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Objective: To perform a phenotypic characterization of the dento-osseous anomalies in a Brazilian family with Familial Adenomatous Polyposis (FAP) and to investigate the adenomatous polyposis coli (APC) causative variant., Design: The study included a family of 14 individuals (Group A: affected; Group B: non-affected). The frequency of radiographic findings in both groups was evaluated according to the Dental Panoramic Radiograph Score (DPRS) diagnostic method. The accuracy and reproducibility of DPRS were tested. The DNA was isolated from the index patient's saliva and submitted to whole-exome and Sanger sequencing approach., Results: DPRS ≥ 7 was observed in 80 % of Group A but in none of Group B. The most common findings in Group A were dense bone islands (60 %), hazy sclerosis (40 %), osteomas (40 %), and supernumerary tooth (20 %). DPRS has proved to be a reliable method while DPRS ≥ 5 and DPRS ≥ 7 were taken as positive for FAP, and reproducible diagnosis test considering that the evaluators correctly identified the affected patients (Kappa agreement>0.8, p = 0.002). A nonsense heterozygous mutation in the APC gene (c.1370C > G; p.Ser457*) of the index case was detected., Conclusion: FAP patients have a higher frequency of dento-osseous anomalies (p = 0.005). Bone abnormalities were more prevalent than dental anomalies (p = 0.001). Thus, FAP patients should be referred for dental examination and genetic counseling to perform early diagnosis of dento-osseous anomalies and evaluate the implications of the molecular findings in each particular family., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Objective: The aim of the study was to evaluate the effect of topical fluoride gel NaF 2% application on antioxidant parameters of whole saliva from children., Design: The saliva mechanically stimulated with parafilm was collected from 25 children (6-12 years) attending the Clinic of Paediatric Dentistry of Universidade Cruzeiro do Sul, São Paulo, Brazil, before (control group) and immediately after application of neutral fluoride gel NaF 2% (fluoride-gel group), according to the Standards for Research Using Human Subjects, Resolution 196/96 of the USA National Health Council of 10/10/1996. Afterwards, pre-post ferric-reducing antioxidant power (FRAP), trolox-equivalent antioxidant capacity (TEAC), uric acid, reduced/oxidised glutathione content (GSH/GSSG) and total peroxidase activity (TPO) were evaluated in whole saliva of both groups., Results: All non-enzymatic antioxidant parameters were augmented by fluoride-gel NaF 2% application, whereas a notable reduction (31%) of peroxidase activity was concomitantly observed in the children's saliva (p ≤ 0.05). Nevertheless, the reducing power of saliva was kept unaltered under these circumstances (p ≤ 0.05)., Conclusions: Despite the reduced activity of peroxidase (an important antimicrobial and antioxidant enzyme), the topical fluoride gel NaF 2% favourably stimulated the release of non-enzymatic antioxidant components of saliva, sustaining the reducing power of saliva and the natural defences of the oral cavity., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

There is a relationship between hypocalcaemia and the enamel hypoplasia. Earlier studies in rats have reported a severe hypocalcaemia and enamel hypoplasia a month after thyro-parathyroidectomy (TPTX). The aims of this study were to look at earlier stages and to attempt to correlate morphological changes with alterations in the distribution of amelogenin. Twenty-five Wistar rats were, under anaesthesia, thyro-parathyroidectomized. Sham operated rats were included as controls. After 14, 30 or 57 days, the animals were reanesthatized and the tissues fixed by intracardiac perfusion of fixative. The lower incisors were processed for light microscopy and immunogold electron microscopy. After 14 days the thyro-parathyroidectomised rats were severely hypocalcaemic but amelogenesis was morphologically similar to controls. After 30 and 57 days, enamel defects were observed in the late secretory and early maturation stages in the thyro-parathyroidectomised rats. The immunocytochemical study revealed a concentration of stippled material immunolabelled for amelogenin at the secretory pole of the ameloblasts in the hypocalcaemic rats. The absence of enamel defects after 14 days suggests that this was an insufficient hypocalcaemic period to induce morphological alterations. The concentration of stippled material containing amelogenin suggests that alterations in matrix formation may be the basis of the morphological changes.