Until recently, functional units for the reconstructive options of jaw and face have been considered according to defect site, such as the tongue, floor of the mouth (FOM), buccal cheek, mandible, anterior maxilla, posterior maxilla and/or palate, orbital wall with/without eyeball exenteration, and scalp and/or calvarial defects. In addition, the oral cavity consists of the lips, buccal mucosa, mandibular and maxillary alveolar ridges, retromolar trigone (RMT), hard palate, FOM, and tongue. The main structures in the oral pharynx are the base of the tongue, tonsillar fossae, lateral and posterior pharyngeal walls, and soft palate.(Fig. 1) Many reconstructive surgeons have relied on the reconstructive ladder or elevator concept, which proceeds from the least to most complex options. The reconstructive concepts of these functional units of the jaw and face are variable and can be very complex. In addition, there is no validated or scientifically proven basis for deciding which flap to use for reconstruction, so decisions are often made based on the direct and indirect experiential knowledge of the reconstructive surgeon. Reconstructive options for glossectomy, FOM, or buccal cheek defects include direct closure followed by additional skin graft, radial forearm free (RFF) flap, dorsalis pedis artery (DPA) flap, anterolateral thigh (ALT) flap, and lateral upper arm flap (LUAF). After mandibulotomy and/or mandibulectomy, hard tissue reconstruction with titanium mesh with autogenous bone chips, rib bone graft with/without serratus anterior muscle (SA) flap, fibula free flap (FFF), and deep circumflex iliac artery free flap have been considered.
Maxillofacial obturators have been considered for functional recovery, especially in the midface and maxilla, from main defects such as alveolotomy or partial or total maxillectomy. Repair of most midface defects has focused on the oral mucosal lining first, followed by secondary bone reconstruction with the fibula, orbital rim preservation, etc. For extensive mandibulectomy with/without maxillectomy, latissimus dorsi (LD) free flap, pectoralis major muscle flap (PMMF) with reconstruction plate (R-plate)1, rectus abdominis myocutaneous (RAM) free flap with R-plate, and double flaps with perforators may be considered.
Orbital defects related to malignancy in the upper maxilla, orbital contents, external auditory canal, or others include not only eyeball defects, but also defects of whole orbital structure including the surrounding bony architecture. Orbital exenteration defects involving superstructure maxillectomy with orbital exenteration or orbitomaxillectomy, may be reconstructed using a magnet-retained silicone prosthesis with an implant, which has various advantages over either adhesive or spectacle-retained prostheses2. Faced with these diverse needs and requests from patients with facial and jaw defects, mainly due to malignant diseases3-5, severe maxillofacial trauma6-8, uncontrolled head and neck infection9-11 or bite wounds from animals12, there are several limitations to reconstruct complex defects involving the eyes, nose, lips, buccal cheeks, etc. Thus, based on the modified reconstructive ladder or elevator concept, operative risk, donor site morbidity, and long-term outcomes, the simplest option that will achieve the best long-term outcomes in terms of optimal form and function with the lowest donor morbidity should be chosen. This featured article discusses current options for jaw and facial reconstruction with their limitations and offers updated guidelines in various defect situations.
This paper was structured based on Arksey and O’Malley’s review scoping methodological framework.
Step 1. Focal question
“What are the current options in jaw and facial reconstruction?”
Step 2. Identifying relevant studies
Literature searches were performed in the MEDLINE (via PubMed) database for articles published up to July 2023, using MeSH, Emtree, and DeCS/MeSH terms and other free terms combined by the Boolean operators “OR” and “AND”:
For reconstruction in a specific region, the following MeSH, Emtree, and DeCS/MeSH terms and other free terms combined by the Boolean operators “OR” and “AND” were used:
Manual direct searches were performed in the
Step 3. Study selection
Controlling keywords in the search strategy were defined to identify studies on current options in jaw and facial reconstruction. Elements of the PICO question were applied: Participant (P): human; Intervention (I): any kind of technique used for reconstruction in oral and maxillofacial surgery; Comparison (C): not applicable in this study; and Outcomes (O): reconstructed oral and maxillofacial defects.
Inclusion criteria were English literature; human species; and case report, clinical study, or clinical trial. Exclusion criteria were irrelevant studies and absence of full text.
Step 4. Charting the data
Data were collected as Excel files. We scanned the titles and evaluated the entire text. The data were categorized based on keywords.
Step 5. Collating, summarizing and reporting the results
After mapping the information obtained from the study, we present a narrative description of the results in three ways; (1) descriptive information on available techniques for oral and maxillofacial reconstructions; (2) specific reconstruction techniques for specific regions of the face and jaws; and (3) pearls and pitfalls of the techniques.
The data search resulted in 5,270 articles. Application of the inclusion and exclusion criteria resulted in the following results:
Our database: 78 articles
After removing duplicates and irrelevant studies, 159 studies were selected for the review.(Fig. 1)
Apart from maintaining the contour of the skull itself, scalp reconstruction with local flaps is planned. The standard for the size of the defect for skull reconstruction is usually 3 cm, and for defects larger than this, skull reconstruction is considered to protect the skull contents13,14. Materials such as titanium mesh or polymethyl methacrylate are representative materials for skull reconstruction. It is known as an alloplastic material, and reconstructive surgery using this alloplastic material is known to be effective, including in the scalp defect cases.
Local flaps for scalp defects are determined based on a standard of 3 cm, which is due to the limited elasticity of the scalp skin, unlike other parts of the body.(Fig. 2) Rotation-advancement flaps that contain at least one axial vessel and have a wide origin are common. If there is a shortage of flaps, skin grafting can be considered, and tissue expanders and latissimus dorsi free flaps are options that can be selected for the defect. When using a microvascular flap, the superficial temporal blood vessels can be mainly used, and the scalp incision should be made by avoiding the transplant site as much as possible. Fig. 2 shows the basic algorithm proposed for scalp reconstruction15-17.
Skull base reconstruction essentially involves separating the dura from the sinuses and oral cavity, eliminating dead space, and providing adequate volume to restore facial contour. A flap that does not have a large soft tissue volume is mainly needed, and for this purpose, the main goals are a waterproof dura seal, a barrier between the dura mater and the oral cavity, orbital support, and restoration of facial function and appearance. The skull base lesion itself is divided based on anatomical criteria, and skull base reconstruction is planned based on this. Fig. 2 shows an anatomy-based classification for skull base reconstruction. Region I includes the orbit, nose, paranasal sinuses, and the interior of the sieve plate, and may extend into the anterior cranial fossa or begin in the clivus and extend into the foramen magnum. Region II is the area from the petrosotemporal bone to the posterior orbital wall, including the lateral skull base and infratemporal fossa and pterygopalatine fossa region, and may extend into the middle cranial fossa. Region III defects are areas of tumor that arise in the ear, parotid gland, or temporal bone, which may extend to the middle or posterior cranial bone15,16.
By accurately reconstructing the orbital wall, exophthalmos, enophthalmos, or vertical dystopia can be prevented. In particular, eye muscles and surrounding fatty tissue should not be captured, and damage to the optic nerve and oculomotor nerve in the orbital region should be avoided. Temporalis muscle flaps, which are useful for reconstruction of region I and II, may have limited function due to additional postoperative resection and postoperative radiation therapy. If the facial nerve is resected, repair and rehabilitation of the facial nerve must be considered, and maxillofacial prosthetic rehabilitation may be the most appropriate method to replace the resected facial structures such as the orbits, nose, and ears, and may be used temporarily in preparation for reconstruction of other tissues. In addition, all scalp and skull base reconstruction patients must be carefully observed for various side effects that may occur after surgery, such as encephalocephaly, cerebrospinal fluid leakage, meningeal infection, and visual impairment17. Fig. 2 shows the basic suggested algorithm for skull base reconstruction.
The basic strategic algorithm for midface reconstruction involving the maxilla is shown in Fig. 3. The midface is based on a pair of maxilla, which is formed by fusing at the suture between the left and right maxillae, and the border of the midface is formed by the palate meeting the floor and side walls of the nasal cavity and the floor and inner wall of the orbit18,19. Including these maxillae, the midface is composed of the left and right zygoma, frontal and ethmoid bones, nasal cavity, lacrimal bone, inferior turbinate bone, palatine bone, and inferior base of skull. Basic considerations of maxillary reconstruction are initial treatment of obturator prosthesis delivery to recreate a partition between the oral and nasal cavities; restoration of facial contour; improvement of mastication, articulation, and speech; and reduction of drooling by providing buccal musculature and lip support20,21. Reconstructive classification of palatomaxillary defects can be categorized as superstructure maxillectomy, posterior palatomaxillectomy, hemipalatomaxillectomy, premaxillary resection, bilateral palatomaxillectomy, maxillectomy with orbital floor resection, and maxillectomy with orbital exenteration.(Fig. 4)
Reconstruction of the maxilla itself is more difficult than any other part of the face and jaw because it is essential to distinguish the three-dimensional shape between the oral mucosa and the nasal lining. Another reason for the difficulty is simultaneous hard tissue reconstruction and soft tissue reconstruction considering the maximum morphological reconstruction of the orbit and infraorbital area as well as the anatomical details of the nasal cavity and the patient’s physiologic condition. Physiological reconstruction for breathing comfort and optimal speaking ability must also be considered22-24.
Although reconstructive surgery for supramaxillectomy does not include the palatine bone or orbital bone tissue, the purpose is to prevent exposure of the skull base through buccal soft tissue reconstruction. For defects containing palatal bone tissue, a closure device using a prosthesis can be used. When the retention is insufficient, the retention of the closure device is achieved using surrounding teeth, including canines, and alveolar bone. Hemipalatomaxillectomy requires reconstruction of the palate and alveolar bone in front of the canines, and it is preferable to use an obturator or removable prosthetic device to ensure maximum retention and support rather than using a reconstructive flap. When reconstruction surgery including hard tissue becomes possible in the future, efforts are absolutely necessary to complete the entire process, including lining the existing dental prosthesis or realigning the teeth through alveolar bone grafting.
Although this prosthetic rehabilitation can achieve satisfactory results in most cases, several complications such as crust formation, nasal regurgitation, nasal sound, and poor prosthesis fit, might occur. Continuous management and attention from prosthodontic specialists and general dentists, and modifications to existing surgical methods, must be improved continuously, such as a vomer-palatal flap to include a part of the vomer mucoperiosteum25,26.
Obstructive devices for midface reconstruction are manufactured in three stages: surgical, temporary, and final obturator.(Fig. 4) Additionally, pharyngeal obturator devices that extend posteriorly at the level of the hard palate to separate the oropharynx from the nasopharynx, and palatal augmentation prostheses that reinforce the hard palate and improve speech contact during speaking and swallowing when the entire tongue has been removed, may be considered, together.
In patients who have undergone curative or postoperative radiation therapy after midface surgery or nasopalatine cancer, implant placement may be temporarily or permanently impossible due to the risk of osteoradionecrosis. Even in this case, the production of a permanent final prosthesis is essential. There are many things to consider for successful implant prosthetic rehabilitation after radiation therapy. In particular, when implant restoration is necessary, hyperbaric oxygen therapy has been used in the past, but is gradually being replaced by preventive drug treatment by using pentoxifylline or tocopherol medications27,28.
Premaxillary defects resulting from lip or nasal excision can be reconstructed with closure alone or with a soft tissue flap connected to a dental prosthesis to maintain maxillofacial shape and support the lip and nose. To reconstruct hard tissues together, a free fibular bone-cutaneous flap can be considered, but there are problems with its relative size and the need for more than two soft tissue linings to separate the nasal cavity and oral cavity. In addition, the radial forearm osteocutaneous free flap may also be recommended. The advantage of the osteocutaneous flap is that it can be reconstructed without an additional prosthetic closure device, and the implant can be placed directly in the alveolar bone in the future.
Since this defect includes the premaxillary alveolar arch, including the canines on both sides of the maxilla, reconstruction requires hard tissue reconstruction to maintain the shape of the midface, and possibly bone reconstruction. The fibula free flap is considered first. The side of the fibula is positioned anteriorly from the orbital border to the occlusal surface of the hard palate, and the fibular blood vessel is positioned toward the maxillary sinus area, so vascular anastomosis is attempted from the cervical side.
Hard tissue reconstruction is mainly recommended for orbital floor defects after total maxilla resection, and in cases where a three-dimensional volume is required, reconstruction can be done with only a soft tissue flap. If bone grafting through postoperative radiation therapy itself is difficult, use of an allograft or titanium mesh and porous polyethylene, which are easier to apply, are recommended. In particular, transplantation of autologous bone may continue to cause difficult problems such as orbital dystrophy or enophthalmos after surgery, and absorption and infection of the bone head system, which are difficult to predict after surgery. On the other hand, alloplastic materials can be used without limitations in size and volume, and there are also joints that block all existing infections or diseases through prior immunological treatment.
Reconstruction of infraorbital structures other than the orbit, involves filling the orbital cavity with durable tissue, allowing the nasal cavity or paranasal sinuses to be distinguished, and protecting the brain if the orbital roof is removed. If the orbital cavity is deep, the retention of the prosthetic reconstruction may be excellent, but if the orbital cavity is shallow, it becomes virtually difficult to construct a reconstructive prosthesis that does not protrude convexly, so the healing process by secondary intention and granulation tissue may have to wait. Therefore, the entire treatment process to reconstruct the orbital region takes 2 to 3 months, and the wound must be managed daily with wet and dry dressings, consecutively.
In fact, the reconstructive method of filling the space by inserting a muscle flap in the orbital area has several aesthetic disadvantages, so short implants were placed in the frontal bone and zygomatic bone, and based on this retention, an implant-supporting magnet-retained silicone orbital prosthesis was created. It is possible, and it is thought that the quality of life related to systemic health can be restored in patients who have undergone facial resection and orbital reconstruction surgery in the future29-31.
Lip reconstruction can be considered according to defect size and with the same of the upper and lower lip, separately. Usually, when the defect is excised in the shape of a wedge through the external skin and internal mucosa, it is said to be a small defect where direct suturing is possible32,33. This is not a standard based on actual length but corresponds to cases of direct suture or advancement flap. On the other hand, cases that include buccal tissue or require extensive reconstruction are categorized as large, while intermediate defect cases are those in which the Karapandizc, Abbe, or Estlander flap is used32,34-36.(Fig. 5) The representative Abbe flap is one of the best and most useful methods to reconstruct a lip defect using the contralateral lip side.(Fig. 5)
There have been many articles related to only tongue reconstruction, emphasizing the various functional outcomes of the tongue. However, the function of the tongue varies greatly depending on the function and shape of the mouth floor. Therefore, it would be appropriate to consider tongue and floor of the mouth reconstruction simultaneously.(Fig. 6)
The amount and the purpose of reconstruction should be decided based on whether the defect is due to malignancy, trauma or other burns, or severe infection in the oral cavity or systemic disease37,38. For example, in congenital or acquired adhesion of the floor of the mouth, a skin graft can be performed while maintaining the function of the Wharton’s duct for sufficient reconstructive outcomes.(Fig. 6. A)39 In addition, in cases of iatrogenic trauma or chronic tongue defects, direct suturing can be performed while reducing the size of the tongue.(Fig. 6. B) For most tongue defects resulting from resection of squamous cell carcinoma, the reconstruction method must be determined according to the size of the defect and considering patient age and occupation40,41. The RFF flap can be considered in most cases for its unique characteristics of flexible and pliable skin, and the LUAF and dorsalis pedis artery (DPA) flap can be used when considering postoperative donor scars.(Fig. 6. C, 6. D). For defects in more than half of the tongue, the ALT42,43, RAM perforator flap, and RAM muscular flap are used based on the size of the defect in the floor of the mouth.
Defects of the buccal mucosa and buccal skin can be categorized as an anterior buccal mucosal defect, middle or posterior mucosal defect, or perforated buccal skin defect.(Fig. 7) The three main types of buccal mucosal reconstructions are direct closure of an anterior mucosal defect, buccal fat graft and dorsalis pedis free flap harvesting, and others44,45.(Fig. 7)
When reconstructing the buccal mucosa, two important factors must be taken into consideration: one is to preserve the function of the parotid gland by maintaining the Stensen’s canal, and the other is to preserve the amount of opening46. By inserting a thin and small cannula into the Stensen’s duct and maintaining it for more than two to three weeks (Fig. 8, left upper), continuous physiological drainage of the parotid gland can be maintained, and a pseudo parotid duct might be formed.
Over the past several decades, a large number and variety of mandibular reconstruction methods have been suggested, including antero-lateral defects, latero-posterior defects47, mandibular basal and alveolar reconstruction for latero-posterior defects48, and posterior defects including condyle and latero-posterior defects49. Flap selection should be based on the patient’s systemic condition, prioritizing medical and immune status, individual prognosis according to the tumor, analysis of functional insufficiency after resection, and donor site morbidity50-53. Accordingly, flap selection should be considered sequentially from least preferred to most likely option.
From these several criteria, we can categorize mandibular reconstructions into anterior defects mainly using a bony free flap (Fig. 8), lateral defects repaired by bony free or soft tissue free flap, latero-posterior mandible defects addressed with bone and/or soft tissue flap including angle contour restoration, and posterior defects including those of the condyle by bone and/or soft tissue flap such as PM or LD with R-plate reconstruction.(Fig. 8)
RMT cancer is most often observed as a small mucosal lesion, and if it is suspected during the first visit, the recommendation is that imaging be obtained as soon as possible. Even if it is a mucosal lesion that appears very small, most RMT cancers extend to the posterior maxilla, posterior mandible, posterior buccal mucosa, and floor of the mouth medially.(Fig. 9) Therefore, even if it is a very small lesion, the reconstruction area after removal is visualized more extensively. Most RMT reconstructions can be considered using bony continuation with the R-plate, combined with a soft fasciocutaneous flap, such as the RFF flap, LDFP, or PM flap.(Fig. 9)
To minimize decreased swallowing functions for lower jaw ablation patients, a basic trial such as a hyoid suspension suture or transhyoid laryngeal suspension must be performed with non-absorbable permanent suture materials54.(Fig. 9) Accurately repositioned laryngeal suspension can maintain and stabilize the strength of the muscles around the hyoid bone, the function of the swallowing muscles can be improved, which is beneficial to the patient’s swallowing exercises after surgery.
These patterns can be applied to the hemiglossectomy patient by drawing the thyrohyoid muscles in the anterosuperior direction by stabilizing the anterosuperior position of the epiglottis, the distance between the epiglottis and the posterior part of the tongue is shortened, which has been shown to narrow the vallecula space and decrease vallecular residue54.(Fig. 9)
Extremely complex facial tissue defects, including those of the mandible, maxilla, tongue, and even buccal mucosa muscles, might be considered as difficult challenges especially for free tissue reconstruction. Such extreme defects cannot be covered with a simple free flap, and in most cases, the LD free flap and R-plate are used.(Fig. 9) Although there are limitations in detailed functional reconstruction, current reconstruction using the latissimus dorsi free flap reconstruction plate is showing good results in extensive reconstruction of various intraoral soft tissues, including the mandibular basic funtions55. Two different microvascular and/or pedicled flaps may be useful, but conditions of the neck vessels and the patient’s comorbidities must first be confirmed56.
The surgical reconstruction of oral and maxillofacial regions must provide optimal functional and aesthetic outcomes, and basic options for the ideal oral and maxillofacial reconstruction techniques should be suggested.(Fig. 10) And anytime, reconstructed flap tissue must be coordinated with functional prosthesis. The patient’s age must be considered (e.g., pediatric patients), and reconstruction for palliative treatment must be considered separately. Above all, for the suboptimal jaw reconstruction, true reconstruction is achieved considering the final functional outcome and restoration of masticatory efficiency using implants and final prosthesis such as various types of dentures.
Furthermore, collaborative and mutual understandings between the maxillofacial reconstructive surgeon, prosthodontist, and several specialists are essential to achieve the optimized and most effective results based on multidisciplinary approaches. However, it is essential to always remember that the results of jaw and facial reconstruction are evaluated by the patient and his or her guardians.
This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (No.2022R1F1A1069624).
S.M.K. designed the study and wrote and revised the manuscript. J.H.L. prepared the patient data and advised. Both authors read and approved the final manuscript.
The study protocol and access to patient medical records had obtained ethical approval from the Institutional Review Board (IRB) of Seoul National University School of Dentistry (IRB No. S-D20220024). The study methods were performed in accordance with the relevant guidelines and regulations outlined in the Declaration of Helsinki.
No potential conflict of interest relevant to this article was reported.