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This study investigated the effects of indirect composite polymerization on the postcuring mechanical properties of a fiber-reinforced composite. An indirect composite seated on glass fibers preimpregnated with polymerized monomer was polymerized by 1) photoirradiation using a halogen-fluorescent polymerizing unit for 5 min, 2) method 1 plus secondary heating at 100°C for 15 min, 3) photoirradiation using a metal halide light unit for 60 s, or 4) preliminary polymerization using a halogen light unit for 20 s followed by method 3. After polymerization, the flexural and shear bond strengths of the fiber-reinforced composite were examined, as was the flexural strength of non-fiber-reinforced composite specimens polymerized using the same methods. Among non-fiber-reinforced composite specimens, flexural strength was lower for method 1 than for the other three methods; however, among fiberreinforced composite specimens, the four methods did not significantly differ in flexural strength or shear bond strength. Composite-fiber interface separation without breakage of the fiber after flexural strength testing was not observed in specimens polymerized by methods 2 or 4. In conclusion, use of a conventional unit for high-intensity light irradiation after preliminary irradiation, or light irradiation followed by secondary heating, is recommended for polymerization of composite material seated on polymerized glass fiber. [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa is a low-virulence pathogen that can cause infection in immunocompromised patients. Among pediatric hematologists, it is known that careful attention should be paid to P. aeruginosa as the bacteria responsible for intraoral inflammation, and antibiotic therapy targeting P. aeruginosa is the first-line treatment during neutropenia in patients with hematological malignancy. Immunosuppressed patients, however, are at high risk of developing inflammation. Here, we report a case involving a 10-year-old patient with acute lymphoid leukemia (ALL), in which P. aeruginosa synergistically acted with pre-existing gingivitis to induce unusual oral necrotic lesions, leading to acute buccal cellulitis and pus discharge from external sinus tracts. [ABSTRACT FROM AUTHOR]

A 7-year-old girl with hyperimmunoglobulin E syndrome (HIES) presented to our clinic with tooth agenesis in both primary and permanent dentitions. The patient's serum immunoglobulin E level was elevated at 17,091 IU/ml, and her medical history indicated the occurrence of HIES, numerous skin abscesses, and recurrent infection by bacteria and/or fungi such as Candida from birth. She also suffered from heart disease. Dental manifestations included extensive caries, impaired root resorption of primary mandibular central incisors and absence of primary mandibular canines and permanent mandibular lateral incisors. Intraoral phenotypes in HIES patients have already been reported in detail, but no previous report has described abnormalities in the number of primary teeth in HIES patients. The purpose of this report was to describe the dental manifestations in the primary dentition of a hyperimmunoglobulin E syndrome patient and to emphasize the importance of preventive dental management from early childhood in compromised children, such as those with HIES. [ABSTRACT FROM AUTHOR]

Congenital absence of one or more teeth, hypodontia, is the most common developmental anomaly and is often accompanied by the presence of other tooth anomalies. In this case two Japanese sisters have several congenitally missing primary and permanent teeth and morphological abnormalities of maxillary first molars. One sister has transposition of mesial and distal aspects of a maxillary first molar, whose cusps display a normal shape. Another sister has maxillary first molars, which look like maxillary second molars. Mesio-distally shift of teeth is a very rare anomaly making this particular case important to analyze the teeth formation and development. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to investigate the inhibitory effect of a PRG Barrier Coat on biofilm formation and structure by Streptococcus mutans and propose an effective method for preventing dental caries., Materials and Methods: Streptococcus mutans MT8148 biofilms were obtained from hydroxyapatite disks with and with- out a PRG Barrier Coat. Scanning electron microscopy (SEM) was used to observe the 12- and 24-h-cultured biofilms, while reverse-transcription polymerase chain reaction (qRT-PCR) was used to quantify caries-related genes. Biofilm adhe- sion assessments were performed on glass. Statistical analysis was performed using a two-sample t-test., Results: A statistically significant difference in Streptococcus mutans biofilm adhesion rate was observed between the con- trol and PRG Barrier Coat-coated samples (p < 0.01). However, there was no statistically significant difference in total bacter- ial count or biofilm volume (p > 0.05). SEM revealed that the PRG Barrier Coat inhibited biofilm formation by Streptococcus mutans. Real-time RT-PCR revealed that the material restricted the expression of genes associated with caries-related bio- film formation. However, the suppression of gtfD and dexB differed from that of other genes., Conclusion: PRG Barrier Coat suppressed biofilm formation by Streptococcus mutans by inhibiting the expression of in- soluble glucan synthase, which is associated with primary biofilm formation. The material also affected gene expression and altered the biofilm structure. Tooth surface-coating materials, such as PRG Barrier Coat, may improve caries preven- tion in dental practice.