Computerized Occlusal Analysis in Occlusal Splint Therapy

Functional occlusal patterns during lateral excursions in young adults

The aim of the study was measuring the effect of experimental jaw muscle pain on number and position of posterior occlusal contacts. Eleven adult voluntary subjects were enrolled. A lower impression was taken for each subject and two dental casts were obtained from each impression. The study was carried out in a randomised cross-over fashion. Each subject participated in two experimental sessions (30-day interval) in which he/she received an injection in the central part of the right masseter muscle consisting of 0·5 mL of either hypertonic or isotonic saline. Each subject was asked to rate pain intensity on a visual analogue scale. Three occlusal bite checks (polyvinylsiloxane) at the maximal intercuspal position were obtained during the experimental session: the first before the injection, the second between 60 and 90 s after the injection and the third 15 min after the injection. Evaluation of contacts was performed on dental casts with the use of different colours (black for baseline, red for intermediate and green for final contacts). Repeated-measures analysis of variance was used to compare the overall number of contacts among groups and the number of contacts of different colours. No significant difference was found between the overall number of occlusal contacts (P>0·05), but significant differences were found between contacts according to different colours: confirmed (P=0·006), disappeared (P=0·007) and new (P<0·001). Assuming different colours as change in contact position, the overall number of contacts did not change, but the position did. Experimentally induced jaw muscle pain affected the pattern of posterior occlusal contacts.

summary The effect of balancing‐side occlusal contact patterns on ipsilateral TMJ dynamics was evaluated in this study. Vertical displacement of the balancing‐side lower second molar during clenching at canine edge‐to‐edge position, with 0 and 1 mm of inter‐canine distance, was measured for 42 normal subjects in relation to their balancing‐side occlusal contact. Balancing‐side occlusal contact was classified into four following patterns; (1) simultaneous balancing‐side and working‐side contact (without clenching); (2) balancing‐side contact (with clenching only); (3) no balancing‐side contact (with or without clenching); and (4) exclusive balancing‐side contact (no working‐side contact). The vertical displacement of the balancing‐side condyle, calculated from the displacement of the balancing‐side second molar, showed three different types of displacement pattern. These three types showed distinctive incidence in relation to the pattern of balancing‐side occlusal contact. It was revealed that balancing‐side occlusal contact can affect the ipsilateral TMJ dynamics.

ABSTRACTBackgroundImplant‐supported prostheses frequently face both mechanical and biological challenges. Although various techniques and principles are employed to manage excessive loads, occlusal contacts often change within 6 months of placement.ObjectiveThis review aims to analyse relevant studies to evaluate the changes in occlusal contacts that occur following the placement of superstructures in implant‐supported prostheses.MethodsThe protocol was designed according to the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses Protocols (PRISMA‐P) and registered with the International Prospective Register of Systematic Reviews. Studies were included if their outcomes addressed stress distribution, occlusal force, occlusal contact, occlusal scheme or changes in occlusal time. Non‐English articles, case reports, animal experiments, systematic reviews and literature reviews were excluded.ResultsA total of 1867 articles were retrieved through database searches, along with an additional 43 articles identified through manual searches, of which 416 were duplicates. After screening the titles and abstracts, 1367 articles were excluded, and 12 were deemed non‐retrievable. The full texts of the remaining 85 articles were independently reviewed by two authors for eligibility, resulting in the exclusion of 77 articles based on the inclusion criteria. Ultimately, eight articles were included in the review.ConclusionImplant‐supported crowns gradually approach or surpass the load of natural teeth over time, as evidenced by increased occlusal force, larger contact areas and longer occlusion durations. These findings highlight the need for more accurate and advanced measurement techniques to better understand and manage the long‐term changes in occlusion associated with implant‐supported crowns.Trial RegistrationPROSPERO: CRD42024527043

BACKGROUND: Among the adult socially active population, one of the most common pathologies of the maxillary system is musculoskeletal dysfunction of the temporomandibular joint (TMJ). One of the modern methods of correction and treatment of TMJ dysfunction is splint therapy, which involves the use of splints and permits to consistently and selectively act on a particular level of disorders: occlusive, muscular, articular. This ultimately forms a new myostatic reflex of holding the jaw, builds physiological biomechanics and neuromuscular activity of the speech apparatus and the stomatognathic system as a whole. AIM: To prove the positive effectiveness of the use of splint therapy from the point of view of physiological concepts in optimizing the neuro- and myofunctional state of the stomatognathic system with an analysis of the effectiveness of the mode of using occlusal splints in patients with TMJ dysfunction. MATERIALS AND METHODS: The treatment was carried out in 34 patients with diagnosed TMJ dysfunction at the age from 17 to 40 years. For the treatment of patients, a relaxing therapeutic and diagnostic articular splint was used. The patients were divided into 2 groups of 17 people each: for the first group of patients, a round-the-clock mode of wearing a splint was set, for the second group, a 16-hour mode was set. The total observation period was 6 months. The criteria for achieving therapeutic goals were considered: absence/reduction of pain in the TMJ and orofacial pain, absence of pain on palpation of the masticatory muscles and in the TMJ, stable position of the lower jaw in the central occlusion, stability and uniformity of movements of the lower jaw at various functional positions, comfort when chewing and at rest, absence/reduction of hypertonicity of the masticatory muscles. RESULTS: The treatment results were evaluated 3 and 6 months after the primary stabilization of the mandible position. At the same time, among the patients of the first group, primary stabilization was achieved on average at the third visit (after 1.5 months from the start of splint therapy), in the second group of patients only at the fourth or fifth visit (after 2–2.5 months). Three months later, all patients of the first group and 8 patients from the second group noted a decrease in pain and orofacial pain, as well as the absence of pain on palpation of muscles and TMJ. Chewing discomfort was observed in 4 patients from the first group and 7 from the second. According to the results after 6 months, all patients were satisfied according to all criteria, all established objective criteria for treatment goals were achieved. CONCLUSIONS: With the correct selection of patients with symptoms indicative of muscle or occlusive dysfunction, splint therapy shows itself as an effective method that allows, with a full understanding of the biomechanics and functional physiology of the occlusal-muscular-articular complex, to effectively correct the neuromuscular state of the stomatognathic system towards it full balance.

Masticatory efficiency in complete denture and single implant-retained mandibular overdenture wearers with different occlusion schemes: A randomized clinical trial

The clinical and radiologic findings in 30 patients who sustained injuries to the temporomandibular joint (TMJ) were retrospectively analyzed. Imaging consisted of variable combinations of radiography, tomography, two-compartment arthrography, computed tomography, and magnetic resonance imaging and was performed 2 days to 24 months after injury. Indications for imaging included acquired and/or unstable occlusal disturbances, cephalalgia, facial pain, otalgia, TMJ pain, tinnitus, dizziness, hearing disturbance, masticatory dysfunction, and muscle atrophy. Radiologic findings included internal derangement of the TMJ meniscus, swelling of retrodiskal tissues, joint effusion, mandibular condyle and condylar neck fractures, osteochondritis dissecans, avascular necrosis, degenerative condylar remodeling, osteoarthritis, musculotendinous injuries, and atrophy of masticatory muscles. After imaging studies, seven patients underwent surgery, at which time imaging findings were confirmed; one patient underwent successful aspiration of a painful hemarthrosis. TMJ injuries may result in joint derangement, radiologically demonstrable joint degeneration, masticatory muscle dysfunction, pain, and progressive clinical disability.

Excitability of the central masticatory pathways in patients with painful temporomandibular disorders

Emerging evidence suggests an increased incidence of mechanical complications in natural teeth, particularly maxillary premolars, adjacent to dental implants. This study aimed to investigate and compare the maximum von Mises stress induced in a natural tooth adjacent to either a natural tooth or a dental implant under different occlusal loading and interproximal space conditions.Three-dimensional finite element models of maxillary first and second premolars were generated for both control (two natural teeth) and experimental (first premolar dental implant and natural second premolar) groups to analyze stress levels and distributions. Occlusal forces were applied to the second premolar, and the resulting maximum von Mises stress was compared between groups. The influence of dental implant presence, interproximal space, and occlusal load contact position and direction on the stress level and distribution in the loaded tooth was investigated.Compared with the control group, the experimental group exhibited higher stress levels in the natural second premolar under occlusal forces, although the stress distribution remained similar. The presence of interproximal spaces, either between natural teeth or between a tooth and an implant, exacerbated stress in the loaded teeth due to reduced proximal contact area and increased stress concentration. Additionally, the position and direction of occlusal force contact differentially affected the stress level, although not the stress distribution, within the experimental tooth group.Dental implants increase stress on adjacent natural teeth, particularly when interproximal space exists. Occlusal force direction and position influence stress in loaded natural teeth, whether adjacent to other natural teeth or implants. The results underscore the critical importance of comprehensive patient evaluation, meticulous treatment planning, and consistent maintenance in dental implant restorations to mitigate potential complications affecting adjacent natural teeth.

To compare the morphological characteristics of full crowns designed by an experienced dental technician and a data-driven artificial intelligence (AI) system, with particular attention to their similarity to natural teeth. Twelve digital casts, including mandibular right second premolars, were collected, three-dimensional (3D) printed, and prepared by an experienced dentist. For each case, two crowns were independently designed by an experienced dental technician (ET) and the AI system. Morphological characteristics, including buccal and lingual cusp angle, buccal-lingual diameter, mesial-distal diameter, functional cusp wear facets, 3D similarity, and occlusal contact point counts, were compared among natural teeth, ET crowns, and AI crowns. Functional cusp wear and occlusal contacts were evaluated qualitatively, based on morphological observation and visual analysis under virtual articulating paper conditions. Statistical analysis was performed using one-way analysis of variance (ANOVA) followed by least significant difference (LSD) post-hoc testing, with the significance level set at α = 0.05. Both AI crowns (56.2° ± 5.1°) and ET crowns (57.5° ± 6.3°) exhibited larger buccal cusp angles than natural teeth (45.7° ± 4.9°) (p < 0.05), while no significant differences were found in lingual cusp angles among the groups (p = 0.434, 0.607, 0.787). The buccal-lingual diameter of AI crowns closely matched natural teeth (p = 0.094), whereas ET crowns were significantly smaller than both AI crowns (p = 0.034) and natural teeth (p = 0.044). The mesial-distal diameter of AI crowns also showed no significant difference from natural teeth (p = 0.223), while ET crowns differed significantly from both groups (p = 0.047, 0.002). Although AI crowns exhibited slightly lower 3D discrepancy (0.43 ± 0.07) than ET crowns (0.48 ± 0.06), the difference was not statistically significant (p = 0.089). AI did not accurately reproduce functional cusp wear facets, whereas technician designs tended to overcompensate. Occlusal contact counts showed no significant differences among groups. AI systems can reproduce overall crown morphology to a degree comparable with experienced technicians but remain limited in replicating functional wear facets. AI offers a practical and efficient tool for crown design, with potential to improve consistency and reduce manual workload in prosthodontics. However, further refinement is required before these systems can fully replicate functional morphological details for widespread clinical application.

ObjectiveTo use a T-scan (Tekscan, Boston, USA) to evaluate the grinding effect of a three-dimensional (3D) printed occlusal splint and provide reference guidelines for adjusting occlusion and alleviating temporomandibular joint symptoms before orthodontic treatment.MethodsEighteen patients with temporomandibular disorder (TMD) were treated with 3D-printed stable occlusal plates for three months. The occlusal time (OT) of the dentition and the difference percentage of occlusal force between the left and right sides (Asymmetry index of occlusal force, AOF) were observed one week, one, two, and three months after T-scan-guided occlusal splint treatment. Before and after treatment, we investigated joint space, electromyography (EMG), the maxillofacial pain visual analog scale (VAS), and the Chinese version of the jaw function limitation scale (JFLS).ResultsSignificant reductions in OT and AOF were observed across four time points in TMD patients wearing T-scan-guided occlusal splints (P < 0.05). Furthermore, the bilateral masseter muscle (MM) and temporalis anterior (TA) asymmetry index were reduced at the mandibular postural and intercuspal positions. Cone beam computed tomography (CBCT) showed that the anterior space of the articular had decreased, the posterior space had increased, and the VAS and JFLS scores had decreased significantly (P < 0.05).ConclusionT-scan accurately located the abnormal occlusal contact point, guidance enhances occlusal equilibration and may improve TMJ function and symptoms in TMD patients.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12903-025-06622-x.

The clinician must frequently make treatment decisions with limited knowledge of the appropriateness and consequences of the different options. Patients have specific expectations: that the treatment they receive is the usual one, that they have been informed of the alternatives and the consequences, and most importantly that the treatment has a reasonable chance of success. In TMJ therapy, as with most treatments, the patient's improvement is closely connected to a proper diagnosis based on sound physiologic principles. This investigation will review four basic splint types and discuss their success in the resolution of various temporomandibular disorders. Since the position of the condyle-disc-fossa, the occlusal contact pattern and the masticatory muscle dynamics are interrelated, this study will focus on the physiologic changes splints may cause with modification of this tooth, joint and muscle relationship. Hopefully, selection of a specific splint design appropriate to the patient's disorder will be facilitated by better understanding of its physiologic and therapeutic effects.

To fabricate a prosthesis which is functionally harmonized with the stomatognathic system, the interocclusal relationship must be reproduced as accurately as possible. This study investigated the influence of the occlusal contacts upon tooth displacement and clarified the optimal occlusal contacts for the prosthesis. The displacement paths of six maxillary left first molars of six adults in good general health were measured in this study. We gave each test tooth eight patterns of artificial occlusal contacts by attaching platinum foil on the occlusal surface. Subjects were asked to perform clenching at the intercuspal position (= ICP) with medium occlusal forces, and 3-dimensional tooth displacement paths were measured by the Type M-3 tooth displacement transducer. The following conclusions were obtained. 1. Using the Student's t-test for statistical analysis, it was suggested that the difference of the buccolingual location of occlusal contacts influenced the direction of the tooth displacement. 2. The tooth which had occlusal contact in the buccal cusp displaced in the mesio-buccal direction, so this may create a wide dental arch and a slight discrepancy was generated at the distal interproximal contact area of the tooth. 3. It was shown that the tooth which had occlusal contact in the buccal cusp rotated in the buccoapical direction in reverse to the natural tooth.

Reliability, validity, and utility of various occlusal measurement methods and techniques

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