The prognosis of myofascial pain syndrome (MPS) during a fixed orthodontic treatment

Among treatments in the literature for myofascial pain syndrome (MPS), the most reliable therapies in dentistry are spray and stretch, and, although less frequently used, anesthetic injection. Adult MPS subjects are often treated using fixed orthodontic therapy for resolution of malocclusion. There is no clarity in the literature on the prognosis of MPS during orthodontic therapy. The purpose of this study was to analyze the prognosis of MPS during orthodontic treatment of subjects with malocclusion, initially diagnosed as having MPS. The analysis covered the medical records of 91 young adult Caucasians scheduled for orthodontic treatment for various malocclusions. Thirty-seven of the patients were initially diagnosed as also having MPS (T0). Thirty patients began the orthodontic treatment and were recalled for a re-evaluation of MPS after dental alignment and dental class correction was achieved (T1). A wait-and-see strategy was applied in seven subjects who were included as the control subjects. They received no treatment for MPS. At T1, a statistically significant decrease was observed in the study group in the presence of any clicking or creaking noises from the jaw joint, a significant jaw joint and jaw muscle pain reduction, and a quality of life improvement. Among patients who were depressed at the beginning of treatment, the majority felt better at the follow-up evaluation. On muscular palpation, a statistically significant decrease was found on the visual analogic scale value of the middle fibers of the temporalis muscle, temporalis tendon, clavicular and sternal division of the sternocleidomastoid muscle, masseter muscles, and posterior cervical muscles. The temporalis and the masseter muscles showed a significant decrease in the number of subjects with trigger points (TrPs) in all areas in the study group, after treatment. The digastric and sternocleidomastoid muscles also showed a significant reduction in the number of subjects with TrPs. Subjects with MPS and malocclusion were treated using a fixed orthodontic treatment. They showed improvement, although no resolution, in the signs and symptoms of MPS, compared with the untreated control group.     

Duration of stages of the Middle Phalanx Maturation method in a contemporary population: A 6-year longitudinal analysis

Objective

To determine the duration and age at the beginning of each stage corresponding to the circumpubertal period in the Middle Phalanx Maturation method (MPM) and to assess the differences between males and females.

Materials and Methods

Sets of X-rays of the middle phalanx of the third finger taken at 6-month intervals were analysed for 246 skeletal Class I subjects (102 females and 144 males) between 9 and 15 years of age. After staging, the duration of each stage was derived from chronological ages, and the difference between males and females for both duration and age at the beginning of each stage was investigated.

Results

The median duration for MPS2 and MPS3 was 1 year for both sexes, while MPS4 showed a median duration of 1 year in females and 9 months in males, with no significant differences between the sexes. Mean age at the beginning of MPS2 was 10y11m for females and 11y11m for males; for MPS3, it was 11y8m for females and 13y1m for males; for MPS4, it was 12y9m for females and 13y11m for males; for MPS5, it was 13y4m for females and 14y3m for males. The differences between the sexes were statistically significant for all the stages (P < .001).

Conclusions

This study confirms, with relevant sample size, the median duration of 1 year for each MPM stage from MPS2 to MPS4. Despite the distinctive interindividual variability, the interquartile range is 6 months or less for all but one interval, confirming the soundness of the results.     

Myofascial pain syndromes in the maxillofacial area: a common but underdiagnosed cause of head and neck pain

Myofascial pain syndromes (MPS) are a large group of muscular disorders, characterized by the presence of hypersensitive spots called trigger points (TP). The maxillofacial region is a high-frequency area for developing TPs. The aim of this paper was to review and summarize the most important methods of management. A literature review was carried out from Medline and database sources. A range of study types were selected for analysis. TP formation and activity result in a reverberating circuit of sustained neural activity. Central mechanisms, primarily associated with psychosocial factors, lead to chronicity. Other synergistic factors are metabolic disorders, nutritional imbalances and regional anatomic disorders. A detailed history and physical examination are important for proper diagnosis. The aim of MPS management is pain relief and restoration of full muscle function. Treatment may require enhancing central inhibition, using pharmacological and/or behavioural techniques, and reducing peripheral inputs, using physical therapy. There are various effective methods of inactivation of TPs. Recognition and reduction of synergistic factors may be important. MPS have a very high prevalence in the general population, despite low awareness among physicians, affecting patients' quality of life. There is a need for interdisciplinary teams of health professionals to achieve proper diagnosis, management and sustainable outcomes.     

Dental findings in mucopolysaccharidosis type IV A (Morquio's disease type A)

Dental examinations on nine patients with mucopolysaccharidosis type IV A (MPS IV A, Morquio's disease type A) were carried out. Detailed medical, radiologic, and biochemical studies of each case were also performed independently. Dental changes were present in all cases, although the severity varied. The severity of the dental changes did not correlate with the clinical or biochemical findings in all cases. These dental changes are seen only in MPS IV A (N-acetylgalactosamine-6-sulphate sulphatase deficiency) and are not found in MPS IV B (beta-galactosidase deficiency) or the recently delineated MPS IV C (enzyme defect unknown). The dental changes can aid in the diagnosis of patients affected by MPS IV A and are especially useful in mild atypical cases.     

Histologic comparison of healing after ridge preservation using human demineralized bone matrix putty with one versus two different-sized bone particles

Background: Ridge preservation can minimize the loss of alveolar bone subsequent to tooth extraction in preparation for implant therapy. The purpose of this study is to histologically and clinically compare human demineralized bone matrix (DBM) putty with one size of bone particles (SPS) to human DBM putty with two different sizes of bone particles (multiple particle sizes [MPS]) in ridge preservation after molar extractions. Methods: Molar tooth extraction and ridge preservation were performed in 20 participants for each treatment group. Approximately 20 weeks after grafting, core biopsies were obtained during implant placement and analyzed under light microscopy. Specimens were analyzed for the percentage area of vital bone, residual graft particles, and non‐mineralized structures (connective tissue/other non‐mineralized tissue [CT]). Changes in alveolar ridge dimensions were also determined. Results: Sixteen participants in the SPS group and 14 in the MPS group completed the study. The SPS group had a mean of 49% vital bone, 8% residual graft, and 43% CT. The MPS group had 53%, 5%, and 42%, respectively. Patients in both groups lost a mean of <1 mm alveolar height on the buccal and lingual aspects and <1.5 mm of total ridge width. There were no statistically significant differences between the two groups for any clinical or histologic parameters. Conclusion: The results of this study suggest that addition of larger bone particles to DBM putty does not offer additional benefit in the preservation of alveolar bone after the extraction of molar teeth.     

中国1 076名儿童及青年腭中缝影像学分期与其颈椎骨龄分期的相关性研究

目的:通过锥形束CT研究中国儿童及青年腭中缝分期（midpalatal suture stage,MPS）与颈椎骨龄分期（cervical vertebral maturation stage,CS）的相关性,探讨CS对腭中缝骨化闭合程度的预测能力。方法:回顾性收集2013年1月至2018年4月于北京大学口腔医学院·口...     

Evaluation of a mucosal-plaque index (MPS) designed to assess oral care in groups of elderly

An index, called the mucosal-plaque score (MPS), was tested for intra- and inter-examiner agreement at an institution for elderly individuals with mental disabilities. This index was designed to evaluate oral health and oral hygiene in groups of individuals, particularly in hospitals or at other institutions. MPS consists of the sum of a four-point mucosal score (MS) and a four-point plaque score (PS). Intra-examiner agreement was assessed for one dentist (BMH), who examined 24 individuals twice with a one-week interval. Weighted kappa values were 0.60 for MS, 0.62 for PS, and 0.62 for MPS. Inter-examiner agreement between two dentists was conducted by duplicate examinations on 20 persons. Weighted kappa values were 0.47 for MS, 0.71 for PS, and 0.70 for MPS. In a second assessment of Inter-examiner-agreement, eight individuals were each examined by a dentist, two dental hygienists, and one medical nurse. Weighted kappa values were 0.79 for MS, 0.80 for PS, and 0.77 for MPS. These results support the conclusion that the MPS can serve as a reliable measure for the assessment of oral health care in groups of older Individuals .     

Early bond strength of two resin cements to Y-TZP ceramic using MPS or MPS/4-META silanes

For cementation of yttrium-stabilized tetragonal zirconium polycrystal (Y-TZP) ceramic frameworks, protocols of surface-conditioning methods and available cements vary, resulting in confusion among clinicians regarding selection and effects of different conditioning methods on cement adhesion. This study evaluated the effect of two silanes (3-trimethoxysilylpropylmethacrylate (MPS) and 3-trimethoxysilylpropylmethacrylate/4-methacryloyloxyethyl trimellitate anhydride methyl methacrylate (MPS/4-META) on the adhesion of two resin-based cements (SuperBond and Panavia F 2.0) to Y-TZP ceramic and compared several protocols with those indicated by the manufacturer of each of these cements. Disks of Y-TZP ceramic (LAVA, 3M ESPE) (n = 60) were divided into six experimental groups (n = 10 per group) and treated as follows: (1) silica coating (SC) + MPS silane + SuperBond; (2) SC + MPS/4-META + silane + SuperBond); (3) SC + MPS silane + Panavia F 2.0); (4) SC + MPS/4-META silane + Panavia F 2.0); (5) no conditioning + MPS/4-META silane + Super-Bond (SuperBond instructions); and (6) 50-μm Al₂O₃ conditioning + Panavia F 2.0 (Panavia F 2.0 instructions). The specimens were subjected to shear-bond testing after water storage at 37°C for 3 months in the dark. Data were analyzed by analysis of variance and Tukey’s HSD (α = 0.05). After silica coating, the mean bond strength of SuperBond cement was not significantly different between MPS and MPS/4-META silanes (20.2 ± 3.7 and 20.9 ± 1.6 MPa, respectively), but the mean bond strength of Panavia F 2.0 was significantly higher with MPS silane (24.4 ± 5.3 MPa) than with MPS/4-META (12.3 ± 1.4 MPa) (P < 0.001). The SuperBond manufacturer’s instructions alone resulted in significantly higher bond strength (9.7 ± 3.1 MPa) than the Panavia F 2.0 manufacturer’s instruction (0 MPa) (P < 0.001). When silica coating and silanization were used, both SuperBond and Panavia F 2.0 cements demonstrated higher bond strengths they did when the manufacturers’ instructions were followed. With SuperBond, use of MPS or MPS/4-META silane resulted in no significant difference when the ceramic surface was silica coated, but with Panavia F 2.0, use of MPS silane resulted in a significantly higher bond strength than use of MPS/4-META. Use of chairside silica coating and silanization to condition the zirconia surface improved adhesion compared with the manufacturers’ cementation protocols for SuperBond and Panavia F 2.0 resin cements.     

Evaluation of factors related to the success of miniscrew-assisted rapid palatal expansion

ObjectivesTo evaluate whether the success of miniscrew-assisted rapid palatal expansion (MARPE), performed in patients with advanced bone maturation is related to factors such as midpalatal suture (MPS) maturation, age, sex, or bicortical mini-implant anchorage.Materials and MethodsTwenty-eight cone beam computed tomography (CBCT) scans of adults and post-pubertal adolescents treated by MARPE were included in the sample. CBCT images before (T0) and after expansion (T1) were used to evaluate the skeletal changes and the success or failure of MARPE. Axial images of MPS were extracted from T0 and classified into one of the five maturation stages. The correlation between MARPE success and the factors of age, sex, MPS maturation, and bicortical mini-implant anchorage was investigated.ResultsOnly the age showed a statistically significant negative correlation with MARPE success and all the skeletal measures. There was an 83.3% success rate among individuals aged 15 to 19 years, 81.8% from 20 to 29 years, and 20% from 30 to 37 years. MPS maturation showed a negative correlation with the expansion effect. Subjects with stages B or C of MPS maturation showed a 100% success rate, followed by stage D (62.5%) and stage E (58.3%).ConclusionsAs age increased, there was a decrease in MARPE success and the skeletal effects of maxillary expansion. Sex and bicortical mini-implant anchorage were not shown to be relevant factors. There was no correlation between MPS maturation and MARPE success; however, it was observed that all cases of MARPE failure were classified as stage D or E of MPS maturation.     

Bond angle effects on microtensile bonds: laboratory and FEA comparison.

OBJECTIVE: To test the hypothesis that there is a reduction in bond strength when a microtensile load is applied to adhesive junctions prepared at 10, 20 and 30 degrees to the usual perpendicular interface. To evaluate the effect of bond angle and adhesive layer thickness on stress levels within the adhesive joint utilizing FEA. METHODS: Twenty-four non-carious third molars were selected, occlusal enamel removed and polished perpendicular to the long axis of the tooth. The Clearfil SE Bond and Single Bond were applied on the dentin. A 4 mm resin restoration, Z 100, was built up. The teeth were sectioned at 10 degrees, 20 degrees and 30 degrees to the bonding interface (n = 3). The control (n = 3) group had all cuts parallel to the tooth longitudinal axis (0 degrees bond angle). The bond values were calculated in MPa and Two-Way ANOVA and Tukey test applied. FEA was performed (1 mm/side square specimens) to obtain the maximum principal stress (MPS) in the microtensile-model for each bond angle and for varying adhesive thickness from 20 microm to 200 microm for each group. RESULTS: The bond strength results diminish as the angle on the interface increased (P<0.05) for Clearfil SE Bond between 0 (control) and 30 degrees, and for Single Bond between 0 (control) and 10, 20, and 30 degrees. The hypothesis can be fully accepted for Single Bond and partially accepted for Clearfil SE Bond. For the FEA, there was a trend toward decreasing MPS as the bond angle increased, while the MPS for each angled group increased with adhesive layer thickness. SIGNIFICANCE: The MPS results for angled interfaces, exhibited the same trend as the lab values. FEA results indicated an MPS increase with increased adhesive thickness.     

Laboratory and FEA evaluation of dentin-to-composite bonding as a function adhesive layer thickness.

OBJECTIVE: The aim of this study was to test the hypothesis that microtensile bond strength values are inversely proportional to dentin-to-composite adhesive layer thickness through laboratory mechanical testing and finite element analysis. METHOD: Eighteen noncarious third molars were obtained, and occlusal enamel removed perpendicular to the tooth long axis. Two different adhesive systems were utilized as follows (n=3): (1) application of a single layer of Single Bond (3M ESPE Co.) and Clearfil SE Bond (Kuraray Co.) following the manufacturer's directions; (2) application of one layer of both adhesive systems followed by one additional layer; (3) application of one layer of both adhesive systems followed by two additional layers. A 4mm build up was fabricated in increments on each tooth sample (Z 100 composite, 3M ESPE). Section measurements were performed and specimens were separated into three adhesive thickness groups per material (40, 40-80 and 80-120mum) for microtensile testing. The bond strength data (MPa) were analyzed by one-way ANOVA and Tukey test. Maximum principal stresses (MPS) were determined through FEA for three different adhesive layer thicknesses (20, 50 and 100mum). RESULTS: The bond strength data obtained for Single Bond at 0-40mum presented significantly higher values compared to higher adhesive layer thickness groups. There were no statistical differences among bond strength values for all Clearfil SE Bond adhesive layer thicknesses. FEA modeling indicated that MPS increased as adhesive layer increased. The hypothesis was accepted for the Single Bond only. SIGNIFICANCE: Correspondence (not tested statistically) between microtensile laboratory testing and FEA model was only observed for Single Bond as increased adhesive layer thickness did not reduce Clearfil SE Bond strength.     

Finishing and polishing of a hybrid composite and a heat-pressed glass ceramic

This study assessed the finishing and polishing of a hybrid composite and a glass-ceramic. Ninety Tetric specimens were divided into three groups of 30 specimens and finished with three different finishing procedures. The 30 specimens were subsequently subdivided into six groups of five and polished using the following polishing systems: Sof-Lex disks, the Ceramiste kit, a diamond polisher, Diafix-oral, the MPS gel and the Politip system. Seventy-five IPS-Empress specimens were divided into groups of 25 and finished with three different procedures. The 25 specimens were then subdivided into five groups of five and polished with the same systems, except for the Politip technique. The polished surfaces were evaluated quantitatively by laser stylus profilometry with respect to Ra and profile-length-ratio (LR). Qualitative assessment was carried out by SEM. Quantitative results were examined statistically by one- and two-way Anova and LSD test with significance level of 0.05. The lowest roughness on composite specimens was achieved by the MPS gel and Diafix after finishing according to FM 3 and FM 2. With respect to all methods used, there were no significant differences among the five methods with the lowest Ra-values.The ceramic specimens were able to be polished to lower roughness values (p<0.001 for LR). The best results on ceramic surfaces were achieved with the MPS system after finishing according to FM 3 and FM 2. There were no significant differences among the three methods with the lowest Ra-values and the glazed surface. SEM evaluation largely confirmed the quantitative results. Composite specimens exhibited signs of selective resin matrix removal when the Ceramiste system or the Politip system were used.     

Self-assembly of (3-mercaptopropyl)trimethoxysilane on iodine coated gold electrodes

The adsorption of (3-mercaptopropyl)trimethoxysilane (MPS) has been studied on iodine coated gold electrodes. The MPS adsorption from alcoholic solution on Au(111) and iodine coated Au(111) was studied by atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). The electrochemical formation of MPS monolayers was studied by cyclic voltammetry on polycrystalline uncoated and coated gold electrodes with different MPS pre-treatment conditions. Lead electrochemical deposition was used to probe the defect sites of the surfaces created. The MPS-over-iodine coated gold surface produces a lower-density monolayer than the MPS over pure gold. The MPS monolayer formed electrochemically on the iodine coated gold is chemically equal to its counterpart after the iodine desorption. The MPS adsorption occurs via an AuS bond, after the partial reductive-desorption of the iodine monolayer from the iodine coated gold electrode, and produces an ordered composite monolayer of MPS/iodine. The size of the defects can be controlled by varying the electrochemical preparation conditions, using the following reaction: AuI_(ads)+MPSH_(ac)+e⁻↔AuMPS_(ads)+H_(ac)⁺+I_(ac)⁻.     

Real-time augmented model guidance for mandibular proximal segment repositioning in orthognathic surgery,using electromagnetic tracking

It is essential to reposition the mandibular proximal segment (MPS) as close to its original position as possible during orthognathic surgery. Conventional methods cannot pinpoint the exact position of the condyle in the fossa in real time during repositioning. In this study, based on an improved registration method and a separable electromagnetic tracking tool, we developed a real-time, augmented, model-guided method for MPS surgery to reposition the condyle into its original position more accurately.After virtual surgery planning, using a complex maxillomandibular model, the final position of the virtual MPS model was simulated via 3D rotations. The displacements resulting from the MPS simulation were applied to the MPS landmarks to indicate their final postoperative positions. We designed a new registration body with 24 fiducial points for registration, and determined the optimal point group on the registration body through a phantom study. The registration between the patient's CT image and physical spaces was performed preoperatively using the optimal points.We also developed a separable frame for installing the electromagnetic tracking tool on the patient's MPS. During MPS surgery, the electromagnetic tracking tool was repeatedly attached to, and separated from, the MPS using the separable frame. The MPS movement resulting from the surgeon's manipulation was tracked by the electromagnetic tracking system. The augmented condyle model and its landmarks were visualized continuously in real time with respect to the simulated model and landmarks.Our method also provides augmented 3D coronal and sagittal views of the fossa and condyle, to allow the surgeon to examine the 3D condyle–fossa positional relationship more accurately. The root mean square differences between the simulated and intraoperative MPS models, and between the simulated and postoperative CT models, were 1.71 ± 0.63 mm and 1.89 ± 0.22 mm respectively at three condylar landmarks. Thus, the surgeons could perform MPS repositioning conveniently and accurately based on real-time augmented model guidance on the 3D condyle positional relationship with respect to the glenoid fossa, using augmented and simulated models and landmarks.     

Effect of different amounts of 3-methacryloxypropyltrimethoxysilane on the flexural properties and wear resistance of alumina reinforced PMMA

This study evaluated the different amounts of 3-methacryloxypropyltrimethoxysilane (MPS) coated alumina filler particles on flexural strength and wear resistance of alumina reinforced polymethyl methacrylate (PMMA) denture base. Ten mass% of alumina fi ller silanized with 0, 0.1, 0.2, or 0.4 mass% of MPS was blended with PMMA. PMMA without alumina particles served as control.Specimens were prepared for flexural strength and wear resistance tests (n=10). Flexural strength was determined using a 3-point bending test and volume loss was measured by in-vitro 2-body wear-testing. The results were analyzed by One-way ANOVA and Tamhane's test (α=0.05). Flexural strength ranged from 95.1-117.8 MPa, while volume loss ranged from 0.038-0.160 mm³. Statistical analysis indicated the 0.1 mass% MPS silanized group had signifi cantly higher flexural strength and lower volume loss than the control group. Adding alumina filler silanized with 0.1 mass% MPS resulted in an improvement of the flexural strength and wear resistance of PMMA.     

Myofascial pain syndrome of the head and neck: a review of clinical characteristics of 164 patients

Myofascial pain syndrome (MPS) is a common but misunderstood muscular pain disorder involving pain referred from small, tender trigger points within myofascial structures in or distant from the area of pain. Misdiagnosis or inadequate management of this disorder after onset may lead to development of a complex chronic pain syndrome. A review of the clinical characteristics of 164 patients whose chief complaints led to the diagnosis of MPS revealed that these patients had (1) tenderness at points in firm bands of skeletal muscle that were consistent with past reports, (2) specific patterns of pain referral associated with each trigger point, (3) frequent emotional, postural, and behavioral contributing factors, and (4) frequent associated symptoms and concomitant diagnoses.     

Localization of mucopolysaccharides in epithelial-Iike cells cultured in vitro

Previous studies, demonstrating mucopolysaccharides (MPS) in tissue cultured epithelial cells did not eliminate the possibility that some of the reported staining could be attributed to acidic lipids, nucleic acids and substrate movement, although these possibilities were deemed minimal due to the employment of generally accepted techniques. Human amnion cells were grown on coverslips in tissue culture. Some coverslips were treated to remove MPS, lipid or nucleic acids before fixation and staining, whilst others were merely fixed and stained. Fixatives included 10 % formalin. 10 % formalin in 80 % ethanol, 1 % cetylpyridinium chloride and 1 % cetylpyridinium chloride in 80 % ethanol. Stains employed were the Hale colloidal iron, alcian blue, toluidine blue at pH 6.0 and 2.5 and sudan black. Substrate extractions were effected with testicular hyaluronidase, ribonuclease, KOH and pyridirje. The present, report confirms earlier results and provides evidence that human epithelial-like cells produce MPS in vitro the staining specificity of which eliminates lipids and nucleic acids as the source of the observed reactions. It is claimed that the MPS is mainly confined to the cell surface and therefore is more discernible as a MPS stainable moiety in contiguous cell cultures than when cells are dispersed singly.     

Effects of silane coupling agents and solutions of different polarity on PMMA bonding to alumina

The objective of this study was to clarify the effects of silane coupling agents and solutions of different polarity on polymethyl methacrylate (PMMA) bonding to alumina. Three silane coupling agents (3-methacryloxypropyltrimethoxysilane (MPS),3-aminopropyltriethoxysilane (APS) and N-2 (aminoethyl) 3-aminopropyltriethoxysilane) and 3 different polar solutions, 70% ethanol, isopropanol and toluene, were selected for silanization. Shear bond strengths were statistically compared with Tukey HSD(α=0.05). The alumina surfaces after silanization and shear bond test were examined with an energy dispersive spectrometer (EDS).The bond strengths of PMMA on the alumina with MPS (15.0 MPa), APS (13.8 MPa) in ethanol were greater than the others in nonthermocyclings. The bond strength decreased after thermocyclings. The ethanol groups were greater than the others. EDS revealed Si remaining on the alumina surface after the shear bond test. The results indicated that the silanization using MPS and APS with ethanol solution was effective.