Reliability of three-point fixation and orbital floor reconstruction based on changes in orbital volume measurements and enophthalmos in patients with zygomaticomaxillary complex fractures

doi:10.21203/rs.3.rs-2850862/v1

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Reliability of three-point fixation and orbital floor reconstruction based on changes in orbital volume measurements and enophthalmos in patients with zygomaticomaxillary complex fractures

https://doi.org/10.21203/rs.3.rs-2850862/v1

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This retrospective cohort study aimed to calculate the amount of enophthalmos and volume difference between the repaired and intact orbits after 3-point fixation of unilateral zygomatic complex fractures (ZMCFs) with the reconstruction of the orbital floor. It was conducted between 2015 and 2020. The orbital volume (OV) was measured by manual tracing methods on pre- and postoperative CT scans. The OV were categorized into OV_Intact/pre, OV_Intact/post, OV_Fractured, and OV_Repaired. The OV_Intact/pre, OV_Intact/post, OV_Fractured were used as control groups. Outcome variables were the mean of the OV, volume difference between repaired and intact orbits, correction rate, and measurements of enophthalmos. The results are considered significant with p-values < .05. The study included 63 patients, and the results showed that the study’s treatment protocol significantly changed the OV_Fractured from 26.10 ± 1.14 to 21.93 ± 1.25 cc. The volume difference between intact and repaired orbits was ranged from 0.34 ± 0.03 to 0.35 ± 0.02 cc with 98.40% correction rate. Also, the mean of enophthalmos was reduced from 2.48 ± 0.41 to 0.47 ± 0.42 mm. So, it could be concluded that after 3-point fixation of ZMCFs with the reconstruction of the orbital floors, the OV is significantly restored with a minimal volume difference between both orbits about 0.34 ± 0.03 cc and 0.47 ± 0.42 mm enophthalmos.

Zygomatic Complex Fractures

Three-point Fixation

Orbital Floor Reconstruction

Orbital Volume

Enophthalmos

Midface Fractures

ZMCFs are categorized as midface fractures and described as fractures involving the zygomatic, maxillary, and orbital tissues. They are the second most frequent maxillofacial fractures, accounting for roughly 13% of all craniofacial fractures and 20.5% of all fractures in Saudi Arabia.^1,2 ZMCFs compromise orbital structures due to zygomatic bone displacement, which frequently occurs in the lateral, medial, and/or posterior direction depending on the vector of traumatic forces. The lateral displacement of zygoma along its vertical axis increases the OV.² Any changes in the OV, shape, and integrity result in major functional and clinical problems, such as diplopia, enophthalmos, and muscle entrapments. Therefore, accurate treatment of ZMCFs and restoration of the OV are important to prevent complications and achieve proper function, esthetic, and long-term outcomes.^3,4

Despite the large amount of literature describing the management of ZMCFs, there is still no conclusive data establishing the accuracy of their management.^5,6 To the best of our knowledge, the analysis of OVMs following the open reduction and rigid fixation (ORF) of ZMCFs is still underreported regarding the amount of the volume difference between the repaired and intact orbits. Therefore, this study was conducted to determine to what extent the 3-point fixation of unilateral ZMCFs with orbital floor reconstruction is able to minimize the amount of the volume difference and enophthalmos between repaired and intact orbits. Besides, the study aimed to report 10 years’ experience with this treatment option.

Study Design

A retrospective cohort study was conducted at Al Zahraa Educational Hospital, Al Azhar University, Egypt from February 2015 to December 2020. The Dental Ethical Committee, College of Dentistry, Qassim University, Saudi Arabia, approved the study on 19/4/2020 with a reference code “EA/F-2020-3009”. This study was carried out in accordance with the code of ethics of the World Medical Association Declaration of Helsinki, and patients or the next of kin of the patients were informed and gave written informed consent. The Ethical Reviewer Board of the hospital agreed to access the hospital's data base. The inclusion criteria were: Ages over 18 years, unilateral displaced ZMCFs with blow-out fractures of the orbital floor, ZMCFs fractures fixed with a titanium miniplate/mesh osteosynthesis, CT scans obtained one week after trauma and four weeks after surgery, and cases treated between 2005 and 2015. The cases were excluded if there were: missing pre- and post-operative CT scans, artifacts on CT images, medial or superior orbital wall fractures, traumatic telecanthus, and correction surgeries for ZMCFs or preinjury orbital abnormalities.

Study Variables

The primary predictable variable was the treatment protocol, which involved 3-point fixation of ZMCFs with orbital floor reconstruction. The primary outcome variables were: 1) the volume difference between the repaired and intact orbits, and 2) the percentage of changes in the OVMs of the repaired orbit before and after the treatment. The changes in the measurements of enophthalmos before and after management were also recorded as an additional record.

Data Collection

The demographic data, history and cause of the trauma, signs and symptoms before surgeries, timing of surgeries, and clinical outcomes after surgery were recorded. The non-contrast-enhanced CT scans were obtained via the same machine (Siemens, Erlangen, Germany), and the cuts were taken with 0.3 mm thickness at 180 mAs and 100 kVp. Each CT scans consisted of 25–30 consecutive sections through orbits, and at 0 to 10° from the canthomeatal line, the axial views were obtained. The patients fixed their gaze to a point in the overhead gantry during scanning. The three-dimensional CT (3DCT) images were examined to confirm the diagnosis of the ZMCFs. All the bony windows axial, coronal, and sagittal views were reviewed to measure the OV. All the measurements were performed by two independent investigators, and the average of their readings were documented as final records. The OV of both fractured and unfractured sides in the pre- and postoperative CT scans. Accordingly, the OVMs of intact orbits were categorized into preoperative (OV_Intact/pre) and postoperative records (OV_Intact/post). The OVMs of fractured orbits were classified into: the preoperative measurements (OV_Fractured) and postoperative records (OV_Repaired). The OV_Intact/pre, OV_Intact/post, and OV_Fractured were set as control groups.

The manual tracing method was used to measure the OV. This method was based on the summation of the manually delineated areas of the orbits in the CT scans. The CT DICOM file was imported to Mimic software version 9 (Materialase, Leuven, Belgium) which was installed into a standard personal computer running windows 8. The CT scans were displayed as axial, coronal and, sagittal images. The investigators manually delineated the bony boundaries of the orbit on the consecutive slices of the CT views on bone density threshold (Fig. 1). In the axial view, each investigator proceeded section by section and situated it in the sagittal and coronal images. At the level of the greatest anteroposterior length of the orbit, by using a cursor, a straight line was drawn along the most anterior point of the opening of the optic canal, superior orbital fissure, and inferior orbital fissure. This was performed to exclude the orbital foramina and fissures by covering them with the drawn line. The anterior orbital boundaries were defined by a straight line connecting the medial and lateral orbital rims. The highlighted tracing orbit that appeared was verified, and then the OV was measured in cubic centimeters (cc) by using the built-in measuring tool of the software. Also, the correction rate of the OV on the fractured side was calculated by the following equation:

\(\frac{\text{O}\text{V} \text{I}\text{n}\text{t}\text{a}\text{c}\text{t}/\text{p}\text{r}\text{e} \text{O}\text{R} \text{O}\text{V}\text{I}\text{n}\text{t}\text{a}\text{c}\text{t}/\text{p}\text{o}\text{s}\text{t}}{\text{O}\text{V} \text{R}\text{e}\text{p}\text{a}\text{i}\text{r}\text{e}\text{d}}\times 100\)

Clinical Examination

The pre- and postoperative clinical examinations of the ZMCFs were performed to the eyes and face by an expert ophthalmologist and maxillofacial surgeon, respectively. The ophthalmic examination was performed for the globe and vision. The clinical examination included a cosmetic and functional assessment. The cosmetic assessment was performed for the facial asymmetry due to either soft tissue injuries (edema/ emphysema) or displaced zygoma (depression/ projection/ widening), discoloration (subconjunctival hemorrhage/ periorbital ecchymosis or hematoma), altered morphology or position of the globe (enophthalmos/exophthalmos, hypoglobus/hypergloubs), and altered morphology or position of the upper eyelid (increased/decreased sclera show). The functional assessment was performed for the restricted mouth opening, malocclusion, neurological deficits (infraorbital, zygomaticofacial, and zygomaticotemporal nerves), restricted eye movements, vision (diplopia, loss of vision, visual acuity, fundus examination), and retrobulbar hemorrhage. The diplopia was recorded if there was a 30-degree field of vision, or there was an affected frontward gaze which compromises the patient’s daily activities. The Hertel exophthalmometer was used to measure the enophthalmos, and the extraocular muscle function test was performed to identify restrictions in the eye movements.

Surgical Procedures

All patients were treated under general anesthesia with an endotracheal intubation. The fractures were approached via subciliary incisions to access inferior orbital rims and orbital floors, maxillary vestibular approaches to fix maxillary-zygomatic buttresses, and lateral lower eyebrow incisions to approach zygomatico-frontal sutures. The fracture sites were exposed via subperiosteal reflection with a care to avoid injury of important orbital structures. The care was also taken to maintain the incomplete greenstick fractures in the floor of the orbit without damaging the mucoperiosteum. The entrapment of the inferior rectus muscle or orbital fat in the floor of the orbit was released. All bony segments were reduced to their anatomical positions by raising the displaced bony fragments with bony hooks or periosteal elevators. To detect the zygomatic projection on both sides, the reduction of zygoma was examined from behind the patient. The fractures were fixed via the concept of the 3-point fixation method by using 2.0 mm miniplates at inferior orbital rims, zygomatico-frontal sutures, and zygomatic buttresses.

At our department, the indications of the orbital floor reconstruction are a restriction of the eye movements, soft tissue entrapment, persistent diplopia, large bony defect more than one-half of the length of the floor as showed in the CT scans, and an enophthalmos more than 2 mm. The orbital floors were reconstructed via preformed orbital floor titanium plates with cautions to avoid injury of the inferior orbital nerve during fixation of plates. In this process, the forced duction test was performed to detect any restrictions in the eye movements after plates fixation. Besides, the horizontal position and the degree of the eyes protrusion in both eyes were compared for any asymmetry. The periosteal incisions were sutured via 3 − 0 vicryl interrupted sutures. The skin incisions sutured via subcuticular sutures with 6 − 0 prolene suture materials which were removed after five days. Whereas the vestibular incisions were repositioned through 3 − 0 vicryl running sutures.

Follow-up:

During the first month after surgery, the patients were weekly observed, then monthly for three months. All the patients were followed for healing of the surgical wounds. All the above-mentioned cosmetic and functional assessments for the face and eyes were also performed postoperatively to determine the postoperative changes.

Statistical Analysis:

Shapiro- Wilk test was used to assess normality distribution. The descriptive results were expressed as a percent and mean ± standard deviation for the normally distributed data at a 95% confident level. SPSS software version 25.0 was used to analyze the changes in the OVMs difference using a two-tailed independent t-test. P-values < .05 were considered significant.

Sixty-three out of 230 files met the study’s inclusion criteria who their demographic data were summarized in Table 1. The male patients were predominating with a male to female ratio of 2.15: 1. The patients’ age ranged from 20 to 46 years with a mean age of 30.03 ± 6.5 years. Road traffic accidents were the main cause of ZMCFs, followed by fallen from the first or second floor, and then sports injuries. The left side constituted 61.9% of the patients. The maximum OV measurement of the intact orbits was 23.32 cc in the postoperative CT scans, whereas that of the fractured orbits was 28.66 cc as shown in Table 2.

Table 1

Summary of patients’ demographic data
Parameter	Data (n = 63)
Age in years: Mean ± SD SE Range	30.03 ± 6.5 1.60 20–46
Gender (% and N): Female Male	31.7% (20) 68.3% (43)
Cause (% and N): Road Traffic Accidents Fall Sports Injuries	60.3% (38) 19.1% (12) 20.6% (13)
Side of the fracture, (%) Right Left	38.1% (24) 61.9% (39)
Sins and Symptomes (% and N): Diplopia Limitation of EOM Infraorbital nerve affection Periorbital hematoma Subconjunctival hemorrhage Visual Defect	77.8% (49) 52.4% (33) 39.7% (25) 90.5% (57) 96.8% (61) 6.4% (4)
Radiographic findings of orbital floor fractures: Displaced orbital floor fracture Trap-door orbital fractures with muscle entrapment	76.2% (48) 23.8% (15)
Timing of Surgery in days: Mean ± SD SE Range	13.21 ± 1.55 0.31 10–17
n: Patients Number; SD: Standard Deviation; SE: Margin of Error at Confidence Level 95%; EOM: Extraocular Muscle Movement.

Table 2

The measurements of control groups
Parameters	Mean ± SD	SE	Range
OV _Intact/pre	21.58 ± 1.14 cc	0.28	19.30- 23.31 cc
OV _Intact/post	21.59 ± 1.13 cc	0.27	19.31–23.32 cc
OV _Fractured	26.10 ± 1.14 cc	0.28	23.28–28.66 cc
OV: Orbital Volume; SD: Standard Deviation; SE: Margin of Error at confidence level 95%; CC: Cubic Centimeter.

The impact of trauma on the fractured orbits was highly significant, where it causes a mean volume difference of 4.52 ± 0.71 and 4.51 ± 0.73 cc between the intact and fractured orbits on the pre and postoperative CT scans, respectively (Table 3). The percent of the increase from OV of the intact orbits to the fractured orbits was highly significant, where all p- values were less than .00001. It constituted 20.95% on the preoperative CT scans and 20.89% on the postoperative images. As shown in Table 3, trauma led to 18.96% volume difference between both orbits. Table 4 compared the OVMs of the intact orbits on the pre- and postoperative CT scans. There was a difference between OV_Intact/pre and OV_Intact/post with a mean of 0.01 ± 0.3 cc. The OV_Intact/post was larger than that of the OV_Intact/pre by a percent of 0.046 increase, but this difference was statistically insignificant (p- value = .093).

Table 3

Effect of trauma on the fractured orbits as compared to the intact orbits on pre- and postoperative CT scans
Parameter	Mean ± SD	Volume difference Mean ± SD	Percentage of Volume Difference	Percentage of Increase	t- value	P-value
OV^* _Intact/pre:	21.58 ± 1.14 cc	4.52 ± 0.71 cc	18.96%	20.95%	-27.01	< .00001
OV^* _Fractured:	26.10 ± 1.14 cc	4.52 ± 0.71 cc	18.96%	20.95%	-27.01	< .00001
OV^# _Intact/post:	21.59 ± 1.13 cc	4.51 ± 0.73 cc	18.91%	20.89%	-27.14	< .00001
OV^* _Fractured:	26.10 ± 1.14 cc	4.51 ± 0.73 cc	18.91%	20.89%	-27.14	< .00001
OV: Orbital Volume; SD: Standard Deviation; CC: Cubic Centimeters; : The OV are measured on the preoperative CT scans; #: The OV are measured on the postoperative CT scans.*

Table 4

Statistical analysis of the changes in the orbital volume of both fractured and unfractured sides before and after treatments
Parameter	Measurements	Volume difference Mean ± SD	Percentage of Volume Difference	Percentage of Change	t- value	P- value
OV^* _Intact/pre: Mean ± SD SE Range	21.58 ± 1.14 cc 0.28 19.30- 23.31 cc	0.01 ± 0.3 cc	0.04633%	0.04632%^{^}	-1.36	.093
OV^# _Intact/post Mean ± SD SE Range	21.59 ± 1.13 cc 0.28 19.31–23.32 cc	0.01 ± 0.3 cc	0.04633%	0.04632%^{^}	-1.36	.093
OV^* _Fractured: Mean ± SD SE Range	26.10 ± 1.14 cc 0.28 23.28–28.66 cc	4.17 ± 0.08 cc	17.37%	15.98%^!	19.40	< .00001
OV^# _Repaired: Mean ± SD SE Range	21.93 ± 1.25 cc 0.31 19.90- 24.87 cc	4.17 ± 0.08 cc	17.37%	15.98%^!	19.40	< .00001
OV: Orbital Volume; SD: Standard Deviation; SE: Margin of Error at confidence level 95%; CC: Cubic Centimeter; *: The OV are measured on the preoperative CT scans; #: The OV are measured on the postoperative CT scans; ^: Percentage of Increase; !: Percentage of Decrease.

The postoperative surgical results showed that in all, but 16 patients, all the ZMCFs and surgical wounds healed without complications. In those 16 patients, the following complications were reported as follow: Firstly, in eight cases the lower eyelid ectropion and sclera show were developed and both of them resolved within 6 months. Secondly, five cases developed infraorbital paresthesia after surgery, and, in two of them, the paresthesia was also recorded preoperatively as a result of the trauma which did not subside. Finally, the last three patients developed a mild postoperative infection with a wound dehiscence and plates’ exposure at the intraoral vestibular incisions. Nevertheless, after maintaining a proper oral hygiene and administrating antibiotics, the soft tissue healing occurred eventually and all exposed plates were recovered with soft tissues within three months. The preoperative diplopia and limitations of eye movements also immediately subsided after surgeries in all patients.

Regarding the OVMs, as a general, the postoperative results showed that the study’s treatment protocol significantly restored the OV, where all p- values were less than .05. It reduced the OV_Fractured by 4.17 ± 0.08 cc, and changed the OVMs from 26.10 ± 1.14 cc (OV_Fractured) to 21.93 ± 1.25 cc (OV_Repaired) as represented in Table 4. The comparative analysis between the OV_Repaired and OV_Intact/post showed that the study’s treatment protocol changed the volume difference between both orbits from 4.51 ± 0.73 cc (Table 3) to 0.34 ± 0.03 cc with a percent volume difference 1.56 and a correction rate of 98.40% (Table 5). When using the records of the OV_intact/pre to analyze the difference between the repaired and intact orbits, the results were 0.35 ± 0.02 cc, 1.61, and 98.40 volume difference, percent of volume difference, and correction rate, respectively. There was no significant difference between the pre- and postoperative records of the intact orbits.

Table 5

Impact of the study’ treatment protocol on the repaired orbits as compared to the pre and postoperative intact orbits
Parameter	Mean ± SD	Volume difference Mean ± SD	Percentage of Volume Difference	Percentage of Increase	Correction rate	t- value	P-value
OV^* _Intact/post:	21.59 ± 1.13 cc	0.34 ± 0.03 cc	1.56%^~	1.58%	98.40%	-4.28	.00002
OV^* _Repaired:	21.93 ± 1.25 cc	0.34 ± 0.03 cc	1.56%^~	1.58%	98.40%	-4.28	.00002
OV^# _Intact/pre:	21.58 ± 1.14 cc	0.35 ± 0.02 cc	1.61%^~	1.62%	98.40%	-6.27	< .00001
OV^* _Repaired:	21.93 ± 1.25 cc	0.35 ± 0.02 cc	1.61%^~	1.62%	98.40%	-6.27	< .00001
OV: Orbital Volume; SD: Standard Deviation; #: The OV are measured on the preoperative CT scans; *: The OV are measured on the postoperative CT scans; ~ : The amount of the difference is within the normal difference between both orbits in the same person (0–8%).

Regarding the enophthalmos, the study’s treatment protocol was also significantly successful in the management od enophthalmos. The mean of the preoperative enophthalmos was ranged from 2 mm to 3 mm, and postoperatively its mean was ranged between 0 mm and 1.5 mm as shown in Table 6. The enophthalmos was completely disappeared in the majority of the patients (80.95%), and the percent of difference between its pre- and postoperative measurements was 136.27% which was changed into 81.048% after the treatment with a p-value less than .00001.

Table 6

Changes in the measurements of enophthalmos before and after surgeries
Parameter*	Preoperative	Postoperative	Percent of Difference	Percent of Decrease	t- value	P-value
Mean ± SD SE Range	2.48 ± 0.41 mm 0.102 2–3 mm	0.47 ± 0.42 mm 0.103 0- 1.5 mm	136.27%	81.048%	26.97	< .00001
Value Frequency in mm (n and %): 0 0.5 1 1.5 2 2.5 3	- - - - 23 (36.50%) 20 (31.75%) 20 (31.75%)	51 (80.95%) 7 (11.11%) 3 (4.76%) 2 (3.18%) - -
*: Measured by Hertel Exophthalmometer; mm: Millimeters; SD: Standard Deviation; SE: Margin of Error at confidence level 95%; n: Patients’ number (total = 63 subjects).

The anatomical complexity of ZMCFs constitutes a big challenge to be accurately repaired, and still there is no consensus on their management.^7,8 There are different treatment protocols for their management. Whatever the chosen one, its aim has to restore the OV for optimum postoperative outcomes. Therefore, this study was conducted to evaluate the changes in the OVMs before and after the 3-point fixation of ZMCFs and to determine to what extent this treatment protocol is able to re-establish the OV of the fractured orbits as compared to the intact orbits on both pre- and postoperative CT scans.

There are several methods which have been documented to measure the OV.^9,10 In this study, the manual tracing method was used according to the study of Sharma et al.² The results showed that this method has advantages of low cost, easy, available, and no need for technical expertise. Also, it does not require additional procedures such as those steps which are needed for the 3D modeling.¹⁰ Despite that, it is a time-consuming method, where it needs about 20 min to trace and measure the OV of one orbit. Furthermore, the OV on axial scans differs according to the anterior limit of the orbit as reported by others.⁹

Many authors have published the average of the normal orbital volume in different population. The study’s results revealed that the OVMs of the intact orbits in both pre- and postoperative CT scans are in commensurate with others ^2,11, but differ with some studies.^3,10 The mean OV_Intact/pre was 21.58 ± 1.14 cc, whereas that of the OV_Intact/post was 21.59 ± 1.13 cc. There was a mean volume difference of 0.01 ± 0.03 cc between them. Although this difference is statistically insignificant, this difference could be due to the manual tracing method which has been documented as an investigator dependent procedure as reported by many authors.^12,13 Thus, for the reliability of the study’s results, the records of the OV_Repaired were compared to those of the intact orbits in the pre- and postoperative CT scans. Trauma, in our study, led to a significant volume difference between both orbits. The OV_Fractured was larger than the OV_Intact/pre and OV_Intact/post by a mean of 4.52 ± 0.71 cc (20.95% amount of increase) and 4.51 ± 0.73 cc (20.89 percent of increase), respectively. Those findings correspond to the findings of Shadarmashan et al.,⁹ who also reported a significant difference between both orbits after trauma. However, other authors reported that the trauma only increased the mean of OVMs by 1.97 cc.¹⁴ This difference in the amount of change between this study and other studies could be owed to the cause of trauma in our study, where all of its cases were subjected to high energy trauma that led to severe displacement of ZMCFs.

The study’s treatment protocol led to 98.40% correction rate and minimized the volume difference between the repaired and intact orbits to 1.56% (as compared to the VO_Intact/post) or 1.61% (when compared to the VO_Intact/pre). Although the OVMs of the repaired orbits are still larger than both records of the intact orbits, this volume difference is within the margin of the normal difference between left and right orbits in the same person, where Glenn Forbes et al.,¹⁵ found that there is a volume difference between both orbits in the same person, and this difference varies from 0 to 8%. Also, Sentucq et al.,⁵ and Andrades et al.,¹⁶ reported the same findings in their studies. This volume difference could be due to many factors, such as anatomical variations, quality of CT scans, thickness of the slice, type of the cut, and methods which are used to determine orbital boundaries, particularly anterior boundaries. Up to date problems associated with those factors are not solved.^3,17−20 The authors believe that this volume difference between the repaired and intact orbits could be also owed to the manual tracing method which was used for determining the orbital boundaries. It was reported that among all the documented methods, the highest variability is recorded with the manual tracing method.^13,12

Enophthalmos is also an important indicator for the validity of the surgical intervention for ZMCFs. It occurs due to the displacement of the orbital contents into the paranasal sinuses, increased OV, atrophy of the orbital fats, or inadequate fixation of the orbital wall fractures.¹⁴ In this study, the trauma led to 2 mm to 3 mm enophthalmos which was corrected to 0 mm in the most of the study’s cases (51 out of 63 patients). This also indicates the validity of the study’s treatment protocol. In the rest of the cases, still there is enophthalmos which ranged between 0.5 mm and 1.5 mm. Nevertheless, the enophthalmos was clinically invisible in all of them. The presence of the postoperative enophthalmos may be owed to the delay in the surgical intervention, where all of the study’s patients were treated within 15 to 17 days after trauma due to a subsequent preorbital edema. It has been documented that if the surgical management of ZMCFs is delayed until the edema is subsided, it is too difficult to treat enophthalmos due to the atrophy and fibrosis of the periorbital tissues.¹⁹

The clinical significance of this study is that it analyzed to what extent the 3-point fixation of ZMCFs with the reconstruction of the orbital floor is able to reduce the volume difference between the repaired and intact orbits. Up to our knowledge, this point is not previously investigated in literatures. Besides, it emphasizes the efficacy of this treatment protocol that omits the need for the use of more aggressive procedures like the 4-point fixation of ZMCFs. It also adds an additional record for reports that evaluate the use of the OVMs as an indicator for the treatment of ZMCFs. The study has many strength points, such as it is a single institutional study, the main surgeon was the same surgeon in all patients, and the study did not include multiple racial groups where all the included patients were Middle Eastern Arabian patients. All those factors eliminate the cofounding factors that might affect the study’ results. However, the study has some limitations as follow: the limited sample size, and the use of the manual tracing method which is observer depended procedures. Besides, it lacks the preferred comparative study’s design where it did not compare between different treatment options. Therefore, further studies with a larger sample size and different treatment options comparison are warranted.

With regard to the results of the study, it could be concluded that the 3-point fixation of the ZMCFs with the reconstruction of orbital floors is able to minimize the volume difference between the repaired and intact orbits to a mean of 0.34 ± 0.03 cc with a correction rate 98.40%. Furthermore, it led to volume difference between both orbits 1.56% which is within normal difference between left and right orbits in the same person. Moreover, the enophthalmos is significantly reduced to 0.47 ± 0.42 mm even in the cases with a delayed management. So, the study recommends the use of the 3-point fixation with the reconstruction of the orbital floor as a first choice for the treatment of ZMCFs and the use of the postoperative CT scans for the volume analysis of intact orbits.

Ethics approval and consent to participate

The Dental Ethical Committee, College of Dentistry, Qassim University, Saudi Arabia, approved the study on 19/4/2020 with a reference code “EA/F-2020-3009”. This study was carried out in accordance with the code of ethics of the World Medical Association Declaration of Helsinki, and patients or the next of kin of the patients were informed and gave written informed consent.

Consent for publication

Not applicable.

Availability of data and materials

The data used to support the findings of this study are available from the corresponding author upon reasonable request.

Competing interests

The authors declared that the study has no personal relationship with any people or organization that inappropriately affect the work.

Funding

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors

Authors Contributions

Alharbi GM and Khalifa GA conceived of the presented idea. Alharbi GM developed the theory and performed the computations.

Khalifa GA verified the analytical methods. Khalifa, GA encouraged Alharbi GM to investigate the management of the Zygomatic complex fractures via three-point fixation and orbital floor reconstruction and supervised the findings of this work. All authors discussed the results and contributed to the final manuscript.

Acknowledgements

We would like to express our sincere gratitude to our supervisor, Professor Susan Abd El-Hakim Hassan, for her valuable guidance and work during surgeries. Her expertise and insights were invaluable in shaping our research and helping us to overcome challenges.

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No competing interests reported.

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Reliability of three-point fixation and orbital floor reconstruction based on changes in orbital volume measurements and enophthalmos in patients with zygomaticomaxillary complex fractures

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