Key points in surgical management of mandibular condylar fractures

Mandibular condylar fractures are among the most common facial fractures and some of the most difficult to manage.Opinions about the management of mandibular condylar fractures differ among surgeons.With the implementation of new technology,an increased understanding of fracture man-agement,and better functional and morphological outcomes reported in the literature,open reduction and internal fixation is becoming many surgeons preferred choice for the treatment of condylar fractures.Because surgical treatment of such fractures is complex,certain factors must be considered to achieve satisfactory outcomes.In this article,we summarise six key points in the management of mandibular condylar fractures:virtual evaluation of condylar fracture,a suitable surgical approach,good reduction,stable internal fixation,repair of the articular disc,and restoration of the mandibular arch width.We believe that these points will help to improve the prognosis of mandibular condyle fractures.

Virtual surgical planning is a useful tool in the surgical management of mandibular condylar fractures

Purpose:The aim of this study is to evaluate the application value of virtual surgical planning in the management of mandibular condylar fractures and to provide a reliable reference.Methods:This was a prospective randomized controlled study and recruited 50 patients requiring surgical treatment for their mandibular condylar fractures.The inclusion criteria were patients(1)diagnosed with a condylar fracture by two clinically experienced doctors and required surgical treatment;(2)have given consent for the surgical treatment;and(3)had no contraindications to the surgery.Patients were excluded from this study if:(1)they were diagnosed with a non-dislocated or only slightly dislocated condylar fracture;(2)the comminuted condylar fracture was too severe to be treated with internal reduction and fixation;or(3)patients could not complete follow-up for 3 months.There were 33 male and 17 female patients with 33 unilateral condylar fractures and 17 bilateral condylar fractures included.The 50 patients were randomly(random number)divided into control group(25 patients with 35 sides of condylar fractures)and experimental group(25 patients with 32 sides of condylar fractures).Virtual surgical planning was used in the experimental group,but only clinical experience was used in the control group.The patients were followed up for 1,3,6 and 12 months after operation.Variables including the rate of perfect reduction by radiological analysis,the average distance of deviation between preoperative and postoperative CT measurements using Geomagic software and postoperative clinical examinations(e.g.,mouth opening,occlusion)were investigated for outcome measurement.SPSS 19 was adopted for data analysis.Results:The average operation time was 180.60 min in the experimental group and 223.2 min in the control group.One week postoperatively,CT images showed that the anatomic reduction rate was 90.63%(29/32)in the experimental group and 68.57%(24/35)in the control group,revealing significant difference(X^(2)=4.919,p=0.027).Geomagic comparative analysis revealed that the average distance of deviation was also much smaller in the experimental group than that in the control group(0.639 mm vs.0.995 mm;t=3.824,p<0.001).Conclusion:These findings suggest that virtual surgical planning can assist surgeons in surgical procedures,reduce operative time,and improve the anatomic reduction rate&accuracy,and thus of value in the diagnosis and treatment of condylar fractures.

Experimental Study on Anatomic Reduction of Lateral Pterygoid Muscle(Simulated Manipulation Fracture Reduction)and Condylar Free Reduction for Condylar Fracture

[Objectives]To compare the fracture healing of keeping lateral pterygoid muscle anatomic reduction(simulated manipulation fracture reduction)with condylar free reduction in the treatment of condylar fractures.[Methods]Twenty-four New Zealand rabbits were randomly divided into two groups to mandibular condylar neck fracture model was established.one team keep the lateral pterygoid muscle,the other excise it.Cervical vascular perfusion was done with ink before animals executed after operation 2,4,6 and 8 weeks.Bilateral anteroposterior and mediolateral condylar diameters measured.Changes of operation side condylar proliferating layer,microvessel number and bone parameters were observed and analyzed after slices and HE staining.[Results]The mediolateral condylar diameters of operation side were significantly smaller than health side in condylar free reduction group at the 4,6,8 weeks(P<0.05),but there was no statistical difference in the anteroposterior condylar diameters at each time point(P>0.05).There were no significant differences in the anteroposterior and mediolateral condylar diameters of the anatomic reduction lateral pterygoid muscle group compared between the operation side and health side(P>0.05).The number of microvessel in condylar free reduction group were smaller than those in anatomic reduction lateral pterygoid muscle group(P<0.05).There were significant differences in BV/TV,Tb.Th,Tb.Sp between the condylar free reduction group and the anatomic reduction lateral pterygoid muscle group(all P<0.05),and the Tb.N were significantly differences between two groups at the 4,6,8 weeks(P<0.05).[Conclusions]When the condyle is fractured it should keep lateral pterygoid muscle(manipulation fracture reduction)as possible,which is important in the fracture healing and functional recovering of mandibular.

Correlation between Condylar Fracture Pattern after Parasymphyseal Impact and Condyle Morphological Features： A Retrospective Analysis of 107 Chinese Patients

Background： The treatment of the condylar fractures is difficult. Factors that result in the fractures are complex. The objective of this morphometric study was to investigate the relationship between condylar fracture patterns and condylar morphological characteristics. Methods： We conducted a retrospective analysis of 107 patients admitted to the West China Hospital of Stomatology for bilateral condylar fractures caused by parasymphyseal impact. The patients were divided into five groups according to the type of condylar fracture. Ten parameters were evaluated on three-dimensional （3D） reconstruction mandible models through the Mimics 16.0 （Materialize Leuven, Belgium） anthropometry toolkit. Each parameter of the 3D models was analyzed using multivariate analysis. Multinomial logistic regression analyses were used to examine the relationships between the five groups. Results： The results showed that the differences of condylar head width （M 1 ）, condylar neck width （M3）, the ratio of condylar head width to condylar anteroposterior diameter （M1/M2）, the ratio of condylar head width to condylar neck width （M1/M3）, the ratio of condylar height to ramus height （M8/M7）, and mandibular angle （M10） were statistically significant （p 〈 0.05）. Type A condylar head fractures were positively associated with M1 （compared to Type B： OR ：1.627, 95% CI： 1.123, 2.359; compared to Type C： OR = 1.705, 95% CI： 1.170, 2.484） and M1/M2 （compared to Type B： OR = 1.034, 95% CI： 0.879, 2.484）. Type B condylar head fractures were negatively associated with M l 0 （compared to Type C： OR = 0.909, 95% CI： 0.821, 1.007）. Condylar neck fractures were negatively associated with M3 （compared to condylar head： OR = 0.382, CI： 0.203, 0.720 ; compared to condylar base： OR = 0.436, 95% CI： 0.218, 0.874）, and positively associated with M 1/M3 （compared to condylar head： OR = 1.229, 95% CI： 1.063, 1.420 compared to condylar base： OR = 1.223, 95% CI： 1.034, 1.447）. Condylar base fractures were positively associated with M10 （OR = 1.095, 95% CI： 1.008, 1.189） and negatively associated with M8/M7 （OR = 0.855, 95% CI： 0.763, 0.959） as compared with condylar head fractures. Conclusions： Condylar fracture pattern is associated with the anatomical features of the condyles when a fracture occurs from parasymphyseal impact.

Mini suture anchor: An effective device for reduction and fixation of displaced temporomandibular joint disc with intracapsular condylar fracture

Purpose::The main aim is to provide clinical reference for the application of mini suture anchor in the reduction and fixation of displaced temporomandibular joint(TMJ)disc with intracapsular condylar fracture.Methods::From October 2018 to October 2019,21 patients(31 sides)with intracapsular condylar fractures and articular disc displacement from West China Hospital of Stomatology,Sichuan University were included.The selection criteria were:(1)mandibular condylar fractures accompanied by displacement of the TMJ disc,confirmed by clinical examination,CT scan and other auxiliary examinations;(2)indication for surgical treatment;(3)no surgical contraindications;(4)no previous history of surgery in the operative area;(5)no facial nerve injury before the surgery;(6)informed consent to participate in the research program and(7)complete data.Patients without surgical treatment were excluded.The employed patients were followed up at 1,3,6 and 12 months after operation.Outcomes were assessed by success rate of operation,TMJ function and radiological examination results at 3 months after operation.Data were expressed as number and percent and analyzed using SPSS 19.0.Results::All the surgical procedures were completed successfully and all the articular discs were firmly attached to the condyles.The articular disc sufficiently covered the condylar head after the fixation.The fixation remained stable when the mandible was moved in each direction by the surgeons.No complications occurred.The functions of the TMJ were well-recovered postoperatively in most cases.CT scan revealed that the screws were completely embedded in the bone without loosening or displacement.Conclusion::Mini suture anchor can provide satisfactory stabilization for the reduced articular disc and also promote the recovery of TMJ functions.