Open Lock Research Articles

Internal derangements of the temporomandibular joint

An internal derangement of the temporomandibular joint is described as a deviation in the position or shape of the joint tissues. Such a change is only functionally manifest if it interferes with smooth movements of the jaw joint. There are a number of internal derangements associated with jaw movements in which popping jaw joint sounds can occur. Examples are an anteriorly or posteriorly displaced disc and hypermobility of the condylar head. Although most internal derangements are harmless and only cause minor discomfort to patients, disc displacements can in some cases develop into a clinical problem, for example when there is a limitation of mouth opening (so-called closed lock) or an inability to close the mouth (so-called open lock). Most patients with these conditions do not require any or only conservative treatment.

Asociación entre Hiperlaxitud Articular Generalizada y Chasquidos de la Articulación Témporo Mandibular

This study analyzes whether generalized joint hypermobility (GJH) is a risk factor for temporomandibular joint disorders (TMD). Therefore, we evaluated the potential association between TMD clicking and GJH diagnosis. We worked with the following hypothesis: patients with GJH would have a higher prevalence of TMJ clicking than those without it, making GJH a risk factor for joint disorders. Two hundred and fourteen students from the School of Dentistry of Universidad de la Republica del Uruguay (UdelaR) were examined: 161 female and 53 male, aged 18 to 30 (average age: 23.8 years, SD=2.7). Each participant was given a questionnaire, and a clinical examination was performed to diagnose GJH using the Beighton score (BS), clicking, history of maxillofacial trauma, orthodontics, full dentition, open lock, and shift. A calibrated blind researcher (kappa inter-rater click calibration = 0.68; intra-rater BS score=0.82, click=1) performed all the examinations. The Ethics Committee approved the study, and all the participants signed an informed consent. A multiple logistic regression model was used to analyze the data statistically. GJH prevalence was 34.16% in women and 7.55% in men; clicking prevalence was 24.22% in women and 11.32% in men. There was a significant association between sex (OR=3.244, p-value 0.018) and history of trauma (OR=2.478, p-value 0.041) and the presence of clicking. No association was found between clicking and GJH. Female sex and history of trauma could be risk factors for TMJ disorders. The lack of association between GJH and clicking in this age group (18-30) suggests that GJH may not be a risk factor for developing these pathologies.

Grant deadline: An escape room to simulate grant submissions

Background and purposePrevious lectures for graduate trainees did not convey the urgency, complexity, and challenges of a successful grant submission. To increase engagement, instructors applied gamification principles to create an educational escape room. Serious games used in other settings engage participants to solve problems, build teamwork, and improve communication skills. This study was designed to fill a gap in the types of educational training effectively conducted via escape rooms. Educational activity and settingA college of pharmacy team implemented a game to simulate the grant submission process and familiarize trainees to internal processes and resources. Participants searched for grant opportunities, identified proposal errors, solved research-related clues to open locks, contacted a difficult collaborator, physically located resources, and requested permission for late submission. The activity was implemented during an introductory class for first-year graduate students (n = 19). Learning objectives targeted the technical and relational aspects of proposals within a realistic, timed setting. Student perceptions of the escape room experience were gathered via individual interviews (n = 8) and evaluated by thematic analysis. FindingsAnalysis of participant emotions, thoughts, and attitudes identified common themes of excitement (63%), fun (50%), stress (38%), and frustration (25%). Compared to didactic instruction, many interviewed students preferred the escape room (63%) and found it conducive to learning (63%). A subset thought it might not work for everyone (13%) or would be improved by adding a didactic component (13%). SummaryThis escape room served as an engaging method to introduce graduate students to the grant submission process.

The use of occlusal splints in temporomandibular disorders - an overview.

Abstract Temporomandibular disorders (TMD) affect the temporomandibular joints, the masticatory muscles, and surrounding tissues. Among symptoms such as jumps, joint noises, reduced mouth opening (closed lock), difficulties in closing the mouth (subluxation or open lock), pain is the most common symptom encountered among patients diagnosed with temporomandibular disorders. As literature on this topic is abundant and sometimes controversial, the authors focus on reviewing the state of art of occlusal splints indications. Therefore, the most common occlusal splints, like Lucia jig, nociceptive trigeminal inhibition (NTI), directive splints, etc., are being described, based on their design and therapeutic indications. Cases of malocclusions associated or not with parafunctions are usually manageable using the splints mentioned in this article. In case of disc displacements, occlusal appliances can be used, but as the etiology is multifactorial, there are some limitations, depending on the complexity of each clinical situation.

A clinical-based protocol of diagnosis of temporomandibular joint open lock and treatment with arthrocentesis.

Arthrocentesis of the temporomandibular joint (TMJ) is a minimally invasive surgical procedure that provides good clinical results such as the improvement of jaw movements. It also helps to balance the synovial liquid viscosity and relieve TMJ pain by the washout of inflammatory components from the upper compartment. The purpose of this study is to report a case series of patients submitted to a clinical-based protocol of diagnosis of TMJ joint open lock and treatment with arthrocentesis. Patients suffering from a recurrent unilateral open lock of the TMJ were submitted to one arthrocentesis of the affected TMJ and all of them reported that the open lock was caused by daily stomatognathic activities. To decide the arthrocentesis as the initial treatment of these patients, the authors followed a rational protocol of diagnosis. Ten patients were included in the present study. No complications occurred during arthrocentesis. Immediately, 1week, 1month, and 6months after arthrocentesis, patients did not suffer from open lock or disc click anymore. They also reported no more pain because it was strictly related to the disc click. All patients of the present study improved from the open lock and disc click of the affected TMJ for 6months after arthrocentesis. The clinical-based protocol of diagnosis of TMJ open lock reported in the present study, followed by the treatment with arthrocentesis is a reasonable, low-cost, and safe method to treat patients with the acute open lock.

Using an “Escape Room” toolbox approach to enhance pharmacology education

Background: Faculty are encouraged to use a variety of teaching/learning strategies to engage nursing students. While simulation and games are now common, there were no reports in the nursing literature using an “escape room” concept. Escape rooms use an entertainment approach as teams engage in critical thinking to solve puzzles and find clues to escape a room. In the classroom setting, this concept is modified to solve a mystery by finding various objects through a series of puzzles to locate clues. Some of these games involve finding numerical clues to open locks on a box, such as a toolbox. The purpose of this study was to describe the use of a toolbox gaming strategy based on an escape room concept to help students learn about cardiovascular medications in a pharmacology course.Methods: This pilot study employed a descriptive qualitative method to investigate an approach to pharmacology education. The sample consisted of first semester nursing students.Results: Student responses to criteria-based questions resulted in three themes: engaging, teamwork, and frustration, related to using a toolbox scenario strategy as a pathway to learning.Conclusions: This descriptive study yielded mixed results from the students who were frustrated by time constraints but engaged in the learning experience. Lessons are offered for future improvements.

How muscle relaxation and laterotrusion resolve open locks of the temporomandibular joint. Forward dynamic 3D-modeling of the human masticatory system

Patients with symptomatic hypermobility of the temporomandibular joint report problems with the closing movement of their jaw. Some are even unable to close their mouth opening wide (open lock). Clinical experience suggests that relaxing the jaw muscles or performing a jaw movement to one side (laterotrusion) might be a solution. The aim of our study was to assess the potential of these strategies for resolving an open lock and we hypothesised that both strategies work equally well in resolving open locks. We assessed the interplay of muscle forces, joint reaction forces and their moments during closing of mouth, following maximal mouth opening. We used a 3D biomechanical model of the masticatory system with a joint shape and muscle orientation that predispose for an open lock. In a forward dynamics approach, the effect of relaxation and laterotrusion strategies was assessed. Performing a laterotrusion movement was predicted to release an open lock for a steeper anterior slope of the articular eminence than relaxing the jaw-closing muscles, herewith we rejected our hypothesis. Both strategies could provide a net jaw closing moment, but only the laterotrusion strategy was able to provide a net posterior force for steeper anterior slope angles. For both strategies, the temporalis muscle appeared pivotal to retrieve the mandibular condyles to the glenoid fossa, due to its’ more dorsally oriented working lines.

Manual Pigging with Improved Safety usingMicrocontroller based Passcode Lock

Pigging, the pipeline cleaning process in oil and gas industries is very risky. Pig, a line size plug is propelled in the pipeline to remove the scales and debris. So many fatal accidents happened so far during the removal of pig from the pipeline. Safety is very important than anything. This paper deals about providing a cost effective simple easily adaptable solution to avoid accidents during the removal of pig. A passcode open lock is provided at the closure for safety. The passcode will be generated using a microcontroller reading the safe conditions like position of the valves and pressure in the receiver using proximity and pressure sensors. The passcode will randomly change and will be displayed when the condition is safe. The closure cannot be opened without passcode. Thus we can improve the safety and avoid accidents.

A Novel Treatment of Recurrent Temporomandibular Joint Dislocation with Intermaxillary Fixation Using Microimplant: A Case Report

Dislocation of temporomandibular joint (TMJ) is troublesome condition which was most commonly shown far anteriorly displaced mandibular condyle to the articular eminence, thereby make it impossible to close one’s mouth. It is often referred to as ‘open lock’ in clinically. Although anatomical modification of the articular eminence through eminectomy has been considered most satisfactory and efffective treatment for managing the recurrent dislocation, it seldom performs clinically due to its invasiveness and patient’s reluctance. We thought a shortterm intermaxillary fixation could be of benefit to the patient suffering from recurrent dislocation. A 21-year-old male patient with recurrent TMJ dislocation which had developed after excessive mouth opening, was successfully treated with intermaxillay fixation using microimplant for 2 months. It is more conservative and less complicated method than eminectomy in treating recurrent TMJ dislocation. Transient intermaxillary fixation using microimplant and elastics could be one of treatment options for recurrent TMJ dislocation.

Case report of recurrent temporomandibular joint open lock associated with abrupt reduction of displaced articular disk

PatientThis report describes the case of a 51-year-old male patient who initially presented at age 23 with a habitual intermittent open lock (at >35mm) in the left temporomandibular joint (TMJ). The patient was able to manage this affliction through rapid-repetition jaw opening and closing. Tomography of the joint showed no irregular morphology, but intraoral examination revealed an occlusal interference at the mandibular left third molar during leftwards excursion. For this patient, alteration of lateral guidance using a palatal plate attached to the maxillary left canine precluded this intermittent open lock, but at 22 years of age, the open lock recurred and could not be relieved by the patient, who was unable to assume an occlusal position. Because conservative treatment was ineffective, a pumping manipulation technique was applied to reduce the open lock, after which the patient has maintained good jaw function. MRI taken before and after repositioning indicated that abrupt reduction of a displaced articular disk was the cause of the open lock, and that this articular disk was restored to its proper position during the manipulation. DiscussionMost TMJ open locks occur as anterior dislocation, where the mandibular head becomes trapped anterior to the articular eminences, causing excessive opening and difficulty closing. Our clinical findings from this patient indicate that open lock can occur through abrupt reduction of a displaced articular disk, particularly in patients with chronic internal derangement of the TMJ. ConclusionTMJ open lock can occur following abrupt reduction of a displaced articular disk.

Evaluating Container Ship Routes: A Case For Choosing Between The Panama Canal And The U.S. Land Bridge

For container traffic from the Far East to Europe, shipping routes and transportation choices are about to be taken to a new competitive level. Ship sizes have increased through time, yet the Panama Canal has remained unchanged, struggling to keep pace with larger size traffic. Over that same time span, more logistical pressure has been placed on the U.S. as a land bridge for container traffic from Asia to Europe. However, the canal is set to open new locks to accommodate today’s biggest container ships, creating more choices for container traffic to many eastern Atlantic ports. In our work, we investigate choices for container ship transportation from the eastern Pacific to the western Atlantic based solely on time. Choices include traveling through the Panama Canal or using the U.S. as a land bridge (via truck and rail car). A breakeven methodology, given vessel size, is employed to discriminate between paths. Implications for decision-making are then presented and discussed. Interested parties of our work might include those investigating multi-modal integration opportunities, those seeking transportation efficiencies in water, truck and rail, and students as a case assignment in Transportation and Logistics courses.

측두하악관절의 개구성 과두걸림 환자의 골격적 특성에 관한 연구

본 연구는 측두하악관절의 개구성 과두걸림과 골격적 특성 사이의 연관성을 분석하고자 개구성 과두걸림 환자를 대상으로 측두두부방사선 사진과 횡두개촬영 방사선 사진을 이용하여 두개골의 골격적 특성 및 관절 융기의 기울기를 비교 분석하였다. 개구성 과두걸림 환자를 환자군으로 하고 개구성 과두걸림은 없지만 측두하악장애 연구진단 기준(Research Diagnostic Criteria for Temporomandibular Disorder; RDC/TMD) Axis I에 따라 측두하악장애으로 진단된 환자를 측두하악장애 환자군, 개구성 과두걸림과 측두하악장애가 모두 없는 정상 환자를 정상군으로 설정하고 순차적으로 수집된 환자군 50명과 성별 및 연령이 일치하도록 무작위로 측두하악장애 환자군과 정상군, 각각 50명의 임상기록을 선별하였다. 측두하악장애에 영향을 줄 수 있는 관절염이나 외상의 병력, 악안면 기형, 악안면 수술 병력이 있는 환자는 모두 제외하였다. 세 군의 측두두부규격방사선 사진과 횡두개촬영 방사선 사진을 분석하여 골격적 특성과 관절 융기의 기울기를 측정하였다. 두개골과 하악과의 골격적 특성을 나타내는 측두두부방사선 사진을 분석한 결과 개구성 과두걸림이 있는 환자군에서 하악의 전후방적 위치를 나타내어주는 saddle angle이 더 작은 것으로 나타났으며 이는 두개골에 대해 하악이 더 전방으로 위치하고 있음을 나타낸다. 또한 횡두개촬영 방사선 사진상에서는 개구성 과두걸림 환자군이 측두하악장애 환자군과 정상군보다 관절융기의 기울기가 더 크게 관찰되었다. 이러한 결과는 두개골에 대해 측두하악관절이 더 전방으로 위치하고 관절 융기가 더 급한 경사를 가질 경우 개구성 과두걸림이 발생할 가능성이 더 크다는 것을 의미한다. This study was performed to investigate the skeletal factors related to open lock of the temporomandibular joint(TMJ). We compared the skeletal measurements on the cephalogram and transcranial radiograph among 3 groups, open lock group consisting of consecutively filed 50 patients with at least one open lock episode within recent 1 year, temporomandibular disorder(TMD) group of 50 TMD patients without open lock diagnosed by Research Diagnostic Criteria for TMD (RDC/TMD) Axis I, and normal group of 50 patients without TMD or open lock. The patients of TMD and normal group were randomly selected in an age-and-gender-matched way with ones of open lock group. Open lock group showed smaller saddle angle than normal group on cephalograms and steeper inclination of the articular eminence than TMD and normal groups on transcranial radiographs. These results imply that the patients with the joint located more anterior and the articular eminence with steeper inclination might be riskier to TMJ open lock.

Biomechanical modeling of open locks of the human temporomandibular joint

BackgroundPatients with hypermobility of the temporomandibular joint may have problems closing their mouth after opening widely. In the worst case, the mandibular condyles become trapped in front of the articular eminences and the jaw muscles cannot reposition them into the fossae (open lock). The difference in ease of closing the jaw between patients and non-patients is presently not well understood. MethodsWide opening and subsequent jaw closing were simulated with a biomechanical model in a forward dynamics approach. The effect of anterior slope angle and orientation of jaw-closing muscles on condylar travel was determined. FindingsThe mandibular condyles traveled anterior of the eminences and back into the fossae uneventfully with backwardly oriented jaw closers and eminences with a gentle anterior slope. However, combinations of relatively forward oriented jaw closers and a steep anterior slope caused the condyles to continue traveling anteriorly upon jaw-closing attempts, ending in an open lock position. InterpretationOur results indicate that for the masticatory system to reach an open lock, various unfavorable combinations of jaw-closer orientation and anterior slope angle exist within normal physiological ranges. These findings could be relevant for maxillofacial surgeons, both for the diagnostic process and for clinical decisions, regarding patients suffering from open locks.

Chronic dislocation of temporomandibular joint persisting for 6 months: a case report

J Korean Assoc Oral Maxillofac Surg 2012;38:305-9) Temporomandibular joint (TMJ) subluxation and dislocation are uncommon but very unpleasant and distressing conditions to patients. Subluxation of the TMJ is an excessively abnormal condylar excursion secondary to flaccidity and laxity of the capsule. When the condyle head excurses anterior to the eminence upon wide opening, it can return to the fossa by self-manipulation or non-surgical conservative reduction. Surgery is recommended if a complete dislocation, so-called open lock, occurs as a chronic or recurrent protracted condition that cannot be reduced voluntarily. A range of surgical procedures can be performed to limit condylar hypermobility inclusing soft tissue tethering, creation of articular obstacles, removal of mechanical blockade and augmentation of articular eminence using different kinds of grafts. In the present case, a 74-year-old woman was diagnosed with a chronic TMJ dislocation that had lasted for 6 months. Bilateral condylectomy was performed and the post-operative results were good without functional limitations or recurrence.

Prevalence of temporomandibular joint diseases diagnosed by magnetic resonance imagining

The aim of this study was to analyze the prevalence of internal derangement of the temporomandibular joint (TMJ) diagnosed by magnetic resonance imaging (MRI). The following data was evaluated: chief complaint, gender, age, side affected, diagnosis, joint clicking, mouth opening, dental prosthesis and presence of muscle disorders. The sample comprised 59 successive patients (118 TMJs), 46 females and 13 males; ages ranged from 14 to 92 years. All patients were examined from 2002 to 2006. Anterior disc displacement with reduction was the most common disorder (60 joints); anterior disc displacement without reduction appeared in 17 joints; TNJ effusion (25 joints); open lock (1 joint); TMJ osteoarthritis (8 joints) and no pathology in 7 cases. TMJ click was present in 27 and 32 had no clicking. There were associated muscle disorders in 22 cases. Mouth opening ranged from 10 to 61 mm; 24 patients were using some kind of dental prosthesis. The following conclusions are drawn: anterior disc displacement with reduction is the most common pathological condition in patients submitted to MRI; there is a marked predominance in women; and the presence of muscle pathology associated with intracapsular pathology is more prevalent in women.

Israeli Experience: From Arthroscopy Came Arthrocentesis, Why?

TMJ arthrocentesis, a non-arthroscopic lavage, is a “low-tech, high-prudence” modality that is highly efficient in particular types of TMJ disorders. Its effectiveness in some disorders and ineffectiveness in others has led to a refinement of our understanding of TMJ function and dysfunction. This relatively simple procedure, used following the failure of non-surgical treatment, dramatically decreases the need for invasive surgical interventions and their consequences. TMJ arthrocentesis is carried out under local anaesthesia, in sterile conditions by introducing Ringer solution using the same points of entry described by McCaine. The procedure is complemented by taking steps to reduce joint loading (eg rest, soft diet, medication, relaxation techniques to reduce bruxism, interocclusal appliances, etc) and by physical therapy (eg, increasing joint movement, and muscle strength and length). As opposed to surgical arthroscopy, arthrocentesis of the upper compartment is limited to force apart the flexible disc from the surface of the fossa/eminence and to wash away inflammatory products. It is therefore effective in overcoming painful states or limited movement (LMO) caused by inability of the disc to slide due to increased friction or adhesive forces. Arthrocentesis is not expected to be effective in those disorders caused by non-washable causes such as displacement of the disc, adhesions or osteophytes. Arthrocentesis is, for example, highly efficient for releasing anchored disc phenomenon where it neutralizes the adhesive forces and separates the flexible disc from the rigid surface of the eminence. However, it is markedly less efficient in LMO caused by non-reducible disc. Similarly, artrocentesis is efficient for elimination of ’open lock’ and intermittent clicking and is highly effective in neutralizing pain localized to the joint (arthragia), In osteoarthritis, arthrocentesis is highly efficient in both reducing pain and increasing the range of movement in about 70% of the patients referred for surgery. In the remaining 30%, it acts as a diagnostic tool indicating that the pain and/or limitation are caused by an unwashable cause, such as fibrous adhesions or osteophytes that are not always easy to diagnose by imaging. Following proper instruction, arthrocentesis can be performed in peripheral outpatient clinics. In addition, the procedure can be complemented by injecting medication suitable to the joint disorder. New products aiming to encourage free movement will be discussed.

Open Lock of the Jaw on Induction of Anesthesia: A case report

The temporomandibular joint can be dislocated during anesthesia as a result of excessive oral opening and direct laryngoscope handling. Occasionally, yawning can be observed during the induction of anesthesia with propofol. The forceful and voluntary yawning after a propofol injection can lead to a dislocation of the temporomandibular joint. We report a case of an anterior dislocation of the temporomandibular joint upon induction with propofol, which caused difficulties in mask ventilation and endotracheal intubation. Although intubation had been carried out successfully in this case, an unanticipated difficult airway can be confronted at anytime. Therefore, anesthesiologists should be aware of the management of a difficult airway and practice various methods according to a difficult airway algorithm.

Temporomandibular joint “open lock” versus condylar dislocation: Signs and symptoms, imaging, treatment, and pathogenesis

Purpose: In the temporomandibular joint (TMJ) “open-lock” condition the condyle is entrapped in front of the lagging disc and cannot slide back under the fossa. The aim of this retrospective study was to describe the signs and symptoms and imaging of TMJ “open lock” versus condylar dislocation and clarify its pathogenesis. The study stresses the efficacy of arthrocentesis in restoring the functional capacity of the joint, while obviating the need for surgical intervention. Patients and Methods: The study included 5 patients (3 females and 2 males; ages ranging from 11 to 26 years) presenting 6 open-lock joints that did not respond to conservative treatment. The TMJs postarthrocentesis status in 5 joints (follow-up period, 6 to 32 months) was determined by patient self-assessment and clinical examination. Results: Five TMJs had recurrent open lock and were treated by arthrocentesis. They reacted favorably to the treatment and the open-lock events were eliminated. The first case was apparently misdiagnosed as condylar dislocation, and unnecessary surgical intervention was performed. Conclusions: Arthrocentesis is a safe and rapid procedure that prevents recurrence of open-lock conditions. This disorder should be distinguished from recurrent condylar dislocation, which requires surgical intervention. © 2002 American Association of Oral and Maxillofacial Surgeons J Oral Maxillofac Surg 60:506-511, 2002

関節円板に由来する閉口末期の閉口障害

We report seven cases of mouth closing disturbance caused by the disc of the temporomandibular joint during the final phase of occlusion. The diagnosis was based on the results of magnetic resonance imaging or arthrographic imaging. Two of the seven patients had posterior disc displacement without reduction, while one had the same condition with reduction and the remaining four had posterior folding of the retrodiscal tissue.The patients with posterior disc displacement had a history of luxation, open lock, or both, suggesting that the mouth closing disturbance may have been caused by loosening of the lateral and medial attachments of the disc to the condyle as well as by excessive anterior movement of the condyle. The cases of posterior folding of the retrodiscal tissue were apparently related to anterior disc displacement. This condition, which was similar to the posterior open bite that occurs during anterior repositioning splint treatment for internal derangement, apparently occurred spontaneously.An important point in distinguishing between posterior folding of the retrodiscal tissue and posterior disc displacement is whether the patient has a past history of reciprocal clicking.

Clinical symptoms of open lock position of the condyle: Relation to anterior dislocation of the temporomandibular joint

Nine cases of open lock position of the condyle of the temporomandibular joint (TMJ) are reported. In two patients recurrent dislocation of the TMJ was diagnosed clinically, and four had previous episodes of anterior dislocation. An arthrotomographic examination revealed that the condyles of the affected TMJs were located anterior to the anterior bands of the disks at an open-mouth position. An arthrographic fluoroscopic examination showed that the anterior bands mechanically obstructed the anteriorly displaced condyles from posterior movement into the articular fossae to various degrees at open-mouth position. One cause of anterior dislocation of the TMJ is thought to be fixation of the condyle in the open lock position resulting from a disturbance of a neuromuscular mechanism. In the two patients with dislocation, occlusal treatment eliminated muscular symptoms and the dislocations completely disappeared.