Luiz Alexandre Chisini

Restorations in primary teeth: a systematic review on survival and reasons for failures

BACKGROUND Several restorative materials with specific indications are used for filling cavities in primary teeth. AIM To systematically review the literature in order to investigate the longevity of primary teeth restorations and the reasons for failure. DESIGN Electronic databases were screened, and eligible studies were hand-searched to find longitudinal clinical studies evaluating the survival of restorations (class I, class II, and crown) placed with different materials in primary teeth with at least one year of follow-up. RESULTS Thirty-one studies were included, and a high bias risk was observed. Overall, 12,047 restorations were evaluated with 12.5% of failure rate. A high variation on annual failure rate (AFR) was detected (0-29.9%). Composite resin showed the lowest AFRs (1.7-12.9%). Stainless steel crowns (SSC) had the highest success rate (96.1%). Class I restorations and restorations placed using rubber dam presented better AFR. The main reason for failure observed was secondary caries (36.5%). CONCLUSIONS An elevated number of failures were observed due to recurrent caries, highlighting the need for professionals to work with a health-promoting approach. The high variation on failure rate among the materials can be due to childrens behavior during the procedure, which demands short dental appointments and a controlled environment.

Does Cryopreservation Affect the Biological Properties of Stem Cells from Dental Tissues? A Systematic Review

This systematic review evaluated if different cryopreservation protocols could affect biological properties (Cell survival rate (CSR), proliferation, differentiation, maintenance of stem cell markers) of stem cells obtained from dental tissues (DSC) post-thaw. An electronic search was carried out within PubMed and ISI Web Science by using specific keyword. Two independent reviewers read the titles and abstracts of all reports respecting predetermined inclusion/exclusion criteria. Data were extracted considering the biological properties of previously cryopreserved DSCs and previously cryopreserved dental tissues. DSCs cryopreserved as soon as possible after their isolation presents a CSR quite similar to the non-cryopreserved DSC. Dimethyl sulfoxide (DMSO) [10%] showed good results related to cell recovery post-thaw to cryopreserve cells and tissues for periods of up to 2 years. The cryopreservation of DSC in a mechanical freezer (-80°C) allows the recovery of stem cells post-thaw. The facilities producing magnetic field (MF), demand a lower concentration of cryoprotectant, but their use is not dispensable. It is possible to isolate and cryopreserve dental pulp stem cell (DPSC) from healthy and diseased vital teeth. Cryopreservation of dental tissues for late DSC isolation, combined with MF dispensability, could be valuable to reduce costs and improve the logistics to develop teeth banks.

Platelet-Poor Plasma as a Supplement for Fibroblasts Cultured in Platelet-Rich Fibrin

The aim of this study was to evaluate the proliferation and adhesion of mesenchymal cells (3T3/NIH) in Dulbecco’s Modified Eagle Medium(DMEM) supplemented with Platelet-Poor Plasma (PPP) in aPlatelet-Rich Fibrin (PRF) scaffold. Human blood was obtained and processed in a centrifuge considering the equation G=1.12xRx(RPM/1000)2 to obtain PRF and PPP.Cell adhesion and maintenance analyses were performed by MTTassays in a 96 well plate withsupplemented DMEM: PPP (90:10) for 24 hours. Besides, the PRF was deposited in a 48 well plate and 10x104 cells were seeded above each PRF (n=3) with 800µl of DMEM: PPP (90:10) and cultured for 7 days. Histological analysis and the immunohistochemical staining for Vimentin were performed. Results were analyzed by one-way ANOVA in Stata12®. A significant decrease (p<0.05) of cells adhesion in relationship to FBSwas observed. However, a similar ability of cell-maintenance for PPP 10% was observed (P>0.05). Fibroblasts culture for 7 days in PRF supplemented with PPP 10% was possible, showing positive staining for Vimentin. Therefore, PPP cell supplementation decreased the initial adhesion of cells but was able to maintain the proliferation of adhered cells and able to support their viability in PRF.It seems that this method has many clinical advantagessince it provides an autologous and natural scaffold with their respective supplement for cell culture by only one process, without using xenogeneic compounds. This could improve the potential of clinical translational therapies based on the use of PRF cultured cells, promoting the regenerative potential for future use in medicine and dentistry.

Electrochemical Cathodic Polarization, a Simplified Method That Can Modified and Increase the Biological Activity of Titanium Surfaces: A Systematic Review.

Background The cathodic polarization seems to be an electrochemical method capable of modifying and coat biomolecules on titanium surfaces, improving the surface activity and promoting better biological responses. Objective The aim of the systematic review is to assess the scientific literature to evaluate the cellular response produced by treatment of titanium surfaces by applying the cathodic polarization technique. Data, Sources, and Selection The literature search was performed in several databases including PubMed, Web of Science, Scopus, Science Direct, Scielo and EBSCO Host, until June 2016, with no limits used. Eligibility criteria were used and quality assessment was performed following slightly modified ARRIVE and SYRCLE guidelines for cellular studies and animal research. Results Thirteen studies accomplished the inclusion criteria and were considered in the review. The quality of reporting studies in animal models was low and for the in vitro studies it was high. The in vitro and in vivo results reported that the use of cathodic polarization promoted hydride surfaces, effective deposition, and adhesion of the coated biomolecules. In the experimental groups that used the electrochemical method, cellular viability, proliferation, adhesion, differentiation, or bone growth were better or comparable with the control groups. Conclusions The use of the cathodic polarization method to modify titanium surfaces seems to be an interesting method that could produce active layers and consequently enhance cellular response, in vitro and in vivo animal model studies.

Immunohistochemical Expression of TGF-β1 and Osteonectin in engineered and Ca(OH)2-repaired human pulp tissues

The aim of the present study was to evaluate the expression of transforming growth factor-β1 (TGF-β1) and osteonectin (ON) in pulp-like tissues developed by tissue engineering and to compare it with the expression of these proteins in pulps treated with Ca(OH)2 therapy. Tooth slices were obtained from non-carious human third molars under sterile procedures. The residual periodontal and pulp soft tissues were removed. Empty pulp spaces of the tooth slice were filled with sodium chloride particles (250-425 µm). PLLA solubilized in 5% chloroform was applied over the salt particles. The tooth slice/scaffold (TS/S) set was stored overnight and then rinsed thoroughly to wash out the salt. Scaffolds were previously sterilized with ethanol (100-70°) and washed with phosphate-buffered saline (PBS). TS/S was treated with 10% EDTA and seeded with dental pulp stem cells (DPSC). Then, TS/S was implanted into the dorsum of immunodeficient mice for 28 days. Human third molars previously treated with Ca(OH)2 for 90 days were also evaluated. Samples were prepared and submitted to histological and immunohistochemical (with anti-TGF-β1, 1:100 and anti-ON, 1:350) analyses. After 28 days, TS/S showed morphological characteristics similar to those observed in dental pulp treated with Ca(OH)2. Ca(OH)2-treated pulps showed the usual repaired pulp characteristics. In TS/S, newly formed tissues and pre-dentin was colored, which elucidated the expression of TGF-β1 and ON. Immunohistochemistry staining of Ca(OH)2-treated pulps showed the same expression patterns. The extracellular matrix displayed a fibrillar pattern under both conditions. Regenerative events in the pulp seem to follow a similar pattern of TGF-β1 and ON expression as the repair processes.

Produção especializada no SUS em capitais brasileiras com centros de especialidades odontológicas: uma análise descritiva

Dental Specialty Centers (Centros de Especialidades Odontológicas – CEOs) are specialized health facilities that should perform a minimum number of procedures. Objectives: this study aimed to describe the specialized dental production and report the achievement of goals in Brazilian capitals with CEOs. Materials and method: a retrospective longitudinal study was performed with a search for the CEOs listed in the National Registry of Health Establishments. The dental production was searched in the Outpatient Information System of the Brazilian Unified Health System for the period from May 2015 to April 2016. Results: fifty-nine CEOs were found and considered eligible for the present study. They were located in 19 Brazilian capitals and in the Federal District, whereas 48% were CEOs Type II. Approximately 730 thousand specialized procedures were performed during the 12 months evaluated. A rate of 86% of goals was met and surgery presented the highest achievement (92%), followed by periodontics (89%) and endodontics (76%). One of the capitals achieved only 33% of the goals. Three capitals did not achieve any of the goals set for endodontic procedures. Conclusion: there was a great variation in the achievement of goals among capitals with CEOs. While some capitals showed high achievement of goals, others presented concerning data, especially for endodontic procedures.

Does the skin color of patients influence the treatment decision-making of dentists? A randomized questionnaire-based study

ObjectiveTo investigate whether patients’ skin color could exert an influence on the dentist’s decision-making for treatment, in four different cities in Brazil.Material and methodsLists of dentists were obtained and the sample selection was performed systematically. Two questionnaires were produced for the same clinical case, but the images were digitally manipulated to obtain a patient with a black and a white skin color. Dentists were free to choose treatment without any restrictions, including the financial aspects. A random sequence (white or black) was generated which was placed at random in sealed, opaque envelopes. Dentists were questioned about the decision on the treatment of a severely decayed tooth and an ill-adapted amalgam restoration.ResultsA total of 636 dentists agreed to participate in the study. After adjustments (multinomial logistic regression), it was observed that the black patient with a decayed tooth had a 50% lower risk of being referred for prosthetic treatment (p = 0.023) and a 99% higher risk of receiving a composite resin restoration, compared to the white patient (p = 0.027). No differences were observed regarding recommendation for tooth extraction (p = 0.657). In relation to an ill-adapted amalgam, the black patient had less risk of receiving a referral replacement with composite resin (0.09 95%CI [0.01–0.82]) and finishing and polishing (0.11 5%CI [0.01–0.99]) compared with the white patient.ConclusionPatient skin color influenced the dentist’s choice of treatment. In general, black patients receive referrals for cheaper, simpler procedures.Clinical significanceSkin color played an important role in dentists’ treatment decisions. Professionals may contribute unconsciously to the propagation and replication of racial discrimination.

Accuracy of partial protocol to assess prevalence and factors associated with dental caries in schoolchildren between 8-12 years of age

The aim of this study was to test accuracy and reliability of a partial protocol (PP) of oral examination involving the permanent first molars. This cross-sectional study was carried out in two stages. First, a cross-sectional study was performed in a representative sample of 1,211 children using DMFT-index in a full-mouth protocol (FM). A PP was simulated from FM data using only data from the permanent first molars. A second part was performed with 202 children examined by a gold standard examiner (FM) and three dentists using the PP to assess its reliability. Accuracy of PP was assessed by sensitivity/specificity/predictive positive and negative values. Inter-examiner reliability in comparison with gold standard examiner was assessed using weighted kappa. The prevalence of dental caries observed using DMFT index was 32.4% and was 30.2% for PP . The PP presented high sensitivity (93.1%; 95%CI: 91.5-94.5), showing similar magnitude of associations measures for all associated factors investigated. When compared with the gold standard FM examination, all examiners obtained high parameters of sensitivity and specificity (around 90%). Predictive negative values were higher than predictive positive values for the examiners. This study showed that this partial protocol involving the permanent first molars is accurate and reliable as a screening tool to assess dental caries prevalence and associated factors in schoolchildren.