Search Results (83)

Background/Objectives: Diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide (TPO) is widely used in the dental industry as a photoinitiator for resin-based materials, while its use may be further limited given its toxicological risks. The aim of this study was, therefore, to analyze the residual TPO content of 3D-printed resin-based dental splint materials. Methods: Six resin-based splint materials were analyzed: LuxaPrint Ortho Plus (DMG), FREEPRINT splint 2.0 (Detax), optiprint splint (Dentona), KeySplint Soft (KeyPrint), FREEPRINT ortho (Detax), V-Print splint comfort (Voco). Grid-shaped specimens were fabricated using the recommended workflow of each manufacturer (n = 18). TPO extraction was conducted using a maximum of eight extraction cycles of 72 h at a temperature of 37 °C until no more TPO eluates were detected by high-performance liquid chromatography (HPLC). The margin of safety (MoS) was calculated as the ratio between the Derived No-Effect Level (DNEL) and the estimated exposure based on the amount of TPO extracted. Results: The total amount of extracted TPO was the lowest for LuxaPrint Ortho Plus (Mean ± SD; 44.0 ± 17.1 ng/mL), followed by optiprint splint (80.6 ± 21.1 ng/mL), FREEPRINT splint 2.0 (127.4 ± 25.3 ng/mL), FREEPRINT ortho (2813.2 ± 348.0 ng/mL), V-Print splint comfort (33,424.6 ± 8357.9 ng/mL) and KeySplint Soft (42,083.5 ± 3175.2 ng/mL). For all tested materials, the calculated MoS was above the critical value of 1, demonstrating toxicological safety in the cured, clinically relevant state. Conclusions: Large differences in the residual TPO content were observed between the materials. Although the TPO content in the uncured state may exceed toxicological safety limits, appropriate curing of the investigated materials resulted in a significant reduction in TPO elution and, thus, in products with a very low toxicological risk for the patient. Full article

Background: Temporomandibular joint disc displacement with reduction is one of the most common types of TMJ arthropathy. This single-blinded, randomized clinical study aimed to evaluate the effectiveness of three different therapeutic methods. Methods: Standard splints (Group 1), modified occlusal splint (Group 2), and conventional physical therapy with exercises (Group 3). A total of 48 patients were randomly assigned by a computer-generated allocation sequence to receive rehabilitation. The outcome was defined as improvements in pain and intermittent locking episodes. The follow-up visits were scheduled as one month and a long-term evaluation at one (T1), two (T2), three (T3), and four years (T4). Magnetic resonance images were also taken to evaluate each patient before treatment and at one year. Image analysis involved the evaluation of morphology and the function of intra-articular structures. Variables such as age, gender, and pre- vs. post-treatment values of VAS and TMJ locks between the three intervention categories were compared for statistical evaluations. p values ≤ 0.05 were taken as being significant. Results: A total of 16 subjects were allocated to each group. At T1, a decrease in pain and TMJ locking episodes was observed, which was maintained throughout the course of the study for four years of follow-ups, with no statistically significant differences. However, there was a tendency for better outcomes in favor of Group 2, with less clicking of the TMJ at opening. Conclusions: The modified mandibular splint seems to be successful as an effective alternative for the management of temporomandibular joint disc displacement with reductions in intermittent locking. Full article

Background: Manual therapy (MT) and occlusal splint therapy (OST) are the most conservative therapies applied on patients with temporomandibular disorders (TMDs). The aim was to compare the efficacy of MT vs. OST in improving pain, maximal mouth opening (MMO), disability, and health related-quality of life (hr-QoL) in these patients. Methods: According to PRISMA guidelines, a meta-analysis (CRD42022343915) was conducted including randomized controlled trials comparing the effectiveness of MT vs. OST in TMD patients, after searching in PubMed, PEDro, SCOPUS, and WOS up to March 2024. Methodological quality and risk of bias were assessed using the PEDro Scale. Cohen’s standardized mean difference (SMD) and its 95% confidence interval (95% CI) were the pooled effect measures calculated. Results: Nine studies, providing data from 426 patients, were included. Meta-analyses revealed that MT is more effective than OST in reducing disability (SMD = −0.81; 95% CI −1.1 to −0.54) and increasing MMO (SMD = 0.52; 95% CI 0.27 to 0.76) without differences for improving pain intensity and hr-QoL. Subgroup analyses revealed the major efficacy of OST in reducing pain in myogenic patients (SMD = 0.65; 95% CI 0.02 to 1.28). Conclusions: With caution, due to the low number of studies included, MT may be more effective than OST for improving disability and MMO in patients with TMDs. Full article

Background: Sleep apnea and nocturnal bruxism belong to sleep disorders that can affect the quality of life. The aim of this study was to investigate the effects on patients with moderate sleep apnea and nocturnal bruxism of Botox injection as monotherapy or associated with wearing thermoformed occlusal splints and to determine the patients’ satisfaction degree after the applied treatments. Methods: The selected patients for study were divided into two groups: in the first group, the patients (n = 18) treatment consisted of injecting Botox (Allergan) into the masseter muscle as monotherapy; in the second group, the patients (n = 18) benefited from associated therapy, Botox injections in masseter muscle, and the wear of thermoformed occlusal splints. At baseline, at three weeks, at three months, and six months after the effectuation of therapies, the monitoring sessions were realized. Results: The associated therapy presented better results in decreasing the studied symptoms than the monotherapy. Both therapies improved patient satisfaction. Conclusions: The applied therapies for treating the specific symptomatology in moderate sleep apnea and sleep bruxism were efficacious. Patient satisfaction was very good in both groups after the applied treatments, but the associated therapy presented better results than monotherapy. Full article

Introduction: Digital workflow and intraoral scanners (IOSs) are used to clinically obtain data for a wide range of applications in restorative dentistry. The study aimed to compare two different IOSs with inexperienced users in the digital workflow of oral split manufacturing. Material and Methods: Anonymous stone models of upper and lower dentate patients were used. Both models were scanned with a desktop 3D scanner 3Shape D2000 to obtain the reference models (STL_R). Ten inexperienced operators scanned each model three times with each IOS system (3Shape TRIOS 3 and Carestream CS 3800). Finally, 20 intraoral scanners were randomly chosen from the obtained dataset (10 per IOS system) to design and manufacture 20 nightguards. All the nightguards were scanned. Trueness and precision were calculated and compared between the two IOS systems. Results: All the mean errors both for trueness and precision were below 40 µm, more than acceptable for the design and manufacturing of intraoral devices such as nightguards. All the mean errors (except one) for trueness between the inner part of the nightguards and the upper control model were below 100 µm, less than a printed layer height. For inexperienced operators, both IOSs are suitable for a digital workflow of manufacturing occlusal splints. Full article

Background: Temporomandibular disorders (TMD) may be associated with degenerative disease of temporomandibular joint (TMJ), such as condyle erosion and subchondral cysts. Occlusal splint and cranio-mandibular manual therapy, or combined therapy, is recommended as a conservative treatment to alleviate pain-related signs and symptoms in TMD. This study aimed to assess osseous condylar changes and skeletal changes following occlusal splint and cranio-mandibular manual therapy in TMD using cone beam computed tomography (CBCT). Methods: A retrospective cohort study included 24 patients diagnosed with TMD. Combined therapy was performed until pain-related signs and symptoms disappeared. CBCT scans were performed before and after therapy. Osseous structure of condyles and their subsequent modifications were analyzed on CBCT images: flattening, erosion, and subchondral cyst. Sella-Nasion-A point (SNA), Sella-Nasion-B point (SNB), A point-Nasion-B point (ANB), Sella-Articulare-Gonion (Condylar angle), and anterior and posterior facial height (AFH, PFH) were measured on CBCT-generated lateral cephalograms. A paired t-test, Wilcoxon rank-sum test, McNemar test, and Stuart–Maxwell test were used for the statistical analyses. Results: The treatment period with combined therapy was 7.42 ± 3.27 months, and 21 out of 33 TMJ presenting degenerative disease (63.6%) had significant complete remodeling (p < 0.05). Following therapy, SNB significantly decreased from 75.61 ±3.47° to 74.82 ± 3.41° (p = 0.02), ANB significantly increased from 4.05° (3.35–4.9°) to 4.8° (3.3–6.12°) (p < 0.001), AFH significantly increased from 112.85 mm (109.28–118.72) to 115.3 mm (112.58–118.88) (p < 0.001), PFH/AFH significantly decreased from 64.17 (61.39–66.1) to 63 (59.68–64.51) (p = 0.012), and condylar angle significantly increased from 140.84 ± 8.18° to 144.42 ± 8.87° (p = 0.007). Conclusion: Combined therapy promoted significant condylar remodeling in TMJ degenerative disease, along with skeletal changes (mandibular retrusion and increase in facial height). Therapeutic strategies should consider condylar remodeling in TMD. Skeletal and dental parameters should be evaluated prior to occlusal splint therapy. Full article

The effects of occlusal splints on sport performance have already been studied, although their biomechanical impacts are often overlooked. We investigated the kinematical changes during running until exhaustion at severe intensity while wearing a mandibular advancement occlusal splint. Twelve trained runners completed (i) an incremental protocol on a track to determine their velocity corresponding to maximal oxygen uptake and (ii) two trials of square wave transition exercises at their velocity corresponding to maximal oxygen until exhaustion, wearing two occlusal splints (without and with mandibular advancement). Running kinematics were compared within laps performed during the square wave transition exercises and between splint conditions. The mandibular advancement occlusal splint increased the running distance covered (~1663 ± 402 vs. 1540 ± 397 m, p = 0.03), along with a noticeable lap effect in decreasing stride frequency (p = 0.04) and increasing stride length (p = 0.03) and duty factor (p < 0.001). No spatiotemporal differences were observed between splints, except for improved balance foot contact times in the mandibular advancement condition. An increased knee flexion angle at initial contact (p = 0.017) was noted along laps in the non-advancement condition, despite the fact that no differences between splints were found. Running patterns mainly shifted within laps rather than between conditions, indicating that a mandibular advancement occlusal splint had a trivial kinematical effect. Full article

Additive manufacturing resins used in dental prosthetics may retain uncured monomers post-polymerization, posing potential long-term patient exposure risks. Understanding the biological safety of these materials is crucial, particularly for 3D-printed acrylic-based prosthodontic devices such as occlusal nightguards, complete and partial dentures, and temporary fixed prostheses. This paper reviews the literature evaluating the cytotoxicity of such materials. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines, we conducted a scoping review using the MESH keywords related to population (P), intervention (I), comparison (C), and outcome (O) across databases, including OVID Medline, EMBASE, and SCOPUS. Our search, limited to peer-reviewed English language articles from 2015 to 2023, resulted in 22 papers. These studies, utilizing digital light processing (DLP) or stereolithography (SLA) printing methods, varied in examining different 3D-printed materials, as well as washing and post-curing protocols. The primary experimental cells used were human gingival fibroblasts (HGF) and mouse fibroblasts (L929). There are no statistical differences in biocompatibility regarding different commercially available resins, washing solutions, or methods. Improvements in cell viability were related to an increase in washing time, as well as post-curing time. After the polishing procedure, 3D resin-based printed occlusal devices perform similarly to milled and conventionally processed ones. Our findings underline the importance of appropriate washing and post-curing protocols in minimizing the cytotoxic risks associated with these 3D-printed resin-based devices. Full article

We investigated the acute biophysical responses of changing the mandibular position during a rowing incremental protocol. A World-class 37-year-old male rower performed two 7 × 3 min ergometer rowing trials, once with no intraoral splint (control) and the other with a mandibular forward repositioning splint (splint condition). Ventilatory, kinematics and body electromyography were evaluated and compared between trials (paired samples t-test, p ≤ 0.05). Under the splint condition, oxygen uptake was lower, particularly at higher exercise intensities (67.3 ± 2.3 vs. 70.9 ± 1.5 mL·kg⁻¹·min⁻¹), and ventilation increased during specific rowing protocol steps (1st–4th and 6th). Wearing the splint condition led to changes in rowing technique, including a slower rowing frequency ([18–30] vs. [19–32] cycles·min⁻¹) and a longer propulsive movement ([1.58–1.52] vs. [1.56–1.50] m) than the control condition. The splint condition also had a faster propulsive phase and a prolonged recovery period than the control condition. The splint reduced peak and mean upper body muscle activation, contrasting with an increase in lower body muscle activity, and generated an energetic benefit by reducing exercise cost and increasing rowing economy compared to the control condition. Changing the mandibular position benefited a World-class rower, supporting the potential of wearing an intraoral splint in high-level sports, particularly in rowing. Full article

We carried out a comparison of the neuromuscular and clinical effects produced by electrostimulation therapies, as an adjuvant to the use of occlusal splints (removable muscle relaxation apparatus) in patients with temporomandibular disorders In this simple randomized clinical trial, 91 patients were randomly divided into three groups. Group A (GA) received transcutaneous electrostimulation therapy and an occlusal splint, Group B (GB) received percutaneous electrostimulation therapy and an occlusal splint, and Group C (GC) received an occlusal splint. The neuromuscular activity, as well as the signs and symptoms of each patient, were evaluated every week throughout the treatment (T0 = baseline; T1 = 7 days; T2 = 14 days; T3 = 21 days; T4 = 28 days; and T5 = 35 days). Pain was measured with a visual analog scale, and neuromuscular electrical activity was determined by the root mean square of the masseter muscles through the use of a UNAM-CINVESTAV 1.2 electromyograph. Comparisons were made using ANOVA for repeated measures (p-value = 0.05). The comparison between the groups determined that muscle fatigue (p-value = 0.001), joint pain (p-value = 0.009), and muscle pain (p-value = 0.003) decreased to a greater extent, and in the short term for the group treated with transcutaneous electrostimulation therapy as an adjuvant to the use of the occlusal splint. The comparison between the groups determined that muscle fatigue (p-value = 0.001), joint pain (p-value = 0.009), and muscle pain (p-value = 0.003) decreased to a greater extent and in a shorter term in the GA (calculation therapy, transcutaneous electrostimulation) and GB (occlusal splint). Transcutaneous electrostimulation is a feasible and faster alternative that was accepted by most of the patients for treating temporomandibular disorders. Full article

The objective of this study was to compile the currently available evidence regarding the functional and morphologic outcomes of functional orthodontic therapy for mandibular condyle fracture. We performed searches in PubMed and Google Scholar as well as manually (IOK issues 2008–2019) using the keywords “trauma”, “TMJ”, “activator”, “condylar fracture”, “fracture”, “mandibular condylar fracture”, “occlusal splint” and “functional appliance”. Screening and analysis of study eligibility were performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The search strategy identified 198 studies published between 1971 and 2018, with 93 studies remaining after removing duplicate hits. Of the 93 studies, 19 were included in this study, considering the inclusion criteria. There were 12 follow-up, 4 prospective, and 3 purely retrospective studies. Some of the studies showed good functional results of mandibular condyle fracture treatment, in addition to subjective patient satisfaction. The incisal edge difference could be increased to physiological ranges of >35 mm by means of activator therapy. Partial mandibular deviations to the fractured side remained post-therapy, especially after unilateral fractures. Fractures without significant dislocation and luxation showed radiographic changes in shape, described as hypoplastic and ellipsoid, in addition to good morphologic results. One study found that collum length shortened twofold after a luxated fracture compared with fractures without significant dislocation, despite activator therapy. Straightening of the fragment occurred only in the low-dislocated fragments. Overall, children showed a higher remodeling potential than adult patients. Several studies observed an improved clinical outcome for functional therapy after mandibular condyle fracture. The outcome is essentially determined by fracture type, fracture height, and age. Further studies, especially prospective studies, are necessary to improve the evidence of functional orthodontic therapy for mandibular condyle fractures. Full article

Background: Temporomandibular disorders (TMDs) frequently cause orofacial pain and dysfunction, with treatment options spanning from conservative therapies to invasive surgical procedures. The aim of this systematic review was to analyze and compare the efficacy and safety profiles of conservative, minimally invasive interventions and surgical procedures in patients diagnosed with TMDs and disc displacement. Methods: Following PRISMA recommendations, PubMed, Scopus, and Web of Science databases were searched for randomized clinical trials (RCT). Data were synthesized in a table and evaluated through the Cochrane risk of bias 2 (RoB 2) tool. Results: Thirty-eight RCTs, most with moderate RoB, were selected. Conservative approaches, including physical therapy and occlusal devices, led to an improvement in symptoms and function. Pharmacological treatments demonstrated effectiveness in reducing pain and improving function; however, they can have undesirable side effects. Minimally invasive and invasive treatments also demonstrated efficacy, although most trials did not show their superiority to conservative treatments. Conclusion: The primary approach to TMDs should be a conservative, multimodal treatment plan tailored to patient complaints and characteristics. Treatment goals should focus on symptom control and functional recovery. Surgical treatment should be reserved for cases with a precise diagnosis and a clear etiology. Full article

Background: Tooth infraocclusion is a process in which a completely or partially erupted tooth gradually moves away from the occlusal plane. Submerged teeth can lead to serious complications. Treating teeth with infraocclusion is very challenging. One of the procedures allowing for the replacement of a missing tooth is autotransplantation. The aim of this paper is to review the literature on teeth autotransplantation, supported by a case report involving the autotransplantation of a third mandibular molar into the site of an extracted infraoccluded first mandibular molar, as well as the utilization of advanced platelet-rich fibrin (A-PRF) alongside autogenous dentin grafts for bone tissue regeneration. Methods: A severely infraoccluded first permanent right mandibular molar was extracted and then ground to obtain the dentin graft. A-PRF clots (collected from the patient’s peripheral blood) were added to the autogenous dentin graft, to create the A-PRF membrane. An atraumatic extraction of the lower left third molar was performed and then it was transplanted into the socket of tooth no. 46. Immediately after transplantation, tooth no. 38 was stabilized with orthodontic bracket splints for 3 months. The patient attended regular follow-up visits within 12 months. Results: After one year, the patient did not report any pain. In the clinical examination, the tooth and surrounding tissues did not show any signs of infection. However, radiographically, cervical inflammatory resorption, unchanged pulp canal dimensions, absent root growth, periapical radiolucency, and lack of apical and marginal healing were observed. Reconstruction of the bone defect was obtained and the alveolar ridge of the mandible was preserved. Due to poor stability of the tooth and severe resorption, the tooth needed to be extracted. Conclusions: This study is designed to critically evaluate the efficacy of autotransplantation, the application of growth factors, and the integration of autogenous dentin grafts in remedying dental deficiencies resulting from reinclusion. We aim to point out the possible causes of treatment failure. Full article

Background and objectives: This study analyzed and compared the distribution patterns of occlusal forces using T-Scan III before and after the hydrostatic temporary oral splint (Aqualizer Ultra) therapy in healthy subjects and subjects with temporomandibular disorders (TMDs). Materials and Methods: Fifty-one subjects were divided into groups based on anamnesis and responses to the Fonseca questionnaire. The first group, non-TMDs group (n = 19), and the second group, TMDs group (n = 32), had mild-to-severe TMDs, as identified by the Fonseca questionnaire. The non-TMDs group had an average age of 25.4 years (SD = 4.8, range 20–38) with 15 females (78.95%) and 4 males (21.05%). The TMDs group had an average age of 27.4 years (SD = 7.0, range 22–53) with 25 females (78.125%) and 7 males (21.875%). T-Scan III device was used for occlusal analysis before and after hydrostatic splint usage. Results: Significant differences were observed in the TMDs group for anterior and posterior right percentages of forces before and after hydrostatic splint usage. The analysis of force distribution per sector before and after hydrostatic splint therapy showed no significant differences in the non-TMDs group. Analysis of force distributions in the entire study population before and after hydrostatic splint therapy showed significant differences in the anterior and posterior right regions. Occlusal force increased by 32–56% in the front region and decreased in the posterior area after hydrostatic splint usage. Conclusions: Hydrostatic splint therapy is recommended as a part of full-mouth rehabilitation treatment for all patients regardless of the severity of TMDs. Full article

The aim of this study is to investigate the influence of printing material, build angle, and artificial aging on the accuracy of SLA- and DLP-printed occlusal devices in comparison to each other and to subtractively manufactured devices. A total of 192 occlusal devices were manufactured by one SLA-printing and two DLP-printing methods in 5 different build angles as well as milling. The specimens were scanned and superimposed to their initial CAD data and each other to obtain trueness and precision data values. A second series of scans were performed after the specimens underwent an artificial aging simulation by thermocycling. Again, trueness and precision were investigated, and pre- and post-aging values were compared. A statistically significant influence was found for all main effects: manufacturing method, build angle, and thermocycling, confirmed by two-way ANOVA. Regarding trueness, overall tendency indicated that subtractively manufactured splints were more accurate than the 3D-printed, with mean deviation values around ±0.15 mm, followed by the DLP1 group, with ±0.25 mm at 0 degree build angle. Within the additive manufacturing methods, DLP splints had significantly higher trueness for all build angles compared to SLA, which had the highest mean deviation values, with ±0.32 mm being the truest to the original CAD file. Regarding precision, subtractive manufacturing showed better accuracy than additive manufacturing. The artificial aging demonstrated a significant influence on the dimensional accuracy of only SLA-printed splints. Full article