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1.
Int J Oral Maxillofac Surg ; 50(2): 227-235, 2021 Feb.
Article in English | MEDLINE | ID: mdl-32605824

ABSTRACT

Bone degradation of the condylar surface is seen in temporomandibular joint osteoarthritis (TMJ OA); however, the initial changes occur in the subchondral bone. This cross-sectional study was performed to evaluate 23 subchondral bone imaging biomarkers for TMJ OA. The sample consisted of high-resolution cone beam computed tomography scans of 84 subjects, divided into two groups: TMJ OA (45 patients with TMJ OA) and control (39 asymptomatic subjects). Six regions of each mandibular condyle scan were extracted for computation of five bone morphometric and 18 grey-level texture-based variables. The groups were compared using the Mann-Whitney U-test, and the receiver operating characteristics (ROC) curve was determined for each variable that showed a statically significance difference. The results showed statistically significant differences in the subchondral bone microstructure in the lateral and central condylar regions between the control and TMJ OA groups (P< 0.05). The area under the ROC curve (AUC) for these variables was between 0.620 and 0.710. In conclusion, 13 imaging bone biomarkers presented an acceptable diagnostic performance for the diagnosis of TMJ OA, indicating that the texture and geometry of the subchondral bone microarchitecture may be useful for quantitative grading of the disease.


Subject(s)
Osteoarthritis , Temporomandibular Joint Disorders , Biomarkers , Cone-Beam Computed Tomography , Cross-Sectional Studies , Humans , Mandibular Condyle , Temporomandibular Joint
2.
J Dent Res ; 98(10): 1103-1111, 2019 09.
Article in English | MEDLINE | ID: mdl-31340134

ABSTRACT

This study's objectives were to test correlations among groups of biomarkers that are associated with condylar morphology and to apply artificial intelligence to test shape analysis features in a neural network (NN) to stage condylar morphology in temporomandibular joint osteoarthritis (TMJOA). Seventeen TMJOA patients (39.9 ± 11.7 y) experiencing signs and symptoms of the disease for less than 10 y and 17 age- and sex-matched control subjects (39.4 ± 15.2 y) completed a questionnaire, had a temporomandibular joint clinical exam, had blood and saliva samples drawn, and had high-resolution cone beam computed tomography scans taken. Serum and salivary levels of 17 inflammatory biomarkers were quantified using protein microarrays. A NN was trained with 259 other condyles to detect and classify the stage of TMJOA and then compared to repeated clinical experts' classifications. Levels of the salivary biomarkers MMP-3, VE-cadherin, 6Ckine, and PAI-1 were correlated to each other in TMJOA patients and were significantly correlated with condylar morphological variability on the posterior surface of the condyle. In serum, VE-cadherin and VEGF were correlated with one another and with significant morphological variability on the anterior surface of the condyle, while MMP-3 and CXCL16 presented statistically significant associations with variability on the anterior surface, lateral pole, and superior-posterior surface of the condyle. The range of mouth opening variables were the clinical markers with the most significant associations with morphological variability at the medial and lateral condylar poles. The repeated clinician consensus classification had 97.8% agreement on degree of degeneration within 1 group difference. Predictive analytics of the NN's staging of TMJOA compared to the repeated clinicians' consensus revealed 73.5% and 91.2% accuracy. This study demonstrated significant correlations among variations in protein expression levels, clinical symptoms, and condylar surface morphology. The results suggest that 3-dimensional variability in TMJOA condylar morphology can be comprehensively phenotyped by the NN.


Subject(s)
Artificial Intelligence , Cone-Beam Computed Tomography , Osteoarthritis/diagnosis , Temporomandibular Joint Disorders/diagnosis , Adult , Biomarkers/analysis , Case-Control Studies , Humans , Middle Aged , Temporomandibular Joint/diagnostic imaging , Temporomandibular Joint/physiopathology
3.
Int J Oral Maxillofac Surg ; 48(6): 739-745, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30712988

ABSTRACT

The aim of this study was to quantify three-dimensional condylar displacements as a result of two-jaw surgery for open bite correction in patients with skeletal class II and class III malocclusion. Pre-surgical (T1) and post-surgical (T2) cone beam computed tomography scans were taken for 16 patients with skeletal class II (mean age 22.3±9.47years) and 14 patients with skeletal class III (mean age 25.6±6.27years). T2 scans were registered to T1 scans at the cranial base. Translational and rotational condylar changes were calculated by x,y,z coordinates of corresponding landmarks. The directions and amounts of condylar displacement were assessed by intra- and inter-class Mann-Whitney U-test or t-test. Class II patients presented significantly greater amounts of lateral (P=0.002) and inferior (P=0.038) translation than class III patients. The magnitudes of condylar translational displacements were small for both groups. Skeletal class III patients had predominantly medial (P=0.024) and superior (P=0.047) condylar translation. Skeletal class II patients presented greater condylar counterclockwise pitch (P=0.007) than class III patients. Two-jaw surgery for the correction of open bite led to different directions and amounts of condylar rotational displacement in patients with skeletal class II compared to class III malocclusion, with greater rotational than translational displacements.


Subject(s)
Malocclusion, Angle Class III , Open Bite , Adolescent , Adult , Child , Cone-Beam Computed Tomography , Humans , Imaging, Three-Dimensional , Mandible , Mandibular Condyle , Young Adult
4.
Orthod Craniofac Res ; 20(3): 152-163, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28660731

ABSTRACT

OBJECTIVE: To evaluate the influence of the maturational stages of zygomaticomaxillary sutures (ZMS) on the response to maxillary protraction. SUBJECTS AND METHODS: A total of 40 Class III patients were treated retrospectively with either a combination of rapid maxillary expansion and facial mask (RME/FM) or bone-anchored maxillary protraction (BAMP). The RME/FM group consisted of 18 patients (mean age 8.3 years), while the BAMP group was comprised of 22 patients (mean age 11.8 years). The initial CBCT images (T1) of the ZMSs were classified blindly. 3D models from CBCT images at the start and at the end of orthopaedic treatment were registered on the anterior cranial base, and corresponding structures were measured on colour-coded maps and semitransparent overlays. The amounts of protraction of the maxilla, zygoma, orbitale and maxillary first molars for both groups were analysed with two-way ANOVA with Holm-Sidak post hoc test for multiple comparisons. RESULTS: A significant association was found between the early maturation stages of the ZMSs and the amount of maxillary protraction, regardless of the protraction method used. Class III patients with ZMS stages A and B showed greater maxillary protraction than patients at stage C. CONCLUSION: The maturational stages of ZMS are associated with the response maxillary protraction.


Subject(s)
Cranial Sutures/growth & development , Extraoral Traction Appliances , Malocclusion, Angle Class III/therapy , Maxillofacial Development , Orthodontic Anchorage Procedures/methods , Palatal Expansion Technique , Adolescent , Brazil , Child , Child, Preschool , Cone-Beam Computed Tomography , Cranial Sutures/diagnostic imaging , Female , Humans , Male , Malocclusion, Angle Class III/diagnostic imaging , Models, Dental , Reproducibility of Results , Retrospective Studies , Tooth, Deciduous
5.
Orthod Craniofac Res ; 20(2): 111-118, 2017 May.
Article in English | MEDLINE | ID: mdl-28414870

ABSTRACT

OBJECTIVES: Three-dimensional evaluation of skeletal mandibular changes following Herbst appliance treatment. SETTING AND SAMPLE POPULATION: Retrospective case-control study, based on a sample size calculation. Twenty-five pubertal patients treated with Herbst appliance (HAG), and 25 matched Class II patients who received other non-orthopaedic dental treatments (CG). MATERIAL AND METHODS: Three-dimensional models were generated from pre-treatment (T0) and post-treatment (T1) cone beam computed tomograms. Volumetric registration on the cranial base was used to assess mandibular displacement; volumetric regional registration was performed to evaluate mandibular growth. Quantitative measurements of X, Y, Z and 3D Euclidian changes, and also qualitative visualization by colour-mapping and semi-transparent overlays were obtained. RESULTS: Downward displacement of the mandible was observed in both HAG and CG (2.4 mm and 1.5 mm, respectively). Significant forward displacement of the mandible was observed in the HAG (1.7 mm). HAG showed greater 3D superior and posterior condylar growth than the CG (3.5 mm and 2.0 mm, respectively). Greater posterior growth of the ramus was noted in the HAG than in CG. CONCLUSIONS: Immediately after Herbst therapy, a significant mandibular forward displacement was achieved, due to increased bone remodelling of the condyles and rami compared to a comparison group. Three-dimensional changes in the direction and magnitude of condylar growth were observed in Herbst patients.


Subject(s)
Bone Remodeling/physiology , Cone-Beam Computed Tomography , Imaging, Three-Dimensional , Malocclusion, Angle Class II/therapy , Mandible/diagnostic imaging , Mandible/growth & development , Orthodontic Appliances, Functional , Adolescent , Case-Control Studies , Child , Female , Humans , Male , Models, Dental , Retrospective Studies , Treatment Outcome
7.
Clin Pharmacol Ther ; 95(4): 432-8, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24419562

ABSTRACT

This study aimed to evaluate the effects of green tea on the pharmacokinetics and pharmacodynamics of the ß-blocker nadolol. Ten healthy volunteers received a single oral dose of 30 mg nadolol with green tea or water after repeated consumption of green tea (700 ml/day) or water for 14 days. Catechin concentrations in green tea and plasma were determined. Green tea markedly decreased the maximum plasma concentration (C(max)) and area under the plasma concentration-time curve (AUC(0-48)) of nadolol by 85.3% and 85.0%, respectively (P < 0.01), without altering renal clearance of nadolol. The effects of nadolol on systolic blood pressure were significantly reduced by green tea. [(3)H]-Nadolol uptake assays in human embryonic kidney 293 cells stably expressing the organic anion-transporting polypeptides OATP1A2 and OATP2B1 revealed that nadolol is a substrate of OATP1A2 (Michaelis constant (K(m)) = 84.3 µmol/l) but not of OATP2B1. Moreover, green tea significantly inhibited OATP1A2-mediated nadolol uptake (half-maximal inhibitory concentration, IC(50) = 1.36%). These results suggest that green tea reduces plasma concentrations of nadolol possibly in part by inhibition of OATP1A2-mediated uptake of nadolol in the intestine.


Subject(s)
Adrenergic beta-Antagonists/pharmacokinetics , Catechin/pharmacokinetics , Food-Drug Interactions , Nadolol/pharmacokinetics , Tea/chemistry , Adrenergic beta-Antagonists/pharmacology , Adult , Area Under Curve , Blood Pressure/drug effects , Cross-Over Studies , Female , HEK293 Cells , Humans , Inhibitory Concentration 50 , Intestinal Mucosa/metabolism , Male , Nadolol/pharmacology , Organic Anion Transporters/metabolism , Young Adult
8.
Pharmazie ; 68(9): 777-81, 2013 Sep.
Article in English | MEDLINE | ID: mdl-24147348

ABSTRACT

Cisplatin, cis-Dichlorodiammine platinum (II) (CDDP) remains a major antineoplastic drug for the treatment of solid tumors. Its chief dose-limiting side effect is nephrotoxicity. To make a safe and effective dosing regimen of a drug excreted mainly by the renal route, evaluation of patients' renal function is essential. Creatinine clearance (CLcr) or glomerular filtration rate (GFR) is considered to be a standard renal-function test. Several equations have been used in clinical settings, to predict CLcr and GFR using serum creatinine concentration. We carried out a retrospective analysis of the correlation between 24-hour CLcr measured by a urine collection method; and the predicted CLcr and GFR estimated by various equations such as Jelliffe, Yasuda, Orita, Mawer, Mawer, MDRD and modified MDRD, and Cockcroft-Gault. This study used data from Japanese head-and-neck cancer patients, before and after chemotherapy with CDDP. Slopes of regression lines of scatter plots between measured CLcr and predicted renal function in post-CDDP patients were less compared to pre-CDDP patients. On the other hand, Y-intercepts were noted in the scatter plots on renal function from all equations. These results suggest that evaluation of renal function using predictive formulae may have been over-/under-estimated after CDDP administration.


Subject(s)
Antineoplastic Agents/adverse effects , Cisplatin/adverse effects , Kidney Function Tests , Kidney/drug effects , Adult , Aged , Aged, 80 and over , Antineoplastic Agents/therapeutic use , Asian People , Cisplatin/therapeutic use , Creatinine/urine , Female , Glomerular Filtration Rate , Head and Neck Neoplasms/complications , Head and Neck Neoplasms/drug therapy , Humans , Male , Middle Aged , Reproducibility of Results , Retrospective Studies , Young Adult
9.
J Nutr Health Aging ; 15(4): 282-6, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21437560

ABSTRACT

OBJECTIVES: To determine the presence or extent of arginine deficiency in pressure ulcer (PU) patients on percutaneous endoscopic gastrostomy (PEG) feeding and to examine the effects of arginine supplementation on PU healing. DESIGN: All eligible PEG patients, with and without PU, were cross-sectionally assessed for plasma arginine. Three-month supplementation with arginine-enriched water (Arginaid Water) was performed on a subset of patients with PU. This intervention study was a prospective, non-controlled trial with 5 PU patients. SETTING: Geriatric ward of a rural clinical hospital in Japan. PARTICIPANTS: Thirty-nine inpatients with PEG feeding were assessed for plasma arginine. Five of the 13 patients with PU and five of 26 patients without PU underwent amino acid profiling. INTERVENTION: Five of the patients with PU received Arginaid Water supplementation. MEASUREMENTS: Plasma amino acid measurements and biochemical analyses were performed. For those with PU on Arginaid Water supplementation, plasma arginine concentration and PU status were monitored every month. RESULTS: Patients with PU showed significantly lower plasma arginine concentration compared to those without PU (control vs. PU; 80.2±21.3 vs 62.8±14.7 nmol/ml, p<0.01). After the addition of Arginaid Water, plasma arginine concentration increased (before vs 3 months later; 57.9±1.8 vs 83.1±8.5, p<0.01), and PU area, perimeter, DESIGN-R and PUSH scores significantly improved. CONCLUSION: Plasma arginine was lower in PEG patients with PU. The healing rate of PU is improved with Arginaid Water supplementation. The findings from this study support the use of arginine supplementation in PEG patients with PU.


Subject(s)
Arginine/blood , Arginine/therapeutic use , Enteral Nutrition , Pressure Ulcer/blood , Pressure Ulcer/drug therapy , Wound Healing/drug effects , Aged, 80 and over , Analysis of Variance , Arginine/deficiency , Cross-Sectional Studies , Dietary Supplements , Enteral Nutrition/adverse effects , Female , Humans , Male , Pressure Ulcer/pathology , Prospective Studies , Treatment Outcome , Wound Healing/physiology
10.
J Oral Rehabil ; 28(2): 180-5, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11298268

ABSTRACT

The purpose of this study was to clarify the effect of the reducing agent on the oxygen-inhibited layer of the cross-linked reline material. A commercial autopolymerizing reline resin containing 1,6-hexanediol dimethacrylate as cross-linking agent and 1 wt.% sodium sulphite solution as a reducing agent was prepared. The inhibited layer was observed using an optical transmission microscope under the conditions of the application of sodium sulphite for 0, 1, 5 and 15 min after curing for 10 min in air. As a control, the reline material was cured on sealing from air. Moreover, the three-point flexural strength test was performed under the same conditions. The fracture was then observed using scanning electron microscopy (SEM). Although hardness of the inhibited layer was enhanced after the application of the reducing agent, the layer was still observed. The flexural strength of the control and the groups after application of the reducing agent was significantly higher than the group without reducing agent. SEM examination revealed many polymer beads on the group without reducing agent, whereas polymer beads could not be observed on the groups applying the reducing agent. These results indicated that the application of sodium sulphite was effective in hardening the surface unpolymerized zone.


Subject(s)
Antioxidants/chemistry , Cross-Linking Reagents/chemistry , Dental Materials/chemistry , Denture Rebasing , Methacrylates/chemistry , Sulfites/chemistry , Analysis of Variance , Denture Liners , Elasticity , Hardness , Humans , Materials Testing , Methylmethacrylates/chemistry , Microscopy, Electron, Scanning , Oxidation-Reduction , Pliability , Polymers/chemistry , Powders , Statistics as Topic , Surface Properties , Time Factors
11.
J Oral Rehabil ; 28(1): 64-7, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11298911

ABSTRACT

The purpose of this study was to investigate the association of temporomandibular joint (TMJ) clicking with the types of canine guidance, the tracing patterns of mandibular laterotrusion and, especially, with the movements of the working side condyle. In a young subject group, the movements of left and right mandibular laterotrusion were measured at the incisal and the lateral pole point of the working side condyle. All samples were divided into one of two groups according to the mesial (M) or distal (D) canine guidance. They were also divided into protrusive laterotrusion (PL) or retrusive laterotrusion (RL) groups according to the tracing patterns. The incidence of clicking was 23.8% in all 84 TMJs. There was no significant difference between the M and the D groups. However, clicking occurrence was significantly higher in the RL than in the PL group (P<0.05). The condyles in clicking joints moved more posterior in ipsilateral laterotrusion than the condyles in non-clicking joints. The condyles in RL also moved more posterior than those in PL. It is suggested that the posterior movement of the working side condyle in RL has a strong relationship with the internal derangement of the TMJ. However, it is not related to the type of canine guidance.


Subject(s)
Mandible/physiology , Temporomandibular Joint/physiology , Adult , Chi-Square Distribution , Cuspid/physiology , Dental Occlusion , Electronics, Medical/instrumentation , Female , Humans , Incidence , Incisor/physiology , Jaw Relation Record , Male , Mandible/anatomy & histology , Mandibular Condyle/anatomy & histology , Mandibular Condyle/physiology , Movement , Optics and Photonics/instrumentation , Sound , Statistics as Topic , Temporomandibular Joint/anatomy & histology
12.
J Oral Rehabil ; 27(10): 911-7, 2000 Oct.
Article in English | MEDLINE | ID: mdl-11065027

ABSTRACT

The effect of different types of canine guidance on the patterns of laterotrusive tracing at the incisal point and the relationship between the laterotrusive inclinations and the working side condylar movements were investigated in 42 young subjects. The subjects were divided into M and D groups according to their mesial and distal canine guidance, and were also divided into protrusive laterotrusion (PL) and retrusive laterotrusion (RL) groups according to their laterotrusive tracing patterns. No differences of laterotrusive inclinations and working side condylar movements were found between the M and D groups. The laterotrusive tracing pattern had no corresponding association with the type of canine guidance. In relation to the movements of the working side condyles, significant differences were found between the PL and RL groups. The condyles moved laterally and posteriorly in the RL group, but moved lateral and inferior in the PL one. The distance of condylar movement in the X direction was correlated with the horizontal and sagittal inclinations of laterotrusion. The results indicate that the movements of the working side condyle were affected functionally by the laterotrusion, but not by either the mesial or the distal type of canine guidance.


Subject(s)
Cuspid/physiology , Dental Occlusion , Mandibular Condyle/physiology , Adult , Chi-Square Distribution , Female , Humans , Jaw Relation Record , Male , Mandible/physiology , Movement , Range of Motion, Articular , Reference Values , Statistics, Nonparametric , Temporomandibular Joint/physiology
13.
Int J Prosthodont ; 12(2): 129-34, 1999.
Article in English | MEDLINE | ID: mdl-10371914

ABSTRACT

PURPOSE: The purpose of this study was to clarify certain properties of the resulting unpolymerized surface layer on 6 hard, autopolymerizing reline resins. MATERIALS AND METHODS: Two of the resins examined were the conventional type with a base monomer composition of mainly methyl methacrylate, and the other four were cross-linked reline materials containing difunctional monomers. For curing, the materials were polymerized in air at 24 and 37 degrees C, and in distilled water at 37 degrees C. The powder-to-liquid ratio was changed by +/- 20 wt% of the manufacturer's specified ratio. The inhibition depth processed under these conditions was measured with an optical microscope. Each sample was then immersed in methylene blue dye bath for 3 weeks before its surface was observed. RESULTS: Especially on cross-linked reline materials, the unpolymerized layer was significantly reduced with higher temperature, lower oxygen presence, and lower powder-to-liquid ratio (P < 0.01). The unpolymerized layer was stained in all materials. There were tiny, stained voids in the polymerized region on the conventional type of reline resins, whereas no staining was found in the polymerized region on the cross-linking reline resins. CONCLUSION: The inhibition depth was strongly affected by the temperature, the presence of air, and viscosity. The unpolymerized layer was easily contaminated in all materials. However, the highly polymerized, cross-linked reline materials might be harder to contaminate than the conventional type of reline resins.


Subject(s)
Denture Rebasing , Polymethyl Methacrylate/chemistry , Analysis of Variance , Cross-Linking Reagents/chemistry , Denture Liners , Materials Testing , Methylmethacrylates/chemistry , Polymers/chemistry , Porosity , Surface Properties , Viscosity
14.
Med Pediatr Oncol ; 32(4): 259-6, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10102019

ABSTRACT

BACKGROUND: Prevention of central nervous system (CNS) leukemia by early introduction of therapy to this sanctuary site is an essential component of modern treatment strategy for acute lymphoblastic leukemia (ALL). However, the optimal form of preventive CNS therapy remains debatable. PROCEDURE: To address this issue, we evaluated the efficacy of CNS preventive therapy for 572 children with ALL who achieved complete remission in the Children's Cancer and Leukemia Study Group (CCLSG) ALL874 (1987-1990) and ALL911 (1991-1993) studies. They received risk-directed therapy based on age and leukocyte count. In the ALL 874 study, the non-high-risk (low-risk [LR] + intermediate risk [IR]) patients were randomly assigned to the conventional cranial irradiation (CRT) regimen (L874A and I874A) and the high-dose methotrexate (HDMTX) regimen without CRT (L874B and I874B). The former patients received 18-Gy CRT plus 3 doses of intrathecal (i.t.) MTX and the latter patients received 3 courses of HDMTX at 2 g/m2 plus 13 doses of ITMTX (L874B) or 4 courses of HDMTX at 4.5 g/m2 plus 1 dose of ITMTX (I874B). RESULTS: The 7-year probabilities (+/- SE) of CNS relapse-free survival were 97.3% +/- 2.6% (L874A, n = 41) vs. 90.3% +/- 5.3% (L874B, n = 39) (P = 0.25) in the LR patients, and 100% (I874A, n = 55) vs. 78.5% +/- 6.5% (I874B, n = 54) (P = 0.002) in the IR patients. The corresponding disease-free survival (DFS) rates were 79.4% +/- 6.5% vs. 74.4% +/- 7.3% (P = 0.62) in the LR group and 63.3% +/- 6.8% vs. 58.3% +/- 7.2% (P = 0.66) in the IR group. Thus, the HDMTX regimen could not provide better protection of CNS relapse as compared with the CRT regimen, although their overall efficacy was not significantly different. In the ALL 911 study, intensive systemic chemotherapy with extended i,t, injections of MTX plus cytarabine achieved a high CNS relapse-free survival (98% +/- 1.9% at 7 years) and a favorable DFS (85.5% +/- 5% at 7 years) in the IR patients. The patients in the high-risk (HR) group in both ALL874 and ALL911 studies received the 18-Gy or 24-Gy CRT with intensive systemic chemotherapy. Their 7-year probabilities of CNS relapse-free survival ranged from 88% to 95%, among which the T-ALL patients had a risk of CNS leukemia, which was 3-4 times higher compared with B-precursor ALL patients. CONCLUSIONS: These results indicate that long-term intrathecal CNS prophylaxis as well as appropriate systemic therapy for the non-high-risk patients can provide protection against CNS relapse equivalent to that provided by cranial irradiation.


Subject(s)
Antimetabolites, Antineoplastic/administration & dosage , Central Nervous System Neoplasms/drug therapy , Central Nervous System Neoplasms/radiotherapy , Methotrexate/administration & dosage , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Precursor Cell Lymphoblastic Leukemia-Lymphoma/pathology , Adolescent , Adult , Central Nervous System Neoplasms/secondary , Child , Child, Preschool , Disease-Free Survival , Drug Administration Schedule , Female , Humans , Infant , Injections, Spinal , Japan , Male , Radiotherapy, Adjuvant , Treatment Outcome
15.
J Med Dent Sci ; 46(3): 111-6, 1999 Sep.
Article in English | MEDLINE | ID: mdl-12160256

ABSTRACT

Recent studies and literature reviews of temporomandibular disorders (TMD) do not strongly support the role of occlusal etiologic factors. For this paper we collected and classified studies dealing with occlusion as a contributing factor to TMD through reviews, and discussions of these difficulties and possible solutions. Related articles from 275 papers covering nearly the past twenty years were selected from a prosthetic point of view and reviewed. The validity and reliability of occlusal examinations, however, are questionable since the epidemiological studies dealt with numerous varied subjects. Although occlusal relationships, such as overbite, non-working side interferences, and discrepancy between the intercuspal position and the retruded contact position, have often been considered as contributing factors of TMD, there is no consistency among even those studies that support such an occlusal factor. A project should be initiated to create a revised, precise and practical method to determine the occlusal contact and to categorize an occlusal contact scheme. To detect whether the patients' occlusal scheme works traumatically or not should be an important part of the occlusal examination. That is, the frequency and duration of tooth contact on the occlusal scheme should be studied.


Subject(s)
Dental Occlusion , Temporomandibular Joint Disorders/etiology , Adolescent , Adult , Child , Craniomandibular Disorders/etiology , Dental Occlusion, Traumatic/complications , Dental Prosthesis , Epidemiologic Studies , Female , Humans , Male , Malocclusion/classification , Malocclusion/complications , Mandible/physiopathology , Masticatory Muscles/physiopathology , Movement , Reproducibility of Results , Risk Factors , Temporomandibular Joint Disorders/classification , Tooth/physiology , Tooth Loss/complications
16.
Rinsho Ketsueki ; 39(8): 565-73, 1998 Aug.
Article in Japanese | MEDLINE | ID: mdl-9785974

ABSTRACT

To clarify the efficacy of modern intensive chemotherapy for ALL patients with unfavorable features, we compared the time to failure and initial clinical features of children who relapsed in the bone marrow or combined sites, as documented by early CCLSG studies (H811 and H851; 1981-1987) and later studies (H874 and H/HH911; 1987-1993) concerning high-risk ALL patients. In the later studies patients outcomes with new intensive regimens employing early intensification and reinduction therapy were apparently better than those of patients in the early studies with conventional regimens. When we compared the number of relapsed patients based on duration of first remission, we found that the improved outcomes for patients in the later studies were due to a decrease in the number who relapsed 7-36 months after the start of treatment (intermediate relapse), and that the percentage of those who relapsed within the first 6 months of therapy (early relapse) was higher. Patients with high initial WBC counts tended to relapse much earlier than those with low initial WBC counts. However, in the later studies, patients with high WBC counts often relapsed after the termination of therapy (late relapse). These results suggest that the intensive chemotherapy regimens used in the later studies can prevent the development of drug resistant leukemic clones, except in extremely high-risk patients likely to relapse within the first 6 months of therapy.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Bone Marrow Neoplasms/etiology , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Child , Child, Preschool , Female , Humans , Male , Precursor Cell Lymphoblastic Leukemia-Lymphoma/pathology , Recurrence , Risk , Time Factors
17.
J Oral Rehabil ; 25(7): 507-12, 1998 Jul.
Article in English | MEDLINE | ID: mdl-9722097

ABSTRACT

The purpose of this study was to investigate the influence of some demographic and clinical variables on psychosomatic traits of the patients who visited the prosthodontic section of the Dental Hospital at Tokyo Medical and Dental University for replacement of their removable partial dentures (RPDs). Sixty-six patients with 50 maxillary and 44 mandibular RPDs completed the psychological measurements concerning their dentures using visual analogue scales (VAS). Female patients rated significantly lower satisfaction with the comfort of their dentures than males. Younger patients expressed less satisfaction with the aesthetics of their dentures than the older patients. The period of wearing the present denture significantly correlated with psychological measures of pain, comfort, and general satisfaction, suggesting that this clinical variable may be an important factor. There was no significant correlation between the patients' general satisfaction with dentures and the retention/stability scores assessed by the examiner.


Subject(s)
Denture, Partial, Removable/psychology , Adult , Age Factors , Aged , Denture Retention , Female , Humans , Male , Middle Aged , Pain Measurement , Patient Satisfaction , Retreatment , Sex Factors , Statistics, Nonparametric , Time Factors
18.
Kokubyo Gakkai Zasshi ; 65(2): 196-201, 1998 Jun.
Article in Japanese | MEDLINE | ID: mdl-9711038

ABSTRACT

The Department of Health of Okinawa Prefecture with the cooperation of the Ministry of Health and Welfare and eight Dental Schools in Japan, is performing dental treatment and oral health care on inhabitants in areas of Okinawa where no dentists are present. We were asked to offer dental treatment and oral health care for the inhabitants of Tokashiki Island, Okinawa from June 30 to July 29, 1997. The DMF rates of school children of Tokashiki Island was much higher than the average rates in Japan. Among the treatment procedures, conservative treatment was 72.5%, most of which was composite resin filling. Most middle-aged persons had severe periodontal disease rather than severe dental caries. Patients, who suffered from severe dental caries chose extraction of their teeth rather than conservative treatment. The denture wearers of Tokashiki Island used their dentures longer than those who visited our Prosthodontic Department. They were not necessarily dissatisfied with their dentures, but their alveolar ridges were absorbed extensively. These conditions could be due to not only patients' consciousness but also the lack of dental hygiene education. It seems that primary prevention and higher dental hygiene education are needed for the inhabitants of Tokashiki Island where dental treatment must be done in a short time.


Subject(s)
DMF Index , Medically Underserved Area , Oral Hygiene Index , Periodontal Diseases/epidemiology , Tooth Diseases/epidemiology , Adolescent , Adult , Aged , Child , Child, Preschool , Dental Caries , Health Education , Humans , Infant , Japan , Middle Aged , Periodontal Diseases/prevention & control , Periodontal Diseases/therapy , Tooth Diseases/prevention & control , Tooth Diseases/therapy
19.
J Dent Res ; 76(2): 714-9, 1997 Feb.
Article in English | MEDLINE | ID: mdl-9062566

ABSTRACT

Little is known about the detailed kinematics of the human temporomandibular condyle during jaw opening and closing. According to the rotate and swing model by Osborn (1989), the condyle is kept in close contact with the articular eminence during opening. Whether the condyle is in closer contact with the articular eminence during opening than during closing is unknown. Another consequence of the model is that the opening condylar movements are less variable than the closing movements. In this study, the hypothesis that the opening condylar path is closer to the articular eminence and also less variable than the closing condylar path is tested. Twenty subjects (10 males and 10 females with a mean age of 22) without signs or symptoms of a craniomandibular disorder performed 2 series of 4 protrusive movements and 2 series of 4 empty opening-closing movements. The movements were recorded by a six-degrees-of-freedom opto-electronic jaw movement recording system (OKAS-3D). The kinematic center of the condyle was used as a reference point for the reconstruction of condylar movement paths. Characteristics of the opening and closing paths were investigated by means of a displacement index (DI). This index is the quotient between the three-dimensional path length and the three-dimensional path distance between the start and the end point of an opening or closing movement of the kinematic center. The DI was smaller (p < 0.0001) and also less variable (p < 0.0001) during opening than during closing. The smaller DI value, in combination with the concave nature of the movement path, indicates that the opening path of the kinematic center lies above the closing path and thus closer to the articular eminence.


Subject(s)
Mandibular Condyle/physiology , Adolescent , Adult , Analysis of Variance , Biomechanical Phenomena , Dental Articulators/statistics & numerical data , Female , Humans , Male , Malocclusion, Angle Class I/physiopathology , Movement , Statistics, Nonparametric , Temporomandibular Joint/physiology
20.
J Dent Res ; 74(10): 1644-8, 1995 Oct.
Article in English | MEDLINE | ID: mdl-7499586

ABSTRACT

The kinematic center of the temporomandibular condyle is that condylar point which follows as much as possible the same movement path during different types of mandibular movements. In this study, the location of the kinematic center with respect to the palpated lateral pole of the condyle was investigated. Also, the lengths of the condylar movement path reconstructed by means of the kinematic center and the palpated condyle were compared. Mandibular movements were recorded with 6 degrees of freedom in 20 healthy subjects. A software procedure calculated the location of the kinematic center as that mandibular point for which the protrusive and opening movement path showed a minimal difference. For each subject, its average location was calculated on the basis of 16 pairs of protrusive and opening movements. The kinematic center was located posteriorly and superiorly with respect to the palpated condylar point (p < 0.0001). The standard deviation in the anterior-posterior coordinate of the average kinematic center was smaller than that in the superior-inferior coordinate (p < 0.0001). During opening, the path length of the kinematic center is longer than that of the palpated lateral pole of the condyle (p < 0.0001). In contrast to left-right differences found in the path lengths of the lateral pole of the condyle, no left-right differences were found for the kinematic center.


Subject(s)
Mandibular Condyle/physiology , Temporomandibular Joint/physiology , Adolescent , Adult , Biomechanical Phenomena , Female , Humans , Male , Malocclusion, Angle Class I/physiopathology , Movement , Reference Values , Software , Statistics, Nonparametric
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