Magnetic Resonance Imaging Assessment of Subchondral Bone and Soft Tissues in Knee Osteoarthritis

Knee osteoarthritis (OA) has to be considered a whole joint disease. Magnetic resonance imaging (MRI) allows superior assessment of all joint tissues that may be involved in OA, such as the subchondral bone, synovium, ligaments, and periarticular soft tissues. Reliable MRI-based scoring systems are available to assess and quantify these structures and associated pathology. Cross-sectional and longitudinal evaluation has enabled practitioners to understand their relevance in explaining pain and structural progression.

Cryptic SYT/SXX1 fusion gene in high-grade biphasic synovial sarcoma with unique complex rearrangement and extensive BCL2 overexpression

Synovial sarcomas are high-grade malignant mesenchymal tumors that account for 10% of all soft-tissue sarcomas. Almost 95% of these tumors are characterized by a nonrandom chromosomal abnormality, t(X;18)(p11.2;q11.2), that is observed in both biphasic and monophasic variants. In this article, we present the case of a 57-year-old woman diagnosed with high-grade biphasic synovial sarcoma in which conventional cytogenetic analysis revealed the constant presence of a unique t(18;22)(q12;q13), in addition to trisomy 8. The rearrangement was confirmed by fluorescence in situ hybridization. The use of the whole chromosome painting probes WCPX did not detect any rearrangements involving chromosome X, although reverse-transcriptase polymerase chain reaction (PCR) analysis demonstrated the conspicuous presence of a SYT/SXX1 fusion gene. Spectral karyotyping (SKY) was also performed and revealed an insertion of material from chromosome 18 into one of the X chromosomes at position Xp11.2. Thus, the karyotype was subsequently interpreted as 47,X,der(X)ins(X;18) (p11.2;q11.2q11.2),der(18)del(18)(q11.2q11.2)t(18;22)(q12;q13),der(22)t(18;22). Real-time PCR analysis of BCL2 expression in the tumor sample showed a 433-fold increase. This rare finding exemplifies that thorough molecular-cytogenetic analyses are required to elucidate complex and/or cryptic tumor-specific translocations. (C) 2010 Elsevier Inc. All rights reserved.

Protease activity and the ultrastructure of broiler chicken PSE (pale, soft, exudative) meat

The biological cause of broiler PSE meat seems to be an excessive release of Ca(2+), promoted by a genetic mutation of ryanodine receptors located in the sarcoplasmic reticulum of skeletal muscle cells. Excessive Ca(2+), associated with protein denaturation in meat, enhances protease activity and influences the functional properties of PSE meat. Twenty-four-hour post-mortem Pectoralis major m. samples exhibited lower values for pH, water-holding capacity, and shear force than did control samples, in contrast to colour (L*) and cooking loss values. Protease activity, measured as myofibril fragmentation index, presented higher values in PSE meat than in control samples. Ultrastructural examination revealed shrinking and depolymerisation of myofilaments and Z-lines disorganisation within the sarcomere in PSE meat. Intense calpain activity was also observed, indicating that the process may initiate at the filaments, because of protein denaturation, and spread through Z-lines, resulting in the collapse of the sarcomere structure. (C) 2009 Elsevier Ltd. All rights reserved.

Effect of supplementation of soft drinks with green tea extract on their erosive potential against dentine

Background: Matrix metalloproteinase (MMP) inhibitors reduce dentine erosion. This in vitro study evaluated the effect of the supplementation of soft drinks with green tea extract, a natural inhibitor of MMPs, on their erosive potential against dentine. Methods: For each drink tested (Coca-Cola (TM), Kuat (TM) guarana, Sprite (TM) and light Coca-Cola (TM)), 40 dentine specimens were divided into two subgroups differing with respect to supplementation with green tea extract at 1.2% (OM24 (R), 100% Camellia sinensis leaf extract, containing 30 +/- 3% of catechin; Omnimedica, Switzerland) or not (control). Specimens were subjected to four pH cycles, alternating de-and remineralization in one day. For each cycle, samples were immersed in pure or supplemented drink (10 minutes, 30 mL per block) and in artificial saliva (60 minutes, 30 mL per block) at 37 degrees C, under agitation. Dentine alterations were determined by profilometry (mu m). Data were analysed by two-way ANOVA and Bonferroni`s test (p < 0.05). Results: A significant difference was observed among the drinks tested with Sprite (TM) leading to the highest surface loss and light Coca-Cola (TM) to the lowest. Supplementation with green tea extract reduced the surface loss by 15% to 40% but the difference was significant for Coca-Cola (TM) only. Conclusions: Supplementation of soft drinks with green tea extract might be a viable alternative to reduce their erosive potential against dentine.

Effect of ion supplementation of a commercial soft drink on tooth enamel erosion

Acidic soft drinks are potentially erosive for dental hard tissues. This in vitro study evaluated the effect of calcium, fluoride, iron and phosphate, supplemented alone or in combination to a commercial citric acid-based carbonated beverage on dental erosion. Ninety enamel samples (4 x 4 x 3 mm) were randomly allocated to nine groups (n = 10): G1 - pure beverage (control); G2 - with 1 mM Ca; G3 - with 0.047 mM F; G4 - with 1 mM Fe; G5 - with 1 mM P; G6 - with 1 mM Ca and 0.047 mM F; G7 - with 1 mM Ca and 1 mM P; G8 - with 1 mM Fe and 0.047 mM F; and G9 - with 1 mM Ca, 1 mM P, 0.047 mM F and 1.0 mM Fe. The samples were subjected to six pH cycles over a 24-h period. In each cycle, the samples were immersed in pure or modified beverage (1 min) and in artificial saliva (59 min). During the remaining period (18 h), the samples were maintained in artificial saliva. Enamel loss was assessed by profilometry (mm). Data were tested using ANOVA and Tukey`s tests (p < 0.05). Highest enamel losses were observed in the control group (G1) and in the groups containing Fe (G4 and G8). The groups containing Ca (G2 and G6) showed significantly less wear compared to control. In conclusion, the modification of an erosive soft drink with low concentrations of Ca with or without F may reduced its erosive potential.

Effect of 4% titanium tetrafluoride solution on dental erosion by a soft drink: An in situ/ex vivo study

Objective: This in situ/ex vivo study assessed the effect of titanium tetrafluoride (TiF4) on permanent human enamel subjected to erosion. Design: Ten volunteers took part in this study performed in two phases. In the first phase (ERO), they wore acrylic palatal appliances containing two enamel blocks, divided into two rows: TiF4 (F) and no-TiF4 (no-F). During the 1st day, the formation of a salivary pellicle was allowed. In the 2nd day, the TiF4 solution was applied on one row (ERO + F), whereas on the other row no treatment was performed (ERO + no-F). From 3rd until 7th day, the blocks were subjected to erosion, 4x per day. In the 2nd phase (no-ERO), the volunteers wore acrylic palatal appliances containing one enamel block, during 2 days, to assess the effect of TiF4 only (no-ERO + F). Enamel alterations were determined using profilometry (wear), microhardness (%SMHC) tests, scanning electron microscope and microprobe analysis. The %SMHC and wear were tested using ANOVA and Tukey`s post hoc tests (p < 0.05). Results: The mean of %SMHC and wear ( mu m) values ( +/- S.D.) were, respectively: ERO + F -73.32 +/- 5.16(A)/2.40 +/- 0.60(a); ERO + no-F -83.49 +/- 4.59B/1.17 +/- 0.48(b) and no-ERO + F -67.92 +/- 6.16(A)/0.21:E 0.09(c). In microscope analysis, the no-F group showed enamel with honeycomb appearance. For F groups, it was observed a surface coating with microcracks. The microprobe analysis revealed the presence of the following elements (%) in groups ERO + F, ERO + no-F and no-ERO + F, respectively: Ca (69.9, 72.5, 66.25); P (25.9, 26.5, 26.06); Ti (3.0, 0, 5.93). Conclusions: The TiF4 was unable to reduce dental erosion. (c) 2007 Elsevier Ltd. All rights reserved.

Heat Release, Time Required, and Cleaning Ability of Mtwo R and ProTaper Universal Retreatment Systems in the Removal of Filling Material

Introduction: This ex vivo study evaluated the heat release, time required, and cleaning efficacy of MTwo (VDW, Munich, Germany) and ProTaper Universal Retreatment systems (Dentsply/Maillefer, Ballaigues, Switzerland) and hand instrumentation in the removal of filling material. Methods: Sixty single-rooted human teeth with a single straight canal were obturated with gutta-percha and zinc oxide and eugenol-based cement and randomly allocated to 3 groups (n = 20). After 30-day storage at 37 degrees C and 100% humidity, the root fillings were removed using ProTaper UR, MTwo R, or hand files. Heat release, time required, and cleaning efficacy data were analyzed statistically (analysis of variance and the Tukey test, alpha = 0.05). Results: None of the techniques removed the root fillings completely. Filling material removal with ProTaper UR was faster but caused more heat release. Mtwo R produced less heat release than the other techniques but was the least efficient in removing gutta-percha/sealer. Conclusions: ProTaper UR and MTwo R caused the greatest and lowest temperature increase on root surface, respectively; regardless of the type of instrument, more heat was released in the cervical third. Pro Taper UR needed less time to remove fillings than MTwo R. All techniques left filling debris in the root canals. (I Endod 2010;36:1870-1873)

Effect of Conventional and Resin-modified Glass-Ionomer Liner on Dentin Adhesive Interface of Class I Cavity Walls After Thermocycling

Objective: The aim of this in vitro study was to analyze the effect of glass-ionomer cement as a liner on the dentin/resin adhesive interface of lateral walls of occlusal restorations after thermocycling. Materials and Methods: Occlusal cavities were prepared in 60 human molars, divided into six groups: no liner (1 and 4); glass-ionomer cement (GIC, Ketac Molar Easymix, 3M ESPE) (2 and 5); and resin-modified glass-ionomer cement (RMGIC, Vitrebond, 3M ESPE) (3 and 6). Resin composite (Filtek Z250, 3M ESPE) was placed after application of an adhesive system (Adper Single Bond 2, 3M ESPE) that was mixed with a fluorescent reagent (Rhodamine B) to allow confocal microscopy analysis. Specimens of groups 4, 5 and 6 were thermocycled (5 degrees C-55 degrees C) with a dwell time of 30 seconds for 5000 cycles. After this period, teeth were sectioned in approximately 0.8-mm slices. One slice of each tooth was randomly selected for confocal microscopy analysis. The other slices were sectioned into 0.8 nun x 0.8 mm beams, which were submitted to microtensile testing (MPa). Data were analyzed using two-way ANOVA and Tukey test (p < 0.05). Results: There was no detectedstatistical difference on bond strength among groups (alpha < 0.05). Confocal microscopy analysis showed a higher mean gap size in group 4(12.5 mu m) and a higher percentage of marginal gaps in the thermocycled groups. The RNIGIC liner groups showed the lowest percentage of marginal gaps. Conclusions: Lining with RMGIC resulted in less gap formation at the dentin/resin adhesive interface after artificial aging. RMGIC or GIC liners did not alter the microtensile bond strength of adhesive system/resin composite to dentin on the lateral walls of Class I restorations.

Tooth abnormalities and soft tissue alterations in patients with G/BBB syndrome

OBJECTIVE: The G/BBB syndrome is an X-linked recessive disorder characterized by eye anomalies, laryngotracheoesophageal cleft, congenital heart disease, genitourinary anomalies and gastrointestinal disorders. Patients may also present cleft lip and palate, high-arched palate and thin upper lip. This study aimed to investigate the occurrence of tooth abnormalities and soft tissue changes in patients with G/BBB syndrome. DESIGN: Cross-sectional. SUBJECTS AND METHODS: Twenty-one patients with G/BBB syndrome were analyzed as to the presence of tooth abnormalities and soft tissue alterations. MAIN OUTCOME MEASURES: The prevalence of tooth agenesis and supernumerary teeth was compared to patients without morphofunctional alterations, matched for gender and age. RESULTS: All patients had complete cleft lip and palate; 95.23% of patients presented tooth abnormalities, mainly hypoplastic alterations, with predominance of alterations of number, followed by alterations of structure, shape and position. The frequency of tooth agenesis and supernumerary teeth was significantly higher compared with the control group; 11 patients presented incisiform supernumerary teeth in the mandibular anterior region. Ankyloglossia was observed in 11 of 21 patients. CONCLUSION: The presence of mandibular anterior supernumerary teeth and ankyloglossia should be investigated in the clinical evaluation of patients with suspected diagnosis of the G/BBB syndrome. Oral Diseases (2008) 14, 747-753

Tooth abnormalities and soft tissue changes in patients with velocardiofacial syndrome

Objective. The objective of this study was to investigate the prevalence of tooth abnormalities and soft tissue changes in patients with velocardiofacial syndrome. Study design. Twenty-six patients with velocardiofacial syndrome were examined to investigate the presence of tooth abnormalities and soft tissue alterations. The occurrence of tooth agenesis and supernumerary teeth was compared to patients without morphofunctional alterations, matched for gender and age. Results. Of all patients, 76.92% exhibited at least one tooth abnormality, with predominance of hypoplastic alterations, especially represented by hypodevelopment of the lingual cusp of mandibular first premolars and enamel opacities. The occurrence of tooth agenesis and supernumerary teeth was similar in both study and control groups. Conclusion. the present results suggest an association between hypodevelopment of the lingual cusp of mandibular first premolars and enamel opacities, yet these findings still require corroboration. Future studies should further investigate these aspects in larger samples compared to control groups, as well as employing molecular genetics techniques.

Influence of interimplant distances and placement depth on peri-implant bone remodeling of adjacent and immediately loaded Morse cone connection implants: a histomorphometric study in dogs

Objectives The aim of this study was to histomorphometrically evaluate the influence of interimplant distances (ID) and implant placement depth on bone remodeling around contiguous Morse cone connection implants with `platform-shifting` in a dog model. Material and methods Bilateral mandibular premolars of six dogs were extracted, and after 12 weeks, each dog received 8 implants, four placed 1.5 mm subcrestally (SCL) on one side of the mandible and four placed equicrestally (ECL) on the other side, alternating the ID of 2 and 3 mm. The experimental groups were SCL with IDs of 2 mm (2 SCL) and 3 mm (3 SCL) and ECL with IDs of 2 mm (2 ECL) and 3 mm (3 ECL). Metallic crowns were immediately installed. After 8 weeks, the animals were euthanized and histomorphometric analyses were performed to compare bone remodeling in the groups. Results The SCL groups` indices of crestal bone resorption were significantly lower than those of ECL groups. In addition, the vertical bone resorption around the implants was also numerically inferior in the SCL groups, but without statistical significance. No differences were obtained between the different IDs. All the groups presented similar good levels of bone-to-implant contact and histological bone density. Conclusion The subcrestal placement of contiguous Morse cone connection implants with `platform shifting` was more efficient in preserving the interimplant crestal bone. The IDs of 2 and 3 mm did not affect the bone remodeling significantly under the present conditions. To cite this article:Barros RRM, Novaes AB Jr., Muglia VA, Iezzi G, Piattelli A. Influence of interimplant distances and placement depth on peri-implant bone remodeling of adjacent and immediately loaded Morse cone connection implants: a histomorphometric study in dogs.Clin. Oral Impl. Res. 21, 2010; 371-378.doi: 10.1111/j.1600-0501.2009.01860.x.