic membrane transplantation (AMT) in patients with refractory clinically presumed FK. Debulking biopsy and tectonic AMT were performed during the initial presentation. Biopsy specimens were sent for KOH smears and cultures. After KOH smears confirmed the presence of fungal elements, topical voriconazole 1% was prescribed for the first 72 h then tailored according to the clinical response and the culture results. The outcome measures were complete resolution of infection and restoration of corneal integrity. Cases associated with culture proven bacterial keratitis were excluded. Twelve cases were included in the study. KOH smears confirmed the presence of fungal growth in all specimens. Cultures grew Aspergillus in 6/12 cases, sensitive to voriconazole (5/6) and amphotericin (3/6); Fusarium (4/12), sensitive to both voriconazole and amphotericin; and no growth in 2/12 cases. Amphotericin 0.15% eye drops were added to the 7 cases with proven sensitivity and to the remaining 2 culture negative cases. Gradual resolution of infection was seen in all cases after 35.6 ± 7.8 days. In FK, a debulking biopsy simultaneously with AMT help decrease the microbial load, suppress the inflammatory process, support the corneal integrity, confirm the presence of fungal pathogen.

Management of grade II and III furcation defects with intramarrow penetration along with indigenously prepared DFDBA and amniotic membrane: a clinical and radiographic study.

Managing furcation defects constitutes a problem in successful periodontal therapy. Guided tissue regeneration (GTR) is the mainstay for the management of such defects but is expensive. This study makes use of indigenously prepared demineralized freeze-dried bone allograft (DFDBA) and amniotic membrane (AM) as a cost-effective alternative. The purpose of the study was to compare the clinical outcome of grade II and III furcation defects with and without using indigenous DFDBA and AM prepared at Central Tissue Bank, MAIDS. 18 systemically healthy patients with chronic periodontitis displaying either grade II or III furcation defects were treated with open flap debridement (OFD) + intramarrow penetration (IMP) (control group) and OFD + IMP + DFDBA + AM (test group). The clinical and radiographic parameters were recorded at 3 and 6 months postoperatively. All parameters were statistically analyzed. Both treatment modalities resulted in improvement in all clinical variables evaluated. Radiographic dimensions evaluating bone fill showed a statistically significant difference in the test group compared to the control group. Within the limitations of this study, data suggest GTR using indigenously prepared DFDBA and amniotic membrane to be an economical and viable option for treating furcation defects.

Dehydrated human amnion/chorion membrane allograft with spongy layer to significantly improve the outcome of chronic non-healing wounds.

We investigated the healing effect of a new dehydrated amnion/chorion membrane with a spongy layer over a 30-month period in 32 patients with 53 chronic non-healing wounds of different aetiologies. Wounds with <40% surface reduction after 4 weeks of best wound treatment underwent weekly allograft application by a certified wound specialist based on national guidelines and a standardised protocol until complete healing or definite treatment interruption. The main outcome measure was the percentage of wound surface reduction from baseline calculated using digital planimetry follow-up photographs. Overall, 38 (71.7%) wounds presented a favourable outcome (70%-100% area reduction), with 35 (66%) completely healing over a median time of 77 days (range 29-350 days). Favourable outcomes were observed in 75% of traumatic wounds, surgical wounds, venous leg ulcers and pressure injuries, as well as in 50% of ischaemic wounds. Wounds being present <12 months were significantly more likely to have a favourable outcome than more long-standing wounds (χ2 = 7.799; p = 0.005; OR = 3.378; 95% CI, 1.410-8.092). Thus, treatment with dehydrated amnion/chorion membrane with a spongy layer improves the outcome of non-healing wounds of different aetiologies and, therefore, has to be considered early in the management of refractory wounds.

Photochemical Tissue Bonding of Amnion Allograft Membranes for Peripheral Nerve Repair: A Biomechanical Analysis.

BACKGROUND: Photochemical tissue bonding (PTB) is a technique for peripheral nerve repair in which a collagenous membrane is bonded around approximated nerve ends. Studies using PTB with cryopreserved human amnion have shown promising results in a rat sciatic nerve transection model including a more rapid and complete return of function, larger axon size, and thicker myelination than suture repair. Commercial collagen membranes, such as dehydrated amnion allograft, are readily available, offer ease of storage, and have no risk of disease transmission or tissue rejection. However, the biomechanical properties of these membranes using PTB are currently unknown in comparison to PTB of cryopreserved human amnion and suture neurorrhaphy. METHODS: Rat sciatic nerves (n = 10 per group) were transected and repaired using either suture neurorrhaphy or PTB with one of the following membranes: cryopreserved human amnion, monolayer human amnion allograft (crosslinked and noncrosslinked), trilayer human amnion/chorion allograft (crosslinked and noncrosslinked), or swine submucosa. Repaired nerves were subjected to mechanical testing. RESULTS: During ultimate stress testing, the repair groups that withstood the greatest strain increases were suture neurorrhaphy (69 ± 14%), PTB with crosslinked trilayer amnion (52 ± 10%), and PTB with cryopreserved human amnion (46 ± 20%), although the differences between these groups were not statistically significant. Neurorrhaphy repairs had a maximum load (0.98 ± 0.30 N) significantly greater than all other repair groups except for noncrosslinked trilayer amnion (0.51 ± 0.27 N). During fatigue testing, all samples repaired with suture, or PTBs with either crosslinked or noncrosslinked trilayer amnion were able to withstand strain increases of at least 50%. CONCLUSION: PTB repairs with commercial noncrosslinked amnion allograft membranes can withstand physiological strain and have comparable performance to repairs with human amnion, which has demonstrated efficacy in vivo. These results indicate the need for further testing of these membranes using in vivo animal model repairs.

Amniotic membrane transplantation: structural and biological properties, tissue preparation, application and clinical indications.

The amniotic membrane is a single epithelial layer of the placenta. It has anti-inflammatory, anti-scarring, anti-angiogenic and possibly bactericidal properties. The basement membrane of the amniotic membrane acts as a substrate to encourage healing and re-epithelialisation. It has been used in many ocular surface diseases including persistent epithelial defects (corneal or conjunctival), chemical or thermal burns, limbal stem cell deficiency, cicatrising conjunctivitis, ocular graft versus host disease, microbial keratitis, corneal perforation, bullous keratopathy, dry eye disease, corneal haze following refractive surgery and cross-linking, band keratopathy, ocular surface neoplasia, pterygium surgery, and ligneous conjunctivitis. This review provides an up-to-date overview of amniotic membrane transplantation including the structural and biological properties, preparation and application, clinical indications, and commercially available products.

Outcomes and success of amniotic membrane transplantation for the treatment of corneal diseases.

PURPOSE: The amniotic membrane (AM), the inner layer of the placenta, is a semitransparent, avascular, and thin tissue that is useful due to its structure. Amniotic membrane transplantation (AMT) avoids the need for keratoplasty to prevent corneal perforating. The purpose of the study was to evaluate the visual (gain of or no change in visual acuity) and corneal outcomes (closure of the ulcer or corneal healing) of AMT in patients with ocular surface diseases. MATERIALS AND METHODS: This was a retrospective case control study (success or failure of the surgery). It was undertaken at a single academic center. The study cohort consisted of subjects with ocular surface diseases. Patients were treated with AMT for refractory ocular surface diseases. They were divided into five subgroups according to the preoperative diagnosis. The technique of AMT used was the onlay method with two layers of AM. Primary outcome measures included best corrected visual acuity (BCVA), the number of AMTs, and reepithelization of the corneal epithelium at the end of the treatment. Two weeks to six months were given to consider epithelial closure. Treatment success was defined as corneal healing within 6 months. RESULTS: A total of the 66 eyes of 66 patients (39 male/27 female) with a mean age of 44 ± 23 years (range 1-88 years) were included in the study. A single AMT procedure achieved epithelial closure in 74.2% (n = 49) of the eyes (53% in <15 days, 19.6% in 15-30 days, and 1.5% in 1-6 months). The fastest reepithelization occurred in neurotrophic keratopathy, 76.9% of which cases occurred within 15 days after the AMT procedure. Treatment failure was observed in five patients (7.5%), four with keratitis and one with neurotrophic keratopathy. The highest closure rates were found in persistent epithelial defects, graft-versus-host disease (GvHD), and bullous keratopathy, although there was no statistically significant difference in BCVA. Pairwise comparisons were made of neurotropic keratoplasty versus bullous keratopathy (P = 0.025), neurotrophic keratopathy versus keratitis (P = 0.004), GVHD versus keratitis (P = 0.003), and lastly, GvHD versus bullous keratopathy (P = 0.023). CONCLUSIONS: AMT is a safe, valuable, and fast treatment technique to treat corneal epithelial defects stemming from different etiologies that are refractory to conventional treatment.

Unique Usages of Dehydrated Human Amnion Chorion Membrane Allografts in Dermatology.

Dehydrated human amnion chorion membrane (dHACM) allografts are synthetic skin substitutes derived from placental tissue. dHACM allografts are used for replacing lost or damaged dermal tissue, as they contain many of the components found within the extracellular matrix that are beneficial in wound healing. Common uses of dHACM allografts include the healing of diabetic and non-diabetic foot and leg ulcers, decubitus ulcers, and wounds following debridement. While these grafts have been proven to be beneficial in other disciplines of medicine, their potential for use in the field of dermatology is emerging. Current clinical cases and research have shown dHACM allografts to be beneficial in repairing damaged tissue due to dermatologic conditions. They could play a role in the treatment of conditions causing chronic wounds, including dermal scarring or loss, and the repair of fragile skin. Examples of dHACM allograft use in dermatology include cases of pyoderma gangrenosum, Netherton syndrome, and wound healing with Mohs micrographic surgery. This literature review explores the efficacy of using dHACM allografts for the treatment of healing wounds within the field of dermatology. J Drugs Dermatol. 2023;22(12):1228-1231. doi:10.36849/JDD.7115.

[Chinese expert consensus on the application of amniotic membrane in the treatment of corneal and ocular surface diseases (2023)].

Amniotic membrane (AM) can promote epithelialization, inhibit inflammation and be antimicrobial. It has been widely used in the clinical treatment of corneal epithelial and stromal defects. However, the misuse and abuse of AM might aggravate the primary disease and even lead to the loss of the best timing for other surgical interventions. Based on domestic and foreign clinical practice guidelines and medical evidence, the Cornea Group of Ophthalmology Branch of Chinese Medical Association has formed consensus opinions about the indications, surgical techniques and perioperative management of AM transplantation, so as to standardize the application of AM in the treatment of corneal and ocular surface diseases.

Corneal Descemetocele Management with Multi-Layer Amniotic Membrane Transplantation in an Ocular Graft-versus-Host Disease Case.

Background: Chronic ocular graft-versus-host disease (oGVHD) is a common ocular complication following allogeneic hematopoietic stem cell transplantation (allo-HSCT), characterized by progressive inflammation of the ocular surface and refractory dry eye. In severe cases, sterile corneal perforation can occur, which poses a significant challenge, due to the low survival rate of grafts after corneal transplantation. Case Presentation: A 47-year-old female presented to our hospital with persistent dryness, foreign body sensation, and blurred vision in her left eye. Diagnosis of graft-versus-host disease with corneal descemetocele in the left eye was made after detailed history review and thorough examination. Multi-layer amniotic membrane transplantation was performed in the affected eye, resulting in amelioration of the patient's symptoms. This amelioration of symptoms provided the patient with a level of comfort that permitted additional time while awaiting corneal transplantation. Conclusions: We report a successful case of multi-layer amniotic membrane transplantation for the management of corneal descemetocele following allo-HSCT.

Dehydrated human amnion/chorion membrane use in emergent craniectomies shows minimal dural adhesions.

Decompressive craniectomies (DCs) are routinely performed neurosurgical procedures to emergently treat increased intracranial pressure secondary to multiple aetiologies, such as subdural haematoma, epidural haematoma, or malignant oedema in the setting of acute infarction. The DC procedure typically induces epidural fibrosis post-cranial resection, resulting in adherence of the dura to both the brain internally and skin flap externally. This becomes especially problematic in the setting of skull flap replacement for cranioplasty as adherences can lead to bridging vein tear, damage to the underlying brain cortex, and other postoperative complications. Dural adjuvants, which can contribute to decreased rate of adherence formation, can thereby reduce both postoperative cranioplasty complications and operative duration. Dehydrated human amnion/chorion membrane (DHACM) allografts (AMNIOFIX, MIMEDX Group Inc., US) have been shown to reduce the rate of dural scar tissue formation in re-exploration of posterior lumbar interbody fusion operations which require entry into the epidural space. The purpose of this study was to evaluate whether or not the use of DHACM in the setting of emergent craniectomies decreased the rate of dural adhesion formation and subsequent cranioplasty complications. Patients (n=7) who underwent emergent craniectomy and intraoperative placement of DHACM were evaluated during replacement of either an autologous skull cap or a custom-made implant, at which point the degree of adhesions was qualitatively assessed. Placement of DHACM below and on top of the dura resulted in negligible adhesion being found during the defect exposure, and there were no intraoperative complications during cranioplasties. Reported estimated blood loss across the seven patients averaged 64.2ml, total operative time averaged 79.2 minutes, and time dedicated to exposing defect for bone flap placement was <3 minutes.

Clinical Outcome of Amniotic Membrane Transplant in Ocular Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis at a Major Burn Unit.

PURPOSE: To analyze the clinical outcome of amniotic membrane transplantation in patients with ocular Stevens-Johnson syndrome/toxic epidermal necrolysis at a major burn unit. DESIGN: Retrospective, non-randomized interventional study. METHODS: A retrospective chart review from April 2014 to January 2022 of 43 patients (85 eyes) at a burn center who underwent amniotic membrane transplantation (AMT) for severe ocular Stevens-Johnson Syndrome (SJS), toxic epidermal necrolysis (TEN), or SJS/TEN was performed. Data regarding the clinical course and outcome were obtained. A comparison between the use of cryopreserved AMT rings (cryoAMT) and dehydrated AMT (deAMT) was also assessed. RESULTS: A total of 85 eyes in 43 patients underwent AMT for severe ocular SJS/TEN. Of the eyes, 72 received deAMT with symblepharon ring, whereas 13 received cryoAMT over the cornea surface. All patients had deAMT placed over the eyelid margins and palpebral conjunctivae and tucked into the fornices. The average best-corrected visual acuity (BCVA) on last follow-up examination was 20/33, 20/30, and 20/34 in all eyes, the cryoAMT group, and the deAMT group, respectively (no significant difference between groups). The most common suspected inciting agent was lamotrigine (17% of all cases). The average long-term complication score was 1.4, with no significant difference between the cryoAMT group (1.6) and the deAMT group (1.4, P = .5). Symblepharon formation was seen more in the cryoAMT group compared to the deAMT group (P < .05). CONCLUSION: The use of AMTs in severe ocular SJS/TEN greatly mitigates long-term complications and improves visual outcome. The retrospective nature of this study limits substantial conclusions regarding any significant difference in outcome between AMT treatment methods. Nevertheless, the use of cryopreserved AMT rings has a similar outcome profile compared to use of dehydrated AMTs with symblepharon ring. Further research is needed to evaluate optimal AMT techniques.