Performance of multiple therapeutic approaches for palatal wound healing after soft tissue graft removal - an overview of systematic reviews.

OBJECTIVE: To overview the literature to answer the following question: "What is the performance of different therapies on wound healing and postoperative discomfort after palatal ASTG removal?" METHODS: SRs that evaluated the wound healing (WH), postoperative pain, bleeding, and analgesic consumption of patients submitted to de-epithelialized/free gingival grafts (FGG) or subepithelial connective tissue grafts (SCTG) removed from the palate were included. The searches were conducted on six white and two gray databases up to December 2023. Methodological quality was evaluated through AMSTAR 2. The synthesis of results was described as a narrative analysis. RESULTS: Ten SRs (involving 25 randomized clinical trials) related to low-level laser therapy (LLLT) (3), platelet-rich fibrin (PRF) (4), cyanoacrylate tissue adhesives (CTA) (2), and ozone therapy (OT) (1) were included in this overview. All techniques demonstrated improvements in WH. LLT, PRF, and CTA reduced pain and analgesic consumption. PRF and CTA reduced bleeding. Regarding methodological quality, the SRs were classified as critically low (2), low (5), moderate (2), or high quality (1). CONCLUSIONS: In SRs related to LLLT, PRF, CTA, and OT, the use of different therapies after palatal ASTG removal improved WH and postoperative discomfort. Due to the studies' low methodological quality and high heterogeneity, data should be interpreted with caution. CLINICAL RELEVANCE: The present overview compiles the evidence of SRs related to different therapies for WH and patients' postoperative experience and reveals that different treatments can significantly improve the clinical outcomes of patients who require ASTG removal for periodontal or peri-implant surgeries. REGISTRATION: PROSPERO registration number: CRD42022301257.

Evaluation of the biological activities of Copaiba (Copaifera spp): a comprehensive review based on scientometric analysis.

Copaíba oil-resin is extracted from the trunk of the Copaíba tree and has medicinal, cosmetic, and industrial properties. As a result, widespread knowledge about the use of Copaíba oil-resin has evolved, attracting the scientific community's attention. This paper aims to map the global knowledge production regarding the biological activities of Copaíba (Copaifera spp.). Bibliometric methodological instruments were used to conduct a search of the Web of Science-Core Collection database. The search resulted in 822 references. After screening titles and abstracts, 581 references did not meet the eligibility criteria, leaving 246 references for full-text examination. Subsequently, 15 studies were excluded, resulting in a final set of 232 records for the bibliometric analysis. In vitro was the most published study type, mainly from Brazil, from 2010 to 2020. Regarding the authors, Bastos, JK, and Ambrosio, SR were the ones with the most significant number of papers included. The most frequent keywords were Copaíba oil, Copaíba, and Copaifera. Our findings revealed global study trends about Copaíba, mainly related to its various effects and use over time. In general, all countries have conducted more research on antimicrobial and anti-inflammatory activities, also exposing its antioxidant and healing properties. Copaifera reticulata was the most investigated, followed by Copaifera langsdorffi and Copaifera multijuga in both in vitro and in vivo studies. Therefore, there is a need for human reports, given the promising results that Copaíba oils have been demonstrating.

Perfil de componentes curriculares e docentes de Odontologia Legal e saúde coletiva de cursos de graduação em Odontologia da região norte do Brasil / Profile of curricular components and professors of Forensic Dentistry and Public Health in undergraduate dentistry courses in the northern region of Brazil

Introdução: Odontologia Legal (OL) e Saúde Coletiva (SC) contribuem na formação do cirurgião-dentista em aspectos relacionados à ética profissional, à cidadania e à atenção às necessidades de saúde da população. Objetivo: analisar o perfil de componentes curriculares e docentes de OL e SC de cursos de graduação em Odontologia. Material e método: Trata-se de um estudo transversal quantitativo desenvolvido por meio de formulário eletrônico aplicado a docentes de componentes curriculares de OL e SC de cursos da região norte do Brasil, em 2022. Para análise de dados, foi aplicada estatística descritiva e os testes Qui-quadrado e Exato de Fisher. Resultados: Quarenta docentes participaram da pesquisa, sendo 12 de instituições públicas, 27 de particulares e 1 de ambas. Deles, 10 (25%) eram de OL, 22 (55%) de SC e 8 (23%) de ambos os componentes curriculares. Todos (100%) os componentes curriculares de OL eram obrigatórios e ministrados em 1 a 3 semestres do curso, a maioria com ensino presencial (94,4%) e 50% em aulas teóricas e práticas. Os componentes curriculares de SC possuíam grande variabilidade de distribuição de períodos no curso, a maioria com carga horária de até 200 horas. Pouco mais de 40% dos docentes de OL possuíam formação específica na área. Para SC, 63% dos docentes possuíam formação específica. A oportunidade de trabalho ou de inserção em uma instituição de ensino foi o motivo mais citado pelos docentes que não possuíam formação específica na área dos componentes curriculares que ministravam. Não houve diferença estatisticamente significativa no perfil dos docentes. Conclusão: os componentes curriculares de OL não estavam alinhados às diretrizes da Associação Brasileira de Ética e Odontologia Legal e os componentes curriculares de SC seguiam as previsões das Diretrizes Nacionais Curriculares de 2002

Introduction: Forensic Dentistry (FD) and Public Health (PH) contribute to dentist's development in aspects related to professional ethics, citizenship and attention to the population health needs. Aim: to analyze the profile of FD and PH curricular components and professors in undergraduate courses of Dentistry. Material and methods: a quantitative cross-sectional study was carried out using an electronic questionnaire sent to professors who taught FD and PH in north Brazilian colleges in 2022. To data analysis, descriptive statistics, Chi-square and Fisher's exact tests were applied. Results: Forty professors participated in the survey, 12 from public institutions, 27 from private institutions and 1 from both. Of them, 10 (25%) were professors of FD, 22 (55%) of PH and 8 (23%) of both curricular components. All (100%) FD curricular components were mandatory and taught in 1 to 3 semesters of the course, most with face-to-face teaching (94.4%) and 50% with theoretical and practical classes. PH curricular components had great variability in the distribution of periods in the course, most with a workload up to 200 hours. Just over 40% of FD professors had specific training in the area. In the PH area, 63% of professors had specific training. The opportunity for work or insertion in an educational institution was the reason most cited by professors who did not have specific training in the area of the curricular components they taught. There was no statistically significant difference in the professors' profile. Conclusion: the FD curricular components were not aligned with the guidelines of the Brazilian Association of Ethics and Forensic Dentistry and the PH curricular components followed the predictions of the 2002 National Curricular Guidelines

BMP-2 and asporin expression regulate 5-aza-dC-mediated osteoblast/cementoblast differentiation of periodontal dental ligament mesenchymal progenitor cells.

Periodontal dental ligament (PDL) is composed of heterogeneous population of mesenchymal progenitor cells. The mechanisms that regulate the differentiation of these cells towards osteoblast/cementoblast phenotype are not fully understood. Some studies have demonstrated that is possible to change the pattern of cell differentiation via epigenetic mechanisms. The proposal of this study was to investigate whether 5-aza-2'-deoxycytidine (5-aza-dC) treatment would stimulate the osteoblast/cementoblast differentiation of periodontal ligament mesenchymal progenitor cells (PDL-CD105+ enriched cells), characterized as low osteoblast potential, through bone morphogenetic protein-2 (BMP-2) modulation. PDL-CD105+ cells from a single donor were cloned and characterized in two populations as high osteoblast/cementoblast potential (HOP) and low osteoblast/cementoblast potential (LOP) by mineralization in vitro and expression of osteogenic gene markers, such as runt-related transcription factor 2 (RUNX2), alkaline phosphatase (ALP), osteocalcin (OCN), bone morphogenetic protein 2 (BMP-2) and asporin (ASPN). Next, two LOP clones (L1 and L2) were pretreated with 5-aza-dC (10 µM) for 48 h, cultured under osteogenic condition and evaluated for mineralized matrix in vitro, transcription modulation of osteogenic gene markers, methylated and hydroxymethylated DNA levels of BMP-2 and ASPN and intracellular/extracellular expression of BMP-2 protein. LOP clones showed high expression of ASPN transcripts associated with low mRNA levels of BMP-2, RUNX2, ALP, and OCN. 5-aza-dC treatment raised hydroxymethylated DNA levels of BMP-2 and increased the expression of BMP-2 transcripts in both LOP clones. However, BMP-2 protein (intracellular and secreted forms) was detected only in L1 cell clones, in which it was observed an increased expression of osteoblast/cementoblast markers (RUNX2, ALP, OCN) associated with higher mineralization in vitro. In L2 cell clones, 5-aza-dC increased gene expression of ASPN, with no great change in for osteoblast/cementoblast differentiation potential. These data show that 5-aza-dC improves osteoblast/cementoblast differentiation of PDL-CD105+ cells via BMP-2 secretion, and this effect depends on low levels of ASPN expression.

Is There Any Association Between Chronic Periodontitis and Anxiety in Adults? A Systematic Review.

Periodontitis is a multifactorial disease triggered by dysbiotic biofilms, involving the host's immune response, systemic and behavioral factors, including psychosocial conditions. This systematic review aimed to investigate the possible association between periodontitis and anxiety in adults. Searches were performed in PubMed, Scopus, Web of Science, Lilacs, Cochrane, and OpenGrey databases, without language restrictions, considering studies in adults (P-Participants), with (E-Exposure) and without periodontitis (C- Comparison) in an outcome of association with anxiety (O-outcome). Methodological quality assessment was carried out using the Newcastle-Ottawa protocol for case-control and cross-sectional studies, followed by an analysis of the level of evidence using the GRADE tool. Metanalysis was not performed due to several differences in methods applied by authors in primary studies. Eleven observational studies were selected according to the inclusion criteria from the total of 6,380 studies retrieved from databases. Eight studies demonstrated higher anxiety levels in subjects with periodontitis, among which only one study presented a high risk of bias. The GRADE tool revealed a low level of evidence for the anxiety outcome measured by the State-Trait Anxiety Inventory (STAI), both for case-control and cross-sectional studies. However, since anxiety may affect the quality of life of many subjects, it reinforces the need for further studies that evaluate this association for more extended periods. Clinical Trial Registration:PROSPERO-CRD42020190445.

Transcriptome profile of highly osteoblastic/cementoblastic periodontal ligament cell clones.

BACKGROUND: Heterogeneous cell populations of osteo/cementoblastic (O/C) or fibroblastic phenotypes constitute the periodontal dental ligament (PDL). A better understanding of these PDL cell subpopulations is essential to propose regenerative approaches based on a sound biological rationale. OBJECTIVE: Our study aimed to clarify the differential transcriptome profile of PDL cells poised to differentiate into the O/C cell lineage. METHODOLOGY: To characterize periodontal-derived cells with distinct differentiation capacities, single-cell-derived clones were isolated from adult human PDL progenitor cells and their potential to differentiate into osteo/cementoblastic (O/C) phenotype (C-O clones) or fibroblastic phenotype (C-F clones) was assessed in vitro. The transcriptome profile of the clonal cell lines in standard medium cultivation was evaluated using next-generation sequencing technology (RNA-seq). Over 230 differentially expressed genes (DEG) were identified, in which C-O clones showed a higher number of upregulated genes (193) and 42 downregulated genes. RESULTS: The upregulated genes were associated with the Cadherin and Wnt signaling pathways as well as annotated biological processes, including "anatomical structure development" and "cell adhesion." Both transcriptome and RT-qPCR showed up-regulation of WNT2, WNT16, and WIF1 in C-O clones. CONCLUSIONS: This comprehensive transcriptomic assessment of human PDL progenitor cells revealed that expression of transcripts related to the biological process "anatomical structure development," Cadherin signaling, and Wnt signaling can identify PDL cells with a higher potential to commit to the O/C phenotype. A better understanding of these pathways and their function in O/C differentiation will help to improve protocols for periodontal regenerative therapies.

Association Between Diabetic Retinopathy and Periodontitis-A Systematic Review.

Background: Diabetic retinopathy is a common microvascular complication in diabetic patients and is considered the main cause of visual loss worldwide. Periodontitis is a chronic inflammatory condition, which compromises dental supporting tissues. The chronic bacterial challenge in periodontitis is a persistent source of inflammatory mediators that may be associated with insulin resistance, increasing the risk of complications of diabetes mellitus. This systematic review aimed to summarize the evidence in the association between diabetic retinopathy and periodontitis. Methods: This review was registered under the number CRD 42019142267. A search strategy in five electronic databases and a gray literature source was performed based on the PECO acronym. After data extraction, the qualitative synthesis and risk of bias analyses were performed using the Newcastle-Ottawa scale. The level of evidence of all studies taken together was evaluated through the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. Results: Out of the 253 citations screened, five cross-sectional studies met the eligibility criteria and were included in the qualitative analysis, in which two were judged to be of good quality, one as fair quality, and two as poor quality. Among the included studies, a significant relationship between the severity of periodontitis (CAL > 5 mm) and the severity of diabetic retinopathy (p < 0.05) was reported by four studies. Also, an association between both diseases in non-obese adults was found after adjustments [OR 2.206 (1.114-4.366); p = 0.0232). However, the analysis of evidence by GRADE assessment was rated as low. Conclusions: Although the results of individual studies suggest an association between diabetic retinopathy and periodontitis, the quality of the body of evidence was judged to be low by the GRADE approach. Further studies with larger sample sizes, adequate models of cofounders' adjustments, and prospective analysis of periodontitis and diabetes conditions ought to be conducted to clarify this association.

Transcriptome profile of highly osteoblastic/cementoblastic periodontal ligament cell clones

Abstract Heterogeneous cell populations of osteo/cementoblastic (O/C) or fibroblastic phenotypes constitute the periodontal dental ligament (PDL). A better understanding of these PDL cell subpopulations is essential to propose regenerative approaches based on a sound biological rationale. Objective Our study aimed to clarify the differential transcriptome profile of PDL cells poised to differentiate into the O/C cell lineage. Methodology To characterize periodontal-derived cells with distinct differentiation capacities, single-cell-derived clones were isolated from adult human PDL progenitor cells and their potential to differentiate into osteo/cementoblastic (O/C) phenotype (C-O clones) or fibroblastic phenotype (C-F clones) was assessed in vitro. The transcriptome profile of the clonal cell lines in standard medium cultivation was evaluated using next-generation sequencing technology (RNA-seq). Over 230 differentially expressed genes (DEG) were identified, in which C-O clones showed a higher number of upregulated genes (193) and 42 downregulated genes. Results The upregulated genes were associated with the Cadherin and Wnt signaling pathways as well as annotated biological processes, including "anatomical structure development" and "cell adhesion." Both transcriptome and RT-qPCR showed up-regulation of WNT2, WNT16, and WIF1 in C-O clones. Conclusions This comprehensive transcriptomic assessment of human PDL progenitor cells revealed that expression of transcripts related to the biological process "anatomical structure development," Cadherin signaling, and Wnt signaling can identify PDL cells with a higher potential to commit to the O/C phenotype. A better understanding of these pathways and their function in O/C differentiation will help to improve protocols for periodontal regenerative therapies.

Periodontal ligament-derived mesenchymal stem cells modulate neutrophil responses via paracrine mechanisms.

BACKGROUND: Mesenchymal stem cells differentiate into distinct mesenchymal cell lineages and regulate the immune response. The aim of this study was to determine whether periodontal ligament-derived mesenchymal stem cells (PDLSCs) have the ability to modulate neutrophil responses via paracrine mechanisms. METHODS: CD105-enriched PDLSCs were seeded for 24 h and challenged with Porphyromonas gingivalis total protein extract (PgPE) (0 or 2 ug/mL) for 3 h. Cells were then washed and further cultured for 18 h and the supernatants were collected and stored. Next, neutrophil-differentiated human promyelocytic leukemia HL-60 cells (HL60D) were treated with PDLSCs supernatants and HL-60D activation and functional responses were determined. RESULTS: PgPE treatment induced higher secretion of inflammatory markers and chemokines by PDLSCs, including RANTES, eotaxin, interferon (IFN)-γ- inducible protein 10 (IP-10), monocyte chemoattractant protein-1 (MCP-1), IFN-γ, interleukin (IL)-6, IL-8 and IL-1ra (P < 0.05). HL-60D recruitment rate was increased by 4.7 ± 1.09-fold when exposed to PgPE-treated PDLSCs supernatants. PgPE-treated PDLSCs supernatants promoted a 1.78 ± 1.04-fold increase in the production of intracellular reactive oxygen species (ROS) by PMA-stimulated HL-60D, whereas PgPE-untreated PDLSCs supernatants led to a 16% reduction in intracellular ROS. In sharp contrast, neither PgPE-untreated nor PgPE-treated PDLSCs supernatants altered tumor necrosis factor (TNF)-α and IL-1ß secretion by HL-60D cells. CONCLUSION: Together, these findings suggest an important role of PDLSCs in the recognition of P. gingivalis, paracrine recruitment and activation of antimicrobial mechanisms in innate immune cells, without interfering in cytokine responses.

Periodontitis and Alzheimer's Disease: A Possible Comorbidity between Oral Chronic Inflammatory Condition and Neuroinflammation.

Periodontitis is an oral chronic infection/inflammatory condition, identified as a source of mediators of inflammation into the blood circulation, which may contribute to exacerbate several diseases. There is increasing evidence that inflammation plays a key role in the pathophysiology of Alzheimer's disease (AD). Although inflammation is present in both diseases, the exact mechanisms and crosslinks between periodontitis and AD are poorly understood. Therefore, this article aims to review possible comorbidity between periodontitis and AD. Here, the authors discuss the inflammatory aspects of periodontitis, how this oral condition produces a systemic inflammation and, finally, the contribution of this systemic inflammation for worsening neuroinflammation in the progression of AD.

Novel Nanotechnology of TiO2 Improves Physical-Chemical and Biological Properties of Glass Ionomer Cement.

The aim of this study was to assess the performance of glass ionomer cement (GIC) added with TiO2 nanotubes. TiO2 nanotubes [3%, 5%, and 7% (w/w)] were incorporated into GIC's (Ketac Molar EasyMix™) powder component, whereas unblended powder was used as control. Physical-chemical-biological analysis included energy dispersive spectroscopy (EDS), surface roughness (SR), Knoop hardness (SH), fluoride-releasing analysis, cytotoxicity, cell morphology, and extracellular matrix (ECM) composition. Parametric or nonparametric ANOVA were used for statistical comparisons (α ≤ 0.05). Data analysis revealed that EDS only detected Ti at the 5% and 7% groups and that GIC's physical-chemical properties were significantly improved by the addition of 5% TiO2 as compared to 3% and GIC alone. Furthermore, regardless of TiO2 concentration, no significant effect was found on SR, whereas GIC-containing 7% TiO2 presented decreased SH values. Fluoride release lasted longer for the 5% and 7% TiO2 groups, and cell morphology/spreading and ECM composition were found to be positively affected by TiO2 at 5%. In conclusion, in the current study, nanotechnology incorporated in GIC affected ECM composition and was important for the superior microhardness and fluoride release, suggesting its potential for higher stress-bearing site restorations.

Viability and Osteogenic Differentiation of Human Periodontal Ligament Progenitor Cells Are Maintained After Incubation With Porphyromonas gingivalis Protein Extract.

BACKGROUND: Porphyromonas gingivalis (Pg) is a major periodontal pathogen that contains immunostimulatory components. Periodontal ligament mesenchymal stem cells (PDLMSCs) are responsible for regeneration of the periodontium that is lost due to periodontitis. Pathologic factors within the microenvironment that impair resident PDLMSCs are not well understood. The present study investigates in vitro the effects of Pg protein extract (PgPE) on biologic properties of CD105-enriched PDL progenitor cell populations (PDL-CD105+). METHODS: Five populations of PDL-CD105+ cells were exposed to PgPE and assessed for cell viability, apoptosis, and proinflammatory gene expression (interleukin-1ß [IL-1ß], tumor necrosis factor-alpha [TNF-α], and IL-6) by quantitative reverse transcription polymerase chain reaction, IL-6 immunostaining, activation of IL-6/signal transducer and activator of transcription (STAT) 3 signaling pathway, and osteogenic differentiation potential. RESULTS: PgPE treatment (2 µg/mL) did not affect cell viability or survival but induced a significant increase in IL-1ß, TNF-α, and IL-6 messenger RNA (mRNA) expression and positive staining for IL-6. A total of 29 genes from the IL-6/STAT3 pathway were upregulated on PgPE stimulation. These genes are related to biologic processes involved in the control of cell survival (B-cell lymphoma 2 [BCL2]), cell proliferation (hepatocytehepatocyte growth factor), cytokine-mediated signaling pathway (suppressor of cytokine signaling 3, C-X-C ligand 8 [CXCL8]), and response to stress (CXCL8, mitogen-activated protein kinase 3, BCL2-associated X protein, and BCL2). Additionally, PgPE treatment caused an increase in alkaline phosphatase mRNA expression in PDL-CD105+ cells after 7 days of osteogenic induction, although mineral nodule formation was comparable to the control group. CONCLUSIONS: These results suggest that the inflammatory profile induced by PgPE treatment in PDL-CD105+ cells did not affect cell viability, apoptosis, or osteogenic differentiation, perhaps due to increased expression of genes involved in the control of cell proliferation and protection against cell death.

A Novel Modification of Semilunar Coronally Advanced Flap for the Treatment of Gingival Recession: Case Series.

This article aims to describe a modification of the semilunar coronally advanced flap. A total of 12 systemically and periodontally healthy patients presenting Miller Class I gingival recession were treated with the modified semilunar coronally advanced flap technique described in this article. After 1 year of follow-up, the mean root coverage was 85.4% ± 24.7%. Significant gingival recession reduction, clinical attachment gain, and reduction in dentin sensitivity was observed 1 year after surgery. This novel semilunar coronally advanced flap technique was demonstrated to be effective for root coverage in Miller Class I gingival recessions.

Biomimetic coatings enhance tribocorrosion behavior and cell responses of commercially pure titanium surfaces.

Biofunctionalized surfaces for implants are currently receiving much attention in the health care sector. Our aims were (1) to create bioactive Ti-coatings doped with Ca, P, Si, and Ag produced by microarc oxidation (MAO) to improve the surface properties of biomedical implants, (2) to investigate the TiO2 layer stability under wear and corrosion, and (3) to evaluate human mesenchymal stem cells (hMSCs) responses cultured on the modified surfaces. Tribocorrosion and cell experiments were performed following the MAO treatment. Samples were divided as a function of different Ca/P concentrations and treatment duration. Higher Ca concentration produced larger porous and harder coatings compared to the untreated group (p < 0.001), due to the presence of rutile structure. Free potentials experiments showed lower drops (-0.6 V) and higher coating lifetime during sliding for higher Ca concentration, whereas lower concentrations presented similar drops (-0.8 V) compared to an untreated group wherein the drop occurred immediately after the sliding started. MAO-treated surfaces improved the matrix formation and osteogenic gene expression levels of hMSCs. Higher Ca/P ratios and the addition of Ag nanoparticles into the oxide layer presented better surface properties, tribocorrosive behavior, and cell responses. MAO is a promising technique to enhance the biological, chemical, and mechanical properties of dental implant surfaces.

Analysis of the mental foramen using cone beam computerized tomography / Análise do forame mentual em tomografias computadorizadas de feixe cônico

Introduction: Knowledge of the anatomical structures located in the region between the mental foramina is of critical importance in pre-operative planning. Objective: To evaluate the position of the mental foramen relative to the apices of the teeth and the distance to the edges of the mandible, using cone beam computerized tomography. Material and method: One hundred cone beam computerized tomographs of the mandible were evaluated; the tomographs were taken using a single tomographic device. Each image chosen was evaluated repeatedly from both sides of the mandible, the position of the mental foramen, indicating the region in which the foramen was found and the measures of the mental foramen, the lingual cortex and the mandibular base. Initially, the data were analyzed descriptively. A value of p<0.05 was chosen as the level of significance. Result: Forty-two percent of the mental foramina were located in the apex of the second pre-molar. The lingual margin of the mental foramen was located, on average, 3.1mm from the lingual cortex. The lower margin of the mental foramen was located 7.25 mm above the lower edge of the mandible. Conclusion: The mental foramen was located more frequently at a level of the apices of the second pre-molars, with a distance to the lingual cortex, on average, of 3.1mm and to the base of the mandible, on average, of 7.25 mm.

Introdução: O conhecimento das estruturas anatômicas localizadas na região entre os forames mentuais é de importância crucial nos planejamento pré-operatórios. Objetivo: Avaliar a posição do forame mentual relacionado aos ápices dos dentes, sua distância aos bordos da mandíbula com uso da tomografia computadorizada de feixe cônico. Material e método: Foram avaliadas 100 tomografias computadorizadas de feixe cônico da mandíbula realizada num único aparelho de tomografia. Cada imagem escolhida foi avaliada de forma repetida para ambos os lados da mandíbula, a posição do forame mentual, indicando a região em que o forame se encontrava e as medidas do forame mentual a cortical lingual e base da mandíbula. Os dados foram analisados inicialmente de forma descritiva. Um valor de p<0,05 foi escolhido como o nível de significância. Resultado: 42% dos forames mentuais estavam localizados no ápice do segundo pré-molar. A margem lingual do forame mentual localizou-se em média de 3,1 mm a partir da cortical lingual. A margem inferior do forame mentual foi localizada 7,25 mm acima da borda inferior da mandíbula. Conclusão: O forame mentual localizou-se com maior frequência em nível dos ápices dos segundos pré-molares, com distância à cortical lingual, em média, de 3,1 mm e base da mandíbula, em média, de 7,25 mm.

Tooth-derived stem cells: Update and perspectives.

Tissue engineering is an emerging field of science that focuses on creating suitable conditions for the regeneration of tissues. The basic components for tissue engineering involve an interactive triad of scaffolds, signaling molecules, and cells. In this context, stem cells (SCs) present the characteristics of self-renewal and differentiation capacity, which make them promising candidates for tissue engineering. Although they present some common markers, such as cluster of differentiation (CD)105, CD146 and STRO-1, SCs derived from various tissues have different patterns in relation to proliferation, clonogenicity, and differentiation abilities in vitro and in vivo. Tooth-derived tissues have been proposed as an accessible source to obtain SCs with limited morbidity, and various tooth-derived SCs (TDSCs) have been isolated and characterized, such as dental pulp SCs, SCs from human exfoliated deciduous teeth, periodontal ligament SCs, dental follicle progenitor cells, SCs from apical papilla, and periodontal ligament of deciduous teeth SCs. However, heterogeneity among these populations has been observed, and the best method to select the most appropriate TDSCs for regeneration approaches has not yet been established. The objective of this review is to outline the current knowledge concerning the various types of TDSCs, and discuss the perspectives for their use in regenerative approaches.

Engenharia tecidual em periodontia / Tissue engineering in Periodontics

Nas últimas décadas, muitos procedimentos foram realizados com o objetivo de regenerar o periodonto, como a regeneração tecidual guiada, a utilização de enxertos ósseos e os derivados da matriz do esmalte. No entanto, estudos têm demonstrado que estas terapias apresentam baixa previsibilidade de regenerar o periodonto. A fim de aumentar o potencial e previsibilidade de regeneração, a engenharia tecidual tem sido proposta como uma alternativa para promover as condições necessárias para regenerar os tecidos periodontais. Neste contexto, este trabalho teve como objetivo revisar a literatura acerca dos estudos de engenharia tecidual em Periodontia. A engenharia tecidual se baseia em princípios de biologia celular e engenharia de biomateriais, envolvendo basicamente três elementos-chave: células, moléculas de sinalização e arcabouços. O conjunto de células obtidas a partir do ligamento periodontal, assim como células isoladas com fenótipo de células mesenquimais indiferenciadas (células-tronco), tem sido investigado quanto ao potencial em promover a regeneração. Os efeitos das moléculas sinalizadoras sobre estas células e sobre o processo regenerativo também têm sido avaliados. Além disso, diversos arcabouços têm sido estudados com o objetivo de mimetizar a matriz extracelular, carrear células e liberar tais moléculas sinalizadoras na forma de proteínas recombinantes, a fim de propiciar um microambiente mais favorável à regeneração. Abordagens de engenharia tecidual envolvendo a interação destes três elementos têm demonstrado melhores resultados do que o uso isolado de um deles. Com base nestas abordagens, espera-se o desenvolvimento de técnicas que estimulem a regeneração periodontal, levando a resultados satisfatórios mais previsíveis.

Characterization of highly osteoblast/cementoblast cell clones from a CD105-enriched periodontal ligament progenitor cell population.

BACKGROUND: It is known that periodontal ligament (PDL) harbors a heterogeneous progenitor cell population at different stages of lineage commitment. However, characterization of PDL stem cells committed to osteoblast/cementoblast (O/C) differentiation remains to be elucidated. The present study is carried out to isolate single cell-derived, cluster of differentiation (CD)105-positive PDL clones and to characterize the clones that present high potential to differentiate toward O/C phenotype in vitro. METHODS: Isolation of single cell-derived colonies (clones) from a CD105-enriched PDL progenitor cell population was performed by the ring-cloning technique. Cell clones were evaluated for their O/C differentiation potential, metabolic activity, and expression of STRO-1 protein. Additionally, the clones that showed potential to O/C differentiation were characterized by quantitative reverse-transcription polymerase chain reaction (qRT-PCR) for expression of runt-related transcriptor factor 2 (RUNX2), alkaline phosphatase, CD105, and CD166 during osteogenic induction. RESULTS: Six PDL-CD105(+) clones were obtained, three being highly O/C clones (C-O) and three others that did not have the ability to produce mineralized matrix in vitro (C-F). The C-O group showed lower metabolic activity compared with the C-F group, and both cell groups were positively immunostained for STRO-1. qRT-PCR analysis demonstrated an increased expression of transcripts for RUNX2 and CD166 during the maturation of C-O cells toward O/C phenotype. CONCLUSIONS: These results provide evidence that PDL-CD105(+) purified progenitor cells comprise a heterogeneous cell population that presents a cell subset with high O/C potential and, further, that surface antigen CD166 is modulated during the O/C maturation of this cell subset.

Novel ALPL genetic alteration associated with an odontohypophosphatasia phenotype.

Hypophosphatasia (HPP) is an inherited disorder of mineral metabolism caused by mutations in ALPL, encoding tissue non-specific alkaline phosphatase (TNAP). Here, we report the molecular findings from monozygotic twins, clinically diagnosed with tooth-specific odontohypophosphatasia (odonto-HPP). Sequencing of ALPL identified two genetic alterations in the probands, including a heterozygous missense mutation c.454C>T, leading to change of arginine 152 to cysteine (p.R152C), and a novel heterozygous gene deletion c.1318_1320delAAC, leading to the loss of an asparagine residue at codon 440 (p.N440del). Clinical identification of low serum TNAP activity, dental abnormalities, and pedigree data strongly suggests a genotype-phenotype correlation between p.N440del and odonto-HPP in this family. Computational analysis of the p.N440del protein structure revealed an alteration in the tertiary structure affecting the collagen-binding site (loop 422-452), which could potentially impair the mineralization process. Nevertheless, the probands (compound heterozygous: p.[N440del];[R152C]) feature early-onset and severe odonto-HPP phenotype, whereas the father (p.[N440del];[=]) has only moderate symptoms, suggesting p.R152C may contribute or predispose to a more severe dental phenotype in combination with the deletion. These results assist in defining the genotype-phenotype associations for odonto-HPP, and further identify the collagen-binding site as a region of potential structural importance for TNAP function in the biomineralization.

Abordagem regenerativa combinada de proteínas derivadas da matriz do esmalte e substituto ósseo em defeito infraósseo de paciente com periodontite agressiva / Combined regenerative approach of derivative enamel proteins and bone substitute for treatment of infraosseous defect in aggressive periodontitis. Case report

Devido à rápida progressão da doença periodontal, a presença de defeitos periodontais infraósseos é um achado frequente nos pacientes portadores de periodontite agressiva. O objetivo deste trabalho foi relatar clínica e radiograficamente uma abordagem periodontal regenerativa em paciente com histórico de periodontite agressiva generalizada. A paciente apresentava persistência de bolsa periodontal associada a defeito infraósseo na mesial do dente 46 mesmo após abordagens periodontais não cirúrgicas. O sítio foi tratado por meio de terapia periodontal regenerativa utilizando-se proteínas derivadas da matriz do esmalte (PDME) associadas a substituto ósseo composto de beta-tricálcio-fosfato e hidroxiapatita (β-TCP-HA). Dez meses após a terapia regenerativa, observou-se redução da profundidade de sondagem e preenchimento radiográfico do defeito periodontal. Desta forma, pôde-se concluir que a terapia periodontal regenerativa foi capaz de promover melhoras clínicas, demonstrando que tal procedimento é viável, mesmo em pacientes com histórico de periodontite agressiva generalizada.