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ORIGINAL ARTICLE
Year : 2017  |  Volume : 20  |  Issue : 3  |  Page : 123-128

Maxillectomy defects - to reconstruct or not? Pilot survey of Nigerian oral and maxillofacial surgeons


Department of Dental & Maxillofacial Surgery, Usmanu Danfodiyo University Teaching Hospital, Sokoto, Nigeria

Date of Web Publication16-Jan-2018

Correspondence Address:
Dr. Adebayo Aremu Ibikunle
Department of Dental and Maxillofacial Surgery, Usmanu Danfodiyo University Teaching Hospital, PMB 12003, Sokoto
Nigeria
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DOI: 10.4103/smj.smj_30_16

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  Abstract 


Background: The choice of reconstruction options for maxillectomy defects varies significantly. Factors affecting it range from the type of defect to the surgeon's expertise. This study aims to evaluate the practice of Nigerian Oral and Maxillofacial surgeons in the reconstruction of post-maxillectomy defects. Materials and Methods: The survey was conducted by use of questionnaires administered at the annual scientific meeting of the oral and maxillofacial surgeons of Nigeria in Ibadan 2012. Results: A response rate of 66.7% was achieved. All of our respondents are consultant oral and maxillofacial surgeons, 80% of whom practice in a teaching hospital. All but one of them perform maxillectomies, however only 25% of them offer surgical reconstruction of the resulting defects to patients. Flaps have been used by 25% of the respondents, while none of them has employed microvascular reconstruction. Prosthetic rehabilitation of patients is pervasive among the respondents. Conclusion: Maxillectomy defects have far-reaching consequences on patients' quality of life and attempts should be made to reconstruct such defects. Although maxillectomy is a commonly performed procedure among oral and maxillofacial surgeons in Nigeria, especially for malignancies of the oral and paranasal sinuses, surgical reconstruction of resulting defects is not so frequently done. Microvascular surgery, which is becoming a frequently utilized option among surgeons in developed nations, is still infrequently used in our environment. There is a need for oral and maxillofacial surgeons in our climes to improve their skills so as to increase the range of reconstructive options offered.

Keywords: Maxillectomy defects, reconstruction, rehabilitation


How to cite this article:
Taiwo AO, Ibikunle AA, Braimah RO. Maxillectomy defects - to reconstruct or not? Pilot survey of Nigerian oral and maxillofacial surgeons. Sahel Med J 2017;20:123-8

How to cite this URL:
Taiwo AO, Ibikunle AA, Braimah RO. Maxillectomy defects - to reconstruct or not? Pilot survey of Nigerian oral and maxillofacial surgeons. Sahel Med J [serial online] 2017 [cited 2019 Nov 21];20:123-8. Available from: http://www.smjonline.org/text.asp?2017/20/3/123/223169




  Introduction Top


Reconstructive maxillofacial surgery encompasses varying techniques and procedures aimed at restoring, remodeling, augmenting, or enhancing the form and function of soft or hard tissue structures in the maxillofacial region.[1] The human face provides a sense of both identity and esthetics. It is also the most noticeable often visible part of the body.[2] Therefore, any mutilation in this region puts the patient at risk of a myriad of problems including psychosocial dysfunction. The postablative maxillary defect classically involves the mucosal lining, bones in the midface, and the adjoining soft tissue.[3],[4]

Various indications for maxillectomy exists; prominent among them are antral malignancies, fungal infection, and chronic granulomatous lesions.[5],[6],[7] Antral malignancies, most of which require maxillectomy, are said to constitute about 28.7% of orofacial malignancies in Nigeria.[3],[8] Similarly, Adeola and Obiadazie in a retrospective study reported that maxillary tumors constituted 31.8% of orofacial malignancies.[5] Most maxillectomies performed in our environment are extensive, with most patients presenting in the late stages of the disease, thus requiring reconstruction or prosthetics fabrication for acceptable functional and esthetic outcome.[5],[6],[8],[9],[10],[11]

Reconstruction of this defect poses a significant dilemma to the surgeon.[3],[8] This is accentuated by the three-dimensional (3D) structure of the midface which fulfills both functional and esthetic roles.[3] In addition, surgeons are limited by the availability of tissue, the need to minimize flap donor site morbidity, possible compromised local vascular bed, the need for periodic oncological control, relatively high chance of recurrence, and physical condition of the patient.[4],[12] Importantly, the suitability of a type of reconstruction is dependent on the extent of the defect.[3],[10] Many attempts to classify maxillectomy defects exist in the literature, each with its own limitations.[8],[12],[13]

Correction of such defects goes far beyond esthetic considerations, so the choice between the surgical reconstruction and prosthetic restoration of large defects remains a difficult one and depends on the size and etiology of the defect, the type of defect, and patients' wish.[4] The decision to choose one of the treatment modalities is multifactorial.[14] Patients are often left with inadequate surgical reconstruction, prosthetic replacement, or no reconstruction at all.[15]


  Materials and Methods Top


The survey was conducted by use of a standardized and validated questionnaire, which was administered at the annual scientific meeting of the oral and maxillofacial surgeons of Nigeria in Ibadan 2012.[15] A total of thirty questionnaires were administered out of which twenty were completed as required. It was designed to assess the current practices of oral and maxillofacial surgeons in Nigeria.


  Results Top


A total of thirty questionnaires were administered, but twenty were duly completed, giving a response rate of 66.7%. More than half of the respondents (65%) had more than 5 years of postfellowship practice [Table 1] experience. All of our respondents were consultant oral and maxillofacial surgeons, 80% of whom practice in a teaching hospital [Figure 1]. All but one of the them (95%) stated that they perform maxillectomies in their practice.
Table 1: Responses to the questionnaire

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Figure 1: Distribution of respondents based on their hospitals

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However, only 25% of the respondents performed surgical reconstruction of the resulting maxillectomy defects. Statistically, only 25% of all the respondents have used various flaps in reconstruction of such defects. The most commonly utilized flap was the palatal rotation flap which has been used at one time or the other by 10% of the respondents. Notably, none of them have employed the use of microvascular surgery in surgical reconstruction of postablative maxillary defects. The temporalis and palatal rotation flaps were most often employed [Table 1]. Other options such as buccal fat pad were used especially in combination with prosthesis.

All of the respondents preferred placing an obturator over the defect, all of which were made of acrylic, some included the use of gutta-percha or silastic foam in the fabrication of these obturators. Responses also showed that assessment of patients for recurrence was done exclusively by the use of plain radiographs and/or computed tomography scans. None of the respondents makes use of magnetic resonance imaging and/or nasoendoscopy for monitoring potential recurrence [Table 1]. Services of restorative dentists/technicians were accessible to the majority of the respondents, only two (10%) respondents stated otherwise. In addition, 70% of the respondents felt that access to restorative services influences their decision on whether to reconstruct surgically or to use prosthesis.

The nature and extent of the tumor were the most often cited factors which influence the decision to use a prosthetic or surgical reconstruction; 85% of the respondents indicated this. It was followed closely by availability of restorative services, which was stated as an important factor by 65% of the respondents. Patient preference was least often considered as a factor in deciding whether to surgically reconstruct or to use prosthesis. It was cited by only 35% of the respondents as a factor that influences their choice of reconstruction option.

None of the respondents had used nasoendoscopy as a means of identifying recurrences; however, most of them claimed that if they were to use nasoendoscopy, they would use it before the development of clinically positive cervical lymph nodes. In cases where surgical reconstruction was not performed, all of the respondents (100%) used acrylic prosthesis with or without gutta-percha/silastic foam. Only 11.1% of respondents had used implants as an adjunct in the maxillary reconstruction.


  Discussion Top


Several attempts at classifying maxillectomy defects have been made. Some authors have proposed that to improve the comprehensiveness of maxillectomy defect classifications, both horizontal and vertical dimensions of the defects should be represented.[10],[14] Most patients in our environment present late, with majority in Stages III and IV at presentation, thus necessitating the need for total maxillectomy in them.[6],[9],[11] A total of sixty-nine oral and maxillofacial surgeons practice in Nigeria; however, the scientific conference had only 31 oral and maxillofacial surgeons in attendance.

Defects in maxillofacial structures result in considerable mental, physical, and psychological agony to a person's self-esteem.[16] A maxillectomy defect creates a communication between the oral and nasal cavities, and the defects may further involve the orbit, thereby producing substantial functional and esthetic problems.[12],[13] This current study revealed that most oral and maxillofacial surgeons in Nigeria perform maxillectomies, and majority of them offer prosthetic rehabilitation. However, only a quarter of the respondents (25%) perform surgical reconstruction of the maxillectomy defects.

Maxillary reconstruction is still developing in comparison to mandibular reconstruction, and as such, there is no consensus on the best techniques for reconstruction.[14],[17] Reconstruction of maxillectomy defects is demanding because of its complex structural architecture.[18],[19] Postablative rehabilitation of patients with maxillary defects is either by surgical reconstruction or prosthetic rehabilitation.[14]

A large percentage of our respondents (90%) have access to the services of a restorative dentist or technician which may explain their inclination toward prosthetic rehabilitation rather than surgical reconstruction of postablative maxillary defects. It must be noted that restorative dentists are few in Nigeria and are only available in selected centers. However, in the absence of a substantive restorative dentist, dental technicians often play a vital role in the fabrication of prosthesis for patients. About 60% of our respondents claim that the availability of restorative dentists/dental technician may have influenced their decision not to reconstruct the maxillary defects surgically. The use of implants as reported by our respondents is still very sparse in our environment as only 10% of them claim to have used implants as adjuncts in reconstruction.

Prosthetic reconstruction is widely popular in the rehabilitation of patients with large facial defects especially those involving the maxillary-orbital complex following surgical resection of tumors [3],[14] because of the ease of fabrication, no donor site morbidity, and low cost.[20] To improve retention and tolerance, the use of implants, magnets, and skin grafts have been advocated.[20] In recent times, computerized 3D data processing has been employed in the fabrication of obturators by the use of computer aided designs and rapid prototyping systems, thus obviating the need for traditional impressions.[16],[21],[22]

Advantages of obturators especially when deployed immediately postoperatively include improving patients' swallowing ability which may have adverse effect on the recovery period, reduction in speech alteration, improved hygiene, and absence of donor site morbidities.[23]

Most of the respondents cited nature and extent of the tumor as the most important factors which influence the decision to use prosthetic or surgical reconstruction. This is in agreement with reports by Davison et al. and Okay et al.[13],[10] Extent of the tumor will determine the amount of residual tissue which in turn has an effect on the retention and stability of prosthetic replacements or indeed if only surgical reconstruction will suffice. Prosthetic obturators remain a good solution for some patients with limited defects. For extensive defects, obturators may be difficult or impossible to retain, particularly in edentulous patients.[12]

Prosthetic reconstruction of maxillectomy defects remain common, and it still provides a good option for reconstruction in many institutions.[3],[12] Indeed, some authors have posited the superiority or equality to the use of flaps.[24],[25] Rogers et al.[26] compared the quality of life (QOL) between two groups of patients having either prosthetic or surgical obturation of postablative maxillectomy defects. Their results revealed no statistically significant differences between the obturator and free flap groups although they reported minor trends for obturator patients being more self-conscious, concerned about their appearance, and experiencing more pain and soreness in their mouths. They were also deemed to be less satisfied with their upper dentures and function. Proponents of the use of prosthetic obturators also claim that the surgical bed can be easily monitored for recurrence.[27]

Disadvantages of obturators have been highlighted by different authors, including the potential for hypernasality, regurgitation of foods and liquids, difficulty in maintaining hygiene, difficult retention, especially in cases of complete edentulousness or total maxillectomy and the need for repeated prosthesis adjustments due to progressive changes in the size and shape of the palatal defect, especially in patients who receive radiation therapy.[13] Assortments of local and regional flaps and even combinations of the two have been employed in the reconstruction of maxillary defects.[3],[12] Regrettably, all these options are constrained by a paucity of available bone and soft tissues, limited length of the vascular pedicle, concerns about reliability, and the possible need for staged procedures.[3],[12]

Over 50% of the respondents employed the use of acrylic plates or obturators postsurgically; while this may not be ideal, it is a better option than giving no intervention. A substantial proportion of the respondents felt that the access to restorative services influences their decision on whether to reconstruct surgically or to use prosthesis.

Availability of these services may have influenced their decision to reconstruct using prosthesis. All of the respondents employed the use of acrylic prosthesis in patients who did not have surgical reconstruction done. In recent times, there has been a shift toward surgical reconstruction which is deemed preferable to the use of prosthesis.[12],[15] This is supported by the study of Alani et al., where only 8.6% of the respondents did not reconstruct surgically, though they did not state the exact options utilized in such cases.[15]

Pedicled flaps, which were once the mainstay of surgical reconstruction, are losing popularity in recent years because of limitations in reach, volume, and attendant donor site morbidity.[12] However, small and simple defects may be resolved easily with the use of local flaps which often provides a good match for the lost tissue. Furthermore, none of the respondents had used a microvascular flap in reconstruction of postablative maxillectomy defects although recorded cases of microvascular tissue transfer in Nigeria exist.[28] This is in contrast to the results of studies done in the United Kingdom, which showed a much higher use of microvascular reconstruction.[3],[16]

Soft tissue or composite free flaps are now more often utilized than in yesteryears, owing to improved knowledge.[29] This may be said to offer the closest option to comply with Gilles' principle of replacing like with like.[30] The use of microvascular surgery has changed the face of reconstruction of postablative defects.[29] Initially, microvascular reconstruction in the maxillofacial region was often a long and difficult procedure.[29] However, several recent advancements in microvascular reconstruction over the past decade such as automatic hemoclip appliers, bipolar scissors, anastomotic couplers, and better visualization have significantly enhanced surgery outcome and surgeon efficiency.[17],[29] More than 18 donor sites for microvascular surgical reconstruction of head and neck defects have been identified.[31] However, microvascular surgery is not without its own disadvantages. Microvascular surgery is technically demanding, relatively expensive, time-consuming; it has a steep learning curve and often requires long operation time and hospital stay.[29],[32],[33]

Tissue engineering is a form of regenerative medicine which culminates in the development of a 3D living structure by careful selection and combination of four factors, which are, scaffold, growth factors, extracellular matrix, and cells.[33] It has been proposed to be one of the options for this nagging reconstructive problem; however, it has not given reliable and reproducible results so far.[14] Furthermore, it has been bedeviled by ethical, social, and legislative debates.[33],[34],[35]

In addition to visual inspection, the respondents monitored recurrence in patients radiologically with the aid of either plain radiographs and/or computed tomography scans. The observed nonuse of magnetic resonance imaging and nasoendoscopy may have been due to a combination of factors, including inadequate facilities, affordability, and availability. Moreno et al.[36] who compared the average time of presentation following recurrence between individuals who had surgical obturation and those who had prosthetic obturation of their maxillectomy defects found no statistically significant difference.[14] Furthermore, Moreno et al.[36] observed that recurrence was more often detected by physical examination, than by imaging techniques.

Nigeria is a largely low-resource environment with the challenges of limited theater time, high incidence of late presentation, and financial incapacitation among patients.[11],[37] Hence, the postablative maxillectomy defects are often large. In addition, the maxilla has an intricate structure which is difficult to reconstruct. The anatomic complexity of the maxilla may be attributed to its 3D structure.[10] These challenges may explain the low proportion of the respondents who perform surgical reconstruction of maxillectomy defects in this environment.

Furthermore, none of the respondents use microvascular surgery; reasons for this may be attributed to the financial incapacitation on the patients' part as well as the health status of patients. A large proportion of patients in Nigeria present in advanced stages of disease.[37] Therefore, a significant proportion of them may be unfit for microvascular surgery.


  Conclusion Top


Maxillectomy defects have far-reaching consequences on patients' QOL, and attempts should be made to reconstruct such defects. Although maxillectomy is a commonly performed procedure among oral and maxillofacial surgeons in Nigeria, surgical reconstruction of resulting defects is not so frequently done. There is a need to improve on the options offered for dental rehabilitation of patients following maxillectomy.

Limitations

Not all oral and maxillofacial surgeons practicing in Nigeria were included in this study. However, this is a pilot study, and a more encompassing study is being planned.

This study is a survey which was dependent on the recall ability of the respondents. Therefore, some recall bias or omissions may have occurred.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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