Targeting phosphatidylinositol-3-kinase for inhibiting maxillary bone resorption.

Previous studies have suggested a role of phosphatidylinositol-3-kinase gamma (PI3Kγ) in bone remodeling, but the mechanism remains undefined. Here, we explored the contribution of PI3Kγ in the resorption of maxillary bone and dental roots using models of orthodontic tooth movement (OTM), orthodontic-induced inflammatory root resorption, and rapid maxillary expansion (RME). PI3Kγ-deficient mice (PI3Kγ-/- ), mice with loss of PI3Kγ kinase activity (PI3KγKD/KD ) and C57BL/6 mice treated with a PI3Kγ inhibitor (AS605240) and respective controls were used. The maxillary bones of PI3Kγ-/- , PI3KγKD/KD , and C57BL/6 mice treated with AS605240 showed an improvement of bone quality compared to their controls, resulting in reduction of the OTM and RME in all experimental groups. PI3Kγ-/- mice exhibited increased root volume and decreased odontoclasts counts. Consistently, the pharmacological blockade or genetic deletion of PI3K resulted in increased numbers of osteoblasts and reduction in osteoclasts during OTM. There was an augmented expression of Runt-related transcription factor 2 (Runx2) and alkaline phosphatase (Alp), a reduction of interleukin-6 (Il-6), as well as a lack of responsiveness of receptor activator of nuclear factor kappa-Β (Rank) in PI3Kγ-/- and PI3KγKD/KD mice compared to control mice. The maxillary bones of PI3Kγ-/- animals showed reduced p-Akt expression. In vitro, bone marrow cells treated with AS605240 and cells from PI3Kγ-/- mice exhibited significant augment of osteoblast mineralization and less osteoclast differentiation. The PI3Kγ/Akt axis is pivotal for bone remodeling by providing negative and positive signals for the differentiation of osteoclasts and osteoblasts, respectively.

Burden of dental caries in individuals experiencing food insecurity: a systematic review and meta-analysis.

CONTEXT: Food insecurity affects approximately 2.37 billion people worldwide. Individuals experiencing food insecurity are more likely to exhibit poor health-related endpoints. Dental caries, a highly prevalent noncommunicable disease, is modulated by an interplay between biological, behavioral, and environmental factors. OBJECTIVE: This systematic review and meta-analysis aimed to assess whether individuals experiencing food insecurity were more likely to exhibit dental caries than individuals facing food security. DATA SOURCES: The Web of Science, PubMed, Scopus, Embase, Ovid, CINAHL, LILACS, and APA PsycINFO databases were checked from inception to November 2021. Grey literature and Google Scholar were also examined. An updated search was conducted in August 2022. Observational studies were included if they evaluated the association between dental caries and food insecurity status. DATA EXTRACTION: Data extraction was performed by two reviewers. DATA ANALYSIS: Random-effects meta-analyses were conducted using R language. In total, 514 references were retrieved from databases, of which 14 articles were included in qualitative synthesis and 7 were merged into meta-analysis. The results of an inverse-variance meta-analysis (OR = 1.62; 95%CI, 1.01-2.60) and a meta-analysis of binary data (OR = 1.66; 95%CI, 1.36-2.02) demonstrated that food-insecure individuals were more likely to exhibit dental caries than food-secure individuals. Inverse-variance meta-analyses appraising multiple strata of food security also showed that individuals experiencing marginal food security (OR = 1.48; 95%CI, 1.28-1.72), individuals experiencing low food security (OR = 1.26; 95%CI, 1.01-1.57), and those experiencing very low food security (OR = 1.33; 95%CI, 1.04-1.71) were more likely to exhibit dental caries than individuals experiencing full food security. CONCLUSION: Dental caries is associated with food insecurity. Individuals living with food insecurity are more likely to exhibit dental caries than those who have food security. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration number CRD42021268582.

Longitudinal assessment of the impact of orthodontic treatment on adolescents' quality of life: a comparison between boys and girls using a condition specific questionnaire.

The aim of this study was to compare the impact of the first year of wearing of a fixed orthodontic appliance on the Oral Health-Related Quality of Life (OHRQoL) between boys and girls, by means of a condition-specific instrument. The study included 69 adolescents aged 10 to 18 years, who were undergoing orthodontic treatment with a fixed appliance. Of the 69 adolescents, 38 were girls (55.1%) and 31 were boys (44.9%). They answered the Brazilian version of the Impact of Fixed Appliance Measure (B-IFAM) questionnaire three months (T1) and one year (T2) after the fixed appliance was installed. This questionnaire contains 43 questions, distributed across nine domains. The higher the scores, the more negative the perception of the adolescent concerning the impact of the fixed appliance on his/her OHRQoL. Sociodemographic and clinical variables were also analyzed, and statistical analysis was performed. For the domains, the effect size (the magnitude of the difference between girls and boys) and the minimal clinically important difference were also calculated. The adjusted regression showed that there was a significantly greater increase in the overall B-IFAM score in girls than in boys, indicating a more negative perception of the OHRQoL over the study time [Coefficient=11.77 (3.47- 20.60), p=0.006]. From T1 to T2, there was a significantly greater increase in the scores (more negative perception of OHRQoL over time) in girls than in boys for the domains aesthetics (p=0.034) and physical impact (p=0.011). These differences were clinically significant. The effect size (the magnitude of the difference) was moderate. The impact of wearing a fixed appliance on the OHRQoL was more negative in girls than in boys during the first year of orthodontic treatment.

O objetivo deste estudo foi comparar o impacto do primeiro ano de uso do aparelho fixo na qualidade de vida relacionada a saúde bucal (QVRSB) entre meninas e meninos, através de um instrumento condição específica. Sessenta e nove adolescentes entre 10 e 18 anos, em tratamento ortodôntico com aparelho fixo foram incluídos. Adolescentes responderam ao questionário Impact of fixed appliance measure (B-IFAM) no terceiro mês de uso do aparelho fixo (T1) e um ano após a colagem do aparelho fixo (T2). Este questionário possui 43 perguntas, distribuídas em nove domínios. Quanto maior os escores, mais negativa a percepção do adolescente com relação ao impacto do aparelho fixo na QVRSB. Variáveis sociodemográficas e clínicas também foram avaliadas. Análise estatística foi realizada. Para os domínios, tamanho de efeito (a magnitude da diferença entre meninas e meninos) e diferença mínima clinicamente importante também foram calculadas. Dos 69 adolescentes, 38 eram meninas (55,1%) e 31 eram meninos (44,9%). Na regressão ajustada, meninas apresentaram um aumento significativamente maior do escore total do B-IFAM do que meninos, indicando uma percepção mais negativa da QVRSB ao longo do tempo de acompanhamento [Coeficiente=11,77 (3,47­20,60), p=0.006]. Meninas apresentavam um aumento significativamente maior dos escores de T1 para T2 (percepção mais negativa da QVRSB ao longo do tempo) em relação aos meninos para os domínios estética (p=0,034) e impacto físico (p=0,011). Estas diferenças também foram clinicamente significativas. O tamanho do efeito (a magnitude da diferença) foi moderado. Meninas demonstraram um impacto mais negativo do uso do aparelho fixo na QVRSB do que meninos nos 12 primeiros meses de tratamento ortodôntico.

Photobiomodulation Enhances Cisplatin Cytotoxicity in a Culture Model with Oral Cell Lineages.

Cisplatin plays a central role in cancer chemotherapy, but resistance to this drug remains a major obstacle in treatment. Drawbacks related to cisplatin failure may be associated with cell energy metabolism. This study investigated whether photobiomodulation (PBM) can potentiate the effects of cisplatin on keratinocytes (HaCat) and cancer cells (SCC25 and HN12). Cells were treated with laser (GaAlAs; 660 nm; 60 mW; 0.33 J; 2.14 W cm-2 ; 11.7 J cm-2 and 6 s) and cisplatin (7.8 µg mL-1 ) to evaluate cell viability, Ki-67, VEGF, TGF-ß1, EGF expression and ROS production. Observations were validated in the SCC25 cell lineage, where the type of cell death (necrosis/apoptosis) and the amount of ATP were assessed. Cell lineages showed increased sensitivity to cisplatin associated with PBM (Cis-PBM). Ki-67 was augmented in all cell lineages treated with Cis-PBM when compared to cisplatin alone (Cis). Cis or Cis-PBM significantly decreased VEGF expression in cancer cells, while no changes were seen in the expression of TGF-ß1 or EGF compared to control. ROS levels were similar in the Cis and Cis-PBM groups. Cells treated with Cis-PBM died by apoptosis, leading to greater consumption of ATP. These observations suggest that PBM may potentiate the effects of cisplatin, leading to increased drug cytotoxicity and enhanced cell death.

Calcifying epithelial odontogenic tumours: Collaborative study of 32 cases and review of literature.

OBJECTIVES: To analyse the occurrence of calcifying epithelial odontogenic tumours (CEOT) based on biopsy records from different Brazilian geographic regions and to contrast the data with a review of the literature. MATERIALS AND METHODS: A 2-step study was conducted. Step 1 consisted of a collaborative study of biopsies obtained from 1953 to 2017 at six Brazilian oral and maxillofacial pathology centres. Evaluation of 86,268 biopsy records was performed. Demographic and histopathological diagnosis data were assessed. In Step 2, a review of the literature of case reports and cases series of CEOT identified across five electronic databases was conducted. RESULTS: In the collaborative study, 32 cases of CEOT were evaluated. This figure represented 0.03% of the oral and maxillofacial lesions and 1.7% of all odontogenic tumours across the centres. Women in the fourth decade of life were more affected. CEOT occurred more in the mandible than in the maxilla (ratio 1.9:1). The review of the literature showed that Asian individuals were more affected by this neoplasm. CONCLUSIONS: Useful knowledge on the epidemiology, treatment and follow-up of CEOT has been provided. Demographic data and clinical features of the cases presented in this collaborative study were quite similar to those of studies reported worldwide.

A multicentre study of 268 cases of calcifying odontogenic cysts and a literature review.

OBJECTIVES: To investigate the frequency of calcifying odontogenic cysts (COCs) that have been submitted for microscopic examination from representative geographic regions of Brazil and to compare it with literature data. MATERIALS AND METHODS: A retrospective study was conducted on biopsies obtained from 1953 to 2016 at 10 Brazilian oral and maxillofacial pathology centres. A total of 198,350 biopsy specimens were analysed. Demographic data and histopathological diagnosis were evaluated descriptively and statistically. In addition, a literature review of case series was carried out in four electronic databases. RESULTS: A total of 268 cases of COC were surveyed, representing 0.1% of the oral lesions at the centres studied. Female patients in their second decade of life and the maxilla were more affected. The mean lesion size of symptomatic individuals was larger than that of cases without symptoms (p = 0.026). The literature review showed a higher frequency in Asia and Europe, mainly affecting men in the third decade of life. CONCLUSIONS: COC is a rare lesion. Novel data on the clinicopathological features of 268 cases have been added to the literature. Data regarding gender and age of the Brazilian patients reported herein contrast with findings of case series and retrospective studies reported elsewhere.