A re-evaluation of the importance of disc position in temporomandibular disorders

A guide for temporomandibular joint surgery using a simple surgical classification - A narrative-style review

The aim of this narrative style review is to clarify the role of TMJ surgery in the management of specific TMJ disorders by introducing a simple and practical surgical classification. A decade ago, a new surgical classification was published which, like the Wilkes classification, included the five escalating degrees of joint pathology, but with more practical definitions and proposed surgical options for each of the disease categories. The classification begins with Category 1 - painful but otherwise structurally normal joints, which are largely managed nonsurgically. Categories 2 and 3 denote reducing and nonreducing disc displacement of the TMJ, respectively, with the former treated by TMJ arthrocentesis or level 1 arthroscopy and the latter best managed with disc repositioning or discopexy. Category 4 describes degenerative changes to the disc itself, where the disc cannot be salvaged and is thus removed with TMJ discectomy. Lastly, Category 5 refers to end-stage joint disease, where none of the joint components can be salvaged; both the disc and condylar head are sacrificed, and the TMJ is reconstructed with a prosthetic total joint replacement. In the decade since its publication, various studies have served to validate the usefulness of the TMJ surgical classification, and how it can be applied to better understand the role of TMJ surgery in everyday clinical practice.

Temporomandibular Disorders: Surgical Implications and Management

Temporomandibular disorders are a group of conditions that interfere with the daily lives of patients. Pain and limited function are primary concerns, and general dentists are usually the primary clinicians to be made aware of this issue. Evaluation and diagnosis is the key to determining a management plan. Minimally invasive surgical treatment includes arthrocentesis and arthroscopy, which can reduce inflammatory mediators, thereby reducing pain and increasing joint function. Open joint surgery for internal derangements focuses on instrumentation to remove and reshape the diseased condyle and disc as arthroplasty. Patients with severely limited function are candidates for total joint replacement.

Comparison of symptoms, signs, gender, and magnetic resonance images of temporomandibular joint disorder patients

OBJECTIVE

To compare patients' complaints, clinician's examination findings, and magnetic resonance imaging (MRI) findings by considering gender.

METHODS

Temporomandibular joint (TMJ) pain, difficulty in mouth opening, masseter tenderness, deviation, clicking sound, bruxism, restriction, normal occlusion and normal mouth opening symptoms, and findings of temporomandibular disorder (TMD) patients who came to the author's outpatient clinic were recorded. These recordings were compared with MRI.

RESULTS

In the study, symptoms, signs, and MRIs of 276 TMD patients were analyzed, including gender. No difference was observed in terms of symptoms, signs, or MRI results for either gender. MRI findings were correlated with restriction and normal mouth opening in both groups (p < 0.05). Normal MRI findings were observed in 52.5% of the MRI results.

CONCLUSION

Except for normal mouth opening and limitation, MRI findings did not provide a significant result. Therefore, careful detection of symptoms and signs rather than MRI helps in diagnosis.

Imaging temporomandibular disorders: Reliability of a novel MRI-based scoring system

The aim of this study was to assess the inter- and intrarater reliability of a recently proposed scoring system for temporomandibular disorders (TMD), based upon radiological findings from magnetic resonance imaging (MRI). Patients with clinically suspected uni- or bilateral TMD, and subsequently conducted MRI examination of both temporomandibular joints, were included in this study. MRI data were independently evaluated by two experienced radiologists according to the DLJ scoring system proposed by Wurm et al., which includes assessment of the following categories: articular disk (prefix 'D'), direction of disk luxation (prefix 'L'), and osseous joint alterations (prefix 'J'). 60 patients (49 female and 11 male) were eligible for analysis. No significant differences were found between both observers regarding 'D' and 'L' scores (p = 0.13 and p = 0.59, respectively). Significant differences were found for the assessment of subtle osseous changes ('J0' category: p = 0.041; 'J1' category: p = 0.018). Almost perfect intra- and interrater agreements were found for 'D' and 'L' categories (intrarater and interrater agreements for 'D': κ = 0.92 and κ = 0.84, respectively; intrarater and interrater agreements for 'L': κ = 0.93 and κ = 0.89, respectively). However, the assessment of 'J' categories revealed only moderate interrater agreement (κ = 0.49). The DLJ scoring system based upon MRI findings is feasible for routine clinical TMD assessment, and may help to simplify interdisciplinary communication between radiologists and clinicians.

Transitioning to chronic temporomandibular disorder pain: A combination of patient vulnerabilities and iatrogenesis

Background

Based on a variety of studies conducted in recent years, some of the factors that might contribute to the negative treatment responses of some TMD patients have been elucidated.

Methods

This paper describes known vulnerability factors that make individuals susceptible to developing temporomandibular disorders (TMDs), as well as those that contribute to the perpetuation of such problems. In addition, the topic of iatrogenesis is discussed as a major contributor to the negative outcomes that can be seen in this field.

Results

At the patient level, anatomical, psychosocial and genetic factors may contribute to individual vulnerability. The anatomy and pathophysiology of muscles, joints, disc and nerves may all be involved in predisposing to TMD symptoms, especially when the patients have pain elsewhere in the body. Among the psychosocial factors, some features may be elucidated by the DC/TMD axis II, while others (eg illness behaviour, Munchausen syndrome, lack of acceptance of non‐mechanical approaches) require careful evaluation by trained clinicians. Genetic predisposition to first onset TMDs and to chronification of symptoms has been identified for individuals with certain psychological traits, presence of comorbid conditions and certain abnormal clinical manifestations. Regarding iatrogenesis, sins of omission may influence the clinical picture, with the main ones being misdiagnosis and undertreatment. Joint repositioning strategies, occlusal modifications, abuse of oral appliances, use of diagnostic technologies, nocebo effect and complications with intracapsular treatments are the most frequent sins of commission that may contribute to chronification of TMDs. The patients who present with massive occlusal and jaw repositioning changes combined with persistent severe orofacial pain are not a rarity within TMD and orofacial pain canters; these patients are the most difficult ones to manage because of this horrific combination of negative factors.

Conclusions

The information presented in this paper will help clinicians to understand better why some individuals develop temporomandibular disorders, why some of them will progress to becoming chronic patients, and what the appropriate responses may be.

Management of temporomandibular joint disorders: A surgeon's perspective

Disorders of the Temporomandibular joint (TMJ) may clinically present with jaw pain and restricted mouth opening that may limit a patient's access to comprehensive dental care. The aim of this article is to provide a general overview of the current treatment strategies available in the management of disorders of the TMJ. Both conservative and surgical treatment options will be discussed as there is no one treatment for temporomandibular disorders (TMD) which encompasses a wide range of diagnoses. A multidisciplinary team approach to management is essential in the fundamental care of all TMD patients so that treatment can be specifically tailored to individual patient needs.

Scaffold-Based Temporomandibular Joint Tissue Regeneration in Experimental Animal Models: A Systematic Review

Reconstruction of degenerated temporomandibular joint (TMJ) structures remains a clinical challenge. Tissue engineering (TE) is a promising alternative to current treatment options, where the TMJ is either left without functional components, or replaced with autogenous, allogeneic, or synthetic grafts. The objective of this systematic review was to answer the focused question: in experimental animal models, does the implantation of biomaterial scaffolds loaded with cells and/or growth factors (GFs) enhance regeneration of the discal or osteochondral TMJ tissues, compared with scaffolds alone, without cells, or GFs? Following PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analysis) guidelines, electronic databases were searched for relevant controlled preclinical in vivo studies. Thirty studies reporting TMJ TE strategies in both small (rodents, rabbits; n = 25) and large animals (dogs, sheep, goats; n = 5) reporting histological and/or radiographic outcomes were included. Twelve studies reported ectopic (subcutaneous) implantation models in rodents, whereas 18 studies reported orthotopic, surgically induced defect models in large animals. On average, studies presented with an unclear-to-high risk of bias. In most studies, mesenchymal stem cells or chondrocytes were used in combination with either natural or synthetic polymer scaffolds, aiming for either TMJ disc or condyle regeneration. In summary, the overall preclinical evidence (ectopic [n = 6] and orthotopic TMJ models [n = 6]) indicate that addition of chondrogenic and/or osteogenic cells to biomaterial scaffolds enhances the potential for TMJ tissue regeneration. Standardization of animal models and quantitative outcome evaluations (biomechanical, biochemical, histomorphometric, and radiographic) in future studies, would allow more reliable comparisons and increase the validity of the results.

Correlation between pain and MRI findings in TMD patients

INTRODUCTION

Magnetic resonance imaging has been established as the gold standard for assessment of the temporomandibular joint. Apart from an excellent assessment of the soft tissues it has the advantage not to expose the patient to ionizing radiation. There is a lack of literature concerning the correlation between pain intensity and radiological findings of the temporomandibular joint. Moreover there is the question of whether a progressive degeneration of the cartilaginous components is accompanied by an increasing degeneration of the osseous parts of the mandibular joint and vice versa. Therefore, this study aims at analyzing correlations between pain and radiological findings. Furthermore, the link between osseous and cartilaginous degeneration is studied.

MATERIALS AND METHODS

91 patients who attend our outpatient clinic for temporomandibular disorders are included in this prospective study. Apart from a detailed anamnesis and clinical examination - adapted to the Research Diagnostic Criteria for Temporomandibular Disorders -magnetic resonance imaging of both mandibular joints is performed. Pain intensity is measured using the visual analog scale. To assess and grade the radiological findings a classification system is established. The evaluation of the osseous components is based on the classification of osteoarthritis by Kellgren and Lawrence whereas the rating of the cartilaginous components is adapted to the Research Diagnostic Criteria for Temporomandibular Disorders. Correlations are verified by Spearman-Rho.

RESULTS

83,5% of all patients are female. Most of the time, both sides are affected (47.25%). Women state an average pain of 5.7 (±2.4), men 3.5 (±2.5). 182 discs are examined and assessed with our classification system. Most discs (n = 71) show no pathological changes. The majority of patients show no dislocation (n = 104). The most common forms of dislocation are anterior dislocations (n = 51). The majority of patients show no changes in the osseous component (n = 115). Weak to moderate correlations are found between disc and bone degeneration. Moderate to strong correlations are found between left and right TMJ.

CONCLUSIONS

The classification system which is designed and applied during the study proves to be a reliable and practical Instrument. A standardized evaluation of pathologies concerning the temporomandibular joint is possible by using this system. Numerous patients attending our outpatient clinic do not show any signs of degenerative dysfunctions in the mandibular joints. Degenerations of the osseous components tend to be connected with degenerations of the cartilaginous components and vice versa. The question remains if in the future new procedures in imaging will be able to record pathologies not yet detected.

Temporomandibular Joint Surgery: What Does it Mean to India in the 21st Century?

While India boasts the largest collective experience in the surgical management of TMJ ankylosis, times are changing and Indian Surgeons will need to begin thinking about other TMJ disorders that have previously gone under the radar. A growing Indian middle class with greater access to health facilities will demand treatment for TMJ disorders like myofacial pain and dysfunction, internal derangement and osteoarthrosis which Oral & Maxillofacial Surgeons must be prepared to manage. The aim of this paper is to review the role of TMJ surgery and its place in the treatment armamentarium of temporomandibular disorders. Indications, rationale for surgery, risks vs benefits are discussed and complemented with examples of clinical cases treated by the author. As India moves up the economic ladder of success, TMJ disorders that have largely been confined to Western nations will begin to appear in the rising middle classes of India. Indian Oral & Maxillofacial Surgeons must be prepared to recognize and manage disorders which present with more complex symptomatology where the role of TMJ surgery is less clear cut.

Temporomandibular joint surgery: what does it mean to the dental practitioner?

A poor appreciation of the role of surgery in the management of temporomandibular disorders (TMD) may result in some patients being denied access to appropriate care. While surgery is often considered as an option of last resort, there are instances where surgery is the definitive and sometimes the only treatment option. The aim of this paper was to review the role of temporomandibular joint (TMJ) surgery and its place in the treatment armamentarium of temporomandibular disorders. Indications, rationale for surgery, risks vs. benefits are discussed and complemented with examples of clinical cases treated by the author. All dental practitioners should be aware of the benefits of TMJ surgery so that patients do not suffer unnecessarily from ongoing non-surgical treatments that ultimately prove to be ineffective in the management of their condition.

A biomechanical basis for primary arthroplasty of the temporomandibular joint

Biomechanical principles of temporomandibular joint (TMJ) loading are unique, particularly in an orthopedic system that exhibits curvilinear general plane motion. Certain type-specific derangements can be surgically challenging and may primarily require open arthrotomy techniques rather than arthroscopy. This article discusses the basic biomechanical principles in normal and pathologic function. Three-dimensional preoperative imaging of TMJs is necessary for appropriate assessment of all patients and when open techniques are necessary as the initial surgical procedure.

The role of surgery in the management of disorders of the temporomandibular joint: a critical review of the literature. Part 2

The literature is unequivocal in its support for surgery in the management of certain disorders of the Temporomandibular joint (TMJ). Unfortunately, the literature on TMJ surgery is based more on observation than science since randomised clinical trials comparing surgical treatment of the TMJ with medical treatment and no treatment (i.e., placebo) do not exist. Because the application of scientific principles in clinical studies which involve surgical intervention are ethically unfeasible, the true benefit of surgical intervention for Temporomandibular Disorders (TMD) may never be conclusively established. Waiting for properly designed, placebo controlled, random clinical trials will only impede the progress of surgical experience and frustrate the decision making for both clinicians and patients. Therefore, the current recommendations for surgery must rely on the best available evidence. The aim of this, the second of two papers, is to scrutinize the role of TMJ surgery in light of the controversies that have appeared in the literature in recent years.

The role of surgery in the management of disorders of the Temporomandibular Joint: a critical review of the literature. Part 1

Despite the controversy surrounding the role of surgery in the management of Temporomandibular Disorders (TMD), studies in peer review journals continue to support the role of surgery as a legitimate means of treating pain and dysfunction in the Temporomandibular Joint (TMJ). To better understand the role of surgery in the management of TMJ disorders, a critical review of the literature will be presented in two parts. Part 1 reviews the evolution of TMJ surgery together with the biological evidence for surgical disease. History teaches us that we are destined to repeat the mistakes of the past if we fail to properly reflect on what has already been achieved and where the failures have occurred. With the help of molecular biology, the future of TMD management may comprise more carefully targeted and less radical treatment modalities.

The interpositional dermis-fat graft in the management of temporomandibular joint ankylosis

The aim of this retrospective clinical study is to present the clinical experience of using dermis-fat interpositional grafts in the surgical management of temporomandibular joint (TMJ) ankylosis in adult patients. Eleven adult patients who presented with ankylosis of the TMJ were identified and included in the study. All patients underwent a TMJ gap arthroplasty which involved the removal of a segment of bone and fibrous tissue between the glenoid fossa and neck of the mandibular condyle. The resultant gap was filled with an autogenous dermis-fat graft procured from the patient's groin. All patients were followed up for a minimum of 2 years. Five of the 11 patients were found to have osseous ankylosis while 6 patients had fibro-osseous ankylosis. Two patients had bilateral TMJ ankylosis that were also treated with costochondral grafts which were overlaid with dermis-fat graft. The average interincisal opening was 15.6 mm on presentation which improved to an average of 35.7 mm following surgery. Patients were followed up from 2 to 6 years post-operatively (mean 41.5 months) with only 1 re-ankylosis identified out of the 13 joints treated. This study found that the use of the autogenous dermis-fat interpositional graft is an effective procedure for the prevention of re-ankylosis up to 6 years following the surgical release of TMJ ankylosis.

The prevalence of osteoarthrosis in cases of advanced internal derangement of the temporomandibular joint: a clinical, surgical and histological study

INTRODUCTION

The articular disk has a central role in the pathology of internal derangement of the Temporomandibular Joint (TMJ). What is less clear is the role of osteoarthrosis in the development of internal derangement. The aim of this study is to determine the prevalence of osteoarthrosis in cases of advanced and recalcitrant TMJ internal derangement that were treated by diskectomy.

MATERIALS AND METHODS

This study involved 22 joints in 18 patients who underwent surgery for the treatment of advanced and recalcitrant internal derangement of the TMJ. All patients included in the study failed to respond to at least 6 months of pre-operative conservative treatment and the clinical diagnoses of advanced TMJ internal derangement were confirmed on pre-operative MRI's. Tissue specimens were obtained from all 22 joints for histopathology. The specimens included articular disks that were excised from all 22 joints which were found to have severely displaced and deformed disks that were judged to be irreparable at the time of surgery. Also included were eight tissue samples from the mandibular condyles that were judged to be diseased on pre-operative tomograms and at the time of surgery. All samples were prepared in serial sections in the standard way and examined under light microscopy by two experienced Oral Pathologists.

RESULTS

There were 22 specimens of articular disk examined together with 8 specimens from the mandibular condyle. All 22 joints (100%) showed histological evidence of disk pathology and eight of the 22 joints (34.4%) were found to have condylar pathology. The most common disk pathology was hyalinization indicative of disk degeneration (12/22). The most common condylar pathology found was articular surface degeneration indicative of osteoarthrosis (8/22).

CONCLUSION

The clinical and radiological diagnoses of advanced TMJ internal derangement correlated with histological findings of degeneration and inflammation of the articular disk in all 22 specimens. The 8 specimens obtained from the condylar head showed histological features consistent with osteoarthrosis. This study showed that osteoarthrosis and internal derangement were found to co-exist in the same joint in about one-third of cases. The fact that osteoarthrosis was not found in all cases suggests that perhaps the widely held view that subclinical osteoarthrosis may lead to pathologic tissue responses in the form of internal derangement will need to be re-examined.

Evaluation of disc position in edentulous patients with complete dentures

OBJECTIVE

This study evaluated the condyle-disc relationship on magnetic resonance image (MRI) in a group of subjects with silent temporomandibular joints (TMJs) when tested clinically with those in subjects with discernible temporomandibular sounds. Study design Twenty-five completely edentulous patients were selected to participate in this study. The study was based on bilateral MRIs of 15 patients (with articular sound) and 10 symptom-free volunteers (control).

RESULTS

It was noted that disc displacement was found in 45% of the TMJs with no history of articular sounds. In 6 TMJs of control group, a reducing disc displacement was found, and in 3 TMJs a permanent displacement was found. Disc displacements were identified in 70% of patients. Reducing disc displacement was found in 19 of these TMJs, whereas permanent displacement was found in 2 TMJs. In 9 of the joints of the symptomatic group, a superior disc position was found. Also verified was a significant association between reducing disc displacement and biconvex disc.

CONCLUSION

These observations demonstrated that internal derangements can not be associated to clicking joints or symptoms of temporomandibular disorders in elderly edentulous patients, and the presence of displaced discs seems to be associated to altered disc morphology, but not to osseous abnormalities.

A review of 56 cases of chronic closed lock treated with temporomandibular joint arthroscopy

PURPOSE

The aims of this prospective clinical study were to look at the features that constitute chronic closed lock of the temporomandibular joint (TMJ) and to assess the effectiveness of TMJ arthroscopic lavage and lysis in the management of this condition.

PATIENTS AND MATERIALS

Sixty joints in 56 patients who presented with mandibular hypomobility suggestive of chronic closed lock were prospectively examined and treated with TMJ arthroscopic lavage and lysis during a 3-year period from 1996 to 1999.

RESULTS

Eighty-seven percent (49 of 56) of patients were found to have chronic closed lock of the TMJ. The most common intra-articular findings were fibrillation (76%) and synovitis (54%). TMJ arthroscopic lavage and lysis were found to be effective in the management of chronic closed lock in 84% (47 of 56) of patients, with an average 66% reduction in pain levels and a mean improvement of 9.8 mm in interincisal mouth opening up to 6 weeks after the procedure.

CONCLUSIONS

Chronic mandibular hypomobility is a clinical sign that is often but not always caused by chronic closed lock of the TMJ. The intra-articular findings of this study suggest that cartilage degradation and synovial inflammation are important components of chronic closed lock of the TMJ that respond well to arthroscopic lavage. Patients with mandibular hypomobility not caused by closed lock of the TMJ (ie, myofascial pain and dysfunction, osteoarthrosis, and others) are less likely to derive benefit from arthroscopic lavage and lysis, so other treatment methods should be considered.

The value of patient feedback in the audit of TMJ arthroscopy

AIM

This study assessed the patients' and clinicians' perception of the outcome of temporomandibular joint arthroscopy.

METHOD

All patients who underwent TMJ arthroscopy for both diagnostic and therapeutic purposes over a 6-year period were sent a questionnaire that asked about various symptoms attributable to the TMJ. Additionally a review of the clinical notes was performed.

RESULTS

83 patients underwent arthroscopy to 127 temporomandibular joints. The mean follow up was 3.6 years. 55% of patients assessed their jaw function as being effective, jaw movement, pain control, and overall satisfaction were satisfactory in 37%, 57%, and 48% of cases respectively. The clinicians' assessment revealed that 45% of patients had no joint tenderness, 74% of patients were able to open to > 35 mm and 74% of patients were free of any joint noise. 66% of patients were prepared to undergo a second procedure if indicated.

CONCLUSION

Overall, 50% of patients seemed to view arthroscopy favourably although many patients still felt that jaw opening was restricted. The outcome was not related to the position and reducibility of the disc at surgery and other variables may be responsible. The disparity between the clinical evaluation and the patients' perception of effectiveness emphasises the importance of patient feedback.

Mandibular height asymmetry following experimentally induced temporomandibular joint disk displacement in rabbits

OBJECTIVE

The purpose of this study was to test the hypothesis that nonreducing disk displacement of the temporomandibular joint causes mandibular asymmetry.

STUDY DESIGN

Unilateral anterior temporomandibular joint disk displacement with intact posterior disk attachment was surgically created in the right joints of seven growing rabbits. In each of seven sham animals, the right temporomandibular joint was surgically opened without any disk manipulation. Seven animals served as references. For identification of ramal growth and inferior growth at the mandibular base, tantalum implants were inserted into the mandibular body. Lateral cephalograms were exposed repeatedly throughout the 3-month investigation period. Kruskal-Wallis one-way analysis of variance was used to compare the groups.

RESULTS

Compared with the sham and reference groups, the experimental group exhibited a deviant growth pattern, with inferiorly directed growth along the mandibular base and in the gonial area. The ramal height was significantly shorter on the side with disk displacement. No significant side difference was present in the sham and reference groups.

CONCLUSIONS

Disk displacement can cause mandibular asymmetry in growing rabbits, including shortening of the mandibular ramus and excessive inferiorly directed bone growth along the lower border of the mandible.