Temporomandibular Joint Gap Arthroplasty in Cats

Comparison of Surgical Techniques for Correction of Mandibular Asymmetry in TMJ Ankylosis Patients

Background

Temporomandibular joint (TMJ) ankylosis frequently results in mandibular asymmetry, which impairs an affected person's ability to function and look good. Because of the intricacy of TMJ ankylosis and the variety of surgical procedures available, correcting mandibular asymmetry surgically can be difficult.

Methods

Patients with mandibular asymmetry and TMJ ankylosis who had surgery at a tertiary care facility between certain periods were the subject of a retrospective investigation. Medical records were used to gather information on patient demographics, pre-operative imaging, surgical methods, and post-operative results. Surgical methods included condylectomy with or without reconstruction, joint reconstruction with or without orthognathic surgery, and unilateral or bilateral mandibular distraction osteogenesis (MDO). Occlusion, patient-reported results, and facial symmetry made up the evaluation criteria.

Findings

The study had a total of 50 patients, with different surgical method distributions. Comparing unilateral and bilateral MDO to condylectomy and joint reconstruction, notable gains in face symmetry and occlusion were seen. The largest complication rate was seen with condylectomy, mostly from recurrence and device-related issues, albeit the rates of other procedures varied as well.

Conclusion

In conclusion, customized treatment planning is necessary for the correction of mandibular asymmetry in individuals with TMJ ankylosis. Although mandibular distraction osteogenesis produces better results for occlusion and facial symmetry, it is crucial to carefully weigh the risks involved. While still feasible treatments, condylectomy and joint reconstruction require strict monitoring for any consequences. In order to enhance patient care in this difficult patient group, future research should concentrate on improving treatment procedures and long-term results.

In-house three-dimensional printing for surgical planning: learning curve from a case series of temporomandibular joint and related disorders

Three-dimensional (3D) printed models can improve the understanding of the structural anatomic changes in cases of temporomandibular joint ankylosis and pseudoankylosis leading to closed jaw locking. Their use in pre-surgical planning and intraoperative guidance has been reported, contributing to the predictability and success of these surgery procedures, which can be quite complex, especially in small animal patients. The use and production of 3D tools and models remain challenging and are so far limited to institutions with high (economical and human) resources. This study aims to propose simplified workflows using open-source software to facilitate an in-house 3D printing process. To illustrate this, three cases of temporomandibular joint ankylosis and one of pseudoankylosis were reviewed, where in-house 3D printed models were used for client communication and surgical management. The 3D models were segmented from computed tomography and printed via stereolithography. They were used to support discussion with clients (n = 4), to allow surgeons to pre-surgical plan and practice (n = 4) and for intraoperative guidance during surgery (n = 2). Surgical cutting guides were produced in one case to improve precision and define more accurately osteotomy lines. It is essential to consider the initial time and financial investment required for establishing an in-house 3D printing production, particularly when there is a need to produce biocompatible tools, such as surgical cutting guides. However, efficient and streamlined workflows encourage the integration of this technology, by accelerating the printing process and reducing the steep learning curves, while open-source software enhances accessibility to these resources.

Repair and remodeling of the mandibular head of the condylar process in four immature dogs

Spontaneous repair and remodeling of the mandibular head of the condylar process is a rarely reported outcome following condylectomy. This clinical report describes the spontaneous repair and subsequent remodeling of the mandibular head of the condylar process in four immature dogs that sustained traumatic injuries, necessitating surgical intervention through arthroplasty via partial or complete condylectomy, or caudal mandibulectomy. In subsequent evaluations, it was observed that all dogs exhibited clinically functional TMJs, as evidenced by an appropriate range of motion. These findings were corroborated by the owners' reports of the patient's normal eating and drinking abilities. Conventional and cone-beam computed tomography studies demonstrated the repair and remodeling of the osseous tissues of the mandibular head of the condylar process. Histopathology was unavailable to assess the novel tissues. No evidence of intraarticular or extraarticular ankylosis or osteoarthritic changes was observed.

Etiology, clinical presentation, and outcome of temporomandibular joint luxation in cats: 21 cases (2000-2018)

This study was performed to report etiology, clinical presentation, treatment, and outcome of temporomandibular joint (TMJ) luxation in 21 cats (2000-2018). TMJ luxation was diagnosed by either dental radiography or computed tomography (CT). Causes for TMJ luxation included altercation with a dog (38%), hit-by-car (19%), unknown (19%), fall (19%), and ran into inanimate object (5%). The most common complication was development of permanent malocclusion (24%), followed by reduced vertical mandibular range of motion (5%). Reduction of TMJ luxation was successful in 94.7% of the cases. Reduction of the TMJ luxation was significantly associated with time from injury to treatment. No other significant associations were observed between cause of injury, type of TMJ stabilization, and outcome. TMJ luxation in cats carries an excellent prognosis with early joint reduction and supportive care. Concurrent dental trauma and maxillofacial injuries are common, and all patients with head trauma must be stabilized and evaluated with a thorough examination.

Caudal and middle segmental mandibulectomies for the treatment of unilateral temporomandibular joint ankylosis in cats

Case series summary

Three cats affected by unilateral temporomandibular joint ankylosis underwent segmental mandibulectomy, while one cat with bilateral ankylosis underwent right temporomandibular joint gap arthroplasty and left segmental mandibulectomy. Minimal intraoperative complications were linked to the segmental mandibulectomies in the cases reported. All cats recovered their ability to open the mouth, and the vertical range of motion was unaltered during the postoperative period. Mandibular drift and dental malocclusion were the main postoperative complications related to the segmental mandibulectomies.

Relevance and novel information

Surgical excision of ankylotic tissue at the temporomandibular joint region may be technically challenging and associated with severe iatrogenic trauma of surrounding tissues. The results of this case series suggest that middle or caudal segmental mandibulectomy is a safe, feasible and effective surgical procedure to treat unilateral temporomandibular ankylosis in cats and could be considered as an alternative surgical technique to surgical excision of ankylotic tissue at the temporomandibular joint.

Comparative Multimodal Palliative efficacy of gabapentin and tramadol By Using Two Pain Scoring Systems in Cats Undergoing Ovariohysterectomy

The analgesic efficacy of the gabapentin-tramadol combination was compared with meloxicam-tramadol and tramadol perioperative analgesic regimens in cats brought to the clinic for ovariohysterectomy. Thirty adult cats belonging to comparable demographics (age, body weight), were enrolled into a randomized, blinded study after due consent from their owners into four treatment groups. A Gabapentin-Tramadol group (GT-group, n = 10), Meloxicam-Tramadol group (MT-group, n = 10), and a Tramadol group (T-group, n = 10) were formed. Gabapentin capsules at 50 mg were administered orally 2 hours before surgery while the rest received a placebo dose. Tramadol (2 mg/kg, IM) and meloxicam at (0.2 mg/kg, SC) were injected immediately prior to anesthetic premedication. Anesthetic protocol involved premedication with ketamine and xylazine, while anesthesia was induced using propofol. Inhalant isoflurane anesthesia was used to maintain a surgical plane. GT group scored lower on IVAS as well as CPS than MT group, and T group for up to 8 hours after surgery. The mechanical nociceptive threshold remained higher (98±0) for up to 12 hours postoperatively a nd serum cortisol concentrations remained significantly lower during the 24hr period. The addition of gabapentin to the tramadol regimen significantly improved analgesia and mechanical nociceptive threshold than when used on its own.

Comparison of unilateral rostral, middle and caudal segmental mandibulectomies as an alternative treatment for unilateral temporomandibular joint ankylosis in cats: an ex vivo study

OBJECTIVES

Temporomandibular joint ankylosis (TMJA) is the partial or complete inability to open the mouth due to intra- or extra-articular fibrous, bony or fibro-osseous tissue proliferation. Surgical procedures such as gap arthroplasty, condylectomy or wide extra-articular osteotomy have been recommended to treat this condition; these techniques are challenging, time-consuming and have been occasionally associated with postoperative recurrence, severe periarticular neurovascular iatrogenic trauma and death. Segmental mandibulectomy had previously been recommended as an alternative option for unilateral TMJA, but the location of mandibulectomy and extent of bone removal from the mandible region have not been mentioned in the literature. This study aimed to validate the area of the mandibular body (rostral, middle or caudal) and amount of bony tissue that should be osteotomized during a segmental mandibulectomy for treatment of unilateral TMJA in cats.

METHODS

In this block study, 30 cadaver heads of domestic shorthair cats were randomly divided into three groups of 10 specimens each based on the mandibular region that would undergo segmental mandibulectomy (rostral, middle and caudal). The size of the removed mandibular segment and pre- and postoperative vertical range of mandibular motion were compared for statistical purposes.

RESULTS

A significant statistical difference was observed between the pre- and postoperative vertical range of mandibular motion between the rostral, middle and caudal segmental mandibulectomies (P <0.001). The mean postoperative recovered range of mandibular motion for the rostral, middle and caudal segmental mandibulectomies was 50.4%, 81.9% and 90.4%, respectively.

CONCLUSIONS AND RELEVANCE

The caudal segmental mandibulectomy showed the highest postoperative vertical range of mandibular motion. The removal of a minimum of 1.2 cm of the caudal mandibular body was required to achieve nearly full recovery of presurgical mouth opening in the specimens of this study. The caudal segmental mandibulectomy may eliminate the risk of iatrogenic periarticular neurovascular damage inherent to more invasive surgeries performed at the temporomandibular joint area. When performed unilaterally, the caudal segmental mandibulectomy is a viable surgical alternative that may show a similar outcome to other surgical techniques.

Management of Septic Arthritis of the Temporomandibular Joint in Dogs

Septic arthritis of the temporomandibular joint (TMJ) in dogs and other mammals is a rare condition. It is typically associated with notable pain, swelling, and difficulty in opening the mouth. Unlike degenerative TMJ disease, septic arthritis requires urgent intervention. The etiology of the condition may include penetrating trauma, an extension of local infection, such as otitis media, or the hematogenous spread of a pathogen. However, the precise cause may not always be identified. Diagnostic imaging with Computed Tomography (CT), cone-beam CT (CBCT), and/or Magnetic Resonance Imaging (MRI) are helpful for honing the definitive diagnosis and formulating a treatment plan. Subsequently, exploratory surgery may be required to obtain samples for culture and sensitivity and histology and to lavage the joint. In this “methods” article, we provide a detailed description of our approach to diagnosis and management of septic TMJ arthritis in four dogs.