Quantitative bone imaging biomarkers to diagnose temporomandibular joint osteoarthritis

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.

Minimally Invasive Approach for Diagnosing TMJ Osteoarthritis

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.

Three-dimensional analysis of condylar changes in surgical correction for open bite patients with skeletal class II and class III malocclusions

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.

Reliability of predicted renal function in Japanese patients on cisplatin therapy

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.

Effect of the reducing agent on the oxygen-inhibited layer of the cross-linked reline material

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.

The relation of mandibular laterotrusion with ipsilateral TMJ clicking

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.

The relation of canine guidance with laterotrusive movements at the incisal point and the working side condyle

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.

What types of occlusal factors play a role in temporomandibular disorders...? A literature review

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.

Improvement in CNS protective treatment in non-high-risk childhood acute lymphoblastic leukemia: report from the Japanese Children's Cancer and Leukemia Study Group

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.

Unpolymerized layer on autopolymerizing, hard reline materials

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.

[Bone marrow relapse in high-risk pediatric patients with acute lymphoblastic leukemia: a comparison of relapse times and initial clinical features of patients on different protocols. Children's Cancer and Leukemia Study group (CCLSG)]

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.

The influence of some demographic and clinical variables on psychosomatic traits of patients requesting replacement removable partial dentures

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.

[Oral conditions of inhabitants in Tokashiki Island, Okinawa]

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.

Movements of the mandibular condyle kinematic center during jaw opening and closing

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.

The kinematic center: a reference for condylar movements

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.

[Erythroleukemia in pregnancy with successful outcome of delivery]

A 37-year-old woman was admitted to our hospital because of anemia in the 33rd week of pregnancy. On admission, the hemoglobin was 7.6 g/dl, platelets 508,000/microliters and WBC 8,300/microliters with 4% blast cells. Bone marrow aspirate demonstrated 50% erythroblasts of nucleated cells, which had prominent megaloid and polynucleic changes, and 20% myeloblast cells. We diagnosed her as having erythroleukemia. Receiving packed-red-cell transfusions, she had a cesarean section, and gave birth to a female infant (BW 2,175 g) in the 34th week of pregnancy. At the same time, she had a total hysterectomy with left adnexectomy. The postoperative course was favorable. She had a combination chemotherapy of BHAC-DMP, resulting in a partial remission. After the second induction chemotherapy with subcutaneous use of G-CSF and BHAC-DMP, complete remission was obtained, which lasted for almost 17 months. The child is growing well without any hematological disorder.

[Study on measurement of dynamic viscoelasticity of maxillary mucosa]

The purpose of this study is to investigate the viscoelastic properties of the oral mucosa. The handy apparatus which can easily show the rheological properties (i.e., G', G", tan delta) was made for the trial. The principle of this apparatus is to measure the stress and the phase difference produced when the constant sinusoidally oscillating shear deformation is loaded on the viscoelastic materials. This handy trial apparatus was found to be applicable in vivo, as evaluated by the dynamic spectrometers. The viscoelastic properties of the mucosa of the maxilla were investigated with this apparatus. The results were as follows: 1) Viscoelastic values varied in individual cases. 2) In the maxillary ridge area and the median portion, the values of modulus G and tan delta were low. In other words, the stiffness of these areas was low and the recovery from deformation was fast. 3) The values of modulus G and tan delta were high in the side region of the palate. The result showed that in this area there was a high stiffness and the recovery from deformation was slow. 4) In the incisive papilla and the area of flabby gum, the values of modulus G were low and the values of tan delta were high. The low stiffness and the slow recovery from deformation were shown in these areas.

Masked Ph chromosome due to a new type of translocation in a patient with chronic myelogenous leukemia

A chronic myelogenous leukemia patient with a masked Ph chromosome due to a new type of translocation, t(9;11;22)(q34;p11;q11), is reported.

Comparison of intermittent or continuous methotrexate plus 6-mercaptopurine in regimens for standard-risk acute lymphoblastic leukemia in childhood (JCCLSG-S811). The Japanese Children's Cancer and Leukemia Study Group

From 1981 to 1983, 131 previously untreated patients with acute lymphoblastic leukemia (ALL) standard-risk group were entered to the protocol JCCLSG-S811. Of 119 eligible patients, 115 (96.6%) attained complete remission by treatment with prednisone (PRD) plus vincristine (VCR) or vindesine (VDS). After preventive central nervous system (CNS) therapy including 18 Gy cranial irradiation and three doses of intrathecal methotrexate (MTX), the patients were assigned randomly to the two maintenance chemotherapies, Regimen A and Regimen B. Regimen A (intermittent regimen) consisted of PRD (120 mg/m2/day by mouth for 5 days) plus 6-mercaptopurine (6MP) (175 mg/m2/day by mouth for 5 days) plus VCR (2.0 mg/m2 intravenously) alternating biweekly with MTX (225 mg/m2 intravenously). Regimen B (continuous regimen) consisted of 6MP (50 mg/m2/day by mouth) plus MTX (20 mg/m2/week by mouth) combined with pulses of PRD and VCR (the same dosages as Regimen A) every 4 weeks. As the late intensification therapy (LIT), five courses of high-dose MTX (2000 mg/m2 per dose per week intravenously for three doses every 12 weeks) with leucovorin rescue were administered to all patients who were in continuous complete remission (CCR) for more than 2 years. Sixty and 55 patients, respectively, were registered in Regimen A and B. The CCR rates in Regimen A and B were 75.1% +/- 5.8% (mean +/- 1 SE) and 49.7% +/- 7.3% (P less than 0.01) at 4 years, and 72.1% +/- 6.3% and 49.7% +/- 7.3% (P less than 0.05) at 5 years, respectively. In Regimen B, CNS and testicular relapses increased after 3 years of CCR. In addition, the patients in Regimen B had a much higher incidence of infections than Regimen A. The LIT did not seem to have important effects on the duration of CCR. From these data we conclude that the intermittent cyclic regimen of 6MP and MTX may be more effective as compared to the continuous administration of these drugs in the maintenance chemotherapy.

The occurrence of marker cells in fetal hematopoiesis of beige (Chédiak-Higashi) mouse

The presence of neutrophils and their precursors with peroxidase-positive and sudanophilic giant granules, which are characteristic of Chédiak-Higashi syndrome (CHS), in the fetal liver and blood of beige (CH), but not of the control C 57 Black, mice was observed. This finding supports the view that the prenatal diagnosis could be possible, if the fetal blood specimen is obtainable safely, assuming the occurrence of similar marker cells in fetal hematopoiesis in CHS of human.