Maxillary reconstruction using the “Autoplan” software suite

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INTRODUCTION

Modern facial injuries caused by new types of weapons, increased vehicle speeds, and diagnosed malignancies pose a serious surgical challenge. According to statistics, the number of facial injuries has more than doubled over the past decade¹.

Injuries resulting from a variety of impact mechanisms result in multiple injuries to both soft and hard facial tissues. For example, fractures of the upper jaw are often combined with eye socket injuries and damage to the soft tissues of the face [1]. This requires a comprehensive approach to treatment, including surgical intervention and restorative therapy.

With respect to defects of the maxilla, the main tasks are the elimination of oronasal fistula, restoration of the lower wall of the orbit to ensure the supporting function of the eyeball, restoration of the functions of chewing, swallowing, breathing, speech, as well as the implementation of complete dental rehabilitation.

An important practical area is the customization of surgical interventions based on the patient's anthropometric data. Taking into account the unique anatomical features of the patient ensures good functional and aesthetic results, which opens up new horizons for the successful rehabilitation of patients with complex facial defects [2].

There are numerous classifications of maxillary defects. One of the latest is the classification of J.S. Brown (2010), based on the identification of the vertical and horizontal components of the defect. Depending on the presence of the anastomosis between the oral and the nasal cavity, involvement of the supporting structures of the eye socket in the defect, the scope of damage of the hard palate and some other parameters, the authors suggested six types of defects [3].

Today’s clinical practices place more importance on the customized approach, modern systems of visualization, surgery planning combined with involvement of additive technologies. 3D-modeling enables reproduction of precise stereolithographic models on the stage of planning of reconstruction based on the patient’s anthropometric data [4]. The use of individual templates provides the possibility of reaching high precision of congruence of the bony surfaces of the flap and recipient wound, reducing surgery time and yielding better functional and aesthetic results of reconstructive plastic surgery [5, 6].

AIM

To develop a three-stage algorithm for maxillary reconstruction with the Autoplan software suite to improve the results of surgical treatment.

MATERIAL AND METHODS

A randomized controlled trial was conducted involving 110 patients with maxillary defects of post-traumatic and post-oncological etiology. The participants of the study were divided into two groups, the main and the control group. The main group included 60 people, average age of 46±11 years, men to women ratio: 46/14. The control group included 50 people, average age of 47±12 years, men to women ratio: 39/11.

In accordance with the J.S. Brown’s classification of maxillary defects (2010), four types of defects were identified (Type I-IV).

Type I: lower combined defects of the maxilla, predominantly with a horizontal component, affecting the mucous membrane of the retromolar region, the soft palate region and the lateral wall of the oropharynx (main group: 23 patients; control group: 16 patients).

Type II: defects resulting from total maxillectomy (main group: 13 patients; control group: 12 patients).

Type III: partial defect of the maxilla, predominantly with a vertical component (main group: 15 patients; control group: 13 patients).

Type IV: inclusion of the orbit with its exenteration (main group: 9 patients; control group: 9 patients).

In the main group of patients with combined maxillary defects, the surgery planning, performance and follow-up involved a three-stage algorithm and the Autoplan software suite. In the control group, surgery was performed under conventional methods.

Surgery algorithm. The algorithm used to perform the surgery in the main group consisted of three stages. The first stage is preoperative planning: the patient’s head CT data was uploaded to the Autoplan software suite. 3D-model of bony structure and soft tissue is constructed automatically; the defect is visualized and localized, its scope and area were calculated. For plastic material, four types of free surgical flaps were used: maple seed-shaped fasciocutaneous radial flap [7], chimeric scapular flap, ALT-flap (anterolateral thigh), and fibula flap. The selection of the suitable plastic material was performed in the automatic flap selection program², based on the following parameters: area, scope and composition of the defect, necessity of cavity plugging. If the selected flap was fibular or scapular, additional CT was performed of the lower leg or the scapular region, respectively. The data was uploaded to the Autoplan software suite, where the 3D model of the flap was constructed with fitting in the defect area. This stage also included construction of 3D models and construction of individual templates for resection, flap modeling and fixation system.

The second stage is the surgery. During the surgery, individual templates for re-resection were used to refresh the bonesaw lines of the recipient area, isolation and modeling of the flap were performed using individual templates and fixation system with retained blood flow in the autogenetic graft.

In the third stage, the modeled flap was repositioned to the recipient area and partially attached to the bonesaw lines of bony structures. Microsurgery was then performed to form the anastomoses with subsequent final fixation of the flap and suture of the wound.

The postoperative results in both groups were assessed six months after the operation. The criteria studied were the results of the functional (binocular vision, dietary restrictions, speech disorders) and aesthetic aspects; the amount of time spent on the surgical stage; the incidence of post-surgery complications. For each of the parameters, the functional result was assessed as ‘good’, ‘satisfactory’, or ‘poor’. The aesthetic results were assessed using the FACE-Q scales, depending on the score, the ‘good’ (≥80 points), ‘satisfactory’ (65-79 points), ‘poor’ (≤64 points) evaluations were given.

Data processing. Using descriptive statistics, mean values and standard deviations were obtained. Statistical tests were used to determine the statistically significant α< 0,05 difference between the values in the control and the main groups. To assess the significance of differences between groups, Student’s T-test and Pearson’s χ² were used. IBM SPSS Statistics 23 software suite was used for statistical calculations.

RESULTS

Reconstructive plastic surgeries were performed on 110 patients with defects of the upper jaw (N=60 in the main group, N=50 in the control group). The autogenetic graft used in the main group were distributed as follows: 22 – radial flap, 22 – ALT-flap, 14 – scapular flap, and 2 – fibula flap. The autogenetic graft used in the control group were distributed as follows: 17 – radial flap, 20 – ALT-flap, 12 – scapular flap, and 1 – fibular flap (Table 1).

 

Table 1. Plastic material used for maxillary reconstruction in the main and control groups. O – main group, K – control group

Таблица 1. Аутотрансплантаты, примененные для реконструкции верхней челюсти в основной и контрольной группе. О – основная группа, К – контрольная группа

Flap type	Type I		Type II		Type III		Type IV		Total		TOTAL
	О	К	О	К	О	К	О	К	О	К	О+К
Fibular	2 (66.7%)	1 (33.3%)	—	—	—	—	—	—	2 (66.7%)	1 (33.3%)	3 (2.7%)
Scapular	4 (15.4%)	3 (11.5%)	10 (38.5%)	9 (34.6%)	—	—	—	—	14 (53.8%)	12 (46.2%)	26 (23.6%)
ALT-flap	4 (9.5%)	3 (7.1%)	3 (7.1%)	3 (7.1%)	6 (14.3%)	5 (11.9%)	9 (21.4%)	9 (21.4%)	22 (52.4%)	20 (47.6%)	42 (38.2%)
Radial flap	13 (33.3%)	9 (23%)	—	—	9 (23%)	8 (20.5%)	—	—	22 (56.4%)	17 (43.6%)	39 (35.5%)
Total:	23 (20.9%)	16 (14.5%)	13 (11.8%)	12 (10.9%)	15 (13.6%)	13 (11.8%)	9 (8.2%)	9 (8.2%)	60 (54.5%)	50 (45.5%)	110 (100%)

 

Assessment of aesthetic results. Before the surgery the average score as per the FACE-Q questionnaire was similar in both groups and was 51 points (with quartiles: Q1 - 45, Q2 - 51, Q3 - 57). The assessment 6 months after the surgery yielded the following average scores: in the main group, 79 points (Q1 - 74, Q2 - 79, Q3 - 93); in the control group, 67 points (Q1 - 64, Q2 - 67, Q3 - 80) (p<0.001). God aesthetic results were achieved in 29 (48.33%) patients of the main group and in 17 (34%) patients of the control group. Satisfactory results: 25 (41.67%) patients of the main group;21 (42%) patients of the control group. Poor results: 6 (10%) patients of the main group and 12(24%) patients of the control group.

Assessment of functional results. Speech: good quality of speech was seen in 31 (86.11%) patients of the main group and 22 (78.57%) patients of the control group; satisfactory, in 3 (8.33%) / 3 (10.71%) patients; poor, in 2 (5.56%) / 3 (10.71%) patients, respectively (p<0.05, p=0.047).

Diet. Of the 36 patients of the main group and 28 patients of the control group with maxillary defects of Type I and Type II, for 26 (72.22%) / 18 (64.29%) patients there were no dietary restrictions; 9 (25%) / 8 (28.57%) patients required strained food; 1 (2.78%) / 2 (7.14%) patients required a fluid diet (p<0.05, p=0.042).

Visual acuteness and eye position. Decrease in visual acuteness was not identified at all. In the group of patients with Type II and Type III defects (N=28 / 25) symmetry in the eyeball position was achieved in 23 (82%) / 17 (68%) of the cases; moderate diplopia was seen in 4 (14%) / 7 (28%) of the cases; enophthalmos was seen in 1 (4%) /1 (4%) of the cases, respectively (p<0.05, p=0.032).

Thus, the implementation of the three-stage algorithm allowed achievement of good functional and aesthetic results in the greater number of cases. The differences between the main and the control group are statistically significant (p<0.05) (Tables 2, 3).

 

Таблица 2. Функциональные и эстетические результаты устранения дефектов верхней челюсти у пациентов основной группы

Table 2. Functional and aesthetic results of maxillary reconstruction in the main group

Defect Type	TypeI (N=23)	TypeII (N=13)	TypeIII (N=15)	TypeIV (N=9)	TOTAL	P
Speech quality					N=36	p=0.047
Good	21 (91.3%)	10 (76.92%)	-		31 (86.11%)
satisfactory	2 (8.7%)	1 (7.69%)	-		3 (8.33%)
Poor	-	2 (15.38%)	-		2 (5.56%)
Diet			-		N=36	p=0.042
No restrictions	19 (82.61%)	7 (53.85%)	-		26 (72.22%)
Strained food	4 (17.39%)	5 (38.46%)	-		9 (25%)
Liquid diet		1 (7.69%)	-		1 (2.78%)
Aesthetic result					N=60	(p<0.001)
Good	18 (78.26%)	7 (53.85%)	4 (26.67%)		29 (48.33 %)
satisfactory	4 (17.39%)	3 (23.08%)	9 (60%)	9 (100%)	25 (41.67 %)
Poor	1 (4.35%)	3 (23.08%)	2 (13.33%)		6 (10%)
Eyeball position					N=28	p=0.032
symmetrical	-	10 (76.9%)	13 (86.67%)		23 (82%)
diplopia	-	2 (15.4%)	2 (13.33%)		4 (14%)
enophthalm	-	1 (7.7%)	0		1 (4%)

 

Table 3. Results of surgical treatment of patients with maxillary defects in the control group

Таблица 3. Функциональные и эстетические результаты устранения дефектов верхней челюсти у пациентов контрольной группы

Defect Type	TypeI (N=16)	TypeII (N=12)	TypeIII (N=13)	TypeIV (N=9)	TOTAL
Speech quality					N=28
Good	13 (81.25%)	9 (75%)	-		22 (78.57%)
satisfactory	2 (12.5%)	1 (8.33%)	-		3 (10.71%)
Poor	1 (6.25%)	2 (16.67%)	-		3 (10.71%)
Diet			-		N=28
No restrictions	12 (75%)	6 (50%)	-		18 (64.29%)
Strained food	4 (75%)	4 (33.33%)	-		8 (28.57%)
Liquid diet		2 (16.67%)	-		2 (7.14%)
Aesthetic result					N=50
Good	10 (62.5%)	5 (41.67%)	2 (5.38%)		17(34%)
satisfactory	4 (25%)	3 (25%)	6 (46.15%)	8 (88.89%)	21 (42%)
Poor	2 (12.5%)	4 (33.33%)	5 (38.46%)	1 (11.11%)	12 (24%)
Eyeball position					N=25
symmetrical	-	7 (58.33%)	10 (76.92%)		17 (68%)
diplopia	-	4 (33.33%)	3 (23.08%)		7 (28%)
enophthalm	-	1 (8.33%)	0		1 (4%)

 

The time required to perform the reconstructive stage of the surgery, depending on the selected graft, is shown in Table 4. Scapular flap: in the main group, the average time was 210 (35) minutes, in the control group, 300 (35) minutes (time reduced by 30 (13.4)%). Fibular flap: 180 (16) min / 260 (36) min (time reduced by 30.77 (11.2)%). ALT flap: 175 (17) min / 220 (33) min (time reduced by 20.45 (13.3)%). Radial fasciocutaneous flap: 130 (12) min / 170 (12) min (time reduced by 23.53 (8.1%). The differences both in the average time of reconstructive stage and in the total time of the surgery in the main and the control group are significant (p<0.001).

 

Table 4. Mean surgery time in the main and control groups

Таблица 4. Среднее время оперативного вмешательства в основной и контрольной группах

	Main group				Control group
Flap type	Angle of scapula	Fibular	ALT	Radial	Angle of scapula	Fibular	ALT	Radial
Surgery time, min	500 (52)	475 (78)	390 (65)	290 (56)	610 (66)	580 (74)	450 (71)	330 (67)
Flap modeling time, min	90 (12)	75 (13)	85 (8)	30 (4)	180 (57)	160 (24)	120 (8)	70 (6)
Reconstructive stage time, min	210 (33)	180 (15)	175 (16)	130 (12)	300 (33)	260 (34)	220 (32)	170 (11)

 

DISCUSSION

The region of the head and the neck is crucial in the functions of chewing, swallowing, breathing, and speech; moreover, it is vital for social interactions. Aesthetic and functional facial defects are detrimental to the patient’s quality of life [8], therefore, their repair is required for medical reasons [9-11].

To repair the defects in the middle region of the face and the maxilla, removable exoprostheses are usually used that isolate the oral and the nasal cavities, thus restoring the speech and the swallowing functions. The prosthesis may include dental elements that contribute to a satisfactory aesthetic result. One of the major advantages of this method is fast achievement of the desired result, a shorter and less invasive plan of surgical treatment without the lengthy period of rehabilitation.

In patients undergoing cancer treatment, prostheses provide the possibility of direct visual control, but given the availability of modern imaging techniques, this potential advantage has not been confirmed [12]. In addition, prostheses require daily care and must be removed and cleaned regularly, which can be a major problem for older people or those with visual impairments. In some cases, the exoptostheses may be an acceptable method for the repair of maxillary defects; however, their use can not restore the functions as effectively as the free autogenetic graft can [13].

Scientific literature currently describes a considerable number of microsurgical methods to repair the maxillary defects, including the rib osteo-cutaneous flap [14], latissimus dorsi muscle-cutaneous flap [15], scapular flap [16], rectus abdominis muscle flap [17], osseous radial flap [18], fibular flap [19, 20], and some others [21-23]. The use of the method we propose allows achievement of better functional and aesthetic results in comparison with other methods [24, 25].

Additive technologies allow achieving higher rates of bone surface congruence and reducing surgery time [26].

The three-stage algorithm of reconstructive plastic surgery proposed by us for patients with facial defects allows reducing the surgery time by 17.4% in comparison with conventional techniques. E.g., B. Barton et al. (2022) report that the time for reconstruction of the maxilla with the flap involving the scapular angle is 600 minutes [27]. In fact, this aligns with the time of surgery in the control group of our study (610 minutes), whereas in the main group, where the three-stage algorithm and the Autoplan software suite were used, the average time of surgery was reduced to 500 minutes.

The use of standardized algorithms for constructing a patient's surgical treatment trajectory helps to improve the reproducibility of such complex operations [28, 29].

CONCLUSION

We propose an approach that includes three stages of reconstructive plastic surgeries for patients with facial defects. It allows achieving better results of surgical treatment, reducing the time of surgical intervention and getting fewer complications in comparison with conventional approaches. We also believe that the presented method will reduce the time required for training of surgeons in this area.

 

¹ Federal Service of State Statistics: traumatism statistics in Russia. Available online: https://rusind.ru/statistika-travmatizma-v-rossii-po-rosstatu.html

 

² Certificate of state registration of the computer program: RUS №2024617819 dated 05.04.2024. Available online: https://fips.ru/registers-doc-view/fips_servlet?DB=EVM&DocNumber=2024617819&TypeFile=html

 

ADDITIONAL INFORMATION	ДОПОЛНИТЕЛЬНАЯ ИНФОРМАЦИЯ
Study funding. The study was the authors’ initiative without external funding.	Источник финансирования. Работа выполнена по инициативе авторов без привлечения финансирования.
Conflict of interest. The authors declare that there are no obvious or potential conflicts of interest associated with the content of this article.	Конфликт интересов. Авторы декларируют отсутствие явных и потенциальных конфликтов интересов, связанных с содержанием настоящей статьи.
Compliance with Ethical Standards. The authors confirm that the rights of the people who participated in the study were respected, including obtaining informed consent. The study protocol was approved by the local Ethics Committee (protocol No. 156863 dated 20.10.2024).	Соответствие нормам этики. Авторы подтверждают, что соблюдены права людей, принимавших участие в исследовании, включая получение информированного согласия. Протокол исследования был одобрен ЛЭК (протокол № 156863 от 20.10.2024 г.).
Contribution of individual authors. V.Yu. Ivashkov, A.V. Kolsanov: design of the study, scientific editing. E.V. Verbo, A.N. Nikolaenko: scientific editing. A.S. Denisenko, A.Yu. Legonkikh: review of publications on the article topic, writing of the article, collection and processing of the material. All authors gave their final approval of the manuscript for submission, and agreed to be accountable for all aspects of the work, implying proper study and resolution of issues related to the accuracy or integrity of any part of the work	Участие авторов. В.Ю. Ивашков, А.В. Колсанов – создание дизайна исследования, научное редактирование; Е.В. Вербо, А.Н. Николаенко – научное редактирование. А.С. Денисенко, А.Ю. Легоньких – обзор публикаций по теме статьи, написание текста статьи, сбор и обработка материала. Все авторы одобрили финальную версию статьи перед публикацией, выразили согласие нести ответственность за все аспекты работы, подразумевающую надлежащее изучение и решение вопросов, связанных с точностью или добросовестностью любой части работы.

About the authors

Vladimir Yu. Ivashkov

Samara State Medical University

Email: v.yu.ivashkov@samsmu.ru
ORCID iD: 0000-0003-3872-7478

MD, Cand. Sci. (Medicine), Chief Scientific Advisor of the NTI Center for Bionic Engineering in Medicine

Russian Federation, Samara

Aleksandr S. Denisenko

Samara State Medical University

Author for correspondence.
Email: allexander.pafem@gmail.com
ORCID iD: 0000-0002-6791-2237

Resident of the Department of Plastic Surgery

Russian Federation, Samara

Aleksandr V. Kolsanov

Samara State Medical University

Email: a.v.kolsanov@samsmu.ru
ORCID iD: 0000-0002-4144-7090

MD, Professor of the Russian Academy of Sciences, Rector

Russian Federation, Samara

Elena V. Verbo

Russian Medical Academy of Continuous Professional Education

Email: plasticrmapo@gmail.com
ORCID iD: 0000-0001-9843-5026

MD, Dr. Sci. (Medicine), Professor of the Department of Plastic and Maxillofacial Surgery

Russian Federation, Moscow

Andrei N. Nikolaenko

Samara State Medical University

Email: a.n.nikolaenko@samsmu.ru
ORCID iD: 0000-0003-3411-4172

MD, Dr. Sci. (Medicine), Director of the Research Institute of Bionics and Personalized Medicine

Russian Federation, Samara

Aleksandr Yu. Legonkikh

Samara State Medical University

Email: aleksandr.mox.fox@gmail.com
ORCID iD: 0009-0005-3259-547X

MD, plastic surgeon

Russian Federation, Samara

References

Supplementary files