Analysis of Polymorphisms in the Lactotransferrin Gene Promoter and Dental Caries

Regarding host aspects, there has been strong evidence for a genetic component in the etiology of caries. The salivary protein lactotransferrin (LTF) exhibits antibacterial activity, but there is no study investigating the association of polymorphisms in the promoter region of LTF gene with caries. The objective of this study was firstly to search the promoter region of the human LTF gene for variations and, if existent, to investigate the association of the identified polymorphisms with dental caries in 12-year-old students. From 687 unrelated, 12-year-old, both sex students, 50 individuals were selected and divided into two groups of extreme phenotypes according to caries experience: 25 students without (DMFT = 0) and 25 with caries experience (DMFT ≥ 4). The selection of individuals with extreme phenotypes augments the chances to find gene variations which could be associated with such phenotypes. LTF gene-putative promoter region (+39 to −1143) of the selected 50 individuals was analyzed by high-resolution melting technique. Fifteen students, 8 without (DMFT = 0) and 7 with caries experience (mean DMFT = 6.28), presented deviations of the pattern curve suggestive of gene variations and were sequenced. However, no polymorphisms were identified in the putative promoter region of the LTF gene

Proteomic Expression Profile in Human Temporomandibular Joint Dysfunction

Temporomandibular joint dysfunction (TMD) is a multifactorial condition that impairs human’s health and quality of life. Its etiology is still a challenge due to its complex development and the great number of different conditions it comprises. One of the most common forms of TMD is anterior disc displacement without reduction (DDWoR) and other TMDs with distinct origins are condylar hyperplasia (CH) and mandibular dislocation (MD). Thus, the aim of this study is to identify the protein expression profile of synovial fluid and the temporomandibular joint disc of patients diagnosed with DDWoR, CH and MD. Synovial fluid and a fraction of the temporomandibular joint disc were collected from nine patients diagnosed with DDWoR (n = 3), CH (n = 4) and MD (n = 2). Samples were subjected to label-free nLC-MS/MS for proteomic data extraction, and then bioinformatics analysis were conducted for protein identification and functional annotation. The three TMD conditions showed different protein expression profiles, and novel proteins were identified in both synovial fluid and disc sample. TMD is a complex condition and the identification of the proteins expressed in the three different types of TMD may contribute to a better comprehension of how each pathology develops and evolutes, benefitting the patient with a focus–target treatment

Multilevel modeling for dental caries among adolescents in a Brazilian large city

Dental caries is a complex disease, which needs an approach that considers caries influencing factors at different levels and their integration. Multilevel Modeling is a clustered analysis of variables from the individual to the community level. The aim of this study was to investigate the association of social and biological factors grouped into hierarchical levels, in students with caries. A sample of 687 students was evaluated from public and private schools of Curitiba. The parameters evaluated were: individual level, school level and district level. Individual variables had a highly significant association with caries experience, also in the presence of school and district levels. Male sex negatively associated with caries experience. However, the interaction between male sex and no fluoride use was positively associated with caries. Lower socioeconomic status, dental biofilm, and fluorosis were associated with caries. Nevertheless, the interaction between dental biofilm and fluorosis was negatively associated with caries experience. The interaction between no flossing and use of public dental services were also associated with caries outcome. Individual factors were associated with caries experience even with the inclusion of contextual variables in the study population