Dental Trauma in Association with Maxillofacial Fractures: an Epidemiological Study

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Dental Traumatology 2015; doi: 10.1111/edt.12176 Dental trauma in association with maxillofacial fractures: an epidemiological study

Muhammad Ruslin1,2, Jan Wolff2, Abstract – Aim: The aim of this study was to retrospectively investigate Paolo Boffano2, Henk S. Brand2,3, the incidence and associated factors of dental trauma in patients with max- Tymour Forouzanfar2 illofacial fractures at the VU Medical Center in Amsterdam. Material and 1Department of Oral and Maxillofacial Surgery methods: Data from 707 patients who were treated surgically for maxillofa- Faculty of Dentistry, University of Hasanuddin, cial fractures were evaluated. The data were collected retrospectively from Makassar, Indonesia; 2Department of Oral and patient files and other available databases. The data collected included date Maxillofacial Surgery/Oral Pathology, VU of fracture, age, gender, type of fracture, and injured teeth. Result: Of the University Medical Center/Academic Center for total 707 patients, 164 patients (23.2%) presented dental injuries associated 3 Dentistry Amsterdam (ACTA); Department of with facial fractures. Mandibular condylar fractures, mandibular parasym- Medical-Dental Interaction, Academic Center for physeal fractures, Le Fort fractures, and mandibular body fractures were Dentistry Amsterdam (ACTA), Amsterdam, The found to be significantly more associated with dental injury. Zygomatic Netherlands arch or zygomatic complex fractures were significantly less associated with dental injury. Women had a significant higher risk of facial fractures with dental injuries than men. The maxilla demonstrated the highest incidence Key words: Dental trauma; maxillofacial of injured teeth. The most affected teeth were the maxillary incisors fractures; epidemiology (33.1%), followed by mandible incisors (13.6%), mandible molars (12.8%), Correspondence to: Muhammad Ruslin and and maxillary premolars (12.6%). Conclusion: Our findings show a higher Tymour Forouzanfar, Department of Oral and risk of dental injury among patients with a mandibular condylar fracture Maxillofacial Surgery/Oral Pathology, VU and mandibular parasymphyseal fracture but a lower risk of dental injury University Medical Center, P.O. Box 7057, among patients with a zygomatic arch or zygomatic complex fracture. On 1007 MB Amsterdam, The Netherlands. De Boelelaan 1117 1081 HV Amsterdam. average, patients had more than three injured teeth, with most of the Tel.: +020 444 4444 injured teeth being in the upper jaw. The maxillary incisors, followed by Fax: 020 444 1024 the mandible incisors, were the most injured teeth. e-mails: [email protected]; [email protected] (M. Ruslin); [email protected] (T. Forouzanfar) Accepted 28 February, 2015

When a maxillofacial trauma occurs, the most common ing, seven articles have been published in several types of injuries are facial soft tissue injury and dental countries that describe the frequency and type of dental injury. The prevalence of dental injury is highly world- injury associated with maxillofacial fractures (2, 12– wide and mostly occurs in childhood and adolescence 17). These studies have shown that the prevalence of (1–6). Andreasen et al. (1, 7) found injuries to perma- dental injuries in patients with facial bone fractures nent anterior teeth in one in four adults and in one in ranges from 13% up to 23% (2, 12, 13, 16, 17). Excep- five children. The prevalence of dental injury varies tions to these findings are the research of Zhou et al. considerably between countries (2–6), and it is deter- (14) and da Silva et al. (15). These researchers found mined by many factors such as behavioral and cultural the prevalence of patients with dental injuries in combi- diversity, social and economic status, the age of the nation with facial fractures to be 41.8% and 2.1%, population that is investigated, and the lack of stan- respectively. Many of the patients studied were aged dardization in dental trauma research. between 20 and 30 years (14, 16). Depending on the severity of the accident, fractures Dental trauma may influence the treatment of facial to facial bones may also occur. Trauma resulting in fractures and usually requires postoperative dental only maxillofacial fractures has been frequently studied treatment, which in turn requires good communication (8–15). Findings show the age group most susceptible with the treating dentist. Furthermore, facial fractures to only facial fractures is 19–30 years (9, 10, 12, 14, can also have an influence on the treatment of dental 15), although some researchers have reported that the injuries. In some cases, dental treatment is not possi- 20–40 years age group is the most susceptible (11–13). ble after fracture reduction due to facial swelling and Dental injury that is associated with other maxillofa- can lead to subsequent premature tooth loss in some cial trauma is also commonly seen. At the time of writ- cases.

In the Netherlands, maxillofacial surgeons commonly perform first aid dental treatment. This makes it impor- Results tant to understand the prevalence of dental trauma in In total, 707 patients with facial fractures were relation to facial fractures. A previous study performed included in the study. Table 1 shows the descriptive in the Netherlands by van den Bergh et al. (9) investi- statistics. The study population comprised 525 males gated the incidence and etiology of maxillofacial trauma. and 182 females, giving a male-to-female ratio of 2.9:1. They found zygomatic and mandibular bone fractures to The mean age of the patients was 33.6 years, with a be the most common bone fracture in both men and range from 2 to 88 years. The majority of patients (233 women. Together, these fractures account for approxi- patients, 33.0%) with facial fractures were aged 20 to mately 80% of all facial fractures. A study that investi- 29 years. No significant difference between males and gates the relationship between dental injuries and facial females was found (chi-squared test). Of these patients, fractures in the Netherlands has yet to be performed. 164 patients (23.2%) presented dental injuries associ- The aim of this present study was therefore to retrospec- ated with facial fractures. Of these, 106 were male and tively investigate the incidence and associated factors of 58 female, giving a male-to-female ratio of 1.8:1. Their dental trauma in patients with maxillofacial fractures at mean age was 31.4 years, ranging from 5 to 69 years. the VU University Medical Center, Amsterdam, from Most of the patients (55 patients, 33.5%) with associ- January 2000 until March 2013. ated dental injury were aged 20–29 years (Table 1). Furthermore, results showed women had a significant higher risk of facial fractures with dental injuries than Materials and methods men (chi-squared, P = 0.001), and men had a signifi- This study is based on an analysis of a patient database cant higher risk of only facial fractures than women from the Department of Oral and Maxillofacial Surgery, (P = 0.001). Vrije Universiteit University Medical Center (VUmc), Among the total group, 1231 maxillofacial bone Amsterdam, the Netherlands. The patient database com- fractures were recorded, which accounts for a mean prised retrospectively collected data from January 1, of 1.74 fractures per patient. The mean for patients 2000, until January 1, 2010, and a systematic computer- with dental injury associated with fractures proved to assisted database that has continuously recorded be higher (mean 2.48; P < 0.05). Table 2 shows that patients with maxillofacial fractures between January 1, the zygomatic complex is the most fractured bone 2010, and March 1, 2013. The study was performed (25.35%), followed by the mandibular condyle according to the guidelines of the Medical Ethics Com- (22.7%). In contrast to this finding, the lower third mittee of the Free University of Amsterdam. of the face was more susceptible to fractures than the Only surgically treated patients were included in the upper two-thirds. Looking at the group with facial study. Totally edentulous patients, patients with a nose fractures and dental injuries, the mandibular condylus fracture or fractures in the dentoalveolar complex, and proved to be most fractured bone (38.7%), followed patients who received no surgical treatment were by fractures of the mandibular parasymphyseal region excluded from the study. The patient data included (22.4%). No dental injury was found with the zygo- date of fracture, age, gender, type of fracture, and site matic arch fractures. In this group, the lower third of of injured teeth. In the study, patients were divided the face was also more susceptible to fractures than into three groups based on their age at the time of the upper two-thirds of the face. Statistical analysis trauma: children (0–12 years), teenagers (13–19 years), showed that dental injury occurred significantly more and adults (20 years and older). Adult patients were frequently in association with mandibular condylar further categorized into the age groups: 20-29, 30-39, fracture (P < 0.001), mandibular parasymphyseal frac- 40-49, 50-59, 60-69, 70-79, and 80 years and older. ture (P < 0.001), Le Fort fracture (P < 0.001), and The facial fractures were subdivided into fractures of mandibular body fracture (P = 0.049) (Table 2). the frontal sinus, orbital fractures, fractures of the There is a significantly lower risk for dental injury in zygoma complex, zygomatic arch fractures, Le Fort I/ association with injury in the zygomatic region II/III fractures, mandibular coronoid fractures, condy- (P < 0.001). lar fractures, mandibular ramus fractures, mandibular A total of 508 injured teeth were observed (aver- angulus fractures, mandibular body fractures, and aged 3.55 teeth per patient). Table 3 shows the num- parasymphyseal fractures. All of these fractures were bers and distribution of the injured teeth. The maxilla registered on the left side, the right side, or on both had the most injured teeth (308 teeth). The teeth most sides. The site of the injured teeth was classified as affected were the maxillary incisors with 168 teeth maxillary or mandibular and then further subdivided in (33.1%), followed by 69 mandible incisors (13.6%), 65 incisors, canines, premolars, and molars. The type of mandible molars (12.8%), and 64 maxillary premolars dental injury was not further specified. (12.6%). Statistical analysis was performed using SPSS (version As seen in Table 4, the major cause of facial frac- 18.0) to assess the relationship between dental injury tures accompanied by dental injury was traffic acci- and other relevant variables. The data were analyzed dents followed by falls and violence. Furthermore, in using the chi-squared test, the independent-sample t- the dental injury group, it was observed that the inci- test, and the one-sample t-test, and P-values of 0.005 dence of sport as a cause of injury was significantly or less were considered to be statistically significant. lower when compared with the total population.

Table 1. Descriptive statistic Total patient group Patients with only dental injuries Gender Gender Age (years) Male (%) Female (%)Total (%) Male (%) Female (%) Total (%) 0–9 3 (0.6) 3 (1.6) 6 (0.8) 0 1 (1.7) 1 (0.6) 10–19 73 (13.9) 22 (12.1) 95 (13.4) 22 (20.8) 10 (17.2) 32 (19.5) 20–29 182 (34.7) 51 (28.0) 233 (33.0) 37 (35.0) 18 (31.0) 55 (33.5) 30–39 118 (22.5) 37 (20.3) 155 (21.9) 24 (22.6) 14 (24.1) 38 (23.2) 40–49 88 (16.8) 33 (18.1) 121 (17.1) 11 (10.4) 9 (15.5) 20 (12.2) 50–59 38 (7.2) 17 (9.3) 55 (7.8) 8 (7.5) 3 (5.2) 11 (6.7) 60–69 17 (3.2) 12 (6.6) 29 (4.1) 4 (3.8) 3 (5.2) 7 (4.3) 70–79 4 (0.8) 6 (3.3) 10 (1.4) 0 0 0 80–89 2 (0.4) 1 (0.5) 3 (0.4) 0 0 0 Total 525 (100) 182 (100) 707 (100) 106 (100) 58 (100) 164 (100)

Table 2. Facial fractures and presence of dental injury Dental injuries Site No (%) Yes (%) Total (%) Upper 2/3 Frontal sinus 34 (4.1) 13 (3.2) 47 (3.8) Orbital 30 (3.6) 12 (3.0) 42 (3.4) Le Fort 56 (6.8) 51** (12.6) 107 (8.7) Zygomatic complex 287** (34.8) 24 (5.9) 311 (25.3) Zygomatic arch 39** (4.7) 0 (0.0) 39 (3.2) Total upper 2/3 446 (54.1) 100 (24.6) 546 (44.4) Lower 1/3 Mandibular condylar 122 (14.8) 157** (3.2) 279 (22.7) Coronoid process 8 (1.0) 5 (3.0) 13 (1.1) Mandibular ramus 4 (0.5) 1 (12.6) 5 (0.4) Mandibular angle 76 (9.2) 20 (5.9) 96 (7.8) Mandibular body 80 (9.7) 32** (0.0) 112 (9.1) Mandibular parasymphysis 89 (10.8) 91** (24.6) 180 (14.6) Total lower 1/3 379 (45.9) 306 (24.6) 685 (55.6) Total 825 (100.0) 406 (100.0) 1231 (100.0)

*Chi-squared test, P < 0.05; **Chi-squared test, P < 0.001.

Amsterdam area. Patients who did not receive surgical Table 3. Dental injuries treatment were excluded from the study. In this study, Total we found a prevalence of dental injury in association with facial fractures of 23.2%. Iso-Kungas et al. (17) Maxilla found a similar prevalence of 22.5%, although their Incisor 168 population comprised only pediatric patients. Our Canine 21 prevalence of dental injury in association with facial Premolar 64 Molar 55 fractures was higher than the prevalence found by Lie- Total maxilla 308 ger et al. (13) with 19.5%, Thoren et al. (12) with Mandible 16%, Gassner et al. (18) with 18.9%, Roccia et al. (16) Incisor 69 with 13.1%, but lower than the prevalence found by Canine 20 Zhou et al. (14) (41.8%). The relatively high prevalence Premolar 46 of dental injury in our study can partly be explained by Molar 65 our inclusion criteria. We were mainly interested in Total mandible 200 patients who had received surgical treatment for their Total 508 maxillofacial injury. Therefore, patients treated non- surgically had probably suffered less severe trauma without any associated dental injury. Discussion In our total study population, most of the patients Our study evaluated all patients presenting with facial were aged between 20 and 29 years. This is in agree- trauma accompanied with dental injury at the VU Uni- ment with the majority of the recent studies that have versity Medical Center (VUmc) in Amsterdam, the investigated facial fractures (8–12, 14, 15). Lieger et al. Netherlands, over a period of 13 years. VU University (13) found that most patients were between 31 and Medical Center is a University Hospital and one of the 40 years old. However, their study group also con- main hospitals that treats facial injuries in the greater tained totally edentulous patients. Of the 164 patients

Table 4. Etiology of maxillofacial fractures Patients with maxillofacial fractures (%) Patients with maxillofacial fractures and dental injuries (%) Fall 128 (18.1) 43* (26.2) Traffic accident pedestrian 16 (2.3) 2 (1.2) Traffic accident bicycle 159 (22.5) 64* (39.0) Traffic accident TWMV 90 (12.7) 20 (12.2) Traffic accident CAR 34 (4.8) 7 (4.3) Sport 83 (11.7) 5* (3.0) Violence 173 (24.5) 20* (12.2) Work 7 (1.0) 1 (0.6) Other 17 (2.4) 2 (1.2) Total 707 (100) 164 (100)

*Significance, P < 0.001. with facial fractures and dental injury, most were ted for bicycle accidents and not for interpersonal vio- between 20 and 29 years old. This finding is in line lence. As a result, those patients treated for bicycle with other recent studies on maxillofacial fractures (14, accidents at the VUmc have a higher susceptibility to 16, 18). The prevalence of isolated dental injury varies fractures in the lower third of the face. considerably (1), but tends to occur most frequently in Our results showed that the mandibular condylar children and adolescents (1, 2, 4, 5, 18). Iso-Kungas fracture, mandibular parasymphyseal fracture, Le Fort et al. (17) investigated a group of pediatric patients fracture, and mandibular body fracture were signifi- and found higher figures than were found in other cantly more associated with dental injury. Lieger et al. studies that focused on adults. They concluded that found that patients with dental injury had a higher risk dental injury together with facial fractures was gener- of symphysis fractures, followed by condylar fractures. ally more complicated in children than in adults (17). Zhou et al. (14) also found significantly more dental As in other studies, we found a male predominance injury with only symphysis fractures. Other authors in both the total group and the group with dental reported that dental injury was significantly more asso- injury with facial fractures (8, 12–18). This is a similar ciated with mandibular fractures (12, 16, 17). However, finding to studies that investigated dental injury only. da Silva et al. (15) observed more maxillary fractures Many of these studies found a male-to-female ratio of than mandibular fractures with dental injury, although 2:1 (4, 9, 21). However, in our study we found that this conclusion was based on only seven patients with women had a statistically higher association for dental facial fractures combined with dental injury. injuries with facial fractures compared with their male The results of the present study show a mean of 3.55 counterparts. Roccia et al. (16) found the same associa- injured teeth per patient. This is higher than the find- tion. However, Thoren et al. (12) worked in the same ings of Thoren et al. (12) who found a mean of 2.5 field and found no significant association between gen- injured teeth, Iso-Kungas et al. (17) who found a mean der and incidence of dental injury. of 3.2 injured teeth, and Roccia et al. (16) who found a In this present study, the bone most susceptible to mean of 2.8 injured teeth per patient. Zhou et al. (14) fracture was the zygomatic complex, followed by the found a higher mean number of injured teeth per mandibular condylar. Thoren et al. (12) reported patient (4.68 teeth), but they also reported a higher slightly different results, with mandibular fractures number of patients with dental injuries than in our being the most prevalent, followed by zygomatico-orbi- study. The maxilla contained the most injured teeth in tal fractures. In the group with facial fractures and our patient group. Other studies have reported similar dental injury, the mandibular condyle was the most results (12–14, 16); one study found a similar number fractured bone, followed by the mandibular parasym- of injured teeth in the upper and lower jaw (17). Simi- physeal region. This corresponds to the findings of lar to other studies (12–14, 16, 17), our study found Roccia et al. (16) who reported the same results. Fur- maxillary incisors to be the teeth most effected, fol- thermore, we found that the lower third of the face lowed by the mandibular incisors. This corresponds was more susceptible to fractures than the upper two- with the findings of studies that investigated isolated thirds of the face in both the group with dental injury dental injuries, where most of the injured teeth were in and the group without dental injury. This contrasts the anterior segment (4, 7, 19–22). with the findings of other researchers who found that Several studies (22–26) have reported a temporal most fractures occurred in the upper two-thirds of the shift in the importance of different causes of facial face in the group without dental injury (12, 15, 16). bone fractures. In particular, the role of traffic acci- However, in accordance with the findings of our sur- dents as a cause of facial bone fracture has decreased, vey, most studies have reported the lower third of the whereas the number of facial bone fractures caused by face to be more susceptible to fractures in the group violence and sport injuries has increased. However, in with facial fractures and dental injury (12, 15–17). One our study, we found injuries caused by two-wheeled explanation for the higher incidence of facial fractures motor vehicle (TWMV) accidents have increased signif- in the lower third of the face found in our study could icantly and sport-related accidents have significantly be that most patients in the Amsterdam area are trea- decreased. Although we did not find a significant

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