Evaluation of the extent of plaque removal and users' experience of alternative toothbrushes: A randomized single-blind crossover study.

INTRODUCTION: In residential care, tooth brushing with a manual toothbrush can be challenging because of technical difficulties, time consumption and poor patient cooperation, resulting in a sub-optimal cleaning. The study aimed at comparing the efficiency in plaque removal, brushing time and users' experience between three toothbrushes: a single-headed conventional manual toothbrush, a triple-headed manual toothbrush and a U-shaped electric toothbrush. METHODS: This was a single-blind crossover study with three pre-post-test conditions. Participants were 26 dental students divided into fixed pairs to play the role of caregivers and care receivers. Pre/post plaque scores were determined by two independent investigators according to the Quigley-Hein Plaque Index (QHI). Questionnaires evaluated participants' experiences. Statistical tests of significances of differences and ANOVA were performed. RESULTS: Results showed that plaque removal was more effective for the manual toothbrush and the triple-headed toothbrush compared to the U-shaped electric toothbrush (p < 0.001). Brushing time was the longest for the single manual toothbrush (149 s). The U-shaped electric toothbrush showed significantly better results for aspects related to comfort and salivation. The manual and triple-headed toothbrush showed better results for aspects related to cleanliness and motivation to use. CONCLUSION: Notwithstanding its favourable comfort, tooth plaque removal is not enhanced by a U-shaped electric toothbrush. The triple-headed and single-headed toothbrushes reduced plaque more substantially than the U-shaped toothbrush. In addition, the triple-headed manual toothbrush was not only effective in plaque removal, but also had a shorter brushing time and was easy to use, being an adequate alternative for care-dependent patient groups.

Effectiveness of a 3D simulation tool to teach the designing of metal removable partial dentures: A mixed-method study.

INTRODUCTION: Acquiring insights into the framework design of metal-based removable partial dentures (mRPD) is a current challenge in dental education. The aim of the present study was to explore the effectiveness of a novel 3D simulation tool to teach designing mRPD by investigating the learning gain and the acceptance and motivation towards the tool of dental students. MATERIALS AND METHODS: A 3D tool based on 74 clinical scenarios was developed for teaching the design of mRPD. Fifty-three third year dental students were randomly divided into two groups, with the experimental group (n = 26) having access to the tool during 1 week while the control group (n = 27) had no access. Quantitative analysis was based on a pre- and post-test in order to evaluate the learning gain, technology acceptance and motivation towards using the tool. Moreover, qualitative data was collected by means of an interview and focus group to get additional insights into the quantitative results. RESULTS: Although the results showed a higher learning gain for students in the experimental condition, the study did not find a significant difference between both conditions based on quantitative results. However, during the focus groups, all students of the experimental group revealed that the 3D tool improved their understanding of mRPD biomechanics. Moreover, survey results revealed that students positively evaluated the perceived usefulness and ease of use of the tool and indicated to have the intention to use the tool in the future. Suggestions were made for a redesign (e.g. creating scenarios themselves) and further implementation of the tool (e.g. analysing the scenarios in pairs or small groups). CONCLUSION: First results of the evaluation of the new 3D tool for teaching the design framework of mRPD are promising. Further research based on the design-based research methodology is needed to investigate the effects of the redesign on motivation and learning gain.

Effectiveness of implant-supported fixed partial denture in patients with history of periodontitis: A systematic review and meta-analysis.

AIM: This systematic review investigates the effectiveness of implant-supported fixed partial denture (IS-FPD) in patients with history of periodontitis (HP) vs. patients with no history of periodontitis (NHP). METHODS: A literature search was performed on different databases on May 2020. Prospective and retrospective studies assessing survival (primary outcome), success and biological/mechanical complications of IS-FPDs in HP vs. NHP patients at ≥1 year after implant loading were evaluated. Meta-analyses were conducted by estimating hazard ratio (HR), risk ratio (RR) and standardized mean differences (SMD) with 95% confidence intervals (CI) using random effect models. RESULTS: Of the initially identified 4096 articles, 349 underwent a full-text evaluation. Finally, 17 were included. Pooled data analyses showed that overall implant survival was significantly higher in the NHP than the HP group (HR = 2.06; 95% CI = 1.37-3.09; I2  = 0%). This difference was noted when follow-up ≥5 years. The risk of peri-implantitis was higher in HP than NHP patients (RR = 3.3; 95% CI = 1.31-8.3; I2  = 0%), whereas the mean marginal bone level change over time was not different between the groups (SMD = -0.16 mm; 95% CI = -1.04-0.73; I2  = 98%). CONCLUSIONS: In partially edentulous patients receiving IS-FPDs, a history of periodontitis is associated with poorer survival rate and higher risk of peri-implantitis during a 5-10 years period after implant loading.

Is the Jaw Bone Micro-Structure Altered in Response to Osteoporosis and Bisphosphonate Treatment? A Micro-CT Analysis.

The aim of the study was to quantify the micro-architectural changes of the jaw bone in response to ovariectomy, exposed or not to bisphosphonate treatment. A total of 47 Wistar rats were ovariectomized (OVX) or sham-operated (shOVX) and exposed to osteoporosis preventive treatment for eight weeks either with bisphosphonates (alendronate, ALN; group OVX-ALN) three days/week at a dose of 2 mg/kg or with saline solution (untreated control condition; group OVX). The bone morphometric parameters of the trabecular jaw bone were assessed using ex vivo micro-computed tomography. The regions of interest investigated in the maxilla were the inter-radicular septum of the second molar and the tuber. The regions quantified in the mandible included the three molar regions and the condyle. A one-way analysis of variance followed by pairwise comparison using Tukey's HSD and the Games-Howell test was conducted to explore significant differences between the groups. In the maxilla, OVX decreased the bone volume in the inter-radicular septum of the second molar. Bisphosphonate treatment was able to prevent this deterioration of the jaw bone. The other investigated maxillary regions were not affected by (un)treated ovariectomy. In the mandible, OVX had a significant negative impact on the jaw bone in the buccal region of the first molar and the inter-radicular region of the third molar. Treatment with ALN was able to prevent this jaw bone loss. At the condyle site, OVX significantly deteriorated the trabecular connectivity and shape, whereas preventive bisphosphonate treatment showed a positive effect on this trabecular bone region. No significant results between the groups were observed for the remaining regions of interest. In summary, our results showed that the effects of ovariectomy-induced osteoporosis are manifested at selected jaw bone regions and that bisphosphonate treatment is capable to prevent these oral bone changes.

Alteration of the Condylar Oral Bone in Obese and Gastric Bypass Mice.

Obesity is the main cause of type 2 diabetes mellitus (T2DM). Roux-en-Y gastric bypass (RYGB) surgery is an effective treatment for this obesity-related health problem. However, the adverse effects of T2DM on bone tissue persist or even aggravate after this surgical procedure. As studies on the mandibular condyle bone are scarce, the aim of the present study was to assess its compositional characteristics in T2DM and RYGB conditions. Thirty-two male C57BL/6 mice at 8 weeks of age were randomly assigned to receive either a high-fat or low-fat diet. After 14 weeks of high-fat diet intake, seven obese mice were subjected to RYGB surgery. All animals were euthanized at the age of 30 weeks. Mandibular bones were removed and the trabecular condyle region was assessed using Raman spectroscopy. A decreased mineralization was observed for both T2DM and RYGB condyle bones when compared to controls, with elevated carbonate substitutions for the RYGB group. No compositional differences in crystallinity and presence of advanced glycation end products were found between the groups, with the exception of an increased presence of N-carboxymethyl-lysine in RYGB bone compared to their T2DM counterpart. Site-specific measurements revealed a non-uniform bone composition, with increasing mineralization and carbonate substitutions towards the centre of the mandibular condyle. T2DM and RYGB surgery affect the mandibular condyle bone quality, as investigated at compositional level. Assessment of bone structural properties and remodelling should be carried out to further explore the effects of T2DM and RYGB surgery on this skeleton area.

A core curriculum in the biological and biomedical sciences for dentistry.

INTRODUCTION: The biomedical sciences (BMS) are a central part of the dental curriculum that underpins teaching and clinical practice in all areas of dentistry. Although some specialist groups have proposed curricula in their particular topic areas, there is currently no overarching view of what should be included in a BMS curriculum for undergraduate dental programmes. To address this, the Association for Dental Education in Europe (ADEE) convened a Special Interest Group (SIG) with representatives from across Europe to develop a consensus BMS curriculum for dental programmes. CURRICULUM: This paper summarises the outcome of the deliberations of this SIG and details a consensus view from the SIG of what a BMS curriculum should include. CONCLUSIONS: Given the broad nature of BMS applied to dentistry, this curriculum framework is advisory and seeks to provide programme planners with an indicative list of topics which can be mapped to specific learning objectives within their own curricula. As dentistry becomes increasingly specialised, these will change, or some elements of the undergraduate curriculum may move to the post-graduate setting. So, this document should be seen as a beginning and it will need regular review as BMS curricula in dentistry evolve.

Repurposing Toremifene for Treatment of Oral Bacterial Infections.

The spread of antibiotic resistance and the challenges associated with antiseptics such as chlorhexidine have necessitated a search for new antibacterial agents against oral bacterial pathogens. As a result of failing traditional approaches, drug repurposing has emerged as a novel paradigm to find new antibacterial agents. In this study, we examined the effects of the FDA-approved anticancer agent toremifene against the oral bacteria Porphyromonas gingivalis and Streptococcus mutans We found that the drug was able to inhibit the growth of both pathogens, as well as prevent biofilm formation, at concentrations ranging from 12.5 to 25 µM. Moreover, toremifene was shown to eradicate preformed biofilms at concentrations ranging from 25 to 50 µM. In addition, we found that toremifene prevents P. gingivalis and S. mutans biofilm formation on titanium surfaces. A time-kill study indicated that toremifene is bactericidal against S. mutans Macromolecular synthesis assays revealed that treatment with toremifene does not cause preferential inhibition of DNA, RNA, or protein synthesis pathways, indicating membrane-damaging activity. Biophysical studies using fluorescent probes and fluorescence microscopy further confirmed the membrane-damaging mode of action. Taken together, our results suggest that the anticancer agent toremifene is a suitable candidate for further investigation for the development of new treatment strategies for oral bacterial infections.

Titanium implant functionalization with phosphate-containing polymers may favour in vivo osseointegration.

AIM: Osseointegration of titanium implants is predictable, but can be improved via surface functionalization. MATERIALS AND METHODS: One hundred and twenty implants were installed in parietal bone of 12 domestic pigs and left to heal for 1 or 3 months. Five groups were defined according surface treatments: immersion in water (H2 O), 10% polyphosphoric acid (PPA10), 1% phosphorylated pullulan (PPL1), 10% phosphorylated pullulan (PPL10) or 10% phosphorylated pullulan + 1 µg bone morphogenetic protein-2 (PPL10 BMP). As primary outcome, implant osseointegration was evaluated by quantitative histology, namely peri-implant bone formation (B/T in %) and bone-to-implant contact (BIC in %) for each healing period. The Wilcoxon signed-rank test and Mann-Whitney U-test with α = 0.05 were performed. RESULTS: PPL10 and PPA10 groups showed significantly higher B/T and BIC results than the control (H2 O) group at 1-month (p < .05). No significant difference was found between PPL1 and H2 O or between PPL10 BMP and H2 O, irrespective of healing time (1 or 3 months) or investigated parameter (B/T and BIC; p > .05). After 3 months, no experimental group showed a significant difference compared to the control group (H2 O) for both investigated parameters (B/T and BIC; p > .05). CONCLUSION: Functionalizing titanium implants with inorganic or organic phosphate-containing polymers at 10 wt% concentration may stimulate peri-implant bone formation and implant osseointegration at early healing times.

Covalent immobilization of antimicrobial agents on titanium prevents Staphylococcus aureus and Candida albicans colonization and biofilm formation.

OBJECTIVES: Biofilm-associated implant infections represent a serious public health problem. Covalent immobilization of antimicrobial agents on titanium (Ti), thereby inhibiting biofilm formation of microbial pathogens, is a solution to this problem. METHODS: Vancomycin (VAN) and caspofungin (CAS) were covalently bound on Ti substrates using an improved processing technique adapted to large-scale coating of implants. Resistance of the VAN-coated Ti (VAN-Ti) and CAS-coated Ti (CAS-Ti) substrates against in vitro biofilm formation of the bacterium Staphylococcus aureus and the fungal pathogen Candida albicans was determined by plate counting and visualized by confocal laser scanning microscopy. The efficacy of the coated Ti substrates was also tested in vivo using an adapted biomaterial-associated murine infection model in which control-Ti, VAN-Ti or CAS-Ti substrates were implanted subcutaneously and subsequently challenged with the respective pathogens. The osseointegration potential of VAN-Ti and CAS-Ti was examined in vitro using human bone marrow-derived stromal cells, and for VAN-Ti also in a rat osseointegration model. RESULTS: In vitro biofilm formation of S. aureus and C. albicans on VAN-Ti and CAS-Ti substrates, respectively, was significantly reduced compared with biofilm formation on control-Ti. In vivo, we observed over 99.9% reduction in biofilm formation of S. aureus on VAN-Ti substrates and 89% reduction in biofilm formation of C. albicans on CAS-Ti substrates, compared with control-Ti substrates. The coated substrates supported osseointegration in vitro and in vivo. CONCLUSIONS: These data demonstrate the clinical potential of covalently bound VAN and CAS on Ti to reduce microbial biofilm formation without jeopardizing osseointegration.

Hind limb unloading, a model of spaceflight conditions, leads to decreased B lymphopoiesis similar to aging.

Within the bone marrow, the endosteal niche plays a crucial role in B-cell differentiation. Because spaceflight is associated with osteoporosis, we investigated whether changes in bone microstructure induced by a ground-based model of spaceflight, hind limb unloading (HU), could affect B lymphopoiesis. To this end, we analyzed both bone parameters and the frequency of early hematopoietic precursors and cells of the B lineage after 3, 6, 13, and 21 d of HU. We found that limb disuse leads to a decrease in both bone microstructure and the frequency of B-cell progenitors in the bone marrow. Although multipotent hematopoietic progenitors were not affected by HU, a decrease in B lymphopoiesis was observed as of the common lymphoid progenitor (CLP) stage with a major block at the progenitor B (pro-B) to precursor B (pre-B) cell transition (5- to 10-fold decrease). The modifications in B lymphopoiesis were similar to those observed in aged mice and, as with aging, decreased B-cell generation in HU mice was associated with reduced expression of B-cell transcription factors, early B-cell factor (EBF) and Pax5, and an alteration in STAT5-mediated IL-7 signaling. These findings demonstrate that mechanical unloading of hind limbs results in a decrease in early B-cell differentiation resembling age-related modifications in B lymphopoiesis.

The impact of autologous platelet concentrates on endodontic healing: a systematic review.

The current literature was reviewed to determine the impact of autologous platelet concentrates (APCs) on endodontic healing. All types of clinical study designs concerning any kind of endodontic treatment involving the application of APCs were included. Two independent reviewers searched three databases (PubMed, Embase, and Cochrane Library) for studies, complemented by hand search, until 16/1/2016. From the 423 identified records, 48 articles met the inclusion criteria. Selected randomized controlled clinical trials (RCTs) underwent Cochrane Collaboration's risk-of-bias assessment and data extraction. Only two RCTs showed low risk of bias. There was considerable heterogeneity between the RCTs with regard to the type of therapy, type of APCs, assessment method, and study quality, and therefore the data could not be analyzed quantitatively. The included case reports/series and non-randomized comparative studies underwent qualitative analysis with the revised Methodological Index for Non-Randomized Studies (MINORS) and data extraction. The two comparative non-randomized studies scored qualitatively high, though the MINORS-scores of the case series and reports were dispersed. APCs were involved in five endodontic treatment modalities, namely apexification, regenerative endodontic procedures, pulpotomy, apical surgery, and treatment of endo-perio/perio-endo lesions. APCs seem to accelerate postoperative bone healing, augment the patients' postoperative quality of life, aid further root development, and support maintenance/regaining of pulp vitality. No adverse events were reported. APCs in endodontic treatments seem to contribute to the healing of soft and hard tissues, though there is a lack of long-term high quality clinical trials and standardized treatment protocols.

Effect of insertion torque on titanium implant osseointegration: an animal experimental study.

OBJECTIVE: To evaluate the effect of implant insertion torque on the peri-implant bone healing and implant osseointegration. MATERIAL AND METHODS: Bilaterally in the tibia of five adult New Zealand white rabbits, 20 implants were installed, subdivided into four groups, corresponding to two insertion torque conditions (low, < 10 Ncm vs. high > 50 Ncm) and 2 experimental periods (2 weeks vs. 4 weeks of healing). The implant insertion torque was determined by the surgical drill diameter relative to the implant diameter. Implant osseointegration was evaluated by quantitative histology (bone-to-implant contact with host bone [BIC-host], with neoformed bone [BIC-de novo], with both bone types [BIC-total], and peri-implant bone [BA/TA]). Every response was modelled over time using GEE (general estimation equation) with an unstructured variance-covariance matrix to correct for dependency between the measurements from one animal. The statistical significance level of α = 0.05 was applied. RESULTS: Significantly, more BIC-host and BIC-total were recorded for H implants compared with L implants after 2 week of healing (P = 0.010 and P = 0.0001, respectively). However, this result was no longer found for the extended healing period. Furthermore, BIC-total significantly increased over time for L implants (P < 0.00001). In contrast, the significant increase in BA/TA over time was found for H implants (P < 0.01). Finally, H insertion torque led to an increased BA/TA after 4 week of healing (P < 0.02) compared with the L insertion protocol. CONCLUSION: L insertion torque implants installed in the rabbit tibial bone osseointegrate with considerable de novo bone formation. This bone neoformation enables L implants to catch up, already during the early osseointegration stage, the initial inferior amount BIC contact compared with that of H implants. A negative impact of the created strain environment accompanying H insertion torque implant installation on the biological process of osseointegration could not be observed, at least not at tissue level.

Repurposing as a means to increase the activity of amphotericin B and caspofungin against Candida albicans biofilms.

OBJECTIVES: Biofilms of Candida species, often formed on medical devices, are generally resistant to currently available antifungal drugs. The aim of this study was to identify compounds that increase the activity of amphotericin B and caspofungin, commonly used antifungal agents, against Candida biofilms. METHODS: A library containing off-patent drugs was screened for compounds, termed enhancers, that increase the in vitro activity of amphotericin B against Candida albicans biofilms. Biofilms were grown in 96-well plates and growth was determined by the cell titre blue assay. Synergy between identified enhancers and antifungal agents was further characterized in vitro using fractional inhibitory concentration index (FICI) values and in vivo using a worm biofilm infection model. In light of the application of these enhancers onto implants, their possible effect on the growth potential of MG63 osteoblast-like cells was assessed. RESULTS: Pre-incubation of C. albicans biofilms with subinhibitory concentrations of the enhancers drospirenone, perhexiline maleate or toremifene citrate significantly increased the activity of amphotericin B or caspofungin (FICI  < 0.5) against C. albicans and Candida glabrata biofilms. Moreover, these enhancers did not affect the growth potential of osteoblasts. Interestingly, toremifene citrate also enhanced the in vitro activity of caspofungin in a mixed biofilm consisting of C. albicans and Staphylococcus epidermidis. Furthermore, we demonstrate synergy between toremifene citrate and caspofungin in an in vivo worm C. albicans biofilm infection model. CONCLUSIONS: Our data demonstrate an in vitro and in vivo enhancement of the antibiofilm activity of caspofungin by toremifene citrate. Furthermore, our results pave the way for implant-related applications of the identified enhancers.

Stimulation of titanium implant osseointegration through high-frequency vibration loading is enhanced when applied at high acceleration.

Low-magnitude high-frequency loading, applied by means of whole body vibration (WBV), affects the bone. Deconstructing a WBV loading stimulus into its constituent elements and investigating the effects of frequency and acceleration individually on bone tissue kinetics around titanium implants were aimed for in this study. A titanium implant was inserted in the tibia of 120 rats. The rats were divided into 1 control group (no loading) and 5 test groups with low (L), medium (M) or high (H) frequency ranges and accelerations [12-30 Hz at 0.3×g (F(L)A(H)); 70-90 Hz at 0.075×g (F(M)A(M)); 70-90 Hz at 0.3×g (F(M)A(H)); 130-150 Hz at 0.043×g (F(H)A(L)); 130-150 Hz at 0.3×g (F H A H)]. WBV was applied for 1 or 4 weeks. Implant osseointegration was evaluated by quantitative histology (bone-to-implant contact (BIC) and peri-implant bone formation (BV/TV)). A 2-way ANOVA (duration of experimental period; loading mode) with α = 0.05 was performed. BIC significantly increased over time and under load (p < 0.0001). The highest BICs were found for loading regimes at high acceleration with medium or high frequency (F(M)A(H) and F(H)A(H)), and significantly differing from F(L)A(H) and F(M)A(M) (p < 0.02 and p < 0.005 respectively). BV/TV significantly decreased over time (p < 0.0001). Loading led to a site-specific BV/TV increase (p < 0.001). The highest BV/TV responses were found for F(M)A(H) and F(H)A(H), significantly differing from F(M)A(M) (p < 0.005). The findings reveal the potential of high-frequency vibration loading to accelerate and enhance implant osseointegration, in particular when applied at high acceleration. Such mechanical signals hold great, though untapped, potential to be used as non-pharmacologic treatment for improving implant osseointegration in compromised bone.

Evaluation of plaque removal by a single-headed versus a triple-headed manual toothbrush using different plaque assessment tools.

Background: Dental plaque is a common issue that can be effectively managed with proper oral hygiene practices and regular oral health care. The aim of this crossover study was to assess dental plaque using different methods (digital and clinical plaque scores) and evaluate the effectiveness of toothbrushing with a triple-headed manual toothbrush compared to a single-headed manual toothbrush in removing dental plaque. Methods: Plaque staining was performed to assess dental plaque amounts before and after brushing with the triple-headed (test) and single-headed (control) manual toothbrush in 21 study participants after plaque was allowed to accumulate for 48 hours. Dental plaque was scored both clinically as well as digitally. Results: Toothbrushing with a manual single-headed toothbrush and a triple-headed toothbrush was found to be equally effective when comparing plaque removal ability. Brushing time was shorter when using a triple-headed toothbrush, compared to a single-headed toothbrush. Conclusion: The triple-headed manual toothbrush may be a good alternative to the single-headed manual toothbrush for certain patient groups.

Contexte: La plaque dentaire est un problème courant qui peut être géré efficacement en adoptant de bonnes pratiques d'hygiène buccale et en obtenant régulièrement des soins buccodentaires. L'objectif de cette étude croisée était d'évaluer l'état de la plaque dentaire à l'aide de différentes méthodes (cotes de plaque numériques et cliniques) et d'évaluer l'efficacité du brossage à l'aide d'une brosse à dents manuelle à 3 côtés comparativement au brossage avec une brosse à dents manuelle à 1 côté pour éliminer la plaque dentaire. Méthodes: On a coloré la plaque dentaire pour en évaluer la quantité avant et après le brossage avec une brosse à dents manuelle à 3 côtés (essai) et à 1 côté (contrôle) parmi les 21 participants à l'étude après avoir laissé la plaque s'accumuler pendant 48 heures. On a attribué une cote clinique et numérique à la plaque dentaire. Résultats: Le brossage avec une brosse à dents manuelle à 3 côtés s'est révélé tout aussi efficace que le brossage avec une brosse manuelle à 1 côté sur le plan de l'élimination de la plaque. Le temps de brossage était plus court avec une brosse à dents à 3 côtés qu'avec une brosse à dents à 1 côté. Conclusion: Pour certains groupes de patients, la brosse à dents à 3 côtés peut être une bonne alternative à la brosse à dents ordinaire.

Bone tissue response to BMP-2 adsorbed on amorphous microporous silica implants.

AIM: To evaluate bone regeneration potential of bone morphogenetic protein-2 (BMP-2) adsorbed on amorphous microporous silica (AMS). MATERIALS & METHODS: Four implants [titanium as control (CTR); AMS-coated titanium (AMS), BMP-2 adsorbed on titanium (CTR+BMP) and AMS (AMS+BMP)] were implanted randomly in the tibiae of 20 New Zealand white rabbits. Bone specimens with implants were retrieved 2/4 weeks post implantation and analysed histologically and histomorphometrically. Bone fraction was measured in initial bone-free area (bone regeneration area, BRA) and in the area with initial bone-implant contact [bone adaptation area (BAA)] (BF(BRA) & BF(BAA) ). Bone-implant contact was measured in BRA (BIC(BRA) ). In vitro BMP-2 release profiles were determined to evaluate the impact of the carrier surface. Mixed models were used for statistical analysis. RESULTS: BMP-2 release profiles were different for CTR+BMP and AMS+BMP. BIC(BRA) and BF(BRA) were significantly increased after 4 weeks compared to 2 weeks for AMS, CTR+BMP and AMS+BMP. However, no differences between the implant types were observed within both healing periods. BF(BAA) for CTR+BMP was smaller than that for CTR and AMS+BMP after 4 weeks. Despite slower BMP-2 release, AMS+BMP did not stimulate bone regeneration. CTR+BMP caused bone resorption at the bone-implant interface. CONCLUSIONS: BMP-2 functionalized implant surfaces failed to stimulate bone regeneration and osseointegration.

Occlusal overload and bone/implant loss.

AIM: The aim of this search was to assess the biological consequences that overload might have on already osseointegrated oral implants through a systematic screening of the scientific literature. METHOD: Detailed searches through PUBMED, OVID, EMBASE and LILACS databases were made. Articles published up to December 2011 and those reported on the clinical, radiographic and/or histological outcome of oral implants subjected to so-called overload were considered eligible for inclusion. Identified studies were assessed by one non-blinded reviewer according to well-defined inclusion and exclusion criteria. When doubt arose, the co-authors were counselled until final agreement was obtained. The PICO questions formulated was:"what is the effect of overload vs. no overload on bone/implant loss in clinically stable implants?" RESULTS: The database searches as well as additional hand searching, resulted in 726 potentially relevant titles. Eventually, 16 clinical and 25 animal studies were considered relevant to the topic. After inclusion/exclusion criteria assessment, all clinical studies and all but three animal studies and one systematic review were considered at high risk of bias and excluded. The included animal studies did not reveal an association between overload and peri-implant bone loss in the absence of peri-implant inflammation, whereas in its presence, overload seemed to aggravate the peri-implant tissue breakdown. CONCLUSIONS: The effect of implant overload on bone/implant loss in clinically well-integrated implants is poorly reported and provides little unbiased evidence to support a cause-and-effect relationship. The PICO question remained unanswered. At the animal level, "overload", mimicked by supra-occlusal contacts acting in an uninflamed peri-implant environment, did not negatively affect osseointegration and even was anabolic. In contrast, supra-occlusal contacts in the presence of inflammation significantly increased the plaque-induced bone resorption.

Impaired soft and hard callus formation during fracture healing in diet-induced obese mice as revealed by 3D contrast-enhanced computed tomography imaging.

The impact of diabetes mellitus on bone fracture healing is clinically relevant as the patients experience delayed fracture healing. Even though efforts have been made to understand the detrimental effects of type 2 diabetes mellitus (T2DM) on the fracture healing process, the exact mechanisms causing the pathophysiological outcomes remain unclear. The aim of this study was to assess alterations in bone fracture healing (tibial fracture surgery, intramedullary pinning) of diet-induced obese (DIO) mice, and to investigate the in vitro properties of osteochondroprogenitors derived from the diabetic micro-environment. High-resolution contrast-enhanced microfocus X-ray computed tomography (CE-CT) enabled a simultaneous 3D assessment of the amount and spatial distribution of the regenerated soft and hard tissues during fracture healing and revealed that osteogenesis as well as chondrogenesis are altered in DIO mice. Compared to age-matched lean controls, DIO mice presented a decreased bone volume fraction and increased callus volume and adiposity at day 14 post-fracture. Of note, bone turnover was found altered in DIO mice relative to controls, evidenced by decreased blood serum osteocalcin and increased serum CTX levels. The in vitro data revealed that not only the osteogenic and adipogenic differentiation of periosteum-derived cells (PDCs) were altered by hyperglycemic (HG) conditions, but also the chondrogenic differentiation. Elevated PPARγ expression in HG conditions confirmed the observed increase in differentiated adipocytes in vitro. Finally, chondrogenesis-related genes COL2 and COL10 were downregulated for PDCs treated with HG medium, confirming that chondrogenic differentiation is compromised in vitro and suggesting that this may affect callus formation and maturation during the fracture healing process in vivo. Altogether, these results provide novel insights into the alterations of long bone fracture repair and suggest a link between HG-induced dysfunctionality of osteochondroprogenitor differentiation and fracture healing impairment under T2DM conditions.

Oral Implant Restorations By Undergraduate Students: An Up To 5-Years Clinical Outcome.

PURPOSE: To clinically evaluate oral implant restorations placed by undergraduate students in the dental clinical curriculum at KU Leuven (Belgium) in terms of function and esthetics. MATERIALS AND METHODS: A retrospective observational cohort study was designed. The esthetic and functional evaluations of implant-supported restorations placed in the framework of the undergraduate implant dentistry clinical training program using White/Pink Esthetic Score (WES/PES) and visual analog scale (VAS) scoring was performed. Furthermore, complications were registered based retrospectively on the patient's medical file. The following research questions were stipulated: (1) How well do implant-supported restorations placed by undergraduate students perform esthetically? and (2) Which complications occurred and how were these managed? RESULTS: Between August 2008 and July 2014 (6 academic terms), 251 implants (Brånemark System Mk III, Nobel Biocare) were placed in 113 patients by 155 students (> 40% of all students enrolled in the training program). Of these implants, 228 were restored in 101 patients by 118 students with varying restoration types. Esthetic scoring of the restorations in 83 of these patients revealed a satisfying mean WES of 8.14 ± 2.09 (out of 10) and PES of 9.56 ± 3.14 (out of 14). Complications were registered in 18.9% of the cases. DISCUSSION: Clinical training in implant dentistry for undergraduates contributes to the development of advanced skills in the dental student's Master education. Overall, patients were satisfied with their implant-supported restorations. Implant and restoration success rates and complication incidence were confirmed by long-term data in the oral implant literature.

Regenerative Endodontic Procedure of Immature Permanent Teeth with Leukocyte and Platelet-rich Fibrin: A Multicenter Controlled Clinical Trial.

INTRODUCTION: 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). METHODS: 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. RESULTS: 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). CONCLUSIONS: 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.