Journal of

Abstract
Introduction: Fractures of the nose and lower jaw are common injuries. Given that dentists may encounter these types of injuries, it is crucial to know this area. This study aims to evaluate the level of knowledge among general dentists and dental students from Zahedan on the diagnosis and initial management of mandibular fractures.
Methods: This cross-sectional study included 200 general dentists and final-year dental students who were conveniently selected and examined through a researcher-made questionnaire. To determine and select samples proportional to the population size in each stratum (dentists and students), the quota for each was determined. Then, to select samples in each stratum according to the inclusion criteria in an easy and accessible manner, sampling was conducted from each stratum. Data were analyzed using SPSS software (version 26), independent t-test, and Chi-square statistical test.
Results: The mean age of the students was 24.4±6.2 years, while the mean age of the dentists was 36.6±8.4 years. In terms of gender distribution, male students made up 46.2% of the participants, while female students comprised 53.8%. Among general dentists, 43.6% were male, and 66.4% were female. The average working experience in general dentists was 9.4±3.1 years. Of the participants, 139 (69.5%), 14 (7%), 20 (10%), 18 (9%), and 9 (5.5%) mentioned motor vehicle accidents, fights, sports injuries, falls, and iatrogenicity following surgery as the most common causes of mandibular fractures, respectively. The level of knowledge about fracture management and care was significantly related to job position (P=0.03) and work experience (P=0.04).
Conclusion: The level of knowledge among dental students and dentists regarding mandibular fractures, their diagnosis, and initial management is inadequate. Therefore, students and dentists should be trained in this field before graduation, and their training should be updated regularly.
Key words: Dental students, Dentists, Mandibular fractures

Introduction
Fractures involving the nose and lower jaw are frequently encountered injuries. While most nasal fractures can be managed without surgery, surgical treatment is often necessary for mandibular fractures due to the intricate anatomy and function of the jaw. The mandible, being a movable bone, is prone to multiple fractures, with a risk of contamination from normal oral bacteria. Additionally, adjacent teeth may be affected, and in some cases, mandibular fractures can lead to respiratory issues in the patient (1).
The mandible, nasal, and zygomatic bones are frequently fractured due to facial trauma from falls, fights, or car accidents. Patients with mandibular fractures should be evaluated for potential injuries to the cervical spine and brain (2).
Third molar surgery is a common facial surgery in the field of dentistry. However, it can be associated with various complications (3, 4). The most common complications following mandibular third molar surgery are nerve damage, dry socket, infection, bleeding, and pain. Less common complications include severe jaw stiffness, damage to the adjacent tooth, and accidental jaw fractures (5).
Facial fractures constitute approximately 15% of emergency visits in general. However, the occurrence rate of iatrogenic mandibular fractures resulting from mandibular third molar surgery has been reported to range from 46 to 75 per one hundred thousand cases (6, 7). Regarding gender distribution, research indicates that male patients over the age of 40 face a higher risk of mandibular fracture (8).
Identifying the symptoms and causes of mandibular fractures is essential. Patients often experience jaw pain, facial asymmetry, facial deformity, and difficulty swallowing. Other possible symptoms include misaligned teeth, limited jaw movement, jaw stiffness, or numbness in the lower lip (9).
Hence, during the physical examination, it is essential to assess the jaw and facial region for any signs of deformity, such as ecchymosis and edema (10). During an intra-oral examination, it is crucial to check for malocclusion, trismus, and facial asymmetry. Assessing the patient's occlusal status before surgery can be difficult, but dental records, if accessible, can be a helpful reference for fracture reduction (11).
Diagnosing mandibular fractures requires X-rays, including a series of images, a panoramic view, and a CT scan. The series of images includes views from the front, sides, and top, which help examine the jaw joint and its connecting area (12).
A panoramic X-ray is better for examining fractures in the front and body of the jaw. A CT scan is recommended if there are possible fractures in other facial bones. For patients who are unconscious and have missing teeth, a chest X-ray is needed to check for aspiration. Blood tests are usually not necessary, but in certain cases, basic tests, such as a complete blood count and INR, may be done for patients taking blood thinners (13).
In 2017, Pickrell et al. conducted a study on mandibular fractures in Texas, USA. They found that mandibular fractures are a significant part of maxillofacial injuries and their evaluation, diagnosis, and management remain challenging despite advances in imaging technology and fixation techniques. Proper surgical management can prevent complications, such as pain, malocclusion, and trismus. Open and closed surgical reduction techniques can be used based on the type and location of fractures (14).
Previous studies indicate that mandibular fractures are common in the jaw and face, often caused by road accidents. Cone beam computed tomography (CBCT) is the preferred method for diagnosing mandibular fractures. Panoramic radiography has a limitation of presenting fracture lesions separately (15).
In 2019, Hassanein et al. conducted a study in Saudi Arabia to evaluate the methods and results of mandibular fracture management, and in this study, 1,371 patients were studied. The results of this study showed that the most common cause of mandible fracture was road accidents and falling from a height. Also, in this study, more mandible fractures were observed in young people, and the most common treatment used for mandibular fractures was open surgery and internal fixation (16).
In their 2021 study "Mandibular Fractures: Diagnosis and Management," Panesar et al. from Washington, USA highlighted the need for accurate evaluation, diagnosis, and management of mandibular fractures to restore facial aesthetics and functionality. Understanding surgical anatomy, fracture fixation principles, and specific fracture characteristics in different patient populations can prevent such complications as malocclusion, non:union:, and paraesthesia (17).
Mandibular fractures are a common type of facial injury, often resulting from accidents, assaults, or falls. The ability to diagnose and treat these fractures effectively is essential for oral and maxillofacial surgeons and general dentists. Considering the aforementioned information and recognizing the significance of mandibular fractures, as well as the lack of comprehensive studies in this area within Zahedan, our study aims to investigate the level of knowledge among general dentists and final-year dental students in Zahedan during 2023. This group is often one of the first to evaluate patients with isolated lower jaw fractures, and they need to possess knowledge regarding the diagnosis and initial management of mandibular fractures. The findings of this study can be valuable in formulating strategies to enhance dentists' awareness and subsequently reduce the complications associated with such fractures.

Methods
The study protocol was approved by the Ethics Committee of Zahedan University of Medical Sciences (ethics code: IR.ZAMUS.REC.1402.288). This cross-sectional study included a total of 200 final-year dental students and general dentists. Data collection for this study involved interviews and the administration of questionnaires, using information forms and researcher-made questionnaires. The reliability and validity of the questionnaire about the diagnosis, treatment, care, and management of mandibular fractures were previously confirmed in a separate study in Iran (18). Minor modifications were made to the questionnaire, and its validity was assessed by evaluating the Content Validity Index (CVI) and Content Validity Ratio (CVR) with the input of six experts, resulting in 73% and 78%, respectively. Additionally, the questionnaire's reliability was established through its completion by 36 individuals from the research population, yielding a Cronbach's alpha value of 0.79.
Sample selection was carried out based on the population size within each group (dentists and students), with the allocation of proportional representation. Simple and accessible sampling methods were employed to select participants from each group according to predetermined criteria. Based on a previous study (18) indicating that only 16% of dentists demonstrated accurate knowledge regarding mandibular fractures, and considering a Type I error of 0.05 and a maximum acceptable difference of 0.05 (d=0.05), a minimum sample size of 200 individuals was determined using the following formula:

Participants were recruited if they met the following criteria: being a licensed general dentist or a final-year dental student, residing in Zahedan, and expressing a willingness to participate in the study. Individuals were excluded from the study if they were unwilling to complete the post-interview questionnaire.
Subsequently, the questionnaires and information forms were distributed to the research units either in person or online, and collected upon completion. To control for confounding variables, only individuals who expressed full willingness and had sufficient time to participate in the study were included, after receiving detailed explanations about the study and its procedures. Ethical considerations were upheld, and answer sheets and responses were provided to both the students and dentists.
The questionnaire consisted of questions related to the diagnosis, treatment, and causes of mandibular fractures, with each question having a correct answer. The frequency distribution of the answers to each question determined the level of knowledge among the dentists. In terms of the management of mandibular fractures, six questions were asked, with three correct answers indicating low knowledge, four to five correct answers denoting average knowledge, and six correct answers indicating good knowledge. Nine questions were posed regarding the care of mandibular fractures, with three correct answers reflecting low knowledge, four to seven correct answers representing average knowledge, and eight or nine correct answers signifying good knowledge.
The collected data were analyzed using SPSS software (version 26). The data were initially checked for quality. Descriptive statistics like frequencies, means, medians, standard deviations, and interquartile ranges were calculated to summarize the data. The study also estimated average scores and frequencies of knowledge, practice, and attitude. It should be noted that the Kolmogorov-Smirnov test was used to assess normality. Frequency, percentage, mean, and standard deviation were used to describe the data through tables and statistical charts. Independent t-test and Chi-square test were employed to determine relationships and analyze the data. In all analyses, a P-value of less than 0.05 was considered statistically significant.

Results
This study examined 200 individuals from the community of general dentists and final-year students of dentistry in an easy and accessible way. Specifically, the study examined 94 general dentists and 106 final-year students from Zahedan Faculty of Dentistry who met the entry criteria.
The mean age of the students was 24.4±6.2 years, while the mean age of the dentists was 36.6±8.4 years. In terms of gender distribution, male students made up 46.2% of the participants, while female students comprised 53.8%. Among general dentists, 43.6% were male, and 66.4% were female. The average working experience in general dentists was 9.4±3.1 years.
The study found that the most common cause of mandibular fracture was motor vehicle accidents (69.5%), followed by fights (7%), sports injuries (10%), falls (9%), and iatrogenicity following surgery (4.5%) (Figure 1). Clinical examination (9%), panoramic radiography (71.5%), CBCT (9%), and MRI (10.5%) were mentioned as the most reliable diagnostic tools and methods for mandibular fracture.
Regarding the primary treatment for patients with mandibular fractures, antibiotics (5.5%), painkillers (4%), fixation (73.5%), and surgery (17%) were mentioned as the primary treatment options. None of the participants mentioned the option of non-intervention (Figure 2).
The Chi-square test results showed that the distribution of answers to the question about the causes of mandibular fracture, diagnostic method for mandibular fracture, and initial treatment for patients with mandibular fracture was not significantly different between students and general dentists. Additionally, this test showed that the frequency distribution of answers did not differ significantly according to gender or work experience.

Figure 1: Frequency distribution of responses of general dentists and senior dental students to the most common causes of mandibular fractures


Figure 2: Freqeuency distribution of respones of general dentists and senior dental students to the primary treatment of mandibular fractures

In terms of knowledge regarding mandibular fracture management, 29.5% of participants had low levels of knowledge, while 36.5% had high levels of knowledge (Table 1). Regarding knowledge of mandibular fracture care, 21% had low levels of knowledge, while 41.5% had high levels of knowledge (Table 2).
The Chi-square test results also showed a significant difference in the level of knowledge regarding both mandibular fracture management and care between students and general dentists (P<0.05), with general dentists having a higher level of awareness.

Table 1: Frequency Distribution of Knowledge among Final Year Students of Zahedan Dental School and General Dentists Regarding the Management of Mandibular Fractures by Gender, Job Position, and Work Experience