Management of Fractures Through the Angle of the Mandible

What Is the Relationship Between Maxillofacial Injury Location and Associated Injuries?

BACKGROUND

Patients sustaining maxillofacial fractures are at risk for associated injuries (AIs) to other body regions. The incidence of AIs is reported to be from 20 to 35%. AIs may be life-threatening and play a key role in considering first-line management at the emergency department, as well as planning the definitive treatment of maxillofacial fractures.

PURPOSE

The study aimed to determine the frequency and risk factors for AIs in patients with maxillofacial fractures.

STUDY DESIGN, SETTING, SAMPLE

The investigators designed and implemented a retrospective cohort study of patients with facial fractures treated at Central Hospital (Lahti, Finland) from January 1, 2009 through December 31, 2019. All adult patients with verified maxillofacial fractures were included. Patients under 18 years of age were excluded from the study.

PREDICTOR VARIABLE

The predictor variable was the location of the maxillofacial fractures grouped into three categories: mandible alone, midface alone, and both midface and mandible.

MAIN OUTCOME VARIABLE(S)

The primary outcome variable was associated body region injuries coded as present or absent. The secondary outcome variable was the location of the AI categorized as skull, neck, thorax, pelvis, or extremity injuries.

COVARIATES

Other study variables included demographic data (age, sex, alcohol use), Glasgow Coma Scale, and etiology (fall, traffic- and bicycle accident, assault, pedestrian hit by motor vehicle, work-related, or sports/free-time injuries).

ANALYSES

Continuous variables were analyzed for normal distribution using the Shapiro-Wilks test and compared with categorical variables using the Mann-Whitney test. The univariate analyses of categorical variables were analyzed by the χ2 test (P ≤ .05 was considered statistically significant).

RESULTS

During the study period, 443 adult (≥18) patients had maxillofacial fractures. AIs were present in 88 subjects (20%). The mean age was 47.6 years (range 18-91); 52 years with AIs (range 19-91), and 47 years (range 18-92) without AIs (P = .03). Subjects with midface and mandible + midface fractures had greater risk to AIs compared to mandibular fractures (relative risk 2.0, P = .002, relative risk 2.8, P = .009).

CONCLUSION AND RELEVANCE

Every fifth maxillofacial trauma patient had an associated injury. Trauma patients should be evaluated in institutions with trauma protocols and imaging modalities before determining and executing the treatment plan for maxillofacial fractures.

Mandibular angle fractures: a demographic review, with particular reference to post-operative complications

BACKGROUND

Mandibular angle fractures (MAF) have a recognized complexity of treatment and an increased risk of incurring complications.

METHODS

This retrospective study included 45 consecutive patients who were diagnosed with an isolated MAF and no other facial fractures. The average age was 27.3 (SD = 7.7).

RESULTS

A comparatively low rate of complications (11.1%) and a low rate of reoperation (1.8%) are reported, along with a significant role of smoking in complications (p = 0.022). A non-significant association was noted between complications, male gender and assault as an aetiological factor.

CONCLUSIONS

Review of the data from this study confirms that complication rates for patients attending the National Maxillofacial Unit are similar to or better than that of international studies. An overview of the aetiology of fracture complications is included.

Biomechanical analysis of a novel screw system with a variable locking angle in mandible angle fractures

Locking plates nowadays represent an important treatment in bone trauma and bone healing due to its strong biomechanical properties. The purpose of this study was to both computationally and experimentally validate a novel screw locking system by comparing it to another locking system from state-of-the-art and to apply it in an environment of a fractured mandible. FEA was used to test both systems prior to experimental tests. The systems were locked in the plate holes at 0°, 10°, 15°, and 20°. Cyclic bending tests and push-out tests were performed in order to determine the stiffness and push-out forces of both locking systems. Finally, newly designed locking system was implemented in mandibular angle fracture. Control locking system was biomechanically superior in push-out test, but with no greater significance. In contrast, the new locking system showed greater stiffness by 17.3% at the deflection angle of 20° in cyclic tests, with lower values for other deflection angles. Similar values were displayed in fractured mandible angle environment. Greater stiffness of the new locking system in cyclic loading tests, together with polyaxiallity of the new locking screw, could lead to easier application and improved biomechanical stability of the mandible angle fractures.

New design titanium miniplate versus conventional miniplate in treatment of mandibular angle fractures: A comparative study

Introduction

Mandibular angle fracture (MAF) is the second most common site of all fractures of the mandible with the highest complication rate. Management of MAF has evolved in the past four decades. The purpose of the prospective study was to compare the efficacy of new design titanium miniplate (NDM) with conventional titanium miniplate (CTM) in the treatment of MAF.

Objectives

Mouth opening, occlusion, bite force measurement, and radiographs compared preoperatively and first week, first month and third month postoperatively.

Materials and Method

Fourteen patients diagnosed with MAF were randomly divided into two groups: Group A (seven patients) was treated with NDM and Group B (seven patients) with CTM. Patients were assessed preoperatively and postoperatively at an interval of one week, one month and three months.

Results

Repeated measures ANOVA and Post hoc Tukey test showed a significant increase in bite force and mouth opening for both groups in first and third postoperative months. Unpaired t-test showed slightly better mouth opening in Group B and slightly higher bite force in Group A.

Discussion

Both miniplates fulfilled all the study objectives and equally satisfactory healing was seen at the end of third month. NDM offers better stability, rigidity, and anatomic reduction of the fracture with a drawback of difficulty in adaptation and increased operative timing compared to CTM. Hence, we would like to conclude that both miniplates are equally efficient in the treatment of non-comminuted angle fractures with the NDM having upper hand in stability.

Should Degree of Third Molar Eruption Influence Operative Management of Mandibular Angle Fractures? A Systematic Review

Study Design

Systematic review.

Objective

There is a growing trend toward evidence-based management of third molars in the fracture line of mandibular angle fractures (MAFs). This study aimed to differentiate MAF fixation complications by degree of third molar eruption and by extraction strategy in patients undergoing Champy fixation.

Methods

PubMed, EMBASE, OVID, SCOPUS, the Cochrane Library, and clinicaltrials.gov were queried through May 2020 for English-language publications for MAFs with third molar involvement for this systematic review. Bias was assessed using author-defined criteria. Relative risk (RR) of post-operative complications associated with extracted unerupted and retained partially erupted third molars (Group I) was calculated against controls of retained unerupted and extracted partially erupted third molars (Group II).

Results

Ten studies reported complications by eruption or extraction; however, only one study stratified complications by both eruption and extraction to meet inclusion criteria. The risk of bias was medium as only cases meeting defined follow-up were included. 73 cases (N) were included: 34 qualified for Group I and 39 for Group II. Quantitative synthesis of individual case data demonstrated significantly higher complication rate in Group I compared to Group II (23.5% vs 5.1%) (RR 4.6, 95% CI 1.04-20.1). No significant differences were observed between groups for infectious complications, mechanical complications, nonunion, or dehiscence. Reoperation was required significantly more often for Group I (P = .043).

Conclusions

For MAFs involving the third molar, concomitant extraction of unerupted as well as retention of partially erupted third molars increases risk of complications with Champy fixation technique. For these patients, alternative strategies for fixation should be considered.

Mandibular Angle Fractures

Angle fractures are the most common among the mandibular fractures. History and physical examination are crucial in guiding time course and specifics of management. Computed tomography (CT) has become the gold standard for diagnosis of mandible fractures, offering advantages for both surgical planning and assessing dental involvement. Currently the use of a single monocortical plate with the Champy technique for osteosynthesis is used preferentially for noncomminuted fractures of the mandibular angle. Other load-sharing options for plating include strut plates, malleable plates, and geometric or 3D plates. Load-bearing options remain viable for comminuted fractures or other complex circumstances.

Impacted lower third molar relationship with mandibular angle fracture complications

INTRODUCTION

Mandibular angle fractures are very common and are associated with the highest risk of complications. The aim of this study is to evaluate the correlation between impacted lower third molar and mandibular angle fracture complications.

MATERIAL AND METHODS

All patients presenting with a mandibular angle fracture and at least 2 months follow up were retrospectively included. The following complications were recorded: post-traumatic malocclusion, mouth opening limitation, inferior alveolar nerve hypoesthesia, infection, delayed union, hardware loosening. The patients were divided in two groups: impacted lower third molar or erupted/absent lower third molar.

RESULTS

A total of 68 patients were included, lower third molar was impacted in 36 cases and erupted/absent in 32 cases. 40 complications were recorded in 27 patients at 2 months. No statistically significant difference could be found about malocclusion, mouth opening limitation and inferior alveolar nerve hypoesthesia. A lower rate of persistent inferior alveolar nerve hypoesthesia (p = 0.0557) in patients with impacted lower third molar (19.4%) was observed compared to patients without impacted lower third molar (40.6%). There was no occurrence of delayed union and hardware loosening in impacted lower third molar group, whereas 5 delayed unions and 4 hardware loosening were recorded in erupted/absent lower third molar group. Finally, the rate of patients with at least one of the 6 complications is significantly higher in the erupted/absent lower third molar group (17/32, 53.1%) than in the impacted lower third molar group (10/36, 27.8%), p = 0.033.

DISCUSSION

The risk of overall complication is decreased when lower third molar is impacted in mandibular angle fracture. This supports the idea of a role of the impacted lower third molar in fracture reduction and stability.

Photoelastic analysis of conventional and locking system for treatment of mandibular angle fractures with a single plate

Background

This photoelastic analysis evaluated stress distribution in different osteosynthesis systems, conventional and locking, used for treatment of mandibular angle fractures with a single plate.

Material and Methods

Angle fractures were simulated in mandibles made of photoelastic resin. Following Champy’s method, plate osteosynthesis was performed. The samples were divided into five groups: Group 1, non-fractured mandible; Group 2, two screws were installed in each segment using a conventional system; Group 3, two screws were installed in each segment using a locking system; Group 4, three screws were installed in the proximal segment and four screws in the distal segment using a conventional plate; Group 5, three screws were installed in the proximal segment and four screws in the distal segment using a locking plate. In an universal testing machine coupled to a polariscope, a load was applied to the first molar 10 times. The 50 images were randomly numbered and analyzed qualitatively and quantitatively by two raters.

Results

The locking system promoted better stress distribution along the osteosynthesis. The locking system reduced stress magnitude in the distal segment, with a significant between-group difference (P≤ 0.001).

Conclusions

The locking plate/screw system can distribute stress more evenly throughout the osteosynthesis, especially when long seven-hole plates are used.

Key words:Internal fracture fixation, osteosynthesis, mandibular fracture, bone plates.

Stability of bioabsorbable fixation systems according to different locations of mandibular fracture: A three-dimensional analysis

This study aimed to elucidate whether the stability of an unsintered hydroxyapatite particles/poly-_l-lactide (uHA/PLLA) system is comparable with that of titanium, according to different load-bearing areas of the mandible. The study included patients who underwent open reduction and internal fixation of the mandibular body, angle, or subcondylar fracture. The stability of uHA/PLLA systems was compared between the immediate and 6-month postoperative time points using three-dimensional cone-beam CT image analysis. The positional changes of each landmark were measured in three-dimensional (3D) coordinate systems using simulation software. Among 36 patients, there were more displacements of the landmarks between the immediate and 6-month postoperative time points after subcondylar fracture reduction than after body or angle fracture reductions. Strong upward displacements of the landmarks after subcondylar fracture reduction were found in the lateral pole [mean (SD) = 1.75 (3.16), p-value = 0.003] and medial pole [mean (SD) = 1.64 (2.50), p-value = 0.024], but not in the center. Subgroup analyses revealed similar unstable results in males on the condylar landmarks after subcondylar fracture reduction. There were tendencies for lateral displacement of the coronoid process in the body fracture group [mean (SD) = 0.8 (0.83)] and angle fracture group [mean (SD) = 0.75 (0.58)] postoperatively (p-value = 0.01). This study concluded that bioresorbable osteosynthesis can be recommended for body or angle fractures, while the indication for subcondylar fractures is less clear.

Transbuccal Approach in Management of Mandible Angle Fracture

With expanding dimensions and an eminent member of trauma team many Ear Nose Throat specialists are exposed to Oro-maxillofacial trauma. Mandibular angle is a difficult region to operate owing to its unique anatomy. Anglefractures form around 30-40% of the mandibular fracture. Open reduction and internal plating is the management of choice in most angle fractures and various approaches have been described in literature. We conducted a study of trans-buccal approach for management of mandibular angle fractures. It was a non-randomised observational study. 57 patients of mandible angle fractures were included in the study. The ORIF was done in these pts under general anaesthesia after careful surgical planning using trans-buccal approach. This approach included an intraoral exposure with stab incision for the trans-buccal passage of drill and screw diver. Out of 57 cases in our study 33 were males and 24 were females. 23/57 patients were in age group 25-35 years whereas 19/57 patients were in age group 15-25 years All 57 patients had good fracture healing. Occlusion dysfunction was seen in only 1 case. Infection was seen 3 cases while intraoral exposure of plates occurred in 2 cases. Average mouth opening was 43.3 mm at 6 weeks with progressive improvement on follow up. Extraoral scar healed well with very good cosmesis in all cases. We strongly suggest the use of transbuccal approach for ORIF in mandibular angle fractures owing to the ease of procedure, comfort of surgeon and less complication rate.

Rehabilitation strategies in maxillofacial trauma: systematic review and meta-analysis

PURPOSE

This study aims to investigate rehabilitation strategies to reduce trismus, pain, and edema in patients with maxillofacial trauma.

METHODS

An electronic search in main databases was performed, including studies published until November 2017. Clinical trials aiming to investigate therapeutic techniques to improve mandibular range of motion and to reduce pain and edema compared to other treatments were included.

RESULTS

Nine studies were included in the review with different therapy modalities: photobiomodulation, kinesiologic tape, hilotherapy, jaw exercises, and TENS. Only five studies had available data to be included in a meta-analysis. There were no differences between any of the proposed strategies and its controls to prevent trismus. Individuals treated with hilotherapy presented less pain compared to controls. Kinesiologic tape or hilotherapy reduced edema when compared to controls daily until postoperative day 3.

CONCLUSIONS

There is diversity among the proposed rehabilitation techniques, and types of fractures and there are few numbers of included participants in each study. The results obtained in this review do not promote evidence to guide the use of non-drug rehabilitation techniques in patients with maxillofacial trauma after surgical intervention.

Atypical Mandibular Angle Fracture

The mandibular fracture takes the second position among facial bones fractures, with significant increase of cases in the last years. The aim of this paper is to report a clinical case of a patient with facial trauma due to an automotive accident, resulting in an atypical fracture in a unilateral mandibular angle. In the image examinations an atypical favorable fracture in the right mandibular angle region involving the apex of the erupted 48 tooth was found. The fracture line started in the posterior region of mandibular ramus, below mandibular condyle, and spread out until inferior border of the mandible in premolar region. Despite the atypical design of the mandibular angle fracture described in this paper, the treatment showed satisfactory results, without any aesthetic or functional changes for the patient.

Postoperative CT of the Mandible Following Trauma: Review of Normal Appearances and Common Complications

RATIONALE AND OBJECTIVES

Surgeons aim to restore occlusion and jaw function to baseline status for patients with mandibular fractures using either closed treatment or reduction and fixation.

MATERIALS AND METHODS

Occlusion is defined as the relationship between the maxillary and mandibular teeth as they approach each other.

RESULTS

Radiologists should be familiar with the goals of repair to help identify which treatment is adequate as well as to diagnose potential complications. Some of the more common complications encountered are infection, nonunion or malunion, and malocclusion.

CONCLUSION

We provide a comprehensive review of both the desired and untoward CT findings after surgical repair of traumatic mandibular injuries.

The effect of the mandibular plane angle on fracture line stability: An ex vivo experimental study

BACKGROUND/AIMS

Mandibular angle fractures fixated with plate osteosynthesis techniques have to withstand the effects of muscle attachments. Individual variations in the craniofacial morphology may alter the biomechanical resistance of the bone-plate construct. The aim of the present study was to determine the influence of variations in the mandibular plane angle (MPa) on the biomechanical stability of sheep mandibular angle fractures (MAFs).

MATERIALS AND METHODS

Sixty sheep hemi-mandibles were used. The mandibles were positioned on a test jig that simulated low (15°, group L), normal (25°, group N), and high (35°, group H) MPa. Unfavorable MAFs were created with thin diamond cutting disks. One four-hole, 9.0-mm-spacing, standard titanium miniplate of 2.0 mm thickness and 5.0-mm-long screws were inserted at the superior border of the alveolar bone in monoplanar orientation. Specimens were then subjected to vertical loads between 10 N and 150 N in a universal testing machine. The displacement values at each 10 N force increment and the load magnitude at which 3.0 mm displacement limit was reached were recorded.

RESULTS

Starting from 40 N, the displacement values at each 10 N increment in the H group were significantly higher than those of the L and N groups until 150 N (P < 0.05). The force magnitude required to reach 3.0 mm of displacement in the H group was significantly lower than that for the L and N groups (P < 0.05 for each).

CONCLUSIONS

The one-miniplate monoplanar fixation technique used in sheep MAF with high MPa is more likely to offer lower biomechanical resistance to the vertical forces applied over the molar region than do the normal and low MPa.

A comparison of panoramic radiography and cone beam computed tomography in the detection of osteosynthesis complications in sheep mandibular angle fractures

OBJECTIVE

The aim of this study was to compare the diagnostic efficacy of panoramic radiography (PANO) and cone beam computed tomography (CBCT) in detecting simulated complications of plate osteosynthesis applied to mandibular angle fractures (MAFs).

STUDY DESIGN

Unfavorable MAFs were created in 100 fresh sheep hemimandibles. Fractures were fixed with 4-hole titanium miniplates and screws. Bone necrosis around the screws, penetration of the screw into the inferior alveolar canal, screw loosening, and plate breakage were simulated. The diagnostic efficacy of the imaging techniques was compared by using intra- and interobserver agreement scores and area under the receiver operating characteristic curve (AUC) values. Examination time (ET), confidence scores (CS), and planar preference (PP) in CBCT evaluation were assessed.

RESULTS

Intra- and interobserver agreement scores varied between 0.61 and 0.91. AUCs for screw penetration into the inferior alveolar canal and screw loosening were significantly higher in CBCT than in PANO (P < .05). CBCT presented significantly higher ET and CS values compared with PANO (P < .05). PP showed significant differences among types of complications (P < .05).

CONCLUSIONS

PANO provided acceptable outcomes in the detection of bone necrosis and broken plates around the screw, but CBCT was more likely to enable detection of all simulated types of complications with higher confidence.

Postoperative Complications Associated With Different Fixation Methods of Isolated Mandibular Angle Fractures

The objective of this study was to review the medical records of patients with a history of mandibular angle fracture who were attended at the Service of Oral and Maxillofacial Surgery and Traumatology of FOAr/UNESP in the last 5 years. The data collected were subjected to chi-squared test (significance level of 5%). The authors reviewed 19 medical records. The main cause was physical aggression (58.00%), but with no statistical difference in relation to the other etiologies (P > 0.05). Regarding the type of fixation, one 2.0-mm system plate associated with one 2.4-mm system plate and the fixation using only two 2.0-mm system plates were used in 7 patients each. The fixation method with a monocortical plate at the upper border was used in 5 patients. However, there was no statistically significant difference in the frequency of complications among the 3 fixation methods used (P > 0.05). In 52.64% of the patients, the third molar was removed intraoperatively. Despite this, there was no statistically significant difference in the frequency of complications when the third molar was in the fracture line or when it was removed postoperatively (P > 0.05). The complications observed were dehiscence associated with pain (44.44%), trismus (22.22%), infection (22.22%), and presence of bone spicules (11.11%). However, no statistical differences were observed between the frequency of different types of complications (P = 0.779). In the sample studied, there were no differences in the frequency of complications among the fixation methods applied.

Mandible Fractures

Mandible fractures account for a significant portion of maxillofacial injuries and the evaluation, diagnosis, and management of these fractures remain challenging despite improved imaging technology and fixation techniques. Understanding appropriate surgical management can prevent complications such as malocclusion, pain, and revision procedures. Depending on the type and location of the fractures, various open and closed surgical reduction techniques can be utilized. In this article, the authors review the diagnostic evaluation, treatment options, and common complications of mandible fractures. Special considerations are described for pediatric and atrophic mandibles.

Osteosynthesis using cannulated headless Herbert screws in mandibular angle fracture treatment: A new approach?

INTRODUCTION

Fractures of the mandibular angle are a common type of facial skull fracture. Although operative treatment includes a wide range of fixation techniques, a definite gold standard method has yet to be established. Headless, cannulated Herbert screws, often used in many forms of minimally invasive trauma surgery, provide functional and stable fracture fixation.

MATERIALS AND METHODS

In a prospective, double-randomised, controlled, parallel-group - designed, in vitro trial, the biomechanical behaviour of the Herbert bone screw system was compared to that of a conventional locking plate system in 40 mandibular angle fractures of human mandible cadaver phantoms.

RESULTS

The mean stress values were 250 (±68.0) N in the plate subgroup and 200 (±61.0) N in the screw subgroup. The respective mean strain values were 7.90 (±2.7) mm and 6.90 (±2.2) mm, and the respective mean stiffness were values 1.10 (±0.61) N/m and 0.78 (±0.40) N/m. The differences in the results obtained using the two treatments were not significant (p = 0.55).

CONCLUSIONS

The biomechanical behaviour of the two fixation systems within the tested loads did not significantly differ with respect to postoperative parameters clinically relevant in osteosynthesis. Both systems met the mandibular angle assessment criterion, which is considered to be sufficient for clinical use. The results indicate the potential clinical utility of these two systems, and recommend further testing.

Comparison of Management of Mandibular Angle Fractures by Three Approaches

BACKGROUND AND OBJECTIVES

Various methods have been reported in the literature for treating mandibular angle fractures comparing extra oral, intra oral and transbuccal approaches for achieving the goals of restoration of anatomic form, maintenance of segment position and bony union.

MATERIALS AND METHODS

This study was conducted to assess the simple and effective surgical approach in treating mandibular angle fractures and the outcome by means of three approaches i.e. intra oral, transbuccal and extra oral approaches.

RESULTS/CONCLUSION

A total of 45 patients with mandibular angle fracture were divided into three groups. Group I-intra oral approach-15 patients, Group II-transbuccal with intraoral approach-15 patients, Group III-extra oral approach-15 patients. The results of our study found intraoral approach to be much better because it is simple, precise, duration is short, and post operative complications are less with minimal morbidity and pain.

Clinical outcomes of three different types of hardware for the treatment of mandibular angle fractures: a comparative retrospective study

A retrospective study was conducted to compare the clinical outcomes of three different types of hardware that are used in mandibular angle fracture fixation. Thirty patients were selected from the hospital database. The patients were categorized into the following groups: group A, in which a single 2.0-mm locking miniplate was used; group B, in which a single rigid 2.3-mm plate was used; and group C, in which a single lag screw was inserted. All patients were followed for 6 months. With regard to intraoperative variables, significant differences were found among the groups in the duration of surgery and cost. Group C had the shortest surgical time, followed by group A and then group B. Two patients, one in group A and one in group B, suffered an occlusal discrepancy after surgery. Of the group A patients, two exhibited wound dehiscence and one had an infection. One patient in group B had an exposed plate. Sensory nerve involvement was noted in three group C patients and one group B patient. The lag screw was associated with the fewest complications and exhibited all of the advantages of plating systems in the treatment of angle fracture. The lag screw involved the least hardware and a short operating time, however the differences were not significant.

The Comprehensive AOCMF Classification System: Mandible Fractures- Level 2 Tutorial

This tutorial outlines the details of the AOCMF image-based classification system for fractures of the mandible at the precision level 2 allowing description of their topographical distribution. A short introduction about the anatomy is made. Mandibular fractures are classified by the anatomic regions involved. For this purpose, the mandible is delineated into an array of nine regions identified by letters: the symphysis/parasymphysis region anteriorly, two body regions on each lateral side, combined angle and ascending ramus regions, and finally the condylar and coronoid processes. A precise definition of the demarcation lines between these regions is given for the unambiguous allocation of fractures. Four transition zones allow an accurate topographic assignment if fractures end up in or run across the borders of anatomic regions. These zones are defined between angle/ramus and body, and between body and symphysis/parasymphysis. A fracture is classified as "confined" as long as it is located within a region, in contrast to a fracture being "nonconfined" when it extents to an adjoining region. Illustrations and case examples of mandible fractures are presented to become familiar with the classification procedure in daily routine.

Common dental and orofacial trauma: evaluation and management

This article reviews common dental and orofacial traumatic injuries, and provides a broad overview and general principles of the diagnosis and management of common dental and orofacial injuries. Such knowledge will aid the physician in recognition and assessment of injury, proper treatment, and appropriate referral to the specialist. Although many of these injuries warrant appropriate consultation, a sound understanding of assessment and treatment protocol is important.

Does the Relationship between Retained Mandibular Third Molar and Mandibular Angle Fracture Exist? An Assessment of Three Possible Causes

The objective of this study is to discuss problems associated with dental retention through three clinical cases of mandible fractures related to the presence of retained lower third molars, emphasizing the possibility of mandible fractures resulting from this or from the extraction procedure. The three evaluated patients had a fracture in the mandible angle. The third molars were present in all the cases, as was the relationship of the fracture with the teeth. After evaluating the three cases and reviewing literature, it is believed that the presence of the retained lower third molars and the surgical procedures for their extraction increase the risk of mandible angle fractures.

A Prospective Study of Strut versus Miniplate for Fractures of Mandibular Angle

This prospective randomized clinical trial compared the treatment outcomes of strut plate and Champy miniplate in fixation of mandibular angle fractures. Patients with mandibular angle fracture were consented and enrolled into this study. Exclusion criteria include patients with severely comminuted fractures. The patients were randomly assigned to receive the strut plate or Champy miniplate for angle fracture fixation. Patient demographics, fracture characteristics, operative and postoperative outcomes were collected prospectively. Statistical analysis was performed to evaluate the significance of the outcome. A total of 18 patients were included in this study and randomly assigned to receive either the strut plate or Champy miniplate. Out of which five patients were excluded postoperatively due to complex fracture resulting in postoperative maxillomandibular fixation. The final enrollment was 13 patients, N = 6 (strut) and N = 7 (Champy). There was no statistically significant difference in the pretreatment variables. Nine of these patients had other associated facial fractures, including parasymphyseal and subcondylar fractures. Most of the (11) patients had sufficient follow-up after surgery. Both groups exhibited successful clinical unions of the mandibular angle fractures. The complications associated with the mandibular angle were 20% in the strut plate group and 16.7% in the Champy group. One patient in the strut plate group had a parasymphyseal infection, requiring hardware removal. The strut plate demonstrated comparable surgical outcome as the Champy miniplate. It is a safe and effective alternative for management of mandibular angle fracture.

The 7-hole angle plate for mandibular angle fractures

PURPOSE

To evaluate the 7-hole angle plate for open reduction, internal fixation of mandibular angle fractures when the Champy technique is inadequate and more rigid or semirigid fixation is beneficial and to provide rational indications for the choice of the 7-hole angle plate.

PATIENTS AND METHODS

Retrospective evaluation of 10 patients selected at Parkland Memorial Hospital over a 2-year period when the 7-hole angle plate stabilized their angle fracture. Patients were evaluated for postoperative complications including pain, malocclusion, and infection.

RESULTS

All 10 patients had sufficient follow-up for inclusion in this retrospective study. Correct placement of the 7-hole angle plate, easily accomplished with adequate assistance, produced no reportable postoperative complications.

CONCLUSION

The 7-hole angle plate is a good first option when more rigid or semirigid fixation is required, and the best fallback when the Champy technique is ineffective.

[Maxillary and mandibular fractures. Treatment concepts in maxillofacial surgery]

Maxillary and mandibular fractures are a relatively frequent occurrence due to the exposed location of the jaws and are caused mainly by acts of violence, traffic and recreational accidents. Mandibular fractures can be treated conservatively with dental splints and intermaxillary fixation. Since Michelet, miniplate osteosynthesis via intraoral access has become the method of choice. Champy showed that the monocortical fixation of miniplates at the level of the linea obliqua results in stable osteosynthesis, despite postoperative micro-movements in the fracture gap, and postulated the principle of dynamic compression. Dislocated fractures of the mandibular collum are treated with stable osteosynthesis via an intra- or extraoral approach, while fractures of the mandibular joint are usually treated conservatively and early functional rehabilitation is favored. For mandibular fractures, the principle of load-bearing and load-sharing should be considered, i.e. in the case of sufficient bone and uncomplicated fractures, the bone can bear most of the force, such that miniplates are sufficient (load-sharing). If bones are weakened by atrophy or in the case of infected, comminuted or defect fractures osteosynthesis plates must bear the load alone (load-bearing).

A new biomechanical model for evaluation of fixation systems of maxillofacial fractures

The aim of this study was to develop a new type of biomechanical model for biomechanical researches of maxillofacial fractures and then evaluate it. Twenty synthetic polyurethane maxillary and mandibular models were used to simulate the mandible and maxilla. Springs were used to represent the forces of masseter, medial pterygoid, temporalis, and lateral pterygoid muscles acting on the models. Four masticatory conditions, namely clenching in the intercuspal position (ICP), incisal clenching (INC), left unilateral molar clenching (L-MOL, contralateral side of fracture) and right unilateral molar clenching (R-MOL, fracture side) were simulated. The strain on a miniplates placed across a simulated fracture was measured using strain gauges attached to the plate surface. During INC and L-MOL, the strain on the miniplates confirmed the findings of Champy. The upper miniplate was subjected to tension force and the lower miniplate to compression. When the bite point moved to the fracture, the tension-compression zone reversed, with the upper miniplate relatively compressed and the lower miniplate tension. During ICP, the tension-compression zone changed again, with both miniplates tension. In conclusion, we have successfully developed a model which is much closer to physiological conditions than models used previously. It is reliable and useful for biomechanical tests of mandibular fractures. Models including soft tissue need developing to further understand fracture healing biomechanics.

Equivalence randomized controlled trial of bioresorbable versus titanium miniplates in treatment of mandibular fracture: a pilot study

PURPOSE

The present study was undertaken to test bioresorbable fixation versus titanium for equivalence in terms of clinical union and complications using the American Association of Oral and Maxillofacial Surgeons parameters of care. The study design was a randomized, controlled, equivalence trial.

MATERIALS AND METHODS

A total of 40 patients were enrolled and allocated to the titanium group and bioresorbable group using a computerized randomization table. All were plated using standard plating principles. In the bioresorbable group, 2 weeks of maxillomandibular fixation was also used. Evaluation of the study endpoint was done at 8 weeks postoperatively. For statistical analysis, the upper limit of the 95% confidence interval was calculated for failure to achieve the primary outcome variable and compared with the maximal clinically acceptable difference between the standard and test modalities in the failure to achieve clinical union (delta). Delta was predetermined as 2%. The other complications were tested for significance using Fisher's exact test.

RESULTS

Of the 40 patients, 21 were in the titanium group and 19 were in the bioresorbable group, with 20 men and 1 woman in the titanium group and 18 men and 1 woman in the bioresorbable group. The mean age was 28.7 years in the titanium group and 26.6 years in the bioresorbable group. In the titanium group, the complications noted were nonunion in 0%, malocclusion in 7.7%, continued postoperative swelling in 0%, chronic pain in 2%, infection in 5.2%, an inability to chew hard food after 8 weeks in 7.7%, the need for alternative treatment in 0%, and the need for reoperation in 31%. In the bioresorbable group, the complications were nonunion in 4.17%, malocclusion in 11.1%, swelling in 8.3%, chronic pain in 37.5%, infection in 0%, an inability to chew hard food in 11.1%, the need for alternative treatment in 11.1%, and need for reoperation for plate removal in 0%.

CONCLUSIONS

The small sample size did not allow any meaningful conclusion to be drawn from the present study in terms of the primary question of achieving union. Both groups matched in outcomes when evaluated only on a clinical basis. The avoidance of repeat surgery for plate removal is a definite advantage of using resorbable plates. However, the results are inconclusive in favor of any particular plating system.