Autologous bone grafting with adjunctive use of acellular dermal matrix for alveolar cleft defects: early outcomes

Influence of a resorbable collagen membrane for alveolar bone graft on clinical outcomes and ridge volume stability in cleft alveolus

This study compared the clinical outcomes, graft quality, and graft quantity after alveolar bone grafting with and without a resorbable collagen membrane. Twenty unilateral cleft patients undergoing defect repair with cancellous iliac bone were assigned to either the collagen membrane group (Mb group) or standard group without a membrane (St group). Postoperative pain and swelling, bone density, and bone volume and quality were assessed. The Mb group showed significantly lower postoperative pain than the St group (P < 0.001) and significantly less swelling (P < 0.01) on day 3 postoperative. The reduction in bone density was significantly greater in the St group than in the Mb group at 1 and 3 months postoperative (P ≤ 0.001), but not at 6 months. The reduction in bone volume in the St group was significantly greater than that in the Mb group at 3 months (29.11 ± 6.26% vs 17.67 ± 11.89%, P = 0.016) and 6 months postoperative (40.95 ± 6.81% vs 25.67 ± 11.51%, P = 0.002). Nine cases in the Mb group versus six in the St group showed good bone quality. In conclusion, the collagen membrane facilitated predictable clinical outcomes in bone maturation, bone volume preservation, and bone bridging in the alveolar bone graft.

Clinical applications of acellular dermal matrices: A review

INTRODUCTION

The extracellular matrix (ECM) plays an integral role in wound healing. It provides both structure and growth factors that allow for the organised cell proliferation. Large or complex tissue defects may compromise host ECM, creating an environment that is unfavourable for the recovery of anatomical function and appearance. Acellular dermal matrices (ADMs) have been developed from a variety of sources, including human (HADM), porcine (PADM) and bovine (BADM), with multiple different processing protocols. The objective of this report is to provide an overview of current literature assessing the clinical utility of ADMs across a broad spectrum of applications.

METHODS

PubMed, MEDLINE, EMBASE, Scopus, Cochrane and Web of Science were searched using keywords 'acellular dermal matrix', 'acellular dermal matrices' and brand names for commercially available ADMs. Our search was limited to English language articles published from 1999 to 2020 and focused on clinical data.

RESULTS

A total of 2443 records underwent screening. After removing non-clinical studies and correspondence, 222 were assessed for eligibility. Of these, 170 were included in our synthesis of the literature. While the earliest ADMs were used in severe burn injuries, usage has expanded to a number of surgical subspecialties and procedures, including orthopaedic surgery (e.g. tendon and ligament reconstructions), otolaryngology, oral surgery (e.g. treating gingival recession), abdominal wall surgery (e.g. hernia repair), plastic surgery (e.g. breast reconstruction and penile augmentation), and chronic wounds (e.g. diabetic ulcers).

CONCLUSION

Our understanding of ADM's clinical utility continues to evolve. More research is needed to determine which ADM has the best outcomes for each clinical scenario.

LAY SUMMARY

Large or complex wounds present unique reconstructive and healing challenges. In normal healing, the extracellular matrix (ECM) provides both structural and growth factors that allow tissue to regenerate in an organised fashion to close the wound. In difficult or large soft-tissue defects, however, the ECM is often compromised. Acellular dermal matrix (ADM) products have been developed to mimic the benefits of host ECM, allowing for improved outcomes in a variety of clinical scenarios. This review summarises the current clinical evidence regarding commercially available ADMs in a wide variety of clinical contexts.

Cleft Alveolar Bone Graft Materials: Literature Review

INTRODUCTION

Since the early stages of alveolar bone grafting development, multiple types of materials have been used. Iliac cancellous bone graft (ICBG) remains the gold standard.

DESIGN/METHODS

A review of literature is conducted in order to describe the different bone filling possibilities, autologous or not, and to assess their effectiveness compared to ICBG. This review focused on studies reporting volumetric assessment of the alveolar cleft graft result (by computed tomography scan or cone beam computed tomography).

RESULTS

Grafting materials fall into 3 types: autologous bone grafts, ICBG supplementary material, and bone substitutes. Among autologous materials, no study showed the superiority of any other bone origin over iliac cancellous bone. Yet ICBG gives inconsistent results and presents donor site morbidity. Concerning supplementary material, only 3 studies could show a benefit of adding platelet-rich fibrin (1 study) or platelet-rich plasma (2 studies) to ICBG, which remains controversial in most studies. There is a lack of 3-dimensional (3D) assessment in most articles concerning the use of scaffolds. Only one study showed graft improvement when adding acellular dermal matrix to ICBG. Looking at bone substitutes highlights failures among bioceramics alone, side-effects with bone morphogenetic protein-2 composite materials, and difficulties in cell therapy setup. Studies assessing cell therapy-based substitutes show comparable efficacy with ICBG but remain too few.

CONCLUSION

This review highlights the lack of 3D assessments in the alveolar bone graft materials field. Nothing dethroned ICBG from its position as the gold standard treatment at this time.

Management of Oronasal Fistulas in Patients With Cleft Lip and Palate

BACKGROUND

The oronasal fistula in cleft patients is one of the complications that can be found after primary surgeries due to a failure of healing of the surgical repair that causes the communication between the oral and nasal cavities. A number of procedures can be implemented to correct the fistula and it is not clear if a particular technique is the best to be recommended.

OBJECTIVE

This study aims to systematically analyze the scientific evidence regarding the treatment of oronasal fistulas located in the lingual-alveolar and labial-alveolar regions in patients with cleft lip and palate who have undergone primary surgeries.

MATERIAL AND METHODS

A bibliographic search of articles published until September 2018 without restricted year and language of publication, in PubMed (Medline), Scopus, Cochrane, Web of science, and BVS databases. The MeSHterms "Fistula," "Oral Fistula," and "Cleft Lip" were used, which were related to each other and with other keywords related to the subject of the review through the "OR" and "AND" operators. The quality of the publications was evaluated according to the guidelines of the Methodological Index for Nonrandomized Studies.

RESULTS

After applying the eligibility criteria, a total of 18 articles were selected for the extraction of data and qualitative analysis.

CONCLUSION

All publications analyzed in this review reported the fistula treatment at the same surgical time as the bone graft, independently of the donor area, the type of cleft treated and the patient's age at operation. There was no consensus among the studies on the best treatment type for oronasal fistulas located in the alveolar region, and further comparative studies between the existing techniques will be necessary to address this question.

Functional stability analyses of maxillofacial skeleton bearing cleft deformities

The symmetrically stable craniofacial bony structure supports the complex functions and delicate contour of the face. Congenital craniofacial deformities are often accompanied by bony defects and have been repetitively correlated with compromised dento-maxillary stability, but neither the extent nor the pattern of cleft-related maxillary instability has been explored in detail. Furthermore, it is largely unknown if the bony defect and related instability are correlated with secondary maxillary deformity common among patients with orofacial clefts. With the aid of finite element modeling, we studied the detailed relationship between cleft-related bony defect and maxillary stability under occlusal loading. Craniofacial models were generated based on cone-beam computed tomography data and loaded with mimicked bite forces along the axial axis of each tooth. Our data showed that all cleft models exhibited more asymmetrical deformations under mastication compared with the normal. Models with palatal cleft demonstrated greater asymmetry, greater dental arch contraction, and less maxillary protrusion compared to models with alveolar cleft only. For unilateral cleft models, alveolus on non-cleft side tended to be more protruded and lifted than the cleft side. For bilateral cleft models, the most prominent feature was the seriously contracted alveolar arch and curved and pitched premaxillae. These findings indicated cleft type-specific pattern of maxillary instability, which were largely in accordance with dentoalveolar morphological features among patients. Collectively, our study elucidated the detailed relationship between cleft bony defect and the pattern of maxillary instability, and suggested a prototype for studying the abnormal maxillary and dental arch growth among patients with craniofacial deformities.

Use of Acellular Dermal Matrix in Craniosynostosis

In craniofacial surgery, a wide spectrum of pathological conditions are usually treated. The aetiology of these could be congenital, traumatic, infective, post-tumor resection, postradiation, autoimmune, iatrogenic, or other miscellaneous conditions. The surgical approach for the procedures is usually via a coronal incision. In a large proportion of the patients, the frontal bone is removed to obtain intracranial access. The frontal bone is then replaced either in its original form or in a remodeled state. In congenital conditions the supraorbital bar and frontal bone is often also removed, remodeled, and replaced. One of the common late sequelae following craniofacial surgery is contour irregularities of the frontal region. These irregularities can vary in their extent. They are invariably palpable and often visible. Surgeons have attempted various methods to improve the contour irregularities. Despite these measures contour irregularities can still ensue. In the authors' unit, the authors have been using acellular dermal matrix in an attempt to diminish the contour irregularities in the frontal region following craniofacial reconstruction for craniosynostosis. This has been used in 35 patients undergoing craniosynostosis correction. Of the 35 patients, 12 were for plagiocephaly, 7 for brachycephaly, 10 for scaphocephaly, 4 for trigonocephaly, and 2 for combined coronal and metopic synostosis. The age of the patients ranged from 5 months to 12 years (mean 20.5 months). There were 21 males and 14 females. The follow-up ranged from 10 to 48 months (mean 23 months).

[Application of team approach and key techniques of cleft lip and palate]

The development of an expert consensus based on specific domestic situations will provide practical guidance to the efforts aiming at improving cleft care in China. The team approach of twenty-one cleft centers were pooled together, covering pre-surgical orthopedics, primary surgical repair, orthodontic treatment, alveolar bone graft, secondary deformity correction, palatal fistulae repair, the diagnosis and treatment of velopharyngeal incompetence, speech therapy, otitis media management, and skeletal deformity correction. Agreement was achieved among the authors concerning the application of critical surgical and non-surgical techniques. The ambition of this consensus is to introduce more clinicians to the revolution of sequential treatment of clefts, and form the basis for a more comprehensive cleft care manual in the future.

Osteogenesis effect of guided bone regeneration combined with alveolar cleft grafting: assessment by cone beam computed tomography

Cone beam computed tomography (CBCT) allows for a significantly lower radiation dose than conventional computed tomography (CT) scans and provides accurate images of the alveolar cleft area. The osteogenic effect of guided bone regeneration (GBR) vs. conventional alveolar bone grafting alone for alveolar cleft defects was evaluated in this study. Sixty alveolar cleft patients were divided randomly into two groups. One group underwent GBR using acellular dermal matrix film combined with alveolar bone grafting using iliac crest bone grafts (GBR group), while the other group underwent alveolar bone grafting only (non-GBR group). CBCT images were obtained at 1 week and at 3 months following the procedure. Using Simplant 11.04 software, the bone resorption rate was calculated and compared between the two groups. The bone resorption rate from 1 week to 3 months following bone grafting without the GBR technique was 36.50±5.04%, whereas the bone resorption rate using the GBR technique was 31.69±5.50% (P=0.017). The application of autogenous iliac bone combined with the GBR technique for alveolar bone grafting of alveolar cleft patients can reduce bone resorption and result in better osteogenesis.

The last resort for reconstruction of nasal floor in difficult-to-repair alveolar cleft cases: a retrospective study

AIM

This article describes four new methods as the last resort for reconstruction of the nasal floor in difficult-to-repair alveolar cleft patients, including bone suture technique, vascularized interpositional periosteal-connective tissue flap from the palate (VIP-CT flap), anteriorly based inferior turbinate flap, and skinless subcutaneous nasolabial flap, with emphasis on indications and limitations.

METHODS

In a retrospective study, data were obtained from 214 patients referred to the Department of Oral and Maxillofacial Surgery, Mashhad Dental School, Iran, for alveolar cleft bone grafting in 2004-2013. Eighteen patients had been treated using special techniques other than direct suturing for reconstruction of the nasal floor during alveolar cleft bone grafting.

RESULTS

Eighteen patients had been treated using these techniques as the last resort for nasal floor reconstruction; including bone suture technique (50%), inferior turbinate flap (33.3%), VIP-CT flap (11.2%) and nasolabial flap (5.5%). All the patients had a unilateral alveolar cleft, 72.2% of which were located on the left side and 44.5% of the patients were female.

CONCLUSION

Nasal floor reconstruction in 8.4% of alveolar cleft patients needed special techniques and flaps.

The Microvascular Corticocancellous Femur Flap for Reconstruction of the Anterior Maxilla in Adult Cleft Lip, Palate, and Alveolus Patients

Objective

Free nonvascularized alveolar bone grafting in severe defects of the cleft region often results in poor implant bed conditions. Here an alternative augmentation technique using a new technique of vascularized bone transfer is described.

Design

In five patients with clefts of the lip, palate, and alveolus (four unilateral, one bilateral) there was a severe defect of the anterior maxillary alveolar ridge after tooth loss. The patients previously had augmentative surgery one to three times without success. The defect was covered using a microvascular corticocancellous transplant from the medial distal femur. The defects to be corrected measured 2.5 to 4.0 cm long, 1.0 to 1.5 cm wide, and 1 to 1.5 cm high. The microvascular pedicle of the femur bone flap was 3 to 7 cm long. The descending genicular artery was anastomosed to the facial or labial superior artery and the accompanying veins accordingly. In every case, the anastomoses were performed via an intraoral transmucosal approach.

Results

There were no serious complications and no flap loss. In all patients the defect was covered by a flap of the correct size and design. All patients were treated with dental implants (13 total) 6 months after successful reconstruction of the ridge. The implants were loaded 4 to 6 months after placement with fixed superstructures. There were good peri-implant conditions and no implant loss.

Conclusion

The microvascular osteoperiosteal femur flap can be used successfully in individual reconstruction of segmental defects of the alveolar ridge in adult cleft patients.

Acellular dermal matrix in palatoplasty

The primary goal of palatoplasty is to allow normal speech through the correction of velopharyngeal incompetence. Failure to accomplish a tension-free, watertight closure predisposes the palatoplasty patient to postoperative fistula formation. Fistulas may in turn contribute to velopharyngeal incompetence. Reported fistula rates vary widely, ranging from 0% to greater than 70%; recurrence rates after attempted repair approach 65% in some series. These lesions therefore represent a significant clinical burden. Acellular dermal matrix materials have been introduced into various phases of palatoplasty as a strategy to augment repairs and minimize postoperative fistula formation, as well as repair fistulas when they do occur. In this article, the authors review the existing literature regarding acellular dermal matrix in palatoplasty and describe their own algorithm and results for primary and secondary palatoplasty in which acellular dermal matrix plays a central role.

Acellular dermal matrix: general principles for the plastic surgeon

Acellular dermal matrix (ADM) is a recently-developed, biologically-derived product with many useful applications in plastic surgery, in both cosmetic and reconstructive procedures. While the use of ADM initially outpaced quality literature, within the past 10 years the literature on ADM has rapidly expanded. Some of these data show promising results in treating historically-challenging problems within our field; thus, an effort to clarify and summarize existing work with ADM is indicated. While subsequent articles in this supplement focus on specific applications, this article provides a general overview of the biology of, applications for, and existing literature on ADM.