Cytotoxicity of dilutions of bioceramic materials in stem cells of human exfoliated deciduous teeth.

OBJECTIVE: Several materials have been developed to preserve pulp vitality. They should have ideal cytocompatibility characteristics to promote the activity of stem cells of human exfoliated deciduous teeth (SHED) and thus heal pulp tissue. OBJECTIVE: To evaluate the cytotoxicity of different dilutions of bioceramic material extracts in SHED. METHODOLOGY: SHED were immersed in αMEM + the material extract according to the following experimental groups: Group 1 (G1) -BBio membrane, Group 2 (G2) - Bio-C Repair, Group 3 (G3) - MTA Repair HP, Group 4 (G4) - TheraCal LC, and Group 5 (G5) - Biodentine. Positive and negative control groups were maintained respectively in αMEM + 10% FBS and Milli-Q Water. The methods to analyze cell viability and proliferation involved MTT and Alamar Blue assays at 24, 48, and 72H after the contact of the SHED with bioceramic extracts at 1:1 and 1:2 dilutions. Data were analyzed by the three-way ANOVA, followed by Tukey's test (p<0.05). RESULTS: At 1:1 dilution, SHED in contact with the MTA HP Repair extract showed statistically higher cell viability than the other experimental groups and the negative control (p<0.05), except for TheraCal LC (p> 0.05). At 1:2 dilution, BBio Membrane and Bio-C showed statistically higher values in intra- and intergroup comparisons (p<0.05). BBio Membrane, Bio-C Repair, and Biodentine extracts at 1:1 dilution showed greater cytotoxicity than 1:2 dilution in all periods (p<0.05). CONCLUSION: MTA HP Repair showed the lowest cytotoxicity even at a 1:1 dilution. At a 1:2 dilution, the SHED in contact with the BBio membrane extract showed high cell viability. Thus, the BBio membrane would be a new non-cytotoxic biomaterial for SHED. Results offer possibilities of biomaterials that can be indicated for use in clinical regenerative procedures of the dentin-pulp complex.

Digital Volumetric Monitoring of Palate Growth in Children With Cleft Lip and Palate.

ABSTRACT: This study aimed to evaluate longitudinally the volume of the dental arches in children with unilateral cleft lip and palate before and after the rehabilitative plastic surgeries. This is a longitudinal retrospective study was composed by 102 digitized dental casts of children with unilateral complete cleft lip (G1) and cleft lip and palate (G2). The palate volume was evaluated at 3 periods: preoperative (T1), postoperative 1 (T2), and postoperative 2 (T3). The intra- and inter-examiner reliability was analyzed by Wilcoxon test/Dahlberg formula and interclass correlation coefficient, respectively. The intragroup comparison was analyzed by Wilcoxon test and Friedman test followed by post-hoc Dunn test. Mann-Whitney test was applied for the intergroup comparison (α = 5%). G1 had a significant growth at T2 (P = 0.031). G2 demonstrated a positive development at T2, but decreased at T3 (P = 0.003). The intergroup analysis revealed that G2 showed a greater volume at T1 and T2 (P < 0.0001 and P = 0.0024, respectively). T2-T1 exhibited no statistically significant difference (P = 0.262). In conclusion, there was a volumetric increase in the dental arches after cheiloplasty followed by a reduction after palatoplasty. Further investigations are necessary to validate the preliminary results of the present study.

Could the photobiomodulation therapy induce angiogenic growth factors expression from dental pulp cells?

This study aimed to evaluate the effect of different photobiomodulation (PBM) radiant exposures on the viability, proliferation, and gene expression of pulp fibroblasts from human primary teeth (HPF) involved in the pulp tissue repair. HPF were irradiated with Laser InGaAlP (Twin Flex Evolution, MMOptics®) at 660-nm wavelength (red); single time, continuous mode, 0.04-cm2 laser tip area, and 0.225-cm laser tip diameter, keeping the distance of 1 mm between the laser beam and the cell culture. The doses used were between 1.2 and 6.2 J/cm2 and were evaluated at the 6 h, 12 h, and 24 h after PBM. MTT and crystal violet assays evaluated the cell viability and proliferation. RT-PCR verified VEGF and FGF-2 mRNA expression. A blinded examiner analyzed the data through two-way ANOVA followed by Tukey test (p < 0.05). The groups with higher powers (10 mW, 15 mW, 20 mW, and 25 mW), shortest application periods (10 s), and radiant exposures between 2.5 and 6.2 J/cm2 exhibited statistically higher viability than that of the groups with small power (5 mW), longer application period (50 s), and radiant exposure of 6.2 J/cm2 (p < 0.05). VEGF and FGF-2 mRNA expression were observed at the three evaluated periods (6 h, 12 h, and 24 h) and the highest expression was in the shortest period (p < 0.05). All radiant exposures maintained HPF viable. The period of 6 h after irradiation showed statistically greater gene expression for both growth factors than other periods. VEGF mRNA had no differences among the dosimetries studied. The best radiant exposures for FGF-2 gene expression were 2.5 J/cm2 and 3.7 J/cm2.

Photobiomodulation effect on angiogenic proteins produced and released by dental pulp cells.

OBJECTIVE: To verify the photobiomodulation effect on angiogenic proteins produced and released by dental human pulpal fibroblasts (HPFs). MATERIAL AND METHODS: HPFs were irradiated with 660-nm low-level laser at fluences of 2.5 J/cm2 and 3.7 J/cm2. The control group was not irradiated. MTT, crystal violet, and ELISA assays respectively verified viability, proliferation, and angiogenic protein (supernatant/lysate) at 6 h, 12 h, and 24 h after photobiomodulation. Capillary-like structure formation assay verified functional role. Two-way ANOVA/Tukey's test and ANOVA/Bonferroni's multiple comparisons test respectively verified cell viability/proliferation and intragroup and intergroup comparisons of protein synthesis (p < 0.05). RESULTS: Irradiated and non-irradiated HPFs showed statistically similar cell viability and proliferation pattern. Intragroup comparisons showed similar patterns of protein synthesis for all groups: VEGF-A, VEGF-C, and vascular endothelial growth factor receptor 1 (VEGFR1) increased significantly in the supernatant, while FGF-2 and VEGF-A increased significantly in the lysate. The lower fluence significantly increased BMP-9 (6 h) in the supernatant and VEGFR1 (6 h and 12 h) and VEGF-D (24 h) in the lysate, while the higher fluence significantly increased BMP-9 (6 h) in the supernatant and VEGFR1 (12 h) in the lysate. Regardless of the time, both fluences statistically downregulated placental growth factor (PLGF) and PDGF secretion. Both fluences statistically decreased VEGF-A secretion (24 h) and PLGF production (6 h). CONCLUSION: Photobiomodulation produced stimulatory effects on angiogenic protein secretion by pulp fibroblasts. In terms of photobiomodulation, over time, both fluences significantly increased the secretion of VEGF-A, VEGF-C, and VEGFR1 and significantly upregulated BMP-9 (6 h) in the supernatant; for capillary-like structure formation, the fluence of 2.5 J/cm2 was better than the fluence of 3.7 J/cm2. CLINICAL RELEVANCE: This study results addressed effective photobiomodulation parameters tailored for pulp angiogenesis.

Angiogenic protein synthesis after photobiomodulation therapy on SHED: a preliminary study.

This study evaluated the viability, proliferation, and protein expression after photobiomodulation (PBM) of stem cell from human exfoliated deciduous teeth (SHED). The groups were the following: G1 (2.5 J/cm2), G2 (3.7 J/cm2), and control (not irradiated). According to the groups, cells were irradiated with InGaAlP diode laser at 660 nm wavelength, continuous mode, and single time application. After 6 h, 12 h, and 24 h from irradiation, the cell viability and proliferation, and the protein expression were analyzed by MTT, crystal violet, and ELISA multiplex assay, respectively. Twenty-four hours after PBM, SHED showed better proliferation. Over time in the supernatant, all groups had an increase at the levels of VEGF-C, VEGF-A, and PLGF. In the lysate, the control and G2 exhibited a decrease of the VEGF-A, PECAM-1, and PLGF expression, while control and G3 decreased VEGF-C, VEGF-A, and PDGF expression. The dosimetries of 2.5 J/cm2 and 3.7 J/cm2 maintained viability, improved proliferation, and synthesis of the angiogenic proteins in the supernatant in the studied periods on SHED.

Diagnóstico diferencial e conduta clínica de um cisto folicular inflamatório mandibular / Differential diagnosis and management of inflammatory follicular cyst in mandibular anterior area

Este artigo descreve a dificuldade em diagnosticar um cisto folicular inflamatório na área anterior da mandíbula em um menino com dentinogênese imperfeita tipo I (DI-1). Um menino de 6 anos de idade, com DI-1, procurou tratamento devido ao comprometimento estético. O exame radiográfico revelou uma lesão periapical envolvendo os dentes decíduos incisivo central e lateral direitos. Esses dentes foram extraídos sem intercorrências. Após três meses, a criança se queixou de dor em um edema de cor azulada na mesma área. O diagnóstico diferencial foi de cisto folicular e a lesão foi acompanhada. Como os sinais e sintomas persistiram, o tratamento de escolha foi a descompressão da lesão, seguido por irrigação abundante e curetagem das paredes da lesão. O acompanhamento clínico e radiográfico, mostrou, após 6 meses, remissão da lesão, reparo ósseo, e erupção ativa dos incisivos permanentes. As características incomuns deste caso, fizeram com que o diagnóstico de cisto folicular inflamatório fosse dificultado.

This article reports the difficulties in diagnosing an inflammatory follicular cyst in the mandibular anterior area of a boy with type 1 dentinogenesis imperfecta (DI-1). A 6-year-old boy, with DI-1, sought treatment due to esthetic complaints. The radiographic examination revealed a periapical lesion involving the right primary central and lateral incisors. These teeth were extracted with no complications. After three months, the boy complained of pain in a blue-black edema in the same area. The differential diagnosis was of follicular cyst and the lesion was followed-up. As the signs and symptoms persisted, the treatment of choice was to decompress the lesion, followed by copious irrigation, and lesion's wall curettage. After six months, the clinical and radiographic follow-up showed lesion remission, bone repair, and active eruption of permanent incisors. The uncommon characteristics of the case make the diagnosis of inflammatory follicular cyst difficult.