Evaluation of maxillary sinus after Le Fort I osteotomy using various fixation materials

Journal of Cranio-Maxillo-Facial Surgery 45 (2017) 552e557

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Evaluation of maxillary sinus after Le Fort I osteotomy using various fixation materials Koichiro Ueki*, Kunio Yoshizawa, Akinori Moroi, Asami Hotta, Takamitsu Tsutsui, Kenichi Fukaya, Ryota Hiraide, Akihiro Takayama, Tatsuya Tsunoda, Yuki Saito, Ran Iguchi, Akihiko Kosaka, Hiroumi Ikawa Department of Oral and Maxillofacial Surgery (Head: Prof. Dr. K. Ueki), Division of Medicine, Interdisciplinary Graduate School, University of Yamanashi, 1110 Shimokato, Chuo-shi, Yamanashi, 409-3898, Japan

a r t i c l e i n f o

a b s t r a c t

Article history: Paper received 6 October 2016 Accepted 23 January 2017 Available online 31 January 2017

Purpose: The purpose of this study was to evaluate maxillary sinus and predict the factors affecting the postoperative sinus condition after Le Fort I osteotomy using various fixation materials. Materials and methods: The study subjects consisted of 71 patients (21 male and 50 female, 142 sides) who underwent Le Fort I osteotomy with sagittal split ramus osteotomy. The maxillary sinus bony area and the inside air area were measured in the coronal plane across the mesial aspect of the first molar perpendicular to the Frankfurt horizontal plane of a computed tomography (CT) image preoperatively and at 1 week and 1 year after surgery. The rate of intact sinus area (the inside air area/the maxillary sinus bony area) was calculated. Subjects were divided into groups according to gender, preoperative diagnosis (Angle class II and III with and without asymmetry), plate fixation material (PLLA and uHA/ PLLA), and use or non-use of bone alternative material (a-tricalcium phosphate). Statistic comparisons between groups were performed in each division. Furthermore, age, operation time, amount of blood loss, and direction and amount of movement were examined as the continuous variables to statistically predict the rate of intact sinus area after 1 week and 1 year. Results: The rate of intact sinus area after 1 week was significantly correlated with age, amount of anterio-posterior movement, and preoperative rate of the intact sinus area (p < 0.0001). Rate of intact sinus area after 1 year was significantly low in the group that used the bone alternative material compared to the group that did not (p < 0.0282). Conclusion: The study suggests that the bone alternative material might be a cause of inflammation in the sinus after 1 year. Moreover, attention needs to be paid to older age, backward movement of the maxillary segment, and preoperative sinusitis including hypertrophy of sinus membrane in Le Fort I osteotomy. © 2017 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Keywords: Le Fort I osteotomy Maxillary sinus Fixation material Bone alternative material Computed tomography

1. Introduction Le Fort I osteotomy is frequently used in combination with mandibular osteotomy for maxillary deformity. Many complications of Le Fort I osteotomy occur from unfavorable dysjunction of the pterygoid plates from the posterior maxillary wall, including excessive bleeding, cranial nerve injury, and carotid artery injury (Steel and Cope, 2012). A previous review on the incidence of

* Corresponding author. Fax: þ81 55 273 8210. E-mail address: [email protected] (K. Ueki).

complications and problems related to orthognathics revealed that the most common complication is neurosensory deficit in inferior alveolar nerves after mandibular surgery, as well as intraoperative bleeding (Panula et al., 2001). Postoperative maxillary sinusitis is uncommon after Le Fort I osteotomy. Therefore, there are few studies on the postoperative maxillary sinus situation after Le Fort I osteotomy (Nocini et al., 2016). In Le Fort I osteotomy, various alternative materials have sometimes been used between the segments to obtain long-term stability. In earlier days, autogenous bone from the iliac crest or rib was recommended (Araujo et al., 1978; Bloomquist, 1980, 1982), although freeze-dried bone (Epker et al., 1976), proplast blocks

http://dx.doi.org/10.1016/j.jcms.2017.01.027 1010-5182/© 2017 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

K. Ueki et al. / Journal of Cranio-Maxillo-Facial Surgery 45 (2017) 552e557

(Burton et al., 1980), and the solid-block form of hydroxyapatite were also advocated (Kent et al., 1986). Demineralized bone matrix or iliac corticocancellous graft were also used for Le Fort I osteotomy interpositional graft (Lye et al., 2008; Posnic and Sami, 2015). Self-setting a-tricalcium phosphate (Biopex®; Pentax Co, Tokyo, Japan) has also been recognized as one of the most useful bone alternative materials (Monma et al., 1988; Ueki et al., 2013), and has been used in Japan. An absorbable plate system has been newly developed and frequently used in orthognathic surgery, and there have been many studies that proved the usefulness and skeletal stability of the absorbable plate (Ueki et al., 2005, 2006, 2011a,b). Although studies on postoperative stability and nerve disturbance after Le Fort I osteotomy have been reported, no report has evaluated the effect of the maxillary sinus following use of various fixation materials. The purpose of this study was to evaluate the maxillary sinus and to predict the factors affecting the postoperative sinus condition after Le Fort I osteotomy with the use of various fixation materials by computed tomography (CT). 2. Materials and methods 2.1. Study patients The study subjects were 73 Japanese adults (male, 23; female, 50) with jaw deformities who underwent Le Fort I osteotomy with sagittal split ramus osteotomy (SSRO). At the time of orthognathic surgery, the patients ranged in age from 16 to 54 years, with a mean age of 27.6 years (standard deviation, 9.4 years). Although this study was retrospective, informed consent was obtained from the patients, and the study was approved by the ethical committee of clinical study of Yamanashi University Hospital. 2.2. CT assessment Computed tomography was performed in all patients, preoperatively, immediately after surgery, and after 1 year. The patients were placed in the gantry with the tragacanthal line perpendicular to the ground for CT scanning. They were instructed to breathe normally and to avoid swallowing during the scanning process. CT scans were obtained in the radiology department by skilled radiology technicians using a high-speed, advantage-type CT generator (Light Speed Plus; GE Healthcare, Milwaukee, WI, USA) with each sequence taken 1.25 mm apart for three-dimensional (3D) reconstruction (120 kV, average 150 mA, 0.7 s/rotation, helical pitch 0.75). A total of 146 sides (73 right and 73 left sides) were measured. The maxillary sinus bony area and the inside air area were measured in the coronal plane across the mesial aspect of the first molar perpendicular to the Frankfurt horizontal plane of CT. The rate of intact sinus area (the inside air area/the maxillary sinus bony area) was calculated using an image software (ImageJ; the Research Services Branch, National Institute of Mental Health, Bethesda, MD, USA) and SimPlant O & O (Materialise Dental n.v., Leuven, Belgium) (Figs. 1e3). All CT images were measured by one author (K.U.). Fifteen patients were selected, and the calculation was performed using Dahlberg's formula (Dahlberg, 1940):

ME ¼

2.3. Statistical analysis For the statistical analysis, groups were categorized based on the following: 1) Gender (male vs female) 2) Preoperative diagnosis (Angle class II vs III) and (symmetry vs asymmetry) 3) Plate fixation material (PLLA vs uHA/PLLA vs titanium). The two fixation materials were as follows. PLLA group: 4 PLLA L-type mini-plates (10  22  1.5 mm with 4 screws (2  6 mm), Fixorb®-MX; Takiron Co., Osaka, Japan), uHA/PLLA group: 4 uHA/PLLA L-type mini-plates (10  22  1.4 mm with 4 screws (2  6 mm), Super-Fixorb®-MX; Takiron Co., Osaka, Japan). 4) Use of bone alternative material: self-setting a-tricalcium phosphate (a-TCP) (Biopex®; Pentax Co, Tokyo, Japan) (Fig. 4) (yes vs no) 5) Removal of the interference between the pterygoid plate and posterior site of the maxillary bone using ultrasonic bone curette (yes vs no) Furthermore, age, operation time, amount of blood loss, amount and direction of movement, and preoperative and 1 week postoperative rate of intact sinus area were selected as the continuous variables to statistically predict the rate of intact sinus area after 1 week and 1 year. For the amount of anterior-posterior movement, a positive value indicated advancement and a negative value indicated setback at the A point. For the amount of lateral movement, a positive value indicated movement to the right and a negative value indicated movement to the left at the A point. For the amount of impaction in the anterior site, a positive value indicated impaction movement and a negative value indicated downward movement at the midpoint of the bilateral incisor edge. For the amount of impaction in the right molar site, a positive value indicated impaction movement and a negative value

qffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi  S d2 2n

where d is the difference between two registrations of a pair, and n is the number of double registrations. The random errors did not exceed 2.0 mm2 for the square measurements.

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Fig. 1. Preoperative coronal computed tomographic image.

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Fig. 4. Intraoperative photograph using a-tricalcium phosphate (a-TCP).

was used for the continuous variables. Differences were considered significant at p < 0.05. 3. Results Fig. 2. Coronal computed tomographic image after 1 week.

indicated downward movement at the buccal cusp of the right first molar. For the amount of impaction on the left, a positive value indicated impaction movement and a negative value indicated downward movement at the buccal cusp of the left first molar. Data were statistically analyzed using Dr. SPSSII (SPSS Japan Inc., Tokyo, Japan). A nonpaired t test or Scheffe test was used for comparison between groups. Then, stepwise regression analysis

Fig. 3. Coronal computed tomographic image after 1 year. The TCP remained in the left sinus after 1 year (red arrow).

3.1. Clinical findings None of the patients had severe rhinosinus symptoms preoperatively. After 1 week, all patients had nasal and sinus symptoms due to of the surgical invasion. One patient had mild stuffy nose symptoms and maxillary sinusitis at 1 year postoperatively. 3.2. Statistical results In the comparison of the rate of intact sinus area, there were significant differences between each period (preoperatively vs after 1 week postoperatively: p < 0.0001, preoperatively vs after 1 year: p ¼ 0.0149, after 1 week vs after 1 year: p < 0.0001) (Fig. 5). In the comparison of the rate of intact sinus area between men and women, there were significant differences preoperatively (p ¼ 0.0033) and after 1 week postoperatively (p ¼ 0.0072). However, there was no significant difference after 1 year. In the comparison of the rate of intact sinus area between Angle classes II and III and between symmetry and asymmetry, there were no significant differences. In the comparison of the rate of intact sinus area between uHA/ PLLA and PLLA, there were significant differences preoperatively

Fig. 5. Mean and standard deviation of the ratio of intact sinus area.

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Table 1 Results of comparisons between two group divisions. Number

Pre-operation Mean

Gender Angle class Asymmetry Fixation material Bone alternative material Pterygoid plate treatment a

Men Women II III Yes No uHA/PLLA PLLA Yes No Yes No

42 100 52 90 66 76 112 30 102 40 60 82

0.909 0.973 0.970 0.944 0.954 0.953 0.943 0.992 0.953 0.955 0.924 0.975

SD 0.174 0.081 0.084 0.135 0.091 0.141 0.131 0.042 0.132 0.082 0.153 0.083

After 1 week p value 0.0033

a

0.2166 0.9862 0.0454a 0.9120 0.0190a

Mean 0.399 0.526 0.503 0.480 0.482 0.494 0.494 0.466 0.498 0.463 0.460 0.509

SD 0.281 0.241 0.250 0.265 0.246 0.272 0.266 0.234 0.276 0.211 0.272 0.249

After 1 year p value

Mean

SD

p value

a

0.895 0.918 0.907 0.914 0.918 0.906 0.924 0.865 0.933 0.856 0.915 0.909

0.189 0.187 0.214 0.170 0.169 0.202 0.158 0.269 0.142 0.264 0.167 0.202

0.4976

0.0072 0.6057 0.7817 0.5919 0.4617 0.2703

0.8329 0.7023 0.1282 0.0282a 0.8544

Indicates a significant difference at p < 0.05.

(p ¼ 0.0454). However, there were no significant differences after 1 week and after 1 year. In the comparison of the rate of intact sinus area between treatment and nontreatment of the pterygoid plate, there were no significant differences. In the comparison of the rate of intact sinus area between use and non-use of bone alternative material (a-TCP), there were no significant differences preoperatively and after 1 week. However, there was significantly difference after 1 year (p ¼ 0.0282) (Table 1). The mean and standard deviation of the continuous variables used for the stepwise regression are shown in Table 2. For the stepwise regression analysis to predict the rate of intact sinus area after 1 week, age, the amount of anterio-posterior movement and the preoperative rate of intact sinus area were the variables selected that showed a significant difference (p < 0.0001) (Table 3). However, no variable could be selected in the analysis to predict the rate of intact sinus area after 1 year.

4. Discussion Maxillary sinusitis is one of the complications of Le Fort I osteotomy, as reported in previous studies (Panula et al., 2001; Pereira-Filho et al., 2011). However, the incidence of postoperative sinusitis after Le Fort I osteotomy is reported to be low. Pereira-Filho et al. (2011) reported an incidence of 4.76% for maxillary sinusitis as a postoperative complication. Nocini et al. (2016) reported that 1.6 % of the study sample had moderate to severe and 15.6 % had mild to moderate sinusitis symptoms postoperatively. They used the LundeMackay rhinologic staging scale to assess paranasal sinus abnormalities visible on CT (Sharp et al., 1999; Basu et al., 2005), and the Sino-Nasal Outcome 20-item Test (SNOT-20) (Lachanas et al., 2012) to assess rhinosinusitis issues. However, they were not used in this study, because no severe symptoms were found preoperatively and after 1 year. Nocini et al.

Table 2 Mean and standard deviation for each variable.

Age Operation time (min) Bleeding amount (ml) Anterio-posterior movement amount (mm) Lateral movement amount (mm) Impaction amount of anterior site (mm) Impaction amount of right molar site (mm) Impaction amount of left amount (mm)

Mean

Standard deviation

27.4 174.5 181.9 0.6 0.2 2.5 3.2 2.4

9.3 35.1 135.8 1.8 1.3 2.1 3.0 2.9

(2016) also showed that there was a significant difference between the pre- and postoperative volumes of the sinus. Although the condition of the sinus postoperatively is very important, no report has evaluated quantitatively the effect of various fixation materials on the maxillary sinus. It was very difficult to evaluate sinus conditions including postoperative hematoma or hypertrophy of the sinus membrane three-dimensionally. Therefore, the two-dimensional image of the coronal plane was used to measure the inner surface of the sinus bone and to examine soft tissue for symptoms including hematoma or hypertrophy of the sinus membrane. When the rate of intact sinus area (the inside air area/the maxillary sinus bony area) was 1, there was no hematoma or hypertrophy of the sinus membrane, and sinus was intact in this study. Results of this study showed that sinusitis including retention of hematoma and hypertrophy of the sinus membrane occurred immediately after surgery and decreased after 1 year. However, the rate of intact sinus area after 1 year did not reach the preoperative level statistically. In the simple two-group comparison, women were more frequent than men in regard to the incidence of sinusitis at 1 week pre- and postoperatively, but there was no difference in gender after 1 year. This might due to slight inflammation of the sinus that persisted in men after 1 year. The results of the Angle classification with and without asymmetry suggested that preoperative diagnosis was not related to the postoperative sinus condition. Fixorb®-MX, bioabsorbable ultrahigh-strength PLLA developed for internal fixation of fractures, was fabricated by a drawing technique developed by Matsusue et al. (1991, 1992). Furthermore, resorbable bone fixation devices (Super-FIXSORB®-MX. Takiron Co. Ltd, Osaka) have been developed for use in orthopedic or craniofacial, oral and maxillofacial or plastic and reconstructive surgeries (Shikinami and Okuno, 1999, 2001; Shikinami and Matsusue Nakamura, 2005). When the stability after Le Fort I osteotomy was evaluated, the results suggested that maxillary stability with satisfactory results could be obtained in the u-HA/PLLA, PLLA plate and titanium plate groups, even though there was a slight difference between the u-HA/PLLA plate system and PLLA plate system in Le Fort I osteotomy (Ueki et al., 2012). From the results of this study, the selection of uHA/PLLA or PLLA plate was not related to the postoperative sinus condition. In Le Fort I osteotomy, incomplete ossification of osteosynthesis is one of the major problems (Proffit et al., 2003). The line of osteosynthesis would involve a fibrous tissue rather than osseous tissue. In this instance, resistance to relapse would be via this fibrous tissue and the initial plate and screw rather than a robust osseous tissue (Holmes et al., 1988; Proffit et al., 2003). Although

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Table 3 Results of the stepwise regression analysis to predict the rate of intact sinus area.

Regression analysis Residual Total

Degree of freedom

Sum of squares

Mean square

F-value

p-value

3 138 141

1.716 7.753 9.469

0.572 0.056

10.18

<0.0001

Intercept Age Anterio-posterior movement amount Preoperative rate of air area

Coefficient

Standard error

Standard coefficient

Exceptional F-value

0.161 0.008 0.024 0.475

0.166 0.002 0.011 0.168

0.161 0.276 0.164 0.219

0.939 12.184 4.333 7.977

Rejected valuables

Partial correlation coefficient

Application F-value

Operation time Bleeding amount Lateral movement amount Impaction amount of anterior site Impaction amount of right molar site Impaction amount of left amount

0.065 0.095 0.118 0.045 0.085 0.059

0.584 1.237 1.942 0.274 0.998 0.472

bone contact between segments could be established in the maxillary impaction cases intraoperatively, there were cases in which complete bone healing could not be achieved after 1 year. The previous study suggested that thin bone at the edge along the osteotomy line could be resorbed after 1 year postsurgery (Ueki et al., 2013). To obtain long-term stability, self-setting a-tricalcium phosphate (Biopex®; Pentax Co, Tokyo, Japan) has also been a very useful bone alternative material (Monma et al., 1988; Ueki et al., 2013). Monma et al. (1988) originally developed a selfsetting cement-type calcium phosphate material consisting of aTCP, dicalcium phosphate dibasic (DCPD), and tetracalcium phosphate monoxide (TeCP). According to their extensive studies, this cement-type material could be refined, demonstrating better biocompatibility and direct integration with bone without any participation of peripheral soft tissue (Kurashina et al., 1997a,b; Yamamoto et al., 1998; Yuan et al., 2000). As it is free, over time, from infiltration of residual monomers of methacrylate resin, which has long been used for orthopedic treatment, this selfsetting cement came to be rapidly targeted for clinical use in Japan. In a previous study on maxillary stability after Le Fort I osteotomy with self-setting a-TCP and the uHA/PLLA plate, the results showed that stability did not depend on the use of it (Ueki et al., 2013). Furthermore, the results of this study suggest that the use of bone alternative material significantly affected sinus conditions after 1 year. Self-setting a-TCP was used at the lateral and anterior sites of the osteotomy line on the assumption that it would peel off from the maxillary bone and remain in the sinus after surgery. This might have induced inflammation in the sinus after 1 year, even though the symptom was not severe. The presence of remnant Biopex® after 1 year also suggested that resorption of the Biopex® was comparatively slow. Therefore, we surgeons should be careful when using self-setting materials so that they do not fall into the sinus. To prevent this, an adequate amount of the material and site at the osteotomy gap should selected and complete setting of the material confirmed intraoperatively. To remove the interference between the posterior site of the maxillary segment and the anterior site of the pterygoid plate, pterygoid plate treatment was performed safely using an ultrasonic bone curette as shown in the previous study (Ueki et al., 2004). This study suggested the treatment was not related to the postoperative sinus condition. In this study, age, amount of anterio-posterior movement, and preoperative rate of intact sinus area were selected as variables for the stepwise regression analysis that was performed to predict the

rate of intact sinus area after 1 week. However, no variables could be selected for the analysis to predict the rate of intact sinus area after 1 year. These results suggested that older age, backward movement of the maxillary segment, and preoperative sinusitis including hypertrophy of the sinus membrane should be considered closely before, during, and after surgery, to prevent sinusitis including hematoma and hypertrophy of the sinus membrane immediately after surgery, even though the sinus condition after 1 year could not be predicted. 5. Conclusion The study suggests that the bone alternative material a-TCP might be a cause of inflammation in the sinus after 1 year. In addition, older age, backward movement of the maxillary segment, and preoperative sinusitis including hypertrophy of the sinus membrane should be considered closely in Le Fort I osteotomy. Sources of support in the form of grants None. Conflict of interest None declared. References Araujo A, Schendel SA, Wolford LM, Epker BN: Total maxillary advancement with and without bone grafting. J Oral Surg 36: 849e858, 1978 Basu S, Georgalas C, Kumar BN, Desai S: Correlation between symptoms and radiological findings in patients with chronic rhinosinusitis: an evaluation study using the Sinonasal Assessment Questionnaire and Lund-Mackay grading system. Eur Arch Otorhinolaryngol 262: 751e754, 2005 Bloomquist DS: Long-term results of subperiosteal implants combined with cancelleous bone graft. J Oral Maxillofac Surg 40: 348e352, 1982 Bloomquist DS: The posterior ilium as a donor site for maxillo-facial bone grafting. J Maxillofac Surg 8: 60e64, 1980 Burton DM, Berarducci JP, Scheffer RB: Proplast grafting: a new method for stabilization of maxillary advancements. J Oral Surg 50: 387e389, 1980 Dahlberg G: Statistical methods for medical and biological students. London: George Allen and Unwin, 122e132, 1940 Epker BN, Friedlaender NC, Wolford LM, West RA: The use of freeze-dried bone in middle-third face advancements. J Oral Surg 42: 278e289, 1976 Holmes RE, Wardrop RW, Wolford LM: Hydroxyapatite as a bone graft substitute in orthognathic surgery: histologic and histometric findings. J Oral Maxillofac Surg 46: 661e671, 1988 Kent JN, Zinde MF, Kay JF, Jarcho M: Hydroxyapatite blocks and particles as bone graft substitutes in orthognathic and reconstructive surgery. J Oral Maxillofac Surg 44: 597e605, 1986

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