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The aim of this nonrandomized, multicenter controlled clinical trial was to evaluate the impact of leukocyte–platelet-rich fibrin (LPRF) on regenerative endodontic procedures (REPs) of immature permanent teeth in terms of periapical bone healing (PBH) and further root development (RD). Healthy patients between 6–25 years with an inflamed or necrotic immature permanent tooth were included and divided between the test (= REP + LPRF) and control (= REP-LPRF) group depending on their compliance and the clinical setting (university hospital or private practice). After receiving REP ± LPRF, the patients were recalled after 3, 6, 12, 24, and 36 months. At each recall session, the teeth were clinically and radiographically (by means of a periapical radiograph [PR]) evaluated. A cone-beam computed tomographic (CBCT) imaging was taken preoperatively and 2 and 3 years postoperatively. PBH and RD were quantitatively and qualitatively assessed. Twenty-nine teeth with a necrotic pulp were included, from which 23 (9 test and 14 control) were analyzed. Three teeth in the test group had a flare-up reaction in the first year after REP. Except for 2 no shows, all the analyzed teeth survived up to 3 years after REP, and, in case of failure, apexification preserved them. Complete PBH was obtained in 91.3% and 87% of the cases based on PR qualitative and quantitative evaluation, respectively, with no significant difference between the groups with respect to the baseline. The PR quantitative change in RD at the last recall session with respect to the baseline was not significant (all P values >.05) in both groups. The qualitative assessment of the type of REP root healing was nonuniform. In the test group, 55.6% of the teeth presented no RD and no apical closure. Only 50% of the 14 teeth assessed with CBCT imaging presented complete PBH. Regarding volumetric measurements on RD 3 years after REP for the change with respect to the baseline in root hard tissue volume, mean root hard tissue thickness, and apical area, the control group performed significantly in favor of RD than the test group (P =.03,.003, and 0.05 respectively). For the volumetric change 3 years after REP with respect to the baseline in root length and maximum root hard tissue thickness, no significant difference (P =.72 and.4, respectively) was found between the groups. The correlation between the PR and CBCT variables assessing RD was weak (root lengthening) to very weak (root thickening). REP-LPRF seems to be a viable treatment option to obtain PBH and aid further RD of necrotic immature permanent teeth. Caution is needed when evaluating REP with PR. [ABSTRACT FROM AUTHOR]

Implant-based prosthetic solutions can be time consuming. If implants can be placed successfully with a guide, surgery time can be reduced. The purpose of this randomized controlled clinical trial was to assess implant outcomes, both clinical and radiological, comparing guided with nonguided implant placement after 3 years of follow-up. A total of 314 implants were placed in 72 jaws (60 participants). The jaws were randomly assigned to 1 of the 6 treatment groups: Materialise Universal/mucosa (Mat Mu), Materialise Universal/bone (Mat Bo), Facilitate/mucosa (Fac Mu), Facilitate/bone (Fac Bo), freehand navigation (Freehand), and a pilot-drill template (Templ). Radiographic and clinical parameters (bone loss, pocket probing depth, bleeding on probing, and plaque scores) were recorded at the time of implant placement, prosthesis installment (baseline), and 1-year, 2-year, and 3-year follow-up. Analysis was performed using a linear mixed model, and correction for simultaneous hypothesis was made according to Sidak (α=.05). Three participants left the study before the 3-year follow-up; hence, 302 implants in 69 jaws were included in this study. None of the implants failed. The mean marginal bone loss after the third year of loading was 0.7 ±1.3 mm for the guided surgery group and 0.5 ±0.6 mm for the control group. No significant intergroup or follow-up period differences were observed (P >.05). In the guided surgery groups, the mean number of surfaces with bleeding on probing and plaque at 3-year follow-up was 1.7 ±1.5 and 1.7 ±1.7, respectively; for the control groups, this was 1.6 ±1.4 and 1.6 ±1.6, respectively. The mean pocket probing depth was 3.0 ±1.3 mm for the guided group and 2.6 ±1.0 mm for the control group. No significant differences were found (P >.1). Within the limitation of this study, no statistically significant differences could be found between the guided group and the control group at the 3-year follow-up. [ABSTRACT FROM AUTHOR]

Introduction: Bacterial plaque is an etiologic factor in the development of gingival inflammation and periodontitis. The presence of orthodontic bands and brackets influences plaque growth and maturation. The purposes of this research were to monitor microbiologic and periodontal changes after placement of orthodontic attachments over a 1-year period and to link these changes to alterations in cytokine concentrations in the gingival crevicular fluid (GCF). Methods: This longitudinal split-mouth trial included 24 patients. Supragingival and subgingival plaque composition, probing depth, bleeding on probing, and GCF flow and composition were assessed at baseline (Tb) and after 1 year (T52). A statistical comparison was made over time and between the banded and bonded sites. Prognostic factors for the clinical reaction at T52 in the GCF at Tb were determined. Results: Between Tb and T52, the pathogenicity of the plaque and all periodontal parameters increased significantly, but intersite differences were not seen, except for bleeding on probing. The cytokine concentrations in the GCF did not differ significantly between the sites or between Tb and T52. The interleukin-6 concentration in the GCF at Tb was a significant predictive value for the GCF flow at T52 (P <0.05). The same relationship was found between the interleukin-8 concentration at Tb and the increase in probing depth at T52 (P <0.05). Conclusions: Interleukin-6 and interleukin-8 concentrations before orthodontic treatment were shown to be significant predictive factors for some potential inflammatory parameters during treatment. [Copyright &y& Elsevier]

Objective Secondary caries (SC) is one of the most important reasons for the failure of composite restorations, and thus has wide-reaching implications for the longevity of affected teeth and the health expenditure. Yet, it is currently not known whether secondary caries with composites is a material-based problem. The objective was to review literature with regard to SC around composite restorations to obtain better insights in the mechanisms behind SC with composites. Methods Using Pubmed and Medline, international literature was searched for all articles about the clinical diagnosis, incidence and prevalence, histopathology and factors involved in the onset and development of SC around composite restorations. Additional studies were included after checking the reference lists of included papers. Results SC with composites is to some extent associated to the restorative material, as significantly more caries occurred with composites than with amalgam. On the other hand, the class of the composite restoration (class V versus others and class I versus class II) was also determining for the development of SC, suggesting also other influencing factors than the material itself. The mechanisms behind the development of SC are much less clear and are most probably multifactorial. Even though the role of gaps an microleakage is questioned by some researchers, there are also indications that interfacial failure may play a role. Interfacial gaps larger than 60 μm seem to predispose interfacial demineralization, and may thus lead to caries. The question is therefore whether such interfacial gaps occur clinically? Initially, a gap may originate through polymerization shrinkage and through failure to obtain a good bond. Higher incidences of SC are observed in practice-based than in university-based studies, which may be attributed to different caries risk profiles of the included patients, or to the technique-sensitive placement procedure of composites. More research is necessary to investigate whether large gaps may arise through degradation processes. Apart from these factors, composites also seem to favor the growth of cariogenic bacteria on their surface, which has been associated with specific surface properties, release of components and lack of antibacterial properties. Significance Current literature suggests that the restorative material might influence the development of secondary caries in different ways. However, it should be emphasized that patient-related factors remain the most important determinant of secondary caries. [ABSTRACT FROM AUTHOR]

Morphea is an inflammatory disorder of the skin and underlying tissues characterized by an overabundance of collagen leading to fibrosis. The prevalence of this disease is estimated at around 0.4-2.7/100,000 people. When the process occurs in the gingival tissues, it induces traction, which can cause gingival recession. A 19-year-old woman was referred to the clinic for a progressive recession on teeth 11 and 12. A pale, atrophic, linear region extending from her nose to her upper lip on the right-hand side of her face was diagnosed as morphea en coup de sabre. Cone beam computed tomography, quantitative polymerase chain reaction and histologic evaluation were used to assess the pathology. Treatment with methotrexate was conducted. After 12 months, no progression of the recession could be observed. [ABSTRACT FROM AUTHOR]

Objectives: The objectives of this study are to identify oral commensal species which can inhibit the growth of the main periodontopathogens, to determine the antimicrobial substances involved in these inhibitory activities and to evaluate the influence of environmental factors on the magnitude of these inhibitions.Methods: The spotting technique was used to quantify the capacity of 13 commensal species to inhibit the growth of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis and Prevotella intermedia. By altering experimental conditions (distance between spots and size of spots and concentration of commensal and pathogen) as well as environmental factors (inoculation sequence, oxygen and nutrition availability) the influence of these factors was evaluated. Additionally, the mechanism of inhibition was elucidated by performing inhibition experiments in the presence of peroxidase, trypsin and pepsin and by evaluating acid production.Results: Streptococcus sanguinis, Streptococcus cristatus, Streptococcus gordonii, Streptococcus parasanguinis, Streptococcus mitis and Streptococcus oralis significantly inhibit the growth of all pathogens. The volume of the spots and concentration of the commensal have a significant positive correlation with the amount of inhibition whereas distance between the spots and concentration of the pathogen reduced the amount of inhibition. Inhibition is only observed when the commensal species are inoculated 24h before the pathogen and is more pronounced under aerobic conditions. Hydrogen peroxide production by the commensal is the main mechanism of inhibition.Conclusion: Bacterial antagonism is species specific and depending on experimental as well as environmental conditions. Blocking hydrogen peroxide production neutralizes the inhibitory effect.Clinical Significance: Identifying beneficial oral bacteria and understanding how they inhibit pathogens might help to unravel the mechanisms behind dysbiotic oral diseases. In this context, this study points towards an important role for hydrogen peroxide. The latter might lead in the future to novel preventive strategies for oral health based on improving the antimicrobial properties of commensal oral bacteria. [ABSTRACT FROM AUTHOR]

Objective: The main aim of this in vitro study was to evaluate the influence of Streptococcus mutans on the corrosion of titanium. Methods: S. mutans biofilms were formed on commercially pure titanium (CP-Ti) square samples (10 mm × 10 mm × 1 mm) using a culture medium enriched with sucrose. Open circuit potential (OCP) and electrochemical impedance spectroscopy (EIS) measurements were used to evaluate the corrosion behaviour of CP-Ti in the presence of S. mutans in Fusayama's artificial saliva. The corrosion of biofilm-free CP-Ti samples was also evaluated in artificial saliva. Biofilms biomass was measured by spectrophotometry, using crystal violet staining, after 1, 2 and 7 days. Results: The OCP values recorded on CP-Ti in the presence of S. mutans (0.3 0.02 V vs. SCE) was lower than those on biofilm-free CP-Ti (-0.1 ± 0.01 V vs. SCE) after 2 h of immersion in artificial saliva ( p < 0.05). That reveals a high reactivity of titanium in presence of S. mutans. Impedance spectra revealed the formation of a compact passive film on titanium in artificial saliva or in the presence of a 2 days old S. mutans biofilm even though the corrosion resistance of CP-Ti has decreased in presence of a S. mutans biofilm. Conclusion: The presence of bacterial colonies, such as S. mutans, negatively affected the corrosion resistance of the titanium. [ABSTRACT FROM AUTHOR]