Objectives: Tissue breakdown was obtained by placing ligatures around dental implants on the same edentulous dog hemimandible. Evaluation of hard tissue loss progression was performed using intravital fluorochrome labeling, as an alternative to standard light microscopy, on thin sections of non-demineralized hybrid bone-implant specimens. Material and Methods: Intravital fluorochrome labeling was administered by intraperitoneal injection of oxytetracycline and alizarin red S. Sections were cut, stained and evaluated by light microscopy and under the epifluorescent microscope. Bone loss architecture was analyzed under three filters: UV, green and red. Results: Epifluorescence microscopy demonstrated continuous bone activity in the surrounding area of the implants during the healing period. LM confirmed the intense cellular activity in the hard tissues around the implants. Conclusion: Within the limits of the present study, epifluorescence can be seen as a complementary approach to the LM “golden standard”, providing both reliable and sufficient information with regard to bone resorption/apposition kinetics.

This cross-sectional case–control study of post-partum women aimed to estimate whether maternal periodontitis was a predictive contributor to preterm birth and to identify other risk factors associated with preterm birth in our target population. The case group included women who delivered preterm (74 cases) and the control group included women who had a normal term delivery (120 controls). Medical records, a 16-item questionnaire, and a full-mouth periodontal examination were used to collect information about socio-demographic characteristics, general health problems, birth-related information, behavioral factors and periodontal status. Logistic regression analysis was used to estimate the strength of the relationship between predictors and the categorical outcome variable, preterm birth. The bivariate analysis revealed the significant associations between preterm birth and socio-demographic factors (educational level, p = 0.003), antepartum smoking habit (p = 0.001) and birth weight lower than 2500 g (p < 0.001). The multivariate analysis highlighted that the presence of post-partum maternal periodontitis and its severity remained independent risk factors of preterm birth in the presence of antepartum smoking habit and route of delivery [adjusted OR 2.26, 95% CI (1.06; 4.82), respectively, OR 3.46, 95% CI (1.08; 11.15)]. Post-partum maternal periodontal disease and its severity might, in part, be considered as contributor to preterm deliveries before 37 weeks of gestation.

Background: Normal or inflamed gingival tissues are regarded as a source of mesenchymal stem cells (MSCs) abundant and easily accessible through minimally invasive dental procedures. Due to the proximity of dental resin composites to gingival tissues and to the possible local cytotoxic effect of the eluted components, gingiva-derived MSCs could be used to investigate the biocompatibility of dental biomaterials. Purpose: The present research aimed to isolate (MSCs) from inflamed and normal gingiva, to fully characterize them and to observe their behavior in relation with some commercial resin composite materials and one experimental material. Material and methods: Following their isolation, putative MSCs from both gingival sources were grown under the same culture conditions and characterized by immunophenotyping of cell surface antigens by flow-cytometry and transcription factors by immunocytochemical staining. Moreover, sternness gene expression was evaluated by RT-PCR analysis. Multipotent mesenchymal differentiation potential was investigated. Osteogenic and neurogenic differentiated cells were highlighted by immunocytochemical staining, chondrogenic cells by cytochemical staining, and adipocytes by cytochemical staining and spectrophotometry, respectively. Resin composite cytotoxicity was evaluated by cell membrane fluorescent labeling with PKH 26 and MTT assay. The results of PKH labeling were statistically analysed using two-way RM ANOVA with Bonferroni post-tests. For MTT assay, two-way RM ANOVA with Bonferroni post-tests and unpaired t test with Welch's correction were used. Results: A similar expression pattern of surface markers was observed. The cells were positive for CD105, CD73, CD90, CD49e, CD29, CD44 and CD166 and negative for CD45, CD34, CD14, CD79, HLA-DR and CD117 indicating a mesenchymal stem cell phenotype. The qRT-PCR analysis revealed a low gene expression for NOG, BMP4 and Oct3/4 and an increased expression for Nanog in both cells lines. lmmunocytochemical analysis highlighted a more intense protein expression for Nanog, Oct3/4 and Sox-2 in MSCs derived from normal gingiva than from inflamed gingiva. Multipotent differentiation capacity of MSCs isolated from both sources was highlighted. The tested materials had no hazardous effect on MSCs as the two cell lines developed well onto resin composite substrates. Cell counting revealed some significant differences in the number of PKH-labeled MSCs at some experimental moments. Also, some differences in cell viability were recorded indicating better developmental conditions offered by some of the tested biomaterials. Conclusions: The experimental resin composite behaved like the most biocompatible commercial material. Inflamed gingiva-derived MSCs retain their stem cell properties and could be used as a valuable cell line for testing dental biomaterials. (C) 2018 Elsevier GmbH. All rights reserved.

Preclinical tests required for the qualification of a biomaterial, designed for tissue-engineering approaches and regenerative medicine, for human trials are generally directed toward the evaluation of the device in animal models that approach the specific clinical application which the device is to be used. Depending on the knowledge in the field and previous data on product one can choose the appropriate model to screen the potential of the biomaterial. The protocols that are now accepted as standardized screening tests are those specific protocols which have been „validated“ through repeated use by different groups and for which consistent results were generated. Our team planned an ample preclinical research to evaluate the post-extraction healing when ridge preservation was performed using different biomaterials. Because these materials have been already tested and used in clinical practice and many data sustain their biocompatibility, we chose to perfect a canine model because: almost all preclinical studies on ridge preservation have been performed on the dog; the alveolar ridge has a similar shape to that of humans; the healing process of the extraction socket is obviously the same as humans and has already been extensively described; the roots of the experimental teeth can be easily removed. Our team studied the early healing qualitative phenomena and the late-healing qualitative and quantitative (dimensional) modifications of the ridges when different ridge preservation approaches were applied. The presented animal model that we perfected was validated by the publication of the results of our research in prestigious journals.

The purpose of this study was the physicochemical characterization of four commercially available xenogeneic materials recommended for periodontal regeneration. The investigation was performed by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy (FTIR) and thermal analysis. The xenogeneic materials are mixtures of amorphous and crystalline phases based on hydroxyapatite (HAP), with variable degrees of crystallinity and crystallite dimensions. They contain different amounts of water, collagen, and mineral phase based on A- and B-type carbonated HAP, with various hydroxylation degrees. The xenogeneic biomaterials are different regarding both the appearance form (granules, spongy block, and bone paste) and ultrastructure (from trabecular architecture to reticulate structure). The biomaterials characteristics are expected to affect their in vivo performance and to influence the outcome of the periodontal treatment.

Dental biomaterials are designed to restore form and function of the dental tissue, to protect the remaining tissue and to create a bond between the dental surface and the restorative material. Due to their proximity to dental structures and oral mucosa, dental biomaterials must fulfil the requirements of biocompatibility and biological durability. The research in the field is focused on achieving these requirements by developing new highly performant biomaterials. But at present, composite materials still present some drawbacks like the polymerisation shrinkage associated to the curing process that leads to the adhesive interface breakdown and marginal microleakage. Composite materials may release substances into the oral environment during setting and later as a result of material degradation. Different side effects of composite materials and their components have been reported i.e. cytotoxic, teratogenic, carcinogenic, mutagenic or genotoxic. Despite the developments in the field, at present no „ideal“ restorative biomaterial with similar characteristics with the natural teeth and completely biocompatible is available. However, the application of strict clinical protocols may improve the above mentioned shortcomings.

AIMS:To investigate the prevalence of periodontitis in a young population representative for the North-western part of Romania (Transylvania) and to identify possible risk indicators of periodontitis. METHODS:The study is a cross-sectional epidemiological survey. The subjects were students randomly sampled from three universities in Cluj-Napoca and high school students from the neighboring city of Bistrita. The sample size of the population was calculated. Overall, 623 subjects aged 16-35 years were evaluated, of which 488 were university students and 135 high school students. A structured questionnaire was administrated to collect information on socio-behavioral status and oral hygiene habits. Periodontal data was collected using a full-mouth methodology by trained examiners. A recent introduced case definition was used to pick up periodontitis cases. RESULTS:The older the subject, the more frequent toothbrushing, dental visits, and use of interproximal hygiene devices, but also addiction to tobacco and alcohol consumption. The prevalence of periodontitis was 0.96% (n=6). Half of these subjects (n=3, 0.48%) were considered to have aggressive periodontitis (AP). Low frequency of toothbrush changing was identified to influence the development of periodontitis. Smoking and lower socioeconomic level did not seem to correlate with periodontal disease in the present study. CONCLUSIONS:In order to better understand the prevalence of periodontal diseases and identify periodontitis cases as well as to evaluate the impact of specific behavioral factors on the disease development in individual and population levels, further extensive screenings are obviously required. Periodontal prevention programs focusing on oral health behavior are mandatory.

BACKGROUND The aim of this study was to evaluate whether the combination of enamel matrix derivative (EMD) with subepithelial connective tissue graft (SCTG) plus coronally advanced flap (CAF) would improve the treatment outcomes of Miller class I and II gingival recessions when compared with the same technique (SCTG plus CAF) alone. METHODS The study was designed as a randomized, parallel, controlled, double-blinded clinical trial. Forty-two patients were randomly assigned in the test group (SCTG plus EMD) and in the control group (SCTG). Patients had at least one gingival recession ≥ 2 mm. The clinical parameters were evaluated at baseline and at 14 d, 1, 3, 6 and 12 mo follow-up time points. RESULTS Forty-two patients, 21 in the test group (SCTG plus EMD) and 21 in the control group (SCTG), aged 21-48 years (mean age 31 ± 8.56) were initially included in the study. Both treatments, STCG plus EMD and SCTG, resulted in a significant final mean root coverage (2.91 ± 0.95mm and 2.91 ± 1.29 mm, respectively) (p < 0.001) and in a high mean percentage of root coverage (82.25 ± 22.20% and 89.75 ± 17.33%, respectively) (p < 0.001), 1 year after surgery. The differences in mean root coverage recorded for the two techniques after 1 year, were not statistically significant (p = 0.19). Complete root coverage was achieved in 56.5% of patients treated with SCTG plus EMD and in 70.6% of patients treated with SCTG (p = 0.275), 1 year after treatment. CONCLUSIONS The present study failed to demonstrate any additional clinical benefits when EMD was added to SCTG plus CAF.

The composite materials used for dental restorations must have adequate mechanical properties in order to resist to the high masticatory forces to which they are subjected in the oral environment. The knowledge of these properties is important for understanding the clinical behavior of composite materials and for the success of the restorative treatment. The present study investigates the mechanical properties like flexural, compressive and diametral tensile strengths of a Romanian composite resin in comparison with two registered trademark dental biomaterials. The Romanian composite has a mechanical behavior similar with the control materials, being suitable for the oral environment conditions.

The aim of the present study was to investigate the biological effects of two resin-based restorative dental materials placed in direct contact with cells isolated from palatal connective tissue graft (CTG) and to demonstrate that the harvested palatal CTG contained progenitor cells. Palatal cells were isolated from tissues collected from individuals undergoing periodontal surgeries. Composite resin and compomer discs plated with ex vivo expanded cells were used to analyze the cell characteristics by scanning electron microscopy (SEM). The amount of the inorganic filler of the two dental materials was determined by thermogravimetric (TGA) analysis. The composite resin had a relatively smaller amount of inorganic filler and was quite stable above 750 degrees C in comparison with the glass ionomer-resin composite. Resin composite and compomer materials seemed to have no cytotoxic effect on isolated cells since the cells had grown well on both restorative materials. Over the entire cultivation period, the cells remained undifferentiated and did not change the phenotype, which sustained that they are undifferentiated cell types.

This study investigated the water sorption (Wsp) and water solubility (Wsl) of one experimental indirect composite [Barodent/ICCRR] in comparison with two trademark dental materials used for inlay restorations [Gradia/GC, BelleGlass/Kerr], as well as the effect of post-curing treatment of composite resins on these properties. The statistical analysis of data showed significant differences between the investigated materials regarding Wsp and Wsl; no statistical differences were observed between the specimens subjected to post-curing and those that were not post-cured. One may conclude that this process was not influenced by the post-curing treatment.

This study used a quantitative method to assess microleakage at the tooth-restoration interface in relation with the type of indirect resin-based composite used. Forty standardized class II cavities for inlays were prepared in 20 previously extracted, sound permanent third molars. Teeth were randomly divided into 2 groups (n=20) and restored with composite inlays using the Gradia (GC Corporation, Japan) and Barodent composite (Institute for Research in Chemistry, Romania). Composite inlays were prepared by the indirect technique; they were built up on models after cavity impressions according to the manufacturer's instructions. All inlays were luted using self-adhesive dual cured resin cement (G-Cem/GC Corp). Microleakage testing was done by immersing the restored teeth in 2% methylene blue solution for 24 hours. Dye penetration at gingival and occlusal margin, along the tooth-cement interface was evaluated using an inverted microscope (Olympus KC301, Olympus America Inc.) at 40x magnification. Dye penetration values were recorded (pm) using QuickPhoto Micro 2.2 software (Olympus Inc) and data were subjected to statistical analysis. No significant differences regarding microleakage in dentin and enamel were observed between the analysed groups (p<0.05). Significant differences between the enamel and dentin interface was observed within the same group.

The purpose of this study was to evaluate the ability of a new Romanian composite biomaterial to be used for indirect restorations ( inlays). In this purpose, 40 standardized class II cavities were prepared on freshly extracted, sound third molars and restored with composite inlays using the Romanian composite Barodent as well as a well known trademark composite. The restored teeth were sectioned mesio-distally and then analysed. The structure of the inlays and the adhesion to the dental tissues were investigated by using scanning electron microscopy and X-ray dispersive energy analysis. The SEM micrographs showed a rather homogeneous structure of the Romanian composite, as well as its quality of adhesion to the dental hard tissues.

The aim of the study was to determine the prevalence of periodontal disease and the treatment needs in a population of 214 factory workers in Romania. Of those examined, 9.34 per cent were in periodontal health (code 0), 21.49 per cent had gingival bleeding (code 1), 18.69 per cent had supra- or subgingival calculus (code 2), 32.71 per cent presented with pathological pockets 4-5 mm deep (code 3) and 17.76 per cent had pathological pockets 6 mm or deeper (code 4). The distribution of these subjects among the treatment need categories revealed that 30.83 per cent would need improvement in personal oral hygiene (I), 51.40 per cent from the subjects would need treatment (I) + scaling (II) and 17.76 per cent would need treatment (I + II) + complex treatment (III).