Alloplastic Nasal and Perialar Augmentation

Current Practices in Dorsal Augmentation Rhinoplasty

BACKGROUND

Dorsal augmentation rhinoplasty addresses the aesthetic and functional impairments caused by a deficient nasal dorsum. Augmentation rhinoplasty can be performed using a variety of different surgical techniques and grafting materials that all have distinct advantages and disadvantages.

METHODS

Grafting materials have unique characteristics, uses, and safety profiles. A detailed overview of various grafting materials and their uses, risks, and benefits is provided.

RESULTS

Autologous grafting materials include septal cartilage, auricular cartilage, and costal cartilage. These donor sites can provide various amounts of en bloc or diced cartilage. Alternatively, bone may be used when strong structural stability is required, and soft tissue may be used to fill mild to moderate defects. Homologous grafts (e.g., irradiated and nonirradiated rib) and acellular dermal matrices are alternatives to autologous graft with many similar advantages and no need for an additional surgical site. Lastly, alloplastic implants may be successfully used for dorsal augmentation if both patient and surgeon understand their associated risks.

CONCLUSION

To perform successful dorsal augmentation, surgeons should be familiar with the wide variety of operative approaches and augmentation materials that are currently available and understand their risks, benefits, and uses.

Dorsal Augmentation

To manage the deficient nasal dorsum, a thorough knowledge of dorsal augmentation techniques should be mastered by the rhinoplasty specialist. Indications for dorsal augmentation may arise in both primary and revision rhinoplasty presentations. To direct operative planning, a complete facial analysis, noting the importance of maintaining overall nasofacial balance, is essential. An array of techniques, including autologous and nonautologous (ie, allogeneic and synthetic) sources, have been used globally-each carrying its own advantages and disadvantages. The authors believe autologous grafts to be the optimal source for dorsal augmentation because of their biocompatibility and ability to produce natural and long-lasting outcomes.

Nose and Midface Augmentation by Rib Cartilage Grafts: Methods and Outcome in 32 Cases

Recession of the midface is a relatively common condition that can have a negative impact on facial and nasal aesthetic appearance, and it poses a challenge to plastic surgeons. In cases with generalized maxillary retrusion and/or malocclusion, bone advancement surgery is required, but in localized cases, mostly seen in cleft lip patients, the quest is for an ideal material and a proper technique that would be used to augment the receding area. Throughout a period of seven years, thirty-two patients with nose and midface retrusion were managed by a construct of rib cartilage grafts designed to compensate the deficiency at the maxillary, piriform, and premaxillary areas. Results were satisfactory for most patients in terms of improved fullness of malar area, improved nasal tip projection and rotation, and improvement of upper lip. The presented technique of rib cartilage grafting is a safe and effective method for nose and midface augmentation.

Midface augmentation using bony segments obtained from sagittal splitting angle ostectomy in asians

BACKGROUND

Asians characteristically have flat or broad and round facial features. These characteristics are primarily attributable to enlarged and widened jawbones, impressive muscles associated with mastication, and a zygomatic arch involving the masseter. Their faces appear flat, with midface regression in the center. This regression is often combined with a narrow nasolabial angle and a depressed alar base and cheeks.

METHODS

Between June of 1999 and March of 2002, 32 patients underwent facial contouring surgery for prominent mandible angles and subsequent rhinoplasty. After bilateral prominent mandible angle modification, midface augmentation was accomplished using bony segments obtained from sagittal splitting angle ostectomy. The bony fragments were inserted via an intraoral approach into the paranasal area, trimmed, and then reshaped with an osteotome.

RESULTS

Of these 32 patients (31 women and one man), 47 percent were in their thirties. The amount of reduction of the distance between mandible angles on the frontal view, the extent of protrusion of the paranasal area on the profile view, and the degree of patient satisfaction were the primary areas of postoperative evaluation. Complications included one wound infection and two cases of wound dehiscence. All but two patients were satisfied with their results.

CONCLUSIONS

Satisfactory aesthetic results were obtained with a one-stage modification of the mandible angles and advancement of the midfacial area. The advantages included the absence of any additional costs and a low infection rate. None of the disadvantages of an autologous transplant were present, and the procedure yielded aesthetically superior results. The authors advocate this method.

Augmentation of the nasal dorsum with autogenous costal cartilage using the "edge-on" technique

Carved costal cartilage autografts are commonly used for nasal augmentation in saddle nose deformities. One major disadvantage of these carved grafts is postoperative warping. To prevent warping of costal cartilages, we used the "edge-on" technique. The inferior border of the cartilage is rotated 90 degrees to become the convex dorsum. No cartilage is trimmed or carved, and hence the intrinsic stress forces within the graft are not disturbed. The results in 21 patients are documented with long-term follow up (mean, 4 years) and showed no evidence of warping. Other complications, advantages, and disadvantages of the technique are discussed.

Combined use of hair and fibrin glue for soft tissue augmentation: experimental study

A vast variety of alloplastic materials together with autogenous grafts have been used for the correction of contour deformities related to aesthetic and reconstructive purposes. Despite a number of well-tolerated materials, the ideal has not yet been reached, although well-tolerated autogenous grafts have higher rates of resorption and distortion. The limited volume of autogenous grafts and concerns about donor-site morbidity may obligate the surgeon to use implantation materials. Covering almost every property of an ideal implantation material, hair, an organic autogenous nonvital tissue, was used for soft tissue augmentation in this experimental study. Hair pellets of 10 New Zealand rabbits were prepared and shaped as 1 x 1 x 1-cm cubes with the help of fibrin sealant, then inserted subcutaneously. The materials were evaluated 4 months later. No complications such as infection or extrusion were seen. The materials were intact, with no signs of resorption, but the shapes were distorted due to the pressure of the surrounding tissues. Histopathologic findings also demonstrated that the hair was well tolerated by the adjacent tissues. Different processes may enable hair to be used as a filler material in clinical practice. Well-tolerated, nonresorbable injectable materials or shaped implants may be obtained at low cost using hair.

Rhinoplasty model in rabbit

BACKGROUND

Rhinoplasty has become one of the most frequently requested and performed surgical procedures for both functional and aesthetic purposes. As an attention-attracting prominence, even the slightest disfigurement of the nose causes serious disturbance to the patient before or after the operation. Functional problems also cause discomfort. For these reasons, postrhinoplasty complications are regarded as challenging problems for both for the patient and the surgeon. Some cases necessitate grafts for better aesthetic or functional outcome, but there is still controversy over the preference for autogenous or allogenous grafts, both for primary and secondary cases. Evaluation of autogenous and allogenous grafts implanted in the nose is quite challenging for several reasons, including the possibility of unpredictable complications leading to catastrophic disfigurements, the impossibility of obtaining pathologic specimens, and the need for a long follow-up period for stable results. An experimental model for rhinoplasty, fulfilling the need for precise evaluation, was planned and performed after anatomical observation of the noses of rabbits.

METHODS

Fifteen adult New Zealand rabbits were used, five for the anatomical evaluation and 10 for the rhinoplasty model. Computed tomographic images and measurements were obtained before and after the surgical processes.

RESULTS AND CONCLUSION

This experimental model for rhinoplasty has not been reported in any previous studies. This study demonstrates the surgical anatomy of the rabbit in detail and constitutes a guide for researchers as a convenient experimental model for rhinoplasty, with all stages similar to those performed on humans.

Mersiline mesh in premaxillary augmentation

Premaxillary retrusion may distort the aesthetic appearance of the columella, lip, and nasal tip. This defect is characteristically seen in, but not limited to, patients with cleft lip nasal deformity. This study investigated 60 patients presenting with premaxillary deficiencies in which Mersiline mesh was used to augment the premaxilla. All the cases had surgery using the external rhinoplasty technique. Two methods of augmentation with Mersiline mesh were used: the Mersiline roll technique, for the cases with central symmetric deficiencies, and the Mersiline packing technique, for the cases with asymmetric deficiencies. Premaxillary augmentation with Mersiline mesh proved to be simple technically, easy to perform, and not associated with any complications. Periodic follow-up evaluation for a mean period of 32 months (range, 12-98 months) showed that an adequate degree of premaxillary augmentation was maintained with no clinically detectable resorption of the mesh implant.

Biomaterials in craniofacial reconstruction

Biomaterials have become an integral component of craniofacial reconstruction. Their increasing ease of use, long "shelf-life," and safety enables them to be used effectively and play an important role in reducing operating times. There are various biomaterials currently available and specific usages have been characterized well in the literature. This article reviews different biomaterials that can be used in craniofacial reconstruction,including autogenous bone, methyl methacrylate and hard tissue replacement,hydroxyapatite, porous polyethylene, bioactive glass, and demineralized bone.

Advances in Craniosynostosis Research and Management

The purpose of the present paper is to analyze the most recent advances in the field of craniosynostosis basic and clinical research and management, and to give an overview of the more frequently adopted surgical strategies. After reviewing some basic concepts regarding normal craniofacial embryology and growth, aetiopathogenesis of craniosynostosis and craniofacial dysostosis, classification and diagnosis and historical evolution of surgical treatment, the authors elaborate on a selection of topics that have modified our current understanding of and therapeutical approach to these disease processes. Areas covered include advances in molecular biology and genetics, imaging techniques and surgical planning, resorbable fixation technology, bone substitutes and tissue engineering, distraction osteogenesis and the spring-mediated cranioplasties, resorbable distractor devices, minimally invasive surgery and in utero surgery. A review of the main subtypes of craniosynostosis and craniofacial dysostosis is presented, including their specific clinical features and a commentary on the presently available surgical options.

Assessment of the effects on growth of porous hydroxyapatite granule cranioplasty in the immature guinea pig craniofacial skeleton

The immature guinea pig was used to study the effects on growth of porous granular hydroxyapatite used as an onlay cranioplasty and inlay cranioplasty to reconstruct full-thickness cranial defects in a growing craniofacial skeleton. Forty Hartley guinea pigs, 20 immature animals and 20 mature animals, were divided into four groups each containing five mature and five immature animals. The mature animals served as controls. Group I underwent elevation and replacement of the parietal periosteum. Group II underwent placement of hydroxyapatite between periosteum and parietal bone. Group III underwent elevation and replacement of autogenous bone flap after the formation of a 1 x 1-cm craniectomy defect in the parietal skull. Group IV underwent elevation of a 1 x 1-cm parietal craniectomy and reconstruction of the defect with hydroxyapatite granules placed between the dura and periosteum. Immature animals were killed at maturity at 3.5 months and mature animals were killed 2.5 months postoperatively. Macroscopic examination of the operative field, transverse and longitudinal cephalometric measurements, and histological sections encompassing the operative sites were compared. Macroscopically, all reconstructed operative sites were fully incorporated into the cranium. Histological staining of the sectioned operative site revealed no hydroxyapatite migration through the cranial bone or dura. No inflammatory or foreign body reaction was evident in the subcutaneous tissue, periosteum, or dura. No statistically significant cephalometric intergroup or intragroup differences were found at the conclusion of the study. The results of this study indicate that a granular porous form of hydroxyapatite may be used as an onlay or inlay cranioplasty in the immature guinea pig craniofacial skeleton without evidence of dural inflammation, granule migration, or growth restriction or retardation.

Maxillary reconstruction: functional and aesthetic considerations

Maxillary reconstruction is a challenging endeavor in functional and aesthetic restoration. Given its central location in the midface and its contributions to the key midfacial elements--the orbits, the zygomaticomaxillary complex, the nasal unit, and the stomatognathic complex--the maxilla functions as the keystone of the midface and unifies these elements into a functional and aesthetic unit. Maxillary defects are inherently complex because they generally involve more than one midfacial component. In addition, most maxillary defects are composite in nature, and they often require skin coverage, bony support, and mucosal lining for reconstruction. In the reconstruction of maxillary defects secondary to trauma, ablative tumor surgery, or congenital deformities, the following goals must be met: (1) obliteration of the defect; (2) restoration of essential functions of the midface, such as mastication and speech; (3) provision for adequate structural support to each of the midfacial units; and (4) aesthetic reconstruction of the external features. This review will discuss the pertinent anatomic considerations, the historical approaches to maxillary reconstruction, and the merits of the techniques in use today, with an emphasis on state-of-the-art reconstruction and dental rehabilitation of extensive maxillary defects.