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Condylar resorption

Condylar resorption, also known as idiopathic condylar resorption (ICR), is a condition characterized by the progressive breakdown and loss of bone in the mandibular condyle, the rounded end of the lower jaw that forms part of the temporomandibular joint (TMJ).^[1] This resorption leads to a reduction in condylar height, resulting in mandibular retrognathia (rearward displacement of the lower jaw), clockwise rotation of the mandible, and often an anterior open bite, which can alter facial aesthetics and cause functional impairments such as difficulty chewing.^[2] It primarily affects the TMJ and is most commonly observed in adolescent and young adult females, with a female-to-male ratio of approximately 9:1, typically occurring during puberty between the ages of 10 and 20.^[3]^[1] The etiology of condylar resorption remains incompletely understood but is thought to involve a combination of hormonal and mechanical factors that disrupt the adaptive capacity of the TMJ.^[2] Hormonal influences, particularly elevated estrogen levels during puberty, may promote excessive remodeling or hyperplastic changes in the synovial tissues of the joint, leading to bone loss.^[3] Other potential contributors include trauma, orthodontic treatment, or orthognathic surgery, though many cases are idiopathic with no identifiable trigger; the condition may self-limit in some patients but can recur or progress if untreated.^[3] Clinically, it presents with symptoms such as TMJ pain, headaches, limited jaw mobility, and progressive malocclusion, including class II occlusion and facial asymmetry in unilateral cases, while about 25% of patients may be asymptomatic initially.^[1]^[3] Diagnosis relies on a combination of clinical evaluation, patient history, and advanced imaging to confirm active resorption and rule out other TMJ disorders.^[2] Key diagnostic tools include cephalometric radiographs, computed tomography (CT), cone-beam CT (CBCT), magnetic resonance imaging (MRI) to assess disc position and synovial proliferation, and bone scans to detect ongoing metabolic activity, often requiring serial imaging over 6–12 months to monitor progression.^[3]^[2] Treatment strategies vary based on severity and patient age, starting with conservative approaches like anti-inflammatory medications, occlusal splints, and orthodontics to stabilize occlusion and alleviate pain.^[1] For advanced cases, surgical interventions are often necessary, including condylectomy (removal of the resorbed condyle) with reconstruction using costochondral grafts or alloplastic TMJ prostheses, frequently combined with orthognathic surgery for functional and aesthetic correction; recent advancements emphasize 3D planning and disc repositioning techniques for improved outcomes.^[2] Recovery from surgical treatments typically spans 6–12 weeks, with high success rates in reducing pain and stabilizing the jaw when performed by experienced specialists.^[1]

Background

Definition and Synonyms

Condylar resorption is defined as a progressive, pathologic loss of bone from the mandibular condyle, primarily affecting the temporomandibular joint (TMJ) and resulting in alterations to occlusion and facial morphology.^[4] This condition involves the breakdown and resorption of the condylar head, leading to a reduction in condylar height and posterior facial shortening.^[5] It is distinct from other TMJ disorders due to its specific degenerative process targeting the condylar bone.^[1] Common synonyms for condylar resorption include idiopathic condylar resorption (ICR) and condylysis. ICR refers to the most prevalent subtype, characterized by no identifiable underlying cause, often manifesting in adolescents and young adults.^[3] Condylysis describes the same resorptive phenomenon, emphasizing the localized destruction akin to a lytic process in the condyle.^[6] Condylar resorption was first reported in the medical literature by Burke in 1961, initially described as acquired condylar hypoplasia.^[7] The idiopathic form gained recognition as a distinct entity in orthodontic and maxillofacial literature during the 1990s, notably through the work of Arnett and Tamborello in 1990, which highlighted its progressive nature and clinical implications.^[8]

Epidemiology

Condylar resorption is a rare condition characterized by progressive loss of the mandibular condyle, with inadequate global data available due to frequent underdiagnosis and limited population-based studies. A 2024 scoping review of idiopathic condylar resorption (ICR) in adolescents emphasized the scarcity of research on its true prevalence, noting that existing evidence is primarily derived from specialized cohorts such as orthodontic or temporomandibular disorder (TMD) patients rather than general populations.^[8] In orthodontic patients, estimated incidence rates range from 1% to 31%, particularly elevated among those with Class II malocclusions or undergoing orthognathic surgery.^[4] Demographically, condylar resorption disproportionately affects females, with a reported female-to-male ratio of 9:1 to 16:1, and predominantly occurs in adolescents and young adults aged 10 to 30 years.^[9] The condition peaks during puberty, aligning with its idiopathic nature and potential influences from growth-related factors.^[10] There is no strong evidence of geographic or ethnic variations in condylar resorption, though it is more commonly documented in populations pursuing orthognathic treatment, where higher female prevalence may relate to hormonal profiles.^[11] Recent 2024 analyses of post-orthognathic surgery cohorts indicate increased recognition of the condition, with incidence rates around 9.5% overall and up to 31% in high-risk subgroups, where resorption contributes to relapse in affected cases.^[12]^[4]

Anatomy and Pathophysiology

Temporomandibular Joint Structure

The temporomandibular joint (TMJ) is a ginglymoarthrodial joint, classified as a synovial diarthrosis, that connects the mandibular condyle to the glenoid fossa of the temporal bone. This complex structure allows for both hinge-like rotation and gliding translation, facilitating essential functions such as mastication, speech, and yawning. The joint capsule encloses the articulation, containing a synovial cavity lined by a synovial membrane that produces lubricating fluid, while an articular disc divides the cavity into superior and inferior compartments. Key stabilizing ligaments include the temporomandibular ligament, which limits excessive translation, as well as the sphenomandibular, stylomandibular, and collateral ligaments that anchor the disc to the condyle and fossa.^[13] The mandibular condyle forms the inferior component of the TMJ, presenting a rounded, oval-shaped articular surface measuring approximately 15-20 mm transversely and 8-10 mm anteroposteriorly. This surface is covered by a layer of fibrocartilage rather than hyaline cartilage, adapting to the compressive and shear forces of jaw movement. The condyle's vascular supply primarily derives from branches of the maxillary artery (including the masseteric and deep temporal arteries) and the superficial temporal artery, providing both periosteal and endosteal perfusion.^[13]^[14] In terms of biomechanics, the condyle enables critical mandibular movements, including protrusion for forward jaw positioning and lateral excursions for side-to-side grinding. Histologically, the condylar head is largely avascular in its articular zone, relying on diffusion of nutrients from the synovial fluid for cartilage maintenance, which makes it sensitive to disruptions in joint lubrication. Beneath the fibrocartilaginous surface lies the subchondral bone, a trabecular network that undergoes continuous remodeling in response to mechanical loads, balancing resorption and formation to preserve structural integrity. This adaptive capacity is particularly evident during development, where the condyle grows through endochondral ossification—a process involving chondrocyte proliferation, hypertrophy, and replacement by bone—remaining active through adolescence to accommodate mandibular expansion and alignment changes. This prolonged growth phase underscores the condyle's vulnerability in younger individuals to factors influencing remodeling dynamics.^[13]^[15]

Mechanisms of Resorption

Condylar resorption is characterized by osteoclastic hyperactivity that drives subchondral bone resorption, leading to progressive thinning of the condylar head and subsequent posterior rotation of the mandible.^[16] This process begins with the activation of osteoclasts in the synovial tissue and subchondral region, where they degrade bone matrix through acid secretion and enzymatic activity, resulting in loss of condylar volume and altered mandibular morphology.^[16] Chondrocytes under mechanical compression, such as from insufficient occlusal support, secrete tumor necrosis factor-alpha (TNFα), which promotes synovial osteoclastogenesis and amplifies bone resorption.^[16] Several theories explain the underlying mechanisms. Hormonal influences have been hypothesized, particularly the role of estrogen in enhancing osteoclast activity in females aged 14 to 50, with conflicting theories involving either elevated levels during puberty or deficiency; however, systematic reviews have found no direct evidence supporting these associations.^[17]^[18] Mechanical overload is a prominent theory, where excessive compressive or shear stresses on the temporomandibular joint (TMJ), often from clenching, orthodontic forces, or surgical advancements exceeding 5-10 mm, disrupt the balance between bone formation and resorption, favoring osteoclastic dominance.^[19]^[20] Avascular necrosis has also been proposed as a contributing factor, involving compression of retrodiscal blood vessels that compromises condylar perfusion and triggers ischemic bone loss, akin to mechanisms in other joints.^[4]^[21] Histopathological examination reveals features distinct from osteoarthritis, including severe irregular disruption of the fibrocartilage surface starting at the anterior pole, progressive degeneration without pannus formation or synovial hyperplasia, and absence of typical inflammatory infiltrates in the subchondral bone and synovium.^[22] Recent 2024 studies confirm this non-inflammatory profile in idiopathic cases, with cartilage degeneration leading to total condylar resorption up to the sigmoid notch, contrasting with the low-grade inflammation and broader subchondral changes seen in osteoarthritis. Recent 2025 studies, including finite element models of abnormal mechanical stress and scoping reviews of animal models, further support the role of biomechanical factors in progressive condylar resorption.^[22]^[23]^[24]^[25] The condition progresses in distinct stages. The active phase involves rapid resorption over 1 to 5 years, marked by ongoing osteoclastic activity, condylar mass reduction, and clinical signs like open bite development, often confirmed by elevated uptake on technetium-99m bone scans.^[7] This transitions to a quiescent phase, where resorption stabilizes, the condyle recorticate, and no further progression occurs, typically after 1 to 2 years of inactivity, though reactivation is possible before age 40.^[7] Biomechanical models illustrate how altered stress distribution contributes to resorption. Finite element analyses show that excessive loads, such as those from mandibular advancement or jaw opening, concentrate compressive and shear forces on the anterior condylar surface, exceeding adaptive thresholds and promoting localized bone loss without uniform remodeling.^[26]^[27] These models predict higher resorption risk with posteriorly inclined condylar necks or counterclockwise rotations, where peak stresses reach 0.3-170 MPa in the condylar region, disrupting the TMJ's load-bearing equilibrium.^[28]^[29]

Clinical Features

Symptoms

Patients with condylar resorption often report temporomandibular joint (TMJ) pain, which can be unilateral or bilateral and is typically exacerbated by activities such as chewing or yawning. This pain is present in approximately 75% of cases, often described as a moderate discomfort with an intensity of 3-4 out of 10, and may involve the masticatory muscles.^[5] Headaches, frequently of a temporomandibular or tension-type nature, are also common subjective complaints, affecting a notable subset of patients alongside TMJ discomfort.^[30] Additionally, ear pain or otalgia without evidence of infection is frequently reported, manifesting as aching around the ear due to referred pain from the TMJ.^[31] Functional symptoms include difficulty in mouth opening, with many patients experiencing a limited range of less than 35 mm, leading to challenges in daily activities like eating. Jaw fatigue is another prevalent issue, occurring in about 75% of affected individuals and contributing to overall masticatory inefficiency. Progressive malocclusion symptoms, such as an inability to bite properly or maintain occlusion, arise as the condition advances, often resulting in bite changes that patients perceive as worsening over time. These functional limitations are commonly linked to observable signs like an anterior open bite. Esthetic concerns are particularly noted by adolescent patients, who may describe a perceived facial asymmetry or a "clocking" appearance resulting from mandibular setback and reduced posterior facial height. This subjective dissatisfaction with facial profile changes can impact self-esteem during growth phases. The onset of symptoms is typically insidious, occurring during the pubertal growth spurt around age 12, with active resorption phases in the early stages often featuring more prominent pain before it stabilizes or diminishes.^[32] The progression varies but generally involves gradual worsening of functional and esthetic issues over months to years.^[5]

Physical Signs

Physical signs of condylar resorption primarily manifest through observable alterations in occlusion, facial structure, and temporomandibular joint (TMJ) function, often confirmed via clinical examination and cephalometric analysis. Occlusal changes are prominent, including the development of an anterior open bite and progression to a Class II malocclusion, resulting from the loss of condylar height and subsequent clockwise rotation of the mandible.^[5] This height reduction leads to posterior extrusion of maxillary teeth and increased overjet, with bilateral cases showing symmetric open bite and unilateral cases exhibiting midline shifts, crossbites, or uneven posterior wear.^[33] Cephalometric measurements typically reveal a steeper mandibular plane angle and Class II skeletal tendencies.^[32] Facial morphology is affected by mandibular setback, presenting as retrognathia, chin recession, and a "bird-face" deformity due to decreased posterior facial height.^[33] In bilateral resorption, the mandible appears retruded with a high gonial angle, while unilateral involvement may cause facial asymmetry and vertical discrepancies at the mandibular border.^[5] During TMJ examination, tenderness may be elicited on palpation of the preauricular area or condyle in approximately 25% of cases, alongside joint sounds such as clicking or popping in up to 75%.^[32] Reduced lateral excursion and mandibular deviation on opening are common, with maximum mouth opening often limited to around 35 mm.^[32] Associated signs include morphological features like condylar flattening and reduced condylar dimensions, with affected condyles showing decreased height (mean 12.6 mm) and width (mean 14.1 mm) compared to unaffected joints.^[32] These changes correlate briefly with reported symptoms such as pain but are primarily objective findings.^[33]

Etiology

Idiopathic Factors

Idiopathic condylar resorption (ICR) is defined as the progressive loss of mandibular condylar bone and cartilage in the absence of any identifiable systemic disease, trauma, or other secondary etiology. It constitutes the majority of condylar resorption cases, where no precipitating event can be pinpointed.^[34] Hormonal influences, particularly estrogen levels during puberty, have been theorized to play a role in ICR pathogenesis among females, who comprise the predominant demographic, though a 2025 systematic review found no conclusive evidence linking estrogen fluctuations to ICR.^[35] Decreased estrogen levels have been proposed to promote osteoclastogenesis by increasing receptor activator of nuclear factor kappa-B ligand (RANKL) expression in the temporomandibular joint (TMJ), thereby accelerating bone resorption.^[35] Some patients exhibit associated menstrual irregularities, with studies reporting that up to 96% of women with severe ICR show either low 17β-estradiol levels or highly irregular cycles, suggesting a potential link between hormonal imbalance and condylar remodeling.^[36] Genetic predisposition is hypothesized as a contributing factor in ICR, potentially involving polygenic influences that interact with environmental triggers, though no specific genes or mutations have been conclusively identified. Familial clustering remains rare, with only isolated reports of multiple affected relatives in otherwise sporadic cases.^[37] Autoimmune hypotheses propose that subclinical inflammation or dysregulated immune responses within the TMJ synovium may drive localized resorption in ICR, independent of systemic autoimmune disorders. Recent histopathologic analyses reveal distinct features in ICR, including severe fibrocartilage degeneration and subchondral bone remodeling without significant inflammatory infiltrates, contrasting sharply with the synovial inflammation and pannus formation observed in rheumatoid arthritis or juvenile idiopathic arthritis. This differentiation underscores ICR as a unique degenerative process rather than an autoimmune-mediated condition.^[22]

Secondary Causes

Secondary causes of condylar resorption encompass identifiable extrinsic factors that precipitate or exacerbate bone loss in the mandibular condyle of the temporomandibular joint (TMJ). These differ from idiopathic forms through clinical history revealing precipitating events or underlying conditions, allowing differentiation based on temporal associations or systemic involvement.^[3] Orthodontic and orthognathic procedures represent a prominent secondary cause, particularly in young females undergoing bimaxillary surgery. Condylar resorption occurs in 1-31% of cases following orthognathic surgery overall, with rates of 1.4-31% specifically after bimaxillary procedures, and a female-to-male ratio of approximately 5:1 highlighting heightened vulnerability in young women. High condylar strain from rigid internal fixation or excessive mandibular setback exceeding 6 mm contributes to this risk, as these factors increase mechanical overload on the condyle during postsurgical adaptation.^[11] Inflammatory arthritides, such as rheumatoid arthritis and psoriatic arthritis, frequently involve the TMJ and induce erosive changes leading to condylar resorption. In rheumatoid arthritis, TMJ involvement affects 20-40% of patients, manifesting as erosive synovitis that progressively resorbs the condyle, often detected via imaging despite being asymptomatic in many cases. Psoriatic arthritis similarly promotes destructive erosions in the TMJ, with up to 33% of patients experiencing joint symptoms and potential ankylosis from severe bone loss. Reactive arthritis can also target the TMJ, causing localized inflammatory resorption akin to these patterns.^[38] Trauma and parafunctional habits impose mechanical stress that overloads the TMJ, triggering resorption through direct injury or chronic wear. Condylar fractures from head or neck trauma directly damage the joint, potentially leading to avascular necrosis and subsequent bone loss if blood supply is compromised. Chronic parafunctional habits like bruxism exacerbate this by generating excessive occlusal forces, contributing to TMJ osteoarthritis and condylar resorption via sustained overload and tissue degeneration.^[3]^[39] Systemic conditions, including connective tissue disorders and hormonal imbalances, can accelerate condylar bone loss by altering joint stability or metabolic processes. Ehlers-Danlos syndrome, characterized by connective tissue fragility, increases TMJ disorder risk through hypermobility and recurrent dislocations, indirectly promoting resorption from instability-induced stress. Hyperparathyroidism elevates parathyroid hormone levels, which correlate with enhanced bone resorption in TMD patients, potentially worsening condylar erosion amid generalized skeletal demineralization.^[40]^[41]

Diagnosis

Clinical Evaluation

Clinical evaluation of condylar resorption begins with a detailed patient history to identify the onset, progression, and associated risk factors. The condition typically presents with a progressive worsening of occlusion and facial aesthetics over months to years, often during pubertal growth spurt between ages 10 and 20, with a strong predilection for adolescent females.^[42] Risk factors include recent orthodontic treatment, high mandibular plane angles greater than 35 degrees, and preexisting class II skeletal relationships, which may exacerbate the resorptive process.^[43] Symptom progression commonly involves increasing overjet, development of an anterior open bite, and posterior mandibular rotation, potentially accompanied by temporomandibular joint (TMJ) pain, clicking, or dysfunction, though up to 25% of cases may be asymptomatic.^[42] Patients or guardians often report noticeable chin retrusion or bite deterioration, sometimes linked to high-impact activities like cheerleading in young females.^[3] The physical examination protocol integrates intraoral, extraoral, and functional assessments to detect signs suggestive of condylar resorption. Intraorally, clinicians evaluate for class II malocclusion, anterior open bite exceeding 2 mm, and dental midline deviations in unilateral cases, using articulated dental casts for serial comparison.^[43] Extraorally, attention focuses on facial asymmetry, mandibular retrognathia, and increased lower facial height due to clockwise rotation.^[42] Functional tests include measuring maximal interincisal opening, which may be limited to less than 40 mm, and assessing for lateral deviation or deflection on mouth opening, along with protrusive and lateral excursions typically reduced to less than 7 mm.^[3] For TMJ pain evaluation, standardized questionnaires based on the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) are employed to quantify pain intensity and location, aiding in distinguishing resorptive changes from primary myofascial or arthritic pain.^[44] Differential diagnosis considerations are essential to exclude mimicking conditions through targeted history elements. Juvenile idiopathic arthritis (JIA) is ruled out by inquiring about systemic symptoms, polyarticular involvement, or elevated inflammatory markers, as it often affects multiple joints unlike the TMJ-predominant resorption.^[45] Tumors or infections are differentiated by their rapid onset without pubertal correlation and absence of progressive occlusal shifts over months.^[3] Osteoarthritis or reactive arthritis post-trauma is less likely in adolescents under 20 without joint space narrowing history or other joint affections.^[45] Staging condylar resorption as active or inactive relies on serial clinical measurements to guide management timing. Active disease is indicated by progressive changes such as overjet increase exceeding 2 mm or condylar height reduction over 6-12 months, often confirmed clinically via repeated dental casts and photographs.^[42] Inactive staging occurs after 1-5 years of stabilization without further progression, though reactivation risk persists with joint loading; confirmation may involve brief imaging correlation but emphasizes longitudinal clinical tracking.^[7]

Imaging Techniques

Conventional radiography, particularly panoramic radiographs, serves as an initial screening tool for assessing condylar morphology in cases of suspected resorption. These images can reveal gross changes such as erosion, flattening, and decreased ramus height on the anterior, superior, and posterior condylar surfaces, though they are limited by distortion and overlapping structures that hinder precise evaluation of medial or lateral aspects.^[3]^[5]^[46] Advanced imaging modalities provide more detailed assessment of both bony and soft tissue involvement. Cone-beam computed tomography (CBCT) is particularly valuable for three-dimensional evaluation of bone structure, allowing comprehensive visualization of all condylar surfaces and quantification of volume loss to distinguish pathologic resorption from physiologic remodeling.^[5]^[46] It offers high-resolution reconstructions with lower radiation exposure compared to traditional CT, making it suitable for serial imaging to track progression.^[5] Magnetic resonance imaging (MRI) excels in evaluating soft tissue components, including disc displacement, synovial hyperplasia, and joint effusion associated with resorption. Standard protocols using T1-, T2-, and proton density-weighted sequences achieve high accuracy (up to 95%) in determining disc position and detecting early degenerative changes like condylar volume reduction.^[46] Dynamic contrast-enhanced MRI further assesses activity by revealing enhanced perfusion in adjacent masticatory muscles, such as the lateral pterygoid, which correlates with severe resorption severity.^[47] Bone scintigraphy, using technetium-99m, can detect increased metabolic activity in the condyles indicative of active resorption, aiding in staging the disease, though serial scans over 6-12 months may be needed for confirmation and it has limited specificity for isolating condylar resorption from other TMJ pathologies.^[3] Cephalometric analysis using lateral skull radiographs quantifies skeletal alterations resulting from condylar resorption, such as reduced posterior ramus height (often <35 mm preoperatively in at-risk cases) and an increased mandibular plane angle (typically >40-49 degrees in affected individuals). These measurements help identify associated features like mandibular retrognathism and Class II malocclusion, integrating objective imaging data with clinical findings for comprehensive diagnosis.^[48]^[5]^[49]

Management

Conservative Approaches

Conservative approaches to managing condylar resorption focus on alleviating symptoms, reducing temporomandibular joint (TMJ) loading, and potentially halting disease progression in early or mild cases, particularly during the active phase. These strategies are typically recommended as first-line interventions, especially for adolescents and young adults where idiopathic condylar resorption (ICR) is prevalent, aiming to stabilize the occlusion and minimize further bone loss without invasive procedures. A 2021 study using three-dimensional morphological analysis emphasizes stabilization splint therapy for reducing bone destruction and promoting condylar modeling in ICR patients.^[50] A 2024 scoping review on idiopathic condylar resorption in adolescents also supports conservative management, including splint therapy, to control symptoms and avoid interventions that may accelerate resorption during the active phase.^[8] Occlusal splints, particularly stabilization splints made of hard acrylic, are widely used to reposition the mandible, reduce joint stress, and protect against parafunctional habits like bruxism; they are typically worn at night to allow for an open bite accommodation. These devices unload the condyle by promoting a more centered position, which can alleviate pain and muscle tenderness in up to 70% of temporomandibular disorder (TMD) cases, including those with ICR features. In a study of 84 patients with ICR, stabilization splint therapy in 42 patients showed no significant condylar volume change and greater anabolic modeling tendency compared to conventional therapy over at least 6 months, with improvements in joint morphology observed via cone-beam computed tomography imaging.^[50] For adolescents, evidence supports splints as effective in managing active-phase symptoms, though adaptation may take weeks and regular adjustments are necessary. Orthodontic management employs camouflage techniques to address occlusal discrepancies without exacerbating resorption, such as intruding posterior teeth or using temporary anchorage devices (TADs) to achieve counterclockwise mandibular rotation and improve facial esthetics. These approaches avoid mandibular advancement during active resorption to prevent increased condylar strain, focusing instead on stabilizing the bite once the disease stabilizes. A 2022 study of 19 cases reported an average 2.27° counterclockwise rotation, enhancing condylar unloading and function.^[51] Such interventions are most effective post-splint therapy to ensure joint stability before tooth movement.^[52] Pharmacotherapy targets inflammation and pain associated with ICR-related TMD, with nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen serving as the initial choice to reduce synovial irritation and muscle spasm. These agents provide symptomatic relief in the majority of TMD patients, including those with condylar involvement, by inhibiting prostaglandin synthesis and are often combined with splints for synergistic effects. Corticosteroids may be considered for short-term use in cases with significant inflammation, though evidence is stronger for juvenile idiopathic arthritis-related resorption than pure idiopathic forms; the 2015 AAFP review on TMD highlights NSAIDs as first-line for acute pain relief. Occlusal equilibration, a non-pharmacologic adjunct, balances occlusal forces to further minimize joint load.^[53] Lifestyle modifications complement other conservative measures by reducing mechanical and psychological stressors on the TMJ, including adoption of a soft diet to limit chewing forces and promote joint rest. Patients are advised to avoid hard or chewy foods, opting for items like soups and mashed vegetables, which can decrease condylar strain and support remodeling in growing individuals. Behavior changes, such as stress reduction techniques (e.g., mindfulness or biofeedback), address potential psychosocial contributors to parafunction, with studies linking lower stress to improved TMD outcomes. If conservative strategies fail to control progression after 6-12 months, transition to surgical options may be warranted.^[52]

Surgical Interventions

Surgical interventions for condylar resorption are reserved for advanced cases where conservative measures fail to halt progression or restore function, focusing on skeletal correction, joint decompression, or replacement to address severe deformities and pain. Orthognathic surgery, typically involving bimaxillary procedures with counterclockwise rotation of the maxillomandibular complex, aims to correct anteroposterior and vertical discrepancies resulting from condylar loss. However, when performed during the active phase of resorption, these procedures exhibit high relapse rates due to ongoing bone remodeling and condylar instability. To mitigate this, surgery is delayed until disease quiescence is confirmed via serial imaging, such as cone-beam computed tomography, demonstrating no further resorption over 12-24 months. A 2025 study analyzing 200 patients reported a 9.5% incidence of post-surgical condylar resorption, emphasizing risk factors like high mandibular plane angle for prediction and tailored interventions.^[12] Temporomandibular joint (TMJ)-specific procedures target intra-articular pathology to provide mechanical relief and potentially slow resorption. Arthrocentesis involves irrigation and lysis of adhesions through needle access, while arthroscopy allows direct visualization for lavage, debridement, and release of disc-capsular attachments, with success rates up to 85% in reducing pain and improving mouth opening in TMJ disorders associated with resorption. Disc repositioning surgery stabilizes the articular disc to its anatomic position using sutures or anchors, promoting condylar remodeling and growth in adolescent cases, particularly when combined with functional orthotics. Eminectomy, resection of the articular eminence, offers relief from disc displacement or recurrent locking by increasing translational space, though it is less commonly applied in pure resorption without dislocation. For end-stage condylar resorption with bone loss exceeding 50%, total joint replacement (TJR) using custom alloplastic prostheses replaces the dysfunctional condyle and glenoid fossa, providing stable reconstruction without reliance on remaining native bone. Literature indicates low skeletal relapse rates under 5% with these prostheses, attributed to their biomechanical design and lack of biological resorption, though complications such as infection (incidence 2-5%) and hardware loosening require vigilant postoperative monitoring. Prior to any surgical intervention, a trial of conservative approaches, including splint therapy and occlusal adjustment, is essential to assess disease stability. Combined approaches integrate orthognathic surgery with TMJ procedures, such as disc repositioning or TJR, to simultaneously address skeletal and joint pathology for optimal functional and aesthetic outcomes. Recent literature highlights the importance of patient selection through risk factor analysis, including mandibular plane angle and preoperative orthodontics duration, to predict resorption risk and tailor interventions when performed in quiescence.

Prognosis

Long-term Outcomes

The natural history of idiopathic condylar resorption (ICR) involves an active phase of progressive condylar bone loss, typically lasting 6 to 24 months, after which the condition often becomes self-limiting with stabilization occurring in the majority of cases during early adulthood.^[54]^[55] Untreated ICR leads to permanent skeletal alterations, including mandibular retrognathia, anterior open bite, and reduced ramus height, with resorption rates averaging 1.5 mm per year during the active period.^[3]^[5] Treatment outcomes vary by approach, with conservative management, such as occlusal splints and orthodontic therapy, achieving symptom improvement and disease stabilization in many cases based on small studies, particularly when initiated during or shortly after the active phase.^[56] Surgical interventions demonstrate higher long-term stability; orthognathic surgery alone has relapse rates around 45% in some studies, while combined temporomandibular joint replacement (TJR) shows high stability in reported cases, based on follow-up periods averaging 6 years.^[56] Follow-up involves serial imaging, such as panoramic radiographs or cone-beam computed tomography, and occlusal records every 6-12 months to monitor progression and stability.^[56] Favorable prognostic factors include early diagnosis during the active phase, treatment in female patients post-puberty (the primary demographic affected), and confirmation of disease quiescence prior to definitive intervention.^[56] Treatment often leads to improved quality of life, with systematic reviews reporting significant functional and psychological benefits in the long term.^[57]

Complications

Condylar resorption can lead to progressive facial asymmetry due to uneven bone loss in the mandibular condyles, resulting in a receding chin and imbalanced appearance.^[3] This condition often causes chronic temporomandibular joint (TMJ) dysfunction, manifesting as persistent pain, limited jaw mobility, and masticatory difficulties.^[1] In adolescents, particularly young females, the resultant alterations in facial aesthetics can have a significant psychological impact, including diminished body image and reduced quality of life.^[58] Furthermore, the degenerative process increases the risk of secondary osteoarthritis in the TMJ, characterized by cartilage erosion and subchondral bone changes.^[59] Surgical management of condylar resorption carries specific risks, including inferior alveolar nerve injury, which occurs in approximately 5-10% of cases involving orthognathic procedures, potentially leading to persistent sensory deficits in the lower lip and chin.^[60] In total joint replacement (TJR) for advanced resorption, infection rates range from 2-5%, often necessitating prosthesis removal and prolonged antibiotic therapy.^[57] Hardware failure, such as loosening or fracture of implants, is another concern, contributing to the need for reoperation in affected patients.^[61] Conservative treatments, like occlusal splints, may fail if not properly adapted, potentially exacerbating parafunctional habits and accelerating resorption progression.^[56] Condylar resorption occurs in approximately 9.5% of patients following orthognathic surgery, with higher incidence in mandibular advancement cases linked to condylar overload and volume loss exceeding 15%.^[12] In advanced resorption scenarios, non-union of surgical sites can occur, complicating healing and requiring additional interventions.^[62] Long-term challenges include the need for revisions in 10-15% of TJR cases, driven by ongoing degeneration or device-related issues.^[63] Recent 2024 histopathologic studies demonstrate irreversible cartilage loss in idiopathic condylar resorption, with severe fibrocartilage degeneration and subchondral bone remodeling that precludes full restoration.^[64]

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The joint is enclosed by a capsule and contains a synovial cavity and articular cartilage. Synovial fluid and several ligaments are present within the joint.
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Vascularization of the mandibular condylar head with respect to ...
Results: The main source of condylar head vascularization is the inferior alveolar artery, supplying bone marrow of the whole mandible as well as its cortical ...Missing: vascular | Show results with:vascular
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Arterial Vascularization of the Mandibular Condyle and Fractures of ...
In this study, the arteries that consistently led to the condyle were the superficial temporal artery, the deep posterior temporal artery, and arterial branches ...
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Evolution and development of the mammalian jaw joint
This review describes the evolution of the novel mammalian novel jaw joint (temporomandibular joint [TMJ]) in the fossil record and the development of the TMJ ...
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Synovial osteoclastogenesis mediated by chondrocyte-secreted ...
May 8, 2024 · Synovial osteoclastogenesis mediated by chondrocyte-secreted TNFα promotes TMJ condylar resorption. Oral Dis. 2024 Nov;30(8):5140-5153. doi ...Missing: histopathology | Show results with:histopathology
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Condylar resorption after orthognathic surgery: A systematic review
The aim of this systematic review was to discuss the physiopathology, mechanisms, risk factors, diagnosis and treatment of this disease.
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Is oestrogen associated with mandibular condylar resorption? A ...
A systematic review of the literature was performed regarding the influence of oestrogen on the occurrence of mandibular condylar resorption.
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Condylar Resorption Following Compressive Mechanical Stress in ...
The aim of this experimental study was to evaluate the mechanism of influence of condylar resorption on compressive mechanical stress in temporomandibular ...Missing: review | Show results with:review
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Overloaded Orthopedic Force Induces Condylar Subchondral Bone ...
Appropriate orthopedic force led to bone remodeling of mandibular condyle, while overloaded orthopedic force (OOF) induced condylar bone absorption.Missing: review | Show results with:review
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Avascular necrosis of the mandibular condyle-pathogenesis and ...
Chuong and colleagues [10,11] postulated that the mechanism of condylar resorption was similar to that of avascular necrosis of the femoral head.
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https://pubmed.ncbi.nlm.nih.gov/39476870/
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Histopathology of Idiopathic Condylar Resorption Differs ... - PubMed
Idiopathic condylar resorption (ICR) is a rare condition of unknown etiology characterized by progressive decrease in volume and pathologic remodeling.
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Condylar Resorption Following Compressive Mechanical Stress in ...
Sep 3, 2022 · The aim of this experimental study was to evaluate the mechanism of influence of condylar resorption on compressive mechanical stress in temporomandibular ...Missing: biomechanical distribution
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Effect of jaw opening on the stress pattern in a normal human ...
Jun 19, 2014 · Excessive compressive and shear stresses are likely related to condylar resorption and disc perforation. Few studies have reported the disc ...
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Effects of condylar neck inclination and counterclockwise rotation on ...
Stresses of the temporomandibular joint increase with the counterclockwise rotation of the maxilla-mandibular complex. The posteriorly inclined neck should be ...<|control11|><|separator|>
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A Critical Review of Human Jaw Biomechanical Modeling - MDPI
The stress values were in the range of 0.3–170 MPa, whereas the deformation was in the range of 0.32–0.71 mm, with its peaks in the condylar region. After the ...
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Adolescent internal condylar resorption (AICR) of the ... - PubMed
Nov 10, 2017 · Clinical and imaging presentation: The condition usually occurs bilaterally with: (1) Progressive retrusion of the mandible; (2) High occlusal ...
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Idiopathic Condylar Resorption: TMJ, Symptoms, Causes, Treatment ...
Symptoms: Affected individuals may have symptoms such as pain or discomfort in the jaw, headaches, or difficulty opening or closing the mouth. These symptoms ...
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Signs, Symptoms, and Morphological Features of Idiopathic ... - NIH
Mar 11, 2022 · We performed a survey-based study on ICR in orthodontic patients and described its subjective symptoms, clinical signs, and condylar morphological features.
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Diagnosis and management of idiopathic condylar Resorption - NIH
These symptoms include malocclusion in general, followed by open bite, TMJ pain, myofascial pain, headaches, decreased mouth opening, and TMJ clicking, with an ...
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Relationship Between Estrogen and Idiopathic Mandibular Condylar ...
Jan 23, 2025 · Condylar resorption is a serious degenerative disease of the TMJ bony structures that occurs when the morphology of the articular heads changes, ...
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Oral contraceptive pill use and abnormal menstrual cycles in women ...
Twenty-six of the 27 women with severe condylar resorption had either laboratory findings of low 17β-estradiol or a history of extremely irregular menstrual ...
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(PDF) Idiopathic condylar resorption: The current understanding in ...
Aug 7, 2025 · The etiology is not completely understood, but it is considered as multifactorial with both genetic and environmental factors involved. The ...
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Comprehensive Management of Rheumatic Diseases Affecting the ...
The purpose of this review is to highlight the rheumatic conditions likely to affect the TMJ and outline medical and surgical management in these patients.
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Association of malocclusion, self-reported bruxism and chewing ...
TMJ-OA resulting from functional overloading can cause joint tissue collapse and condylar resorption, resulting in morphological changes of TMJs and then a ...
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Temporomandibular disorders among Ehlers-Danlos syndromes
Apr 11, 2024 · This narrative review aims to demonstrate and summarize the complex relationship between Ehlers-Danlos syndromes (EDS) and temporomandibular disorders (TMD)
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Biochemical changes associated with temporomandibular disorders
Nov 22, 2018 · In patients with temporomandibular disorders, increased parathyroid hormone levels in response to vitamin D deficiency was significantly more prominent.
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https://pmc.ncbi.nlm.nih.gov/articles/PMC11010766/
[41]
https://pmc.ncbi.nlm.nih.gov/articles/PMC6381509/
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Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) for ...
Condylysis/idiopathic condylar resorption. D ... [7/28/2013];Diagnostic Criteria for Temporomandibular Disorders (DC/TMD): Diagnostic Decision Tree.
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https://doi.org/10.1186/s40510-015-0115-8
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Imaging of the temporomandibular joint: An update - PubMed Central
Many different imaging modalities are currently used to evaluate the TMJ. Magnetic resonance imaging is commonly used for evaluation of the TMJ.
[45]
Dynamic contrast-enhanced magnetic resonance imaging of ... - NIH
May 14, 2025 · The chi-square test was conducted to determine differences in sex proportions and TMJ laterality between different condylar morphology groups. ...
[46]
Diagnosis and management of condylar resorption - PubMed
This article discusses the cause, appropriate diagnostic evaluation, and management of progressive condylar resorption.Missing: history differential
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Non-surgical risk factors for condylar resorption after orthognathic ...
The preoperative mandibular plane angle in Group I (mean value: 49.4 degrees ) was significantly greater (p=0.005) than in Group II (mean value: 44.9 degrees ).Missing: increased cephalometrics
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https://pubmed.ncbi.nlm.nih.gov/9024346/
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https://pubmed.ncbi.nlm.nih.gov/14980592/
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https://doi.org/10.1111/joor.13154
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https://doi.org/10.1111/ocr.12623
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Diagnosis and Treatment of Temporomandibular Disorders - AAFP
Mar 15, 2015 · TMD is classified as intra-articular or extra-articular. Common symptoms include jaw pain or dysfunction, earache, headache, and facial pain.
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[PDF] Idiopathic condylar resorption: a systematic review of etiology and ...
ICR is considered a self-limiting process, with disease duration of 6 months to 2 years.50. If the disease is quiescent and enough condylar mass remains ...
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Idiopathic Condylar Resorption: Evaluation and Treatment
Jun 13, 2015 · In patients with juvenile idiopathic arthritis (JIA), a current treatment approach is to minimize articular bone loss by using pharmacologic ...
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Current Status of the Management of Idiopathic Condylar Resorption ...
Jul 5, 2024 · This article provides an overview of the options presently reported in the literature to reduce its TMJ symptoms and improve mandibular function and form.Missing: quiescent | Show results with:quiescent
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A 2 year follow-up self-controlled study on morphological changes in ...
May 13, 2025 · Conservative treatment of CHF displayed significant musculoskeletal resorption. Clinical assessments showed less optimal improvements.3d Reconstruction Of The... · The Disc-Condyle... · Condylar Volume Analysis<|separator|>
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Functional, physical and psychosocial impact of degenerative ...
Dec 4, 2021 · This study evaluated the functional, physical and psychosocial impacts of TMJ degenerative joint disease (DJD).
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Osteoarthritis, Osteoarthrosis, and Idiopathic Condylar Resorption
The term “idiopathic condylar resorption,” also known as “progressive condylar resorption,” is described as a dysfunctional remodeling of the TMJ manifested by ...
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Inferior alveolar nerve injury following orthognathic surgery
There is no generally accepted, standard method of estimating sensory disturbances in the distribution of the inferior alveolar nerve following injury.
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Quality of Life Outcomes Following Total Temporomandibular Joint ...
Jul 9, 2025 · This systematic review demonstrates that total temporomandibular joint replacement (TMJR) is a highly effective, safe, and durable treatment for ...
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Indications for replacement after alloplastic temporomandibular joint ...
Infection is fortunately an uncommon complication of TMJR with one large cohort study reporting an incidence rate of 1.51% for PJIs at a mean of six months post ...
[62]
[PDF] Orthognathic surgery for patients with idiopathic condylar resorption
Dec 19, 2017 · An open bite tends to recur after treatment. According to a study by Denision et al., two-jaw surgery has low rates of open bite relapse and ...Missing: interventions | Show results with:interventions
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Reasons for failure of total temporomandibular joint replacement
The global revision rate was 1.19 per 100 prosthesis-years. The most common reason for revision was heterotopic bone formation. Stock prostheses appeared to ...
[64]
Temporomandibular Joint Prosthesis Revision and/or Replacement ...
May 19, 2020 · The incidence of TMJR revision (keeping the same device) was 3% and that of replacement (placing a new device) was 4.9%. The most common reason ...
[65]
Histopathology of Idiopathic Condylar Resorption Differs From ...
Oct 10, 2024 · Idiopathic condylar resorption (ICR) is a rare condition of unknown etiology characterized by progressive decrease in volume and pathologic remodeling.