Management of the fractured edentulous atrophic mandible

Evidence-Based Medicine for Mandible Fracture Repair: Current Controversies and Future Opportunities

Mandibular fractures are among the most common facial fractures resulting from trauma. The nature of the injury, involved facial structures, presence of associated injuries, the dental status of the patient, comorbid conditions, and psychosocial context all must be considered by the surgeon when planning the optimal treatment for these patients. While consensus exists for many aspects of the management of mandibular trauma, some elements remain controversial. Three such topics-antibiotic therapy, treatment of subcondylar fractures, and management of the third molar-remain particularly controversial, with significant heterogeneity in practice patterns and without widely accepted evidence-based guidelines to standardize care. The goals of this work are to (1) review the historical perspective underlying these controversies, (2) summarize recent evidence shaping the current debate, and (3) highlight opportunities for continued efforts to identify best practices.

The Causes and Prevalence of Maxillofacial Fractures in Iran: A Systematic Review

Background

Maxillofacial fractures are a common type of injury that can result in significant morbidity and mortality. We aimed to systematically review the literature on the prevalence and causes of maxillofacial fractures in Iran to estimate the overall prevalence of maxillofacial fractures and the most common causes.

Methods

A systematic search of PubMed, Cochrane Library, Web of Science (WS) and Google Scholar (GS) electronic databases was conducted to identify relevant articles published up to January 2023. Studies reporting the prevalence and causes of maxillofacial fractures in Iran were included in the analysis. MOOSE guidelines were adopted for the current systematic review. No data or language restriction were applied. Risk of bias across the articles was assessed.

Results

A total of 32 studies comprising 35,720 patients were included in the analysis. The most common cause of maxillofacial fractures was road traffic accidents (RTAs), accounting for 68.97% of all cases, followed by falls (12.62%) and interpersonal violence (9.03%). The prevalence of maxillofacial fractures was higher in males (81.04%) and in the age group of 21-30 years (43.23%). Risk of bias across studies was considered low.

Conclusion

Maxillofacial fractures are a significant public health problem in Iran, with a high prevalence and RTAs being the leading cause. These results highlight the need for increased efforts to prevent maxillofacial fractures in Iran, especially through measures to reduce the incidence of RTAs.

Augmentation of the Atrophic Mandible with a Block Corticomedullary Graft

The gradual loss of the dental alveolus leads to bone resorption, which may cause atrophy of the maxilla and mandible. One of the most complex procedures in reconstructive surgery is the rehabilitation of patients with atrophic mandibles. Herein, we present a clinical case study of atrophic mandible augmentation with grafts obtained from the iliac crest. The use of reconstruction plates may represent a feasible mechanism for treatment as well as fracture prevention. Mandible augmentation performed by grafting the donor site of the iliac crest showed satisfactory results and resolution of the aesthetic and functional impairments.

Achievements of the Cochrane Iran Associate Centre: Lessons Learned

Healthcare decision-making is a process that mainly depends on evidence and involves increasing numbers of stakeholders, including the consumers. Cochrane evidence responds to this challenge by identifying, appraising, integrating and synthesizing high-quality evidence. Recently, a collaborative effort has been initiated in Iran with Cochrane to establish a representative local entity. A variety of multifaceted interventions were conducted according to Cochrane’s strategy to 2020, such as producing evidence, making Cochrane evidence accessible, advocating for evidence and building an effective and sustainable organization. In this report, the authors present the two and half year performance and achievements of Cochrane Iran based on a comprehensive and systematic approach. This case might be an example of health diplomacy, which is initiated by a successful international collaboration and proceed with recognizing the importance of adherence to the strategic action plans and goals.

Surgical management of unilateral body fractures of the edentulous atrophic mandible

INTRODUCTION

Management of body fractures in patients with edentulous atrophic mandibles represents a challenging task due to patient's age, medical comorbidities, poor bone quality, and vascularity, as well as reduced contact area between the fracture ends. The aim of the study was to assess the demographic and clinical variables, the surgical technique, and outcomes of unilateral body fractures of the edentulous atrophic mandible managed at several European departments of oral and maxillofacial surgery.

METHODS

This study is based on a systematic computer-assisted database that allowed the recording of data of all patients with fractures of the atrophic edentulous mandible from the involved maxillofacial surgical units across Europe between 2008 and 2017. The following data were recorded for each patient: gender, age, comorbidities, etiology, synchronous body injuries, degree of atrophy of the mandible according to Luhr classification, type of surgical approach and fixation, length of hospitalization, and presence and type of complications.

RESULTS

A total of 43 patients were included in the study: 17 patients' mandibles were classified as class I according to Luhr, 15 as class II, and 11 as class III. All patients underwent open reduction and internal fixation by extraoral approach in 25 patients, intraoral in 15 patients, and mixed in 3 patients. A single 2.0 miniplate was used in 16 patients, followed by a single 2.4 reconstruction plate in 13 patients, by two 2.0 miniplates, and three 2.0 miniplates. Outcome was considered to be satisfying in 30 patients, with no complications. Complications were observed in 13 cases.

CONCLUSIONS

Treatment of unilateral body fractures of the edentulous mandible must still be based on the type of fracture, degree of atrophy, experience of the surgeon, and patients' preference. An adequate stability can be obtained by different plating techniques that have to be appropriately tailored to every single specific patient.

A historical perspective with current opinion on the management of atrophic mandibular fractures

The management of atrophic mandibular fractures has been a challenge for maxillofacial surgeons for decades. During the past 70 years, various techniques for treating edentulous mandibular fractures have been advocated. These techniques have been praised, criticized, abandoned, improved, and used in combination with other methods. Although some of the principles of management outlined before the end of World War II are still valid in today's technological era, other concepts did not survive the test of time. The aim of this paper is to examine the evolution of treatment modalities for the management of atrophic mandibular fractures that have been employed over the years. Debates and discussions generated by this topic are included. Current techniques and treatment philosophies with thoughts for future therapies are provided.

Virtual Surgical Planning for the Management of Severe Atrophic Mandible Fractures

Severely atrophic mandible fractures are frequently a challenge to treat. Virtual surgical planning (VSP) uses three-dimensional computed tomographic (CT) scans that can be translated into stereolithographic models to fabricate surgical templates, facilitating intraoperative procedures. The purpose of this article is to describe the reconstruction of two cases of severe atrophic mandible fracture using VSP. Two elderly edentulous/partially dentate patients who presented with fractures of their mandibles and who underwent reconstruction using VSP were included. Both had Class III atrophy at the region of the fracture. While both fractures were complex, the mechanism of injury differed with one being a tractor accident and the other being a pathologic fracture. Both patients presented with critical medical conditions. CT scans were obtained on both. The displaced segments were aligned virtually using mirror images and the midline of the maxilla. Three-dimensional models were fabricated to allow preoperative contouring of 2.5-mm reconstruction plates. Patients were operated under general anesthesia and fractures reduced and stabilized with 2.5-mm reconstruction plates placed at the lateral border of the mandible. Average treatment time for both patients was a little over 2 hours. There was good reduction with both. VSP is a valuable tool to assess and reduce complex fractures with less surgical time and predictable results.

Analysis of the blood supply to the post-fracture edentulous mandible: study by colour Doppler sonography

PURPOSE

This study assessed the arterial blood supply to the mandible of edentulous patients treated for mandibular fractures using colour Doppler ultrasound.

METHODS

The blood supply of edentulous patients surgically treated for mandibular fractures (group A) and edentulous fracture-free individuals (group B) was assessed. Only the fractured sides were evaluated in the first group (N = 17), whereas each side was evaluated in the second group (N = 20). The arterial flow of six sites was assessed. The systolic-peak maximum velocity (SPV), final diastolic velocity (FDV), resistive index (RI), pulsatility index (PI), acceleration and flow direction of each artery were obtained. Additionally, the presence of local vascular obstructive factors was evaluated. The differences between groups were analysed using the Kruskal-Wallis test, which was complemented by the Mann-Whitney test, for correlations between the degree of alveolar atrophy and the study factors (p < 0.050).

RESULTS

There was a significant decrease in the flow of certain arteries, especially the submental (SPV, p = 0.007, PI, p = 0.022, and acceleration, p = 0.015), in the fracture group. The facial artery in both groups showed lower values related to local obstructive factors (SPV, p = 0.001, FDV, p = 0.040, and PI, p = 0.030). The submental artery flow was higher (SPV, p = 0.006, and FDV, p = 0.009) in non-atrophic individuals.

CONCLUSIONS

There was a decreased flow mainly in the submental artery, but there were no cases of major vascular injury in edentulous patients treated for mandibular fractures.

An unusual case of atrophic mandible fracture in a patient with osteogenesis imperfecta and on oral bisphosphonate therapy: Case report

Fractures of severely atrophic (height < 10 mm) edentulous mandibles are infrequent and challenging to manage. Factors such as sclerotic bone and decreased vascularity combined with systemic diseases complicate the management of such fractures. Osteogenesis imperfecta (OI) is a heterogeneous group of inherited disorders of type I collagen metabolism. Patients with OI characteristically present with histories of long bone fractures, deformities, blue sclerae, and opalescent dentin. However, fractures of the facial skeleton are rare. Bisphosphonate therapy has been proven to effectively reduce the fracture risk in patients with OI. The purpose of this clinical report is to present an unusual case of spontaneous fracture of the atrophic mandible in a patient with OI. Despite open reduction and internal fixation (ORIF) with miniplate osteosynthesis, the patient developed a second fracture at a screw placement site distal to the first fracture. The patient was successfully treated with ORIF using locking reconstruction plates fixed in the symphyseal and angle regions. Bone healing following ORIF was normal, and no clinical sign of osteonecrosis as a result of bisphosphonate therapy was observed. Patients with OI can present with spontaneous fractures of already weakened mandibles. Although such fractures can be managed with care using established protocols, further research is required to examine the effects of concomitant medication, such as bisphosphonates.

Treatment of edentulous mandibular fractures with rigid internal fixation: case series and literature review

The aim of the study is to analyze the effectiveness of rigid internal fixation (RIF) for treating edentulous mandibular fractures. Because of the low incidence of fractures in edentulous mandible, there is no consensus of the optimal treatment for it. This study included all edentulous patients with mandibular fracture diagnosis, who were treated with internal fixation at the Hospital Italiano de Buenos Aires from November 1991 to July 2011. Data such as age, gender, etiology and location of fracture, surgical approach, type of osteosynthesis used, and postoperative complications were analyzed. A total of 18 patients, 76.2 years mean age, 12 females (66.6%), presented a total of 35 mandibular fractures. The mandibular body was the most common localization of the fractures. Twenty-five fractures received surgical treatment with RIF, mainly approached extraorally. Reconstruction plates were the most common type of fixation used. Fracture reduction was considered satisfactory in 96.5%, with 22.2% of complications and 11.1% of reoperations needed. Open reduction and RIF demonstrated to be a reliable method for treating edentulous mandibular fractures. Nevertheless, there is lack of high-level recommendation publication to support this.

Interventions for the management of mandibular fractures

BACKGROUND

Fractures of the mandible (lower jaw) are a common occurrence and usually related to interpersonal violence or road traffic accidents. Mandibular fractures may be treated using open (surgical) and closed (non-surgical) techniques. Fracture sites are immobilized with intermaxillary fixation (IMF) or other external or internal devices (i.e. plates and screws) to allow bone healing. Various techniques have been used, however uncertainty exists with respect to the specific indications for each approach.

OBJECTIVES

The objective of this review is to provide reliable evidence of the effects of any interventions either open (surgical) or closed (non-surgical) that can be used in the management of mandibular fractures, excluding the condyles, in adult patients.

SEARCH METHODS

We searched the following electronic databases: the Cochrane Oral Health Group's Trials Register (to 28 February 2013), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2013, Issue 1), MEDLINE via OVID (1950 to 28 February 2013), EMBASE via OVID (1980 to 28 February 2013), metaRegister of Controlled Trials (to 7 April 2013), ClinicalTrials.gov (to 7 April 2013) and the WHO International Clinical Trials Registry Platform (to 7 April 2013). The reference lists of all trials identified were checked for further studies. There were no restrictions regarding language or date of publication.

SELECTION CRITERIA

Randomised controlled trials evaluating the management of mandibular fractures without condylar involvement. Any studies that compared different treatment approaches were included.

DATA COLLECTION AND ANALYSIS

At least two review authors independently assessed trial quality and extracted data. Results were to be expressed as random-effects models using mean differences for continuous outcomes and risk ratios for dichotomous outcomes with 95% confidence intervals. Heterogeneity was to be investigated to include both clinical and methodological factors.

MAIN RESULTS

Twelve studies, assessed as high (six) and unclear (six) risk of bias, comprising 689 participants (830 fractures), were included. Interventions examined different plate materials and morphology; use of one or two lag screws; microplate versus miniplate; early and delayed mobilization; eyelet wires versus Rapid IMF™ and the management of angle fractures with intraoral access alone or combined with a transbuccal approach. Patient-oriented outcomes were largely ignored and post-operative pain scores were inadequately reported. Unfortunately, only one or two trials with small sample sizes were conducted for each comparison and outcome. Our results and conclusions should therefore be interpreted with caution. We were able to pool the results for two comparisons assessing one outcome. Pooled data from two studies comparing two miniplates versus one miniplate revealed no significant difference in the risk of post-operative infection of surgical site (risk ratio (RR) 1.32, 95% CI 0.41 to 4.22, P = 0.64, I(2) = 0%). Similarly, no difference in post-operative infection between the use of two 3-dimensional (3D) and standard (2D) miniplates was determined (RR 1.26, 95% CI 0.19 to 8.13, P = 0.81, I(2) = 27%). The included studies involved a small number of participants with a low number of events.

AUTHORS' CONCLUSIONS

This review illustrates that there is currently inadequate evidence to support the effectiveness of a single approach in the management of mandibular fractures without condylar involvement. The lack of high quality evidence may be explained by clinical diversity, variability in assessment tools used and difficulty in grading outcomes with existing measurement tools. Until high level evidence is available, treatment decisions should continue to be based on the clinician's prior experience and the individual circumstances.

Use of gunning splint for the treatment of edentulous mandibular fracture: a case report

Treating edentulous mandibular fracture is difficult in elderly patients due to compromised medical condition of the patient and various contraindications for the surgical approach. The complication rate of infection or malunion is higher compared to fractures in younger, dentulous patients. For such conditions, 'Gunning splint' is a better option as it provides close reduction and stabilization of mandibular fracture, thus improving the prognosis.

Surgical treatment of the atrophic mandibular fractures by locked plates systems: our experience and a literature review

The management of atrophic mandibular fractures in edentulous patients represents an insidious issue for the maxillofacial surgeon due to the biological and biomechanical conditions that are unfavorable for fracture fixation and bone healing. The purpose of this study was to evaluate the results of the treatment of atrophic mandibular fractures and to compare the outcomes of different plating systems used for stabilization. We selected a study group of 16 patients with fractures of completely edentulous atrophic mandibles who were treated in our department between 2004 and 2010. All patients were surgically treated by open reduction and internal rigid fixation using 2.0-mm large-profile locking and 2.4-mm locking bone plates. All patients achieved a complete fracture healing and fast functional recovery of mandibular movements without intraoperative or postoperative surgical complications. The results of our study demonstrated the efficacy of this type of treatment in association with a low postoperative complication rate, a reduction in the recovery time, and the possibility to have an immediately functional rehabilitation. There were very similar results using each of the two bone plating methods considered: no case had hardware failure or nonunion of the fracture. The 2.0-mm large locking plate is thinner, exposes through the soft tissues less frequently, and is much easier to shape and adapt to the mandibular anatomy. However, the 2.4-mm locking plate system still represents the reference hardware in the condition of severe bone atrophy.

Comparative finite element analysis of the biomechanical stability of 2.0 fixation plates in atrophic mandibular fractures

PURPOSE

The objective of the present study was to conduct a computational, laboratory-based comparison of the biomechanical stability of 2.0 fixation locking plates with different profiles in Class III atrophic mandibular fractures using 3-dimensional finite element analysis.

MATERIALS AND METHODS

Three-dimensional finite element models simulating Class III atrophic mandibular fractures were constructed. The models were divided into 4 groups according to plate thickness (1.0, 1.5, 2.0, and 2.5 mm). Fractures were simulated in left mandibular bodies, and 3 locking screws were used on each side of each fracture for fixation. Bite forces of approximately 63 N were simulated in the incisor and molar regions of the mandibles in finite element models.

RESULTS

The level of compressive strain on the bone around the screw was within the physiological limit. No significant difference was observed in the displacement of bone segments in the fracture region. Von Mises stress was higher during simulated bites in the molar region for plates with thicknesses of 1.0 mm. Plate tension values were below the level required for permanent deformation or fracture in all models. The 2.5-mm-thick plate presented better biomechanical performance than all other plates. The 2.0-mm-thick plate also showed satisfactory results and adequate safety limits.

CONCLUSION

Large-profile (2.0-mm-thick) locking plates showed better biomechanical performance than did 1.0- and 1.5-mm-thick plates and can be considered an alternative reconstruction plate for the treatment of Class III atrophic mandibular fractures.

A novel technique for attaining maxillomandibular fixation in the edentulous mandible fracture

Edentulous mandible fractures present a unique and challenging surgical problem, particularly because of lack of occlusive dental surfaces to capitalize upon maxillomandibular fixation (MMF). We present a novel technique to achieve MMF using rigid plates spanning the oral cavity to fixate the maxilla to the mandible. The process is rapid and allows stability using the established principles of rigidity, external fixation, and osteosynthesis. This technique allows for a faster MMF than with a Gunning splint and allows for easier oral hygiene. An illustrative case and pre- and postoperative imaging are provided.

Fixation of atrophic edentulous mandible fractures by bone plating at the inferior border

PURPOSE

No consensus has been reached regarding the best treatment for repair of fractures of the severely atrophic mandible (<10 mm vertical height). The most complete Cochrane review of the published data could not substantiate a single best practice recommendation for treating these fractures. The present study reports the results of such treatment by placing miniplates at the inferior border of the mandible of 23 fractures of the mandibular body in 16 patients.

MATERIALS AND METHODS

This was a consecutive case series during a 30-year period performed by a single surgeon at several practice locations using the technique of extraoral plating at the inferior border. All patients were prospectively monitored clinically and radiographically for achievement of bony union and for complications of sensory disturbances of the lower lip, delayed healing, and hardware removal. The mean observation time was 23.1 months (range 1 to 60), with only 2 cases observed for less than 6 months.

RESULTS

All the patients achieved clinical union of their fractures. Two cases of fibrous union did not reach ossification until 5 months after surgery. The hardware removal rate was 13.6%, and the infection/prolonged inflammation rate was 13.6%. There was 1 case of malunion. Those patients who had dentures were able to return to denture wearing postoperatively.

CONCLUSIONS

Miniplate fixation of fractures of the severely atrophic mandible at the inferior border is safe and effective.

A genetic association study of single nucleotide polymorphisms in FGFR1OP2/wit3.0 and long-term atrophy of edentulous mandible

BACKGROUND

After dental extraction, the external surface of alveolar bone undergoes resorption at various rates, and a group of patients develop excessive jawbone atrophy. Oral mucosa overlying the atrophied jawbone is unusually thin; therefore, we have hypothesized that excessive jawbone atrophy may be associated with abnormal oral mucosa contraction. FGFR1OP2/wit3.0, a cytoskeleton molecule initially identified in oral wound fibroblasts, has been shown to induce oral mucosa contraction after dental extraction. This study examined the genetic association between single nucleotide polymorphisms (SNPs) of FGFR1OP2/wit3.0 and excessive atrophy of edentulous mandible.

METHODS AND FINDINGS

First, the expression of FGFR1OP2/wit3.0 was determined in gingival tissues of 8 subjects before and after dental extraction. In situ hybridization revealed that all subject increased FGFR1OP2/wit3.0 expression in the post-operative oral mucosa tissues; however, significantly high levels of FGFR1OP2/wit3.0 were observed in 3 out of 8 subjects. In a separate study, 20 long-term edentulous subjects (66.4 ± 9.4 years) were recruited. Tag-SNPs in the FGFR1OP2/wit3.0 allele were determined by Taqman-based polymerase chain reaction. The mandibular bone height was determined following the American College of Prosthodontists (ACP) protocol. Subjects with minor allele of rs840869 or rs859024 were found in the highly atrophied group by the ACP classification (Chi square test, p = 0.0384 and p = 0.0565, respectively; Fisher's Exact, p= 0.0515 and p = 0.2604, respectively). The linear regression analysis indicated a suggestive association between rs859024 and the decreased bone heights (Mann-Whitney, p = 0.06). The average bone height of the subjects with rs840869 or rs859024 minor alleles (10.6 ± 3.2 mm and 9.6 ± 3.2 mm, respectively) was significantly smaller than that of those subjects with the major alleles (14.2 ± 4.5 mm, p<0.05).

CONCLUSIONS

The patients with the minor allele of rs840869 or rs859024 were associated with excessive atrophy of edentulous mandible. This study may provide the basis for a genetic marker identifying susceptible individuals to develop jawbone atrophy after dental extraction.

Fractures of the mandibular condyle: evidence base and current concepts of management

Management of mandibular condylar fractures remains a source of ongoing controversy. While some condylar fractures can be managed non-surgically, recognition of fracture patterns that require surgical intervention and selection of an appropriate operative procedure are paramount to success in treating these injuries.The objective of this review is to appraise the current evidence regarding the effectiveness of interventions that are used in the management of fractures of the mandibular condyle.