RESUMEN
The objective of this study was to determine the normal values of faciolingual thickness (FLT) of the papilla base, papilla height (PH), and gingival angle (GA) among Chinese adults and the association of FLT with the gingival phenotype. The periodontal phenotypes of 105 volunteers were confirmed by Kan et al's periodontal probe transmission method and classification. All volunteers received complete supragingival scaling and were recalled after 1 week for clinical examination and for recording various periodontal indices, including Plaque Index, Gingival Index, and periodontal depth. The FLT, PH, and GA of maxillary anterior teeth were measured, and their associations were analyzed. The mean FLT of papilla between the right canine (CA) and lateral incisor (LI) was 8.11 ± 0.64 mm; between the right LI and central incisor (CI) was 7.77 ± 0.64 mm; between the right CI and left CI was 8.49 ± 0.66 mm; between the left CI and LI was 7.62 ± 0.63 mm; and between the left LI and CA was 8.17 ± 0.63 mm. The thin-phenotype group showed a greater PH and FLT than the thick phenotype group. Inversely, the GA of the thick-phenotype group was greater than the corresponding values for the thin-phenotype group. In Chinese residents, the high and thick papilla are associated with the thin phenotype, while the low and thin papilla are associated with the thick phenotype. The GA is negatively correlated with PH. A weak correlation exists between the GA and FLT of papilla.
Asunto(s)
Encía , Maxilar , Adulto , China , Humanos , Incisivo , FenotipoRESUMEN
Objective:To evaluate the impact of sample pooling strategy on 2019-nCoV RNA detection results.Methods:Ten negative swabs were stored in 6 ml virus transport medium, mixed thoroughly and diluted 1∶2 and 1∶10. Inactivated 2019-nCoV culture medium was added to simulate pooling samples: 10 pooling samples, 5 pooling samples and 1 swab sample. Extraction and amplification were made using three nucleic acid extraction reagents a, b, and c with different extraction methods and systems, as well as five 2019-nCoV detection reagents A-E with various template loading volumes and sensitivities respectively.Results:For the same sample, the Ct values of extracted templates a were 2.10±0.47 and 3.46±0.62 earlier than extracted templates b and c. For samples with identical amplifying, the Ct valves of N and ORF1ab gene of A reagent were 1.16±0.48 and 2.36±0.54 earlier than that of reagent B. Adding nucleic acid of 10 negative swabs to the amplification system lagged the Ct values of reagent A by about 1.36±0.32 Ct, while Ct values of reagent B were not affected. Extracted by regent a, a lag of 1.66±0.39 Ct on average was observed in C, D, and E reagents in detecting pooling samples of ten swabs as compared with one swab sample. When extracting 400 copies/ml pooling samples of ten swabs by reagent a, N gene could be detected by reagents C and E, but not by reagent D.Conclusion:Large amount of extraneous DNA is introduced by sample pooling, which could interfere the effiency of extraction and amplification. Strategies of using extraction reagents with large loading volume and high effiency, together with amplification reagents with large template volume and low limit of detection are helpful for ensuring detection sensitivity of pooling samples, and greatly reducing the risk of false negative results.
RESUMEN
From a sample of 108 periodontally healthy volunteers with different combinations of morphometric data related to maxillary central anterior teeth and the surrounding soft tissues, this article aims to categorize gingival phenotypes according to tooth and gingival parameters, as well as assess the relationships between tooth shape and gingival characteristics, such as the papillary height (PH) and faciolingual thickness (FLT) of the papilla base. The periodontal phenotypes of 108 volunteers were confirmed using the periodontal probe transmission method for Kan classification. The FLT, PH, and the crown width to crown length (CW/CL) ratio for maxillary anterior teeth were measured. K-clustering was used to classify the anterior tooth shape into three groups: triangular, square, and compound. The mean CW/CL ratio for the maxillary anterior tooth position of the thick phenotype was greater than that of the thin phenotype. The PH and FLT for the maxillary anterior interdental papillae were greater for the thin phenotype group than for the thick phenotype group. A negative correlation was observed between the CW/CL ratio and both PH and FLT (P < .05 for both). However, a significant positive correlation was observed between FLT and PH. CW/CL ratio, FLT, and PH were all associated with the gingival phenotype with significant statistical correlations (P < .05 for all). Triangular teeth were correlated with scallop-shaped gingiva in the faciolingual area, while square teeth were associated with a flat gingiva.