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The Journal of Advanced Prosthodontics Oct 2023This study aimed to assess and compare the color stability, flexural strength (FS), and surface roughness of occlusal splints fabricated from heat-cured acrylic resin,...
PURPOSE
This study aimed to assess and compare the color stability, flexural strength (FS), and surface roughness of occlusal splints fabricated from heat-cured acrylic resin, milled polymethyl methacrylate (PMMA)-based resin, and 3D-printed (PMMA) based-resin.
MATERIALS AND METHODS
Samples of each type of resin were obtained, and baseline measurements of color and surface roughness were recorded. The specimens were divided into three groups (n = 10) and subjected to distinct aging protocols: thermomechanical cycling (TMC), simulated brushing (SB), and control (without aging). Final assessments of color and surface roughness and three-point bending test (ODM100; Odeme) were conducted, and data were statistically analyzed (2-way ANOVA, Tukey, <.05).
RESULTS
Across all resin types, the most significant increase in surface roughness (Ra) was observed after TMC ( < .05), with the 3D-printed resin exhibiting the lowest Ra ( < .05). After brushing, milled resin displayed the highest Ra ( < .05) and greater color alteration (ΔE) compared to 3D-printed resin. The most substantial ΔE was recorded after brushing for all resins, except for heat-cured resin subjected to TMC. Regardless of aging, milled resin exhibited the highest FS ( < .05), except when compared to 3D-printed resin subjected to TMC. Heat-cured resin exposed to TMC demonstrated the lowest FS, different ( < .05) from the control. Under control conditions, milled resin exhibited the highest FS, different ( < .05) from the brushed group. 3D-printed resin subjected to TMC displayed the highest FS ( < .05).
CONCLUSION
Among the tested resins, 3D-printed resin demonstrated superior longevity, characterized by minimal surface roughness and color alterations. Aging had a negligible impact on its mechanical properties.
PubMed: 37936836
DOI: 10.4047/jap.2023.15.5.227 -
Journal of Personalized Medicine Oct 2023We aimed to investigate whether the collaboration of shear wave elastosonography (SWE) and B-mode ultrasonography (US) could be offered as diagnostic tools to assess the...
We aimed to investigate whether the collaboration of shear wave elastosonography (SWE) and B-mode ultrasonography (US) could be offered as diagnostic tools to assess the presence, severity, and progress of bruxism, as well as a biomarker for the effectiveness of treatment in daily clinical practice. The study was designed as a quantitative evaluation of the masseter muscles (MMs) of the clinically diagnosed bruxism patients suffering from myofascial pain and MMs of the healthy individuals. Clinical examinations were made according to the diagnostic criteria for temporomandibular disorders (DC/TMD), and pain was assessed using a visual analog scale (VAS). Painful MMs with VAS scores ≥ 4 were assigned to Group A, and healthy MMs were assigned to Group B. Also, the MMs of the painful bruxers were analyzed based on wearing occlusal splints. Group A was divided into two subgroups as splint users (Group AI) and non-users (Group AII). All the participants were scanned with dynamic US and SWE to quantify the size and stiffness of the MMs. Measurements of each muscle pair while the jaw is in a resting position (relaxation) and clenching position (contraction) were recorded. The significant differences in stiffness and thickness became visible in the relaxation state. Bruxism patients with myofascial pain had significantly harder and thinner MMs than healthy individuals. During the relaxation, the mean thickness and elasticity values were 9.17 ± 0.40 mm and 39.13 ± 4.52 kPa for Group A and 10.38 ± 0.27 and 27.73 ± 1.92 for Group B, respectively. Also, stiffer MMs were measured in Group AII (38.16 ± 3.61 kPa) than in Group AI (26.91 ± 2.13 kPa). In conclusion, the combination of SWE and US using a dynamic examination technique has the potential to be a valuable tool for the management of bruxism patients suffering from myofascial pain.
PubMed: 37888078
DOI: 10.3390/jpm13101467 -
The Angle Orthodontist Mar 2024To evaluate the influence of facial biotype in the therapeutic effect of mandibular advancement devices (MADs) according to polysomnographic records in patients...
Predictive factors of therapeutic response according to craniofacial skeletal biotype in patients with sleep apnea syndrome using mandibular advancement devices: a pilot study.
OBJECTIVES
To evaluate the influence of facial biotype in the therapeutic effect of mandibular advancement devices (MADs) according to polysomnographic records in patients diagnosed with sleep apnea-hypopnea syndrome (SAHS).
MATERIALS AND METHODS
A total of 46 patients were recruited. Patients were classified according to facial biotype (mesofacial, brachyfacial, or dolichofacial). The quantitative variables were described as the arithmetic mean and standard deviation or the median and interquartile range. Hypothesis tests used were Pearson's chi-square, paired-sample Student's t- test, the Wilcoxon test, one-way analysis of variance, Kruskal-Wallis test, and Mann-Whitney U-test. P < .05 was considered statistically significant.
RESULTS
A total of 46 patients were categorized into three facial biotype subgroups with no significant differences among them in age, body mass index, neck circumference, and sex. The respiratory disturbance index (RDI) results were as follows: brachyfacial patients had a reduction to 15 events/h (P < .001), the mesofacial patients had a reduction to 14 events/h (P < .001), and the dolichofacial patients did not show a significant reduction. The oxygen desaturation index (ODI) results were as follows: brachyfacial patients had a reduction in ODI episodes to 45 episodes/h (P = .001), mesofacial patients had a reduction to 18 episodes/h (P = .001). In the brachyfacial group, the number of awakenings with MAD therapy was reduced to 23 events/h (P = .003), while, in the mesofacial group, it was reduced to 37 episodes/h (P = .012).
CONCLUSIONS
The facial biotype influences the effectiveness of MAD therapy and is considered a good predictive factor.
Topics: Humans; Pilot Projects; Mandibular Advancement; Sleep Apnea Syndromes; Sleep Apnea, Obstructive; Face; Treatment Outcome
PubMed: 37788163
DOI: 10.2319/092822-670.1 -
Sleep & Breathing = Schlaf & Atmung Mar 2024This study aimed to evaluate the effect of mandibular advancement splint (MAS) therapy on cardiac autonomic function in patients with obstructive sleep apnoea (OSA)...
PURPOSE
This study aimed to evaluate the effect of mandibular advancement splint (MAS) therapy on cardiac autonomic function in patients with obstructive sleep apnoea (OSA) using heart rate variability (HRV) analysis.
METHODS
Electrocardiograms (ECG) derived from polysomnograms (PSG) of three prospective studies were used to study HRV of patients with OSA before and after MAS treatment. HRV parameters were averaged across the entire ECG signal during N2 sleep using 2-min epochs shifted by 30 s. Paired t-tests were used to compare PSG and HRV measures before and after treatment, and the percent change in HRV measures was regressed on the percent change in apnoea-hypopnea index (AHI).
RESULTS
In 101 patients with OSA, 72% were Caucasian, 54% men, the mean age was 56 ± 11 years, BMI 29.8 ± 5.3 kg/m, and treatment duration was 4.0 ± 3.2 months. After MAS therapy, there was a significant reduction in OSA severity (AHI, - 18 ± 16 events per hour, p < 0.001) and trends towards increased low-frequency to high-frequency ratio, low-frequency power, and reduced high-frequency power (LF:HF, - 0.4 ± 1.5, p = 0.01; LF, - 3 ± 16 nu, p = 0.02, HF, 3.5 ± 13.7 nu, p = 0.01). Change in NN intervals correlated with the change in AHI (β(SE) = - 2.21 (0.01), t = - 2.85, p = 0.005). No significant changes were observed in the time-domain HRV markers with MAS treatment.
CONCLUSION
The study findings suggest that successful MAS treatment correlates with changes in HRV, specifically the lengthening of NN intervals, a marker for improved cardiac autonomic adaptability.
Topics: Male; Humans; Middle Aged; Aged; Female; Occlusal Splints; Prospective Studies; Sleep Apnea, Obstructive; Heart; Heart Rate; Mandibular Advancement
PubMed: 37770793
DOI: 10.1007/s11325-023-02924-y -
Materials (Basel, Switzerland) Sep 2023The development of digital technologies has allowed for the fabrication of new materials; however, it makes it difficult to choose the best methods to obtain occlusal...
UNLABELLED
The development of digital technologies has allowed for the fabrication of new materials; however, it makes it difficult to choose the best methods to obtain occlusal splints with optimal properties, so it is essential to evaluate the effectiveness of these materials. The aim of the study is to compare the fracture resistance of occlusal splints made of different materials after thermo-mechanical aging.
METHODS
A total of 32 samples were made from 4 materials (two 3D printed polymeric materials, a PMMA disc for CAD/CAM, and a conventional heat-cured acrylic resin); subsequently, the fracture test was performed using the load compression mode applied occlusally on the splint surface.
STATISTICAL ANALYSIS
Four statistical tests were used (Shapiro-Wilk, Levene's test, ANOVA, and Tukey's HSD test).
RESULTS
The following study showed that there are differences in fracture strength among the four materials investigated, where the highest strength was observed in the milled splint, with a mean of 3051.2 N (newton) compared to the strength of the flexible splint with 1943.4 N, the printed splint with 1489.9 N, and the conventional acrylic splint with 1303.9 N.
CONCLUSIONS
The milled splints were the most resistant to fracture. Of the printed splints, the splint made with flexural rigid resin withstood the applied forces in acceptable ranges, so its clinical indication may be viable. Although the results of this research indicated differences in the mechanical properties between the CAD/CAM and conventional fabrication methods, the selection may also be influenced by processing time and cost, since with a CAD/CAM system there is a significant reduction in the production time of the splint material.
PubMed: 37763547
DOI: 10.3390/ma16186269 -
Bioengineering (Basel, Switzerland) Aug 2023(1) Background: Mandibular fractures are very common. Common indications of closed treatment for mandibular fractures are non-displaced or minimally displaced simple...
(1) Background: Mandibular fractures are very common. Common indications of closed treatment for mandibular fractures are non-displaced or minimally displaced simple fractures in adult compliant patients with good dentition, the absence of occlusal disruption, and fractures in growing children. In closed treatment, the mandible is maintained in centric occlusion with a maxillomandibular fixation (MMF) with orthodontic elastics. Many methods of MMF have been described, often using orthodontic appliances. In recent years, CAD-CAM technology has improved many procedures used in maxillofacial surgery and orthodontics. The device we present is manufactured following a digital workflow, and was designed specifically for MMF. (2) Materials: Two patients with mandibular fractures were treated with an MMF method whose procedure comprised scanning of the dental arches, followed by construction of thermoformed splints on which buttons for the elastics and retention holes are made. The splints were fixed on the dental arches with composite resin at the level of the holes, and were kept in place for the period of healing of the fracture, with the intermaxillary elastics hooked to the buttons. (3) Results: The application time of the splints was very quick. The splints remained stable for the necessary time, without causing particular discomfort to the patients. (4) Conclusions: From our experience, this technique has proved to be reliable and reproducible and could represent a valid tool in the closed treatment of mandibular fractures.
PubMed: 37760125
DOI: 10.3390/bioengineering10091023 -
BMC Oral Health Sep 2023Temporomandibular joint (TMJ) disc repositioning through open suturing (OSu) is a new disc repositioning method. Its result for adolescents with condylar resorption and... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Temporomandibular joint (TMJ) disc repositioning through open suturing (OSu) is a new disc repositioning method. Its result for adolescents with condylar resorption and dentofacial deformities combined with and without postoperative occlusal splints (POS) has not been well studied.
OBJECTIVE
This study was to evaluate and compare the effects of OSu with and without POS in the treatment of TMJ anterior disc displacement without reduction (ADDwoR) in adolescent skeletal Class II malocclusion.
METHODS
A total of 60 adolescents with bilateral ADDwoR were enrolled in this study. They were randomly allocated into two groups: OSu with and without POS. Magnetic resonance imaging (MRI) and lateral cephalometric radiographs were used to measure changes in condylar height and the degree of skeletal Class II malocclusion from before operation and at 12 months postoperatively. Changes in these indicators were compared within and between the two groups.
RESULTS
After OSu, both groups exhibited significant improvements in condylar height and occlusion at the end of 12 months follow-up (P < 0.05). The group of OSu with POS had significantly more new bone formation (2.83 ± 0.75 mm vs. 1.42 ± 0.81 mm, P < 0.001) and improvement in dentofacial deformity than the group of OSu only (P < 0.05). The new bone height was significantly correlated with POS (P < 0.001), the changes of SNB (P = 0.018), overjet (P = 0.012), and Wits appraisal (P < 0.001).
CONCLUSION
These findings indicated that OSu can effectively stimulate condylar regeneration and improve skeletal Class II malocclusion in adolescents with bilateral ADDwoR. The results are better when combined with POS.
TRIAL REGISTRATION
This trial was prospectively registered on the chictr.org.cn registry with ID: ChiCTR1900021821 on 11/03/2019.
Topics: Adolescent; Humans; Dental Occlusion; Joint Dislocations; Magnetic Resonance Imaging; Malocclusion, Angle Class II; Occlusal Splints; Temporomandibular Joint; Temporomandibular Joint Disc; Temporomandibular Joint Disorders
PubMed: 37759222
DOI: 10.1186/s12903-023-03402-3 -
JPMA. the Journal of the Pakistan... Aug 2023This case report demonstrates the full mouth prosthetic rehabilitation of a patient with generalised compensated tooth wear and oral sub-mucous fibrosis (OSMF). A 50-...
This case report demonstrates the full mouth prosthetic rehabilitation of a patient with generalised compensated tooth wear and oral sub-mucous fibrosis (OSMF). A 50- year-old female with advanced tooth wear and concomitant OSMF presented to the clinic. She was managed in a sequential manner using an occlusal splint, extractions of hopeless teeth, root canal treatment of strategically important teeth, surgical crown lengthening of abutment teeth, and dental implants to replace missing dentition, followed by crown and bridgework to rehabilitate the dentition. All procedures were done on the principles of re-organised occlusal intervention. The outcome was a functional dentition with an aesthetic smile and a satisfied patient. The regaining of mouth opening among OSMF subjects is a challenge. The usual management is prescribing muscle stretching exercises, drugs, or surgery. In the present case, we managed to achieve significant improvement in mouth opening with occlusal splints. The use of such occlusal orthotics has never been reported.
Topics: Female; Humans; Middle Aged; Tooth Wear; Mouth; Ambulatory Care Facilities; Anodontia; Esthetics
PubMed: 37697769
DOI: 10.47391/JPMA.6509 -
Journal of Oral Science Oct 2023Scientific evidence pertaining to the evaluation of trueness of occlusal splints fabricated using different three-dimensional (3D) printers and build orientations...
PURPOSE
Scientific evidence pertaining to the evaluation of trueness of occlusal splints fabricated using different three-dimensional (3D) printers and build orientations compared to subtractive technologies is lacking.
METHODS
Overall, one hundred and ten occlusal splints were manufactured using two different 3D printers and a dental mill. Five groups of ten were fabricated using the 3D printers at different build orientations (0, 30, 45, 60, and 90 degrees). In addition, a comparison group of ten occlusal splints was subtractively manufactured using a five-axis dental mill. All occlusal splints were scanned and exported as a standard tessellation language file. Analysis was conducted with metrology software with root mean square estimate average positive deviation and average negative deviation used as the measured outcome.
RESULTS
The 0 degree printing orientation was the most accurate for printer one with the root mean square value of 0.05 ± 0.01 mm, and 60 degree printing orientation was most accurate for printer two with the RMS value of 0.11 ± 0.01 mm. Subtractively manufactured occlusal splint had significantly higher trueness with the lowest RMS value of 0.03 ± 0.05 mm.
CONCLUSION
Build orientations influence the trueness of additively manufactured occlusal splints while occlusal splints produced by subtractive manufacturing were statistically significantly more accurate.
Topics: Occlusal Splints; Computer-Aided Design; Printing, Three-Dimensional; Software
PubMed: 37690838
DOI: 10.2334/josnusd.23-0115 -
Dental Materials : Official Publication... Oct 2023To evaluate and compare the mechanical properties, water sorption, water solubility, and degree of double bond conversion of three different commercially available...
OBJECTIVE
To evaluate and compare the mechanical properties, water sorption, water solubility, and degree of double bond conversion of three different commercially available three-dimensional (3D) printing resins used for the fabrication of flexible occlusal splints.
METHODS
A digital printer was used to generate specimens from the evaluated splint materials (KeySplint Soft, IMPRIMO LC Splint flex, and V-Print splint comfort). The specimens were equally divided and tested either dry or after water storage at 37 °C for 30 days. A three-point bending test was used to assess flexural strength, elastic modulus, and fracture toughness. A two-body wear test was performed using a dual-axis chewing simulator. Water sorption and water solubility were measured after 30 days. The degree of double bond conversion was determined by FTIR-spectrometry. All data for the evaluated properties were collected and statistically analyzed.
RESULTS
Both material and storage conditions had a significant effect on the flexural strength (P < 0.001), elastic modulus (P < 0.001), fracture toughness (P < 0.001), and wear (P < 0.001). The highest water sorption was noticed with IMPRIMO LC Splint flex (1.9 ± 0.0 %), while V-Print splint comfort displayed the lowest water solubility (0.2 ± 0.0 %). For the degree of conversion, it was statistically non-significant among the different materials (P = 0.087).
SIGNIFICANCE
Different flexible 3D-printed splints available in the market displayed variations in the evaluated properties and clinicians should consider these differences when choosing occlusal device materials. Among the tested flexible splint materials, KeySplint Soft had the greatest flexural strength, elastic modulus, fracture toughness, wear resistance, and degree of conversion. It also showed the lowest water sorption.
Topics: Occlusal Splints; Research Design; Elastic Modulus; Printing, Three-Dimensional; Water
PubMed: 37666693
DOI: 10.1016/j.dental.2023.08.178