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To achieve re-osseointegration on implant surfaces exposed to peri-implant infections, treatment should re-establish biocompatibility. The aim of this study was to test whether air powder abrasive treatment (APA) using osteoconductive powders can, in addition to cleaning, increase the biocompatibility of the contaminated implant surface. Ninety-six in vitro Ca-precipitated, organic film layer–coated sandblasted and acid-etched titanium discs were treated by APA using erythritol, hydroxylapatite (HA), and biocalcium phosphate (BioCaP) powders (n = 16 per group). Six treatment modalities were created (HA or erythritol cleaning with/without BioCaP coating). MC3T3-E1cells were seeded on discs, and cell attachment, viability, proliferation, and differentiation were evaluated. Pristine discs were used as control (control 1). Contaminated and nontreated discs were used as control (control 2). The cells were stretched and attached in all test groups. The cell viability and proliferation (DNA amount) in all test groups were significantly higher than in the pristine and contaminated disc groups. There was no significant difference between the test groups. The differentiation (alkaline phosphatase activity) of the cells on treated discs was significantly higher than on the contaminated discs but lower than in the pristine group. The cell viability in control 2 was significantly lower than the control 1. The APA with osteoconductive powder on contaminated titanium surfaces promoted the cell viability, proliferation, and differentiation of the MC3T3-E1 cells. The biocompatibility of the surface was higher than that of the contaminated discs. The tested aspects of cell response, with the exception of differentiation, reached to the level of the pristine surface. The in vitro results showed that APA with osteoconductive powders could be a promising method for implant surface treatment.

Purpose: The aim of this 1-year randomized trial was to determine the stability and the magnitude of the effect of converting patients' conventional mandibular dentures to implant overdentures (IODs) on their satisfaction and oral health-related quality of life (OHRQoL). The IODs were retained either with two immediately loaded interconnected standard-diameter implants or with four immediately loaded mini dental implants (MDIs). Materials and Methods: Fifty completely edentulous subjects complaining about insufficient retention of their mandibular dentures were randomly assigned to two groups; 25 patients received IODs retained with four MDIs and 25 patients received IODs retained with two standard-sized tissue level (STL) interconnected implants. All IODs were opposed by conventional maxillary dentures. Patients rated their satisfaction on a 100-mm visual analog scale (VAS) and their quality of life on a denture-specific short version of the oral health impact profile (OHIP-20) before assignment, and after 3 and 12 months. A two-way mixed analysis of variance (ANOVA) was conducted to assess the change in time and its interaction with treatment mode on patients' overall satisfaction ratings, the total OHIP-20, and their specific domain scores. Results: Immediate loading was possible for all the patients who received the MDIs. By contrast, the immediate loading protocol could be followed for only 15 of the patients allocated to the STL implant group. For the remaining patients, a delayed loading protocol was applied. There was a significant improvement in patients' general satisfaction between baseline and 3 months and between baseline and 12 months postoperatively (F2,44 = 81.006, P < .001). This increase did not differ between the treatment groups (F4,90 = 1.838, P = .128). The results also showed a decrease in mean overall OHIP score (F2,43 = 46.863, P < .001) between baseline and 3 months and between baseline and 12 months postoperatively, indicating a higher level of OHRQoL. In addition, patients scored lower 3 and 12 months after treatment than at baseline for all seven domains. This decrease did not differ between the treatment groups (F4,88 = 0.608, P = .658). Conclusion: The results suggested that in terms of patient-based outcomes, mandibular overdentures retained by immediately loaded MDIs can offer an improvement of equal magnitude with that achieved by overdentures retained by standard-sized implants.

Background and Objective Nowadays, most designs for the transmucosal surface of implants are machined-smooth. However, connective tissue adhered to the smooth surface of an implant has poor mechanical resistance, which can render separation of tissue from the implant interface and induce epithelial downgrowth. Modification of the transmucosal surface of implants, which can help form a good seal of connective tissue, is therefore desired. We hypothesized that anodic oxidation (AO) and polydopamine (PD) deposition could be used to enhance the attachment between an implant and peri-implant connective tissue. We tested this hypothesis in the mandibles of Beagle dogs. Material and Methods AO and PD were used to modify the transmucosal region of transmucosal implants (implant neck). The surface microstructure, surface roughness and elemental composition were investigated in vitro. L929 mouse fibroblasts were cultured to test the effect of PD on cell adhesion. Six Beagle dogs were used for the in vivo experiment (n = 6 dogs per group). Three months after building the edentulous animal model, four groups of implants (control, AO, PD and AO + PD) were inserted. After 4 months of healing, samples were harvested for histometric analyses. Results The surfaces of anodized implant necks were overlaid with densely distributed pores, 2–7 μm in size. On the PD-modified surfaces, N1s, the chemical bond of nitrogen in PD, was detected using X-ray photoelectron spectroscopy. L929 developed pseudopods more quickly on the PD-modified surfaces than on the surfaces of the control group. The in vivo experiment showed a longer connective tissue seal and a more coronally located peri-implant soft-tissue attachment in the AO + PD group than in the control group (P

Exosomes, nanoscale extracellular vesicles functioning as cell-to-cell communicators, are an emerging promising therapeutic in the field of bone tissue engineering. Here, we report the construction and evaluation of a novel cell-free tissue-engineered bone that successfully accelerated the restoration of critical-sized mouse calvarial defects through combining exosomes derived from human adipose-derived stem cells (hASCs) with poly(lactic-co-glycolic acid) (PLGA) scaffolds. The exosomes were immobilized on the polydopamine-coating PLGA (PLGA/pDA) scaffolds under mild chemical conditions. Specifically, we investigated the effects of hASC-derived exosomes on the osteogenic, proliferation, and migration capabilities of human bone marrow-derived mesenchymal stem cells in vitro and optimized their osteoinductive effects through osteogenic induction. Furthermore, an in vitro assay showed exosomes could release from PLGA/pDA scaffold slowly and consistently and in vivo results showed this cell-free system enhanced bone regeneration significantly, at least partially through its osteoinductive effects and capacities of promoting mesenchymal stem cells migration and homing in the newly formed bone tissue. Therefore, overall results demonstrated that our novel cell-free system comprised of hASC-derived exosomes and PLGA/pDA scaffold provides a new therapeutic paradigm for bone tissue engineering and showed promising potential in repairing bone defects.

Esthetische implantologie is een veelgebruikte behandelmodaliteit om tot functioneel en esthetisch herstel te komen van de dentitie in de esthetische zone. Er zijn verschillende factoren die kunnen leiden tot aanzienlijke botdefecten. Deze botdefecten zijn in te delen in een classificatie, die leidend is voor de te bepalen therapie. Naast deze classificatie zal er een afweging moeten worden gemaakt of de zachte weefselverhoudingen adequaat zijn en of de conditie van de patiënt goed genoeg is om de ingrepen te kunnen ondergaan. Soms is het mogelijk direct na verwijdering van het element een implantaat te plaatsen, wat esthetische voordelen met zich meebrengt. Als dit niet kan, is het van belang de chirurgische interventies zo beperkt mogelijk te houden. Is fixatie van het implantaat in de ‘comfortzone’ mogelijk, dan is gecombineerd plaatsen van het implantaat met een botopbouw (guided bone regeneration) de aangewezen therapie. Is er te weinig bot voor fixatie van het implantaat in de comfortzone, dan is apart opbouwen van het kaakbot, bij voorkeur met bot uit de schedel, de te volgen techniek.

Ernstig beschadigde molaren kunnen door autotransplantatie worden vervangen met behulp van 3D-technieken. Bij een 18-jarige patiënt werden gebitselementen 18, 38 en 48 gebruikt om respectievelijk de gebitselementen 14, 36 en 37 te vervangen. Preoperatief werd met behulp van 3D-beeldvorming de breedte van de kroon en wortelafvorming van de gebitselementen 18, 38 en 48 geanalyseerd. Tijdens de autotransplantatieprocedure werd de nieuwe tandkas gevormd met behulp van 3D-geprinte replica’s van de donorelementen, om zo iatrogene schade van de daadwerkelijke donorelementen te voorkomen. De extra-alveolaire tijd was minder dan 2 minuten bij alle donormolaren. Bij postoperatieve controle was fysiologische integratie te zien van de getransplanteerde molaren. Er was geen sprake van ankylose. Autotransplantatie met behulp van 3D-technieken kan ingewikkelde procedures mogelijk maken met succesvol resultaat.

IntroductionThere is a high incidence of a second mesiobuccal root canal (MB2) in maxillary molars. The study aim is to assess the accuracy of cone-beam computed tomographic (CBCT) imaging in detecting a second mesiobuccal root canal in endodontically treated maxillary molars.MethodsThe study sample consisted of 60 extracted maxillary molars, which were endodontically opened and examined under a dental operating microscope for the presence of an MB2. The teeth were then further examined using micro-computed tomographic imaging as the gold standard. Root canals were filled (except the MB2) and were then subdivided into an experimental and a control group. After fixing the teeth in a dry human skull, they were scanned using CBCT imaging (AccuiTomo 170; Morita Inc, Tarumi-cho Suita City, Osaka, Japan). The observers for this study were 2 experienced radiologists blinded to the group allocation of controls and experiments; they evaluated the images twice independently. Sensitivity, specificity, and accuracy were calculated as well as the kappa values for both inter- and intraobserver agreement.ResultsFrom 30 teeth, which were diagnosed without an MB2 under examination with a dental operating microscope, 6 teeth proved to have an MB2 using μCT (20%). Intraobserver reliability was high for both observers 1 (R = 0.85) and 2 (R = 0.96). Interobserver reliability as assessed by the Cohen kappa was excellent (R = 0.89). CBCT sensitivity for detecting an MB2 was 96%, specificity was 100%, and total accuracy was 98%.ConclusionsCBCT imaging is a suitable diagnostic technique for detecting a missed MB2 in endodontically treated teeth.

Icariin, the primary active ingredient of Herba Epimedii which has been used for decades to treat bone related maladies in China, has the ability to support bone regeneration. In this study, we investigated icariin's potential to stimulate osteogenesis using an in vitro studies to compare icariin's ability as a function of time and dose to induce osteoblastogenesis in MC3T3-E1 cells with that of recombinant human bone morphogenetic protein 2 (rhBMP2). The optimal concentration of icariin in stimulating the proliferation of MC3T3-E1 was 10-5 M. There is no significant difference between icariin and rhBMP2 relative to cell proliferation, alkaline phosphatase (ALP) activity, and osteocalcin (OCN) expression. Icariin had better ALP activity after a 7 day culture and OCN expression after 4 and 10 day cultures compared with rhBMP2. Moreover, icariin produced more mineralized nodules of a larger area than rhBMP2. However, compared with rhBMP2, icariin only showed a significantly higher ALP gene expression on day 4, a 3 fold BMP2 expression on day 7, and Col 1 expression on day 4. In conclusion, compared with rhBMP2, the results indicate that icariin could be a good option for bone regeneration clinically, since it is an inexpensive and safe drug with an excellent osteogenesis potential.

ObjectiveRoles of bone morphogenetic proteins (BMPs) on osteogenesis of human adipose-derived stem cells (hASCs) remain ambiguous. In this study, we evaluated in vitro and in vivo functional characteristics of BMPs of different dimerization types, with the aim of determining osteoinductive efficiency of heterodimeric BMP-2/7 on osteogenesis of hASCs.Materials and methodsWe explored osteoinductive effects of three different BMPs by using cell DNA assay, alkaline phosphatase (ALP) activity assay, alizarin red staining and mineralization assay, and real-time PCR, in vitro. Also, we examined ectopic bone formation in nude mice by using soft X-ray, histomorphometric and immunohistochemical analyses in vivo.ResultsIn our dose-response study, we showed that BMPs with both dimerization types did not induce in vitro osteogenesis of hASCs without osteogenic medium (OM). In the presence of OM, BMPs significantly enhanced hASC osteogenesis in a dose-dependent manner. In in vivo experiments, our analyses indicated that BMPs promoted osteogenesis of hASCs without in vitro osteogenic induction. However, both in vitro and in vivo, there were no significant differences in hASC osteogenic induction between heterodimeric and homodimeric BMPs.ConclusionsHeterodimeric BMP-2/7 significantly promoted osteogenesis of hASCs in vitro and in vivo. However, BMP-2/7 was not found to be a stronger inducer of osteogenesis compared to homodimeric either BMP-2 or BMP-7.

The goal of the current publication is to provide a comprehensive literature review on the topic of dental implant materials. The following paper focuses on conventional titanium implants and more recently introduced and increasingly popular zirconia implants. Major subtopics include the material science and the clinical considerations involving both implant materials and the influence of their physical properties on the treatment outcome. Titanium remains the gold standard for the fabrication of oral implants, even though sensitivity does occur, though its clinical relevance is not yet clear. Zirconia implants may prove to be promising in the future; however, further in vitro and well-designed in vivo clinical studies are needed before such a recommendation can be made. Special considerations and technical experience are needed when dealing with zirconia implants to minimize the incidence of mechanical failure.

Purpose: Safe loading of dental implants requires an optimal osseointegration. This osseointegration process during healing could be analyzed by resonance frequency analysis (RFA). The purpose of the study was to evaluate RFA changes during healing in splinted, early-loaded, thermal acid-etched, hydrophilic implants over time. Materials and Methods: Patients received a minimum of two implants: an implant with the prosthetic abutment connection at the crestal bone level (bone level) and one with the prosthetic abutment connection at a 2.5-mm supracrestal site (tissue level). Implant stability was measured at weeks 0, 2, 3, and 12 using the Osstell device. Results: Seventy-six implants were placed in 32 patients. By week 2, early-loaded tissue-level implants showed a significant drop in mean ± standard deviation (SD) implant stability quotient (ISQ) values of 2.2 ± 3.6 (P < .001). Changes in ISQ values were significant between weeks 3 and 12 and also between weeks 0 and 12, with mean differences of 4.2 (P < .001) and 2.8 (P < .001), respectively. Early-loaded bone-level implants show a significant change in ISQ of 2.3 ± 3.7 at week 2 (P < .01) and -1.3 ± 4.7 at week 12 when compared to an ISQ value of 2.9 ± 4.9 at week 3 (P < .01). Bone-level implants achieved higher ISQ values compared with tissue-level implants at weeks 0, 2, 3, and 12, with mean differences being 3.8 ± 5.5 (P < .01), 3.8 ± 6.1 (P < .01), 3.7 ± 6.7 (P < .01), and 2.3 ± 5.8 (P < .05), respectively. Conclusion: This study found a significant dip in ISQ values, with the lowest point seen at week 2. ISQ values remained higher in bone-level implants throughout the process of healing and osseointegration.

Shuli Deng,1 Ying Wang,1 Wei Sun,1 Hui Chen,1 Gang Wu21Department of Conservative Dentistry, Affiliated Hospital of Stomatology, Medical College, Zhejiang University, Hangzhou, People’s Republic of China; 2Department of Oral Implantology and Prosthetic Dentistry, Academic Centre for Dentistry Amsterdam (ACTA), VU University Amsterdam and University of Amsterdam, MOVE Research Institute Amsterdam, Amsterdam, the NetherlandsBackground: To evaluate the respective or combinatory efficacy of locally delivered 2% minocycline (MO) and scaling and root planning (SRP) by assessing both clinical parameters and the loads of four main periodontal pathogens in treating chronic periodontitis (CP).Methods: Seventy adults with CP were randomly assigned to the three treatment groups: 1)SRP alone; 2) MO alone; and 3) combinatory use of SRP and MO (SRP + MO). Before and 7 days after the treatments, we evaluated both clinical parameters (pocket depth [PD] and sulcus bleeding index [SBI]) and the gene load of four main periodontal pathogens (Aggregatibacter actinomycetemcomitans [Aa], Fusobacterium nucleatum [Fn], Porphyromonas gingivalis [Pg], and Prevotella intermedia [Pi]).Results: The bacterial prevalence per patient was Aa, 31.25%; Fn, 100%; Pg, 95.31%; and Pi,98.44%. Seven days after treatments, the three treatments could significantly reduce both PD and SBI, but not detection frequencies of the four pathogens. For PD, the reduction efficacy ofSRP + MOwas significantly higher than that of both MO and SRP. Only Pg responded significantly to SRP. Pg and Fn could be significantly reduced in the presence of MO. OnlySRP + MObut not the respective showed a significant reduction effect on the gene load of Pi. The reduction of PD significantly correlated with the gene load of Pi (r=0.26; P=0.042) but not of the other bacteria.Conclusion: SRP and MO could reduce the load of Pi in an interdependent pattern, which correlated with symptomatic improvements of CP.Keywords: chronic periodontitis, minocycline, scaling and root planning, pocket depth, sulcus bleeding index, Prevotella intermedia

Biomimetic calcium phosphate coatings have been developed for bone regeneration and repair because of their biocompatibility, osteoconductivity, and easy preparation. They can be rendered osteoinductive by incorporating an osteogenic agent, such as bone morphogenetic protein 2 (BMP-2), into the crystalline lattice work in physiological situations. The biomimetic calcium phosphate coating enables a controlled, slow and local release of BMP-2 when it undergoes cell mediated coating degradation induced by multinuclear cells, such as osteoclasts and foreign body giant cells, which mimics a physiologically similar release mode, to achieve sustained ectopic or orthotopic bone formation. Therefore, biomimetic calcium phosphate coatings are considered to be a promising delivery vehicle for osteogenic agents. In this review, we present an overview of biomimetic calcium phosphate coatings including their preparation techniques, physico-chemical properties, potential as drug carrier, and their pre-clinical application both in ectopic and orthotopic animal models. We briefly review some features of hydroxyapatite coatings and their clinical applications to gain insight into the clinical applications of biomimetic calcium phosphate coatings in the near future.

ObjectivesThe first purpose of this study was to analyze the correlation between bone volume fraction (BV/TV) and calibrated radiographic bone density Hounsfield units (HU) in human jaws, derived from micro-CT and multislice computed tomography (MSCT), respectively. The second aim was to assess the accuracy of cone beam computed tomography (CBCT) in evaluating trabecular bone density and microstructure using MSCT and micro-CT, respectively, as reference gold standards.Material and methodsTwenty partially edentulous human mandibular cadavers were scanned by three types of CT modalities: MSCT (Philips, Best, the Netherlands), CBCT (3D Accuitomo 170, J Morita, Kyoto, Japan), and micro-CT (SkyScan 1173, Kontich, Belgium). Image analysis was performed using Amira (v4.1, Visage Imaging Inc., Carlsbad, CA, USA), 3Diagnosis (v5.3.1, 3diemme, Cantu, Italy), Geomagic (studio® 2012, Morrisville, NC, USA), and CTAn (v1.11, SkyScan). MSCT, CBCT, and micro-CT scans of each mandible were matched to select the exact region of interest (ROI). MSCT HU, micro-CT BV/TV, and CBCT gray value and bone volume fraction of each ROI were derived. Statistical analysis was performed to assess the correlations between corresponding measurement parameters.ResultsStrong correlations were observed between CBCT and MSCT density (r = 0.89) and between CBCT and micro-CT BV/TV measurements (r = 0.82). Excellent correlation was observed between MSCT HU and micro-CT BV/TV (r = 0.91). However, significant differences were found between all comparisons pairs (P < 0.001) except for mean measurement between CBCT BV/TV and micro-CT BV/TV (P = 0.147).ConclusionsAn excellent correlation exists between bone volume fraction and bone density as assessed on micro-CT and MSCT, respectively. This suggests that bone density measurements could be used to estimate bone microstructural parameters. A strong correlation also was found between CBCT gray values and BV/TV and their gold standards, suggesting the potential of this modality in bone quality assessment at implant site.

Je bent wat je eet. Wanneer men dit gezegde intikt in Google, verschijnen er talloze resultaten van sites die zich bezighouden met gezondheidsbevordering. Voeding in relatie tot gezondheid staat, terecht, enorm in de belangstelling. Onze evolutionaire ontwikkeling heeft via een eindeloze route van kleine aanpassingen geleid tot het best werkbare systeem in de gegeven omstandigheden. Gedurende het overgrote deel van de geschiedenis van de mensheid gingen de veranderingen van de natuurlijke omgeving uiterst langzaam. Hierin is een versnelling opgetreden die in gang werd gezet met de introductie van de landbouw en die is geëxplodeerd sinds de industriële revolutie. Het optreden van diverse welvaartsziekten wordt geassocieerd met de enorme veranderingen in ons voedselaanbod en de mismatch met hoe wij evolutionair zijn ontwikkeld. Recente wetenschappelijke ontwikkelingen geven ons een beter inzicht in de samenhang tussen voeding en ons immuunsysteem, celmetabolisme, wondgenezing en andere fundamentele biologische processen en de verstoring daarvan. Het is verstandig om ons huidige, veelal industriële, voedingsaanbod te heroverwegen indachtig de achtergrond van onze evolutie.

Objectives: This study identified potential general influencing factors for a mathematical prediction of implant stability quotient (ISQ) values in clinical practice. Methods: We collected the ISQ values of 557 implants from 2 different brands (SICace and Osstem) placed by 2 surgeons in 336 patients. Surgeon 1 placed 329 SICace implants, and surgeon 2 placed 113 SICace implants and 115 Osstem implants. ISQ measurements were taken at T1 (immediately after implant placement) and T2 (before dental restoration). A multivariate linear regression model was used to analyze the influence of the following 11 candidate factors for stability prediction: sex, age, maxillary/mandibular location, bone type, immediate/delayed implantation, bone grafting, insertion torque, I-stage or II-stage healing pattern, implant diameter, implant length and T1-T2 time interval. Results: The need for bone grafting as a predictor significantly influenced ISQ values in all three groups at T1 (weight coefficients ranging from -4 to -5). In contrast, implant diameter consistently influenced the ISQ values in all three groups at T2 (weight coefficients ranging from 3.4 to 4.2). Other factors, such as sex, age, I/II-stage implantation and bone type, did not significantly influence ISQ values at T2, and implant length did not significantly influence ISQ values at T1 or T2. Conclusions: These findings provide a rational basis for mathematical models to quantitatively predict the ISQ values of implants in clinical practice.

(1) Background: We tested the hypothesis that hyaluronic acid (HA) can significantly promote the osteogenic potential of BMP-2/ACS (absorbable collagen sponge), an efficacious product to heal large oral bone defects, thereby allowing its use at lower dosages and, thus, reducing its side-effects due to the unphysiologically-high doses of BMP-2; (2) Methods: In a subcutaneous bone induction model in rats, we first sorted out the optimal HA-polymer size and concentration with micro CT. Thereafter, we histomorphometrically quantified the effect of HA on new bone formation, total construct volume, and densities of blood vessels and macrophages in ACS with 5, 10, and 20 μg of BMP-2; (3) Results: The screening experiments revealed that the 100 µg/mL HA polymer of 48 kDa molecular weight could yield the highest new bone formation. Eighteen days post-surgery, HA could significantly enhance the total volume of newly-formed bone by approximately 100%, and also the total construct volume in the 10 μg BMP-2 group. HA could also significantly enhance the numerical area density of blood vessels in 5 μg BMP-2 and 10 μg BMP-2 groups. HA did not influence the numerical density of macrophages; and (4) Conclusions: An optimal combined administration of HA could significantly promote osteogenic and angiogenic activity of BMP-2/ACS, thus potentially minimizing its potential side-effects.

Objective: To assess implant survival rates and peri-implant bone loss of 2 titanium-zirconium implants supporting maxillary overdentures at 1 year of loading.Material and Methods: Twenty maxillary edentulous patients (5 women and 15 men) being dissatisfied with their complete dentures were included. In total, 40 diameter-reduced titanium-zirconium implants were placed in the anterior maxilla. Local guided bone regeneration (GBR) was allowed if the treatment did not compromise implant stability. Following 3 to 5 months of healing, implant-supported overdentures were inserted on two ball anchors. Implants and overdentures were assessed at 1, 2, 4, and 8 weeks after implant insertion and 2, 4, and 12 months after insertion of overdentures (baseline). Standardized radiographs were taken at implant loading and 1 year. Implant survival rates and bone loss were the primary outcomes.Results: Nineteen patients (1 dropout) with 38 implants were evaluated at a mean follow-up of 1.1 years (range 1.0-1.7 years). One implant failed resulting in an implant survival rate of 97.3%. There was a significant peri-implant bone loss of the implants at 1 year of function (mean, 0.7 mm, SD = 1.1 mm; median: 0.48 mm, IQR = 0.56 mm).Conclusions: There was a high 1-year implant survival rate for edentulous patients receiving 2 maxillary implants and ball anchors as overdenture support. However, several implants exhibited an increased amount of bone loss of more than 2 mm. Overdentures supported by 2 maxillary implants should thus be used with caution as minimally invasive treatment for specific patients encountering problems with their upper dentures until more long-term data is available.

Aim: To elucidate whether mitochondrial dysfunction contributes to aggravated periodontitis in diabetes. Materials and Methods: Sixty-four wistar rats were randomly assigned into four groups: control, periodontitis, diabetes, and diabetic periodontitis. Two weeks after induction of diabetes, periodontitis was induced by silk ligation for 2 weeks and thereafter evaluated by assessing alveolar bone loss and apoptosis of periodontium cells. Mitochondrial oxidative stress was detected by MitoSOX staining. Mitochondrial function was determined by measuring ATP production, and by assessing mitochondrial DNA copy number, activities of electron transport chain complexes, and biogenesis with real-time PCR.Results: Significantly severer bone loss, enhanced periodontium cell apoptosis, and mitochondrial oxidative stress were found in the rats with diabetic periodontitis than the others. Furthermore, diabetic rats with periodontitis presented severer mitochondrial dysfunction than lean rats with periodontitis, as reflected by compromised ATP production, decreased mitochondrial DNA copy number, reduced gene expression of electron transport chain complex I subunits, and impaired mitochondrial biogenesis (p Conclusions: Mitochondrial dysfunction was positive correlated to aggravated periodontitis in diabetes and might represent a therapeutic target for diabetic periodontitis.

Objectives/Aims: To describe the protocol of a prospective cohort study designed to answer the question: ‘Is sleep bruxism a risk factor for (peri-)implant complications?’. Materials and Methods: Our study is a single-centre, double-blind, prospective cohort study with a follow-up time of 2 years. Ninety-eight participants fulfilling inclusion criteria (planned treatment with implant-supported fixed suprastructure(s) and age 18 years or older) will be included. Sleep bruxism will be monitored at several time points as masticatory muscle activity during sleep by means of a portable single-channel electromyographic device. Our main outcomes are biological complications (i.e., related to peri-implant bleeding, probing depth, marginal bone height, quality of submucosal biofilm and loss of osseointegration) and technical complications (i.e., suprastructure, abutment, implant body or other). Results: The study is currently ongoing, and data are being gathered. Discussion: The results of this prospective cohort study will provide important information for clinicians treating bruxing patients with dental implants. Furthermore, it will contribute to the body of evidence related to the behaviour of dental implants and their complications under conditions of high mechanical loadings that result from sleep bruxism activity. Conclusion: The protocol of a prospective cohort study designed to investigate possible associations between sleep bruxism and (peri-) implant complications was presented.

In 1973 schreef Francois Duret zijn proefschrift over intraoraal scannen en hoe dit in de tandheelkunde kon worden gebruikt. Al begin jaren tachtig werd de cerec1geïntroduceerd: de eerste mondscanner, in een workflow gecombineerd met een freesstation. Toch heeft het tot 2012 geduurd voordat de intraorale (io) scanners echt in de tandheelkunde begonnen door te dringen. De digitale technologieën geven ons de mogelijkheid onze patiënten op een andere manier te begeleiden en te adviseren. Ook kunnen we in de digitale workflow een totale benadering van de behandeling in een digitale omgeving plannen. De geplande behandeling kan dan via gefreesde en 3D-geprinte sjablonen worden overgedragen op de patiënt zelf, waardoor behandelingen sneller en meer kosteneffectief kunnen worden uitgevoerd. Het invoeren van digitale technologieën op grote schaal heeft echter nog wel wat voeten in de aarde. Het waarborgen van de privacy van de patiënt op de digitale snelweg en in de cloud is niet eenvoudig te regelen.

Intraoraal scannen is al sinds de jaren tachtig volop in ontwikkeling. De indicatiegebieden zijn met de verbeterde accuratesse van de nieuwste generatie scanners sterk verbreed. Wanneer wordt gekeken naar het functioneren van de digitale gebitsweergave in vergelijking met de conventionele gebitsafdruk, moet niet alleen naar (theoretische) accuratesse worden gekeken maar ook naar efficiency en resultaten van de gehele klinische workflow. Om de nauwkeurigheid te verbeteren is het raadzaam – waar mogelijk – partiële digitale afdrukken te maken in plaats van de volledige kaak te scannen. Behalve voor het vervaardigen van restauraties, zullen scanners in de nabije toekomst ook steeds vaker als diagnostisch middel worden toegepast.

Cellular adhesion is essential for successful integration of dental implants. Rapid soft tissue integration is important to create a seal around the implant and prevent infections, which commonly cause implant failure and can result in bone loss. In addition, soft tissue management is important to obtain good dental aesthetics. We previously demonstrated that the salivary peptide histatin 1 (Hst1) causes a more than 2-fold increase in the ability of human adherent cells to attach and spread on a glass surface. Cells treated with Hst1 attached more rapidly and firmly to the substrate and to each other. In the current study, we examine the potential application of Hst1 for promotion of dental implant integration. Our results show that Hst1 enhances the attachment and spreading of soft tissue cell types (oral epithelial cells and fibroblasts) to titanium (Ti) and hydroxyapatite (HAP), biomaterials that have found wide applications as implant material in dentistry and orthopedics. For improved visualization of cell adhesion to Ti, we developed a novel technique that uses sputtering to deposit a thin, transparent layer of Ti onto glass slides. This approach allows detailed, high-resolution analysis of cell adherence to Ti in real time. Furthermore, our results suggest that Hst1 has no negative effects on cell survival. Given its natural occurrence in the oral cavity, Hst1 could be an attractive agent for clinical application. Importantly, even though Hst1 is specific for saliva of humans and higher primates, it stimulated the attachment and spreading of canine cells, paving the way for preclinical studies in canine models.

Absorbed collagen sponge (ACS)/bone morphogenetic protein-2 (BMP-2) are widely used in clinical practise for bone regeneration. However, the application of this product was found to be associated with a significant pro-inflammatory response, particularly in the early phase after implantation. This study aimed to clarify if the pro-inflammatory activities, associated with BMP-2 added to ACS, were related to the physical state of the carrier itself, i.e., a wet or a highly dehydrated state of the ACS, to the local degree of vascularisation and/or to local biomechanical factors. ACS (0.8 cm diameter)/BMP-2 were implanted subcutaneously in the back of 12 eight-week-old Sprague Dawley rats. Two days after surgery, the implanted materials were retrieved and analysed histologically and histomorphometrically. The acute inflammatory response following implantation of ACS was dependent of neither the presence or absence of BMP-2 nor the degree of vascularization in the surrounding tissue nor the hydration state (wet versus dry) of the ACS material at the time of implantation. Differential micro biomechanical factors operating at the implantation site appeared to have an influence on the thickness of inflammation. We conclude that the degree of the early inflammatory response of the ACS/BMP-2 may be associated with the physical and chemical properties of the carrier material itself.

Peri-implantitis is een infectieuze ziekte waarbij het sonderen van een implantaat gepaard gaat met bloeding, pus, suppuratie of een combinatie van deze factoren, samen met röntgenologisch aantoonbaar botverlies.Het is de vraag of de huidige implantaten met een ruwe oppervlaktestructuur tot de hals van het implantaat nog steeds de implantaten van eerste keus zijn. Bij het ontwikkelen van een periimplantitis zijn mondhygiëne, een voorgeschiedenis van parodontitis of eerder doorgemaakte peri-implantitis en roken oorzakelijke factoren bij het ontstaan hiervan. Ook is duidelijk dat een peri-implantitisbehandeling chirurgisch moet worden uitgevoerd, waarbij het doel verwijderingvan de biofilm op het implantaat en in de meeste gevallen pocketdieptereductie is.6 Het streven daarbij moet zijn om zo veel mogelijk aangehechte gingiva te behouden. Hoewel er een redelijkeconsensus bestaat over de manier waarop deze chirurgische behandeling moet plaatsvinden, zijn er op detailniveau verschillende stromingen. Nader onderzoek zal moeten uitwijzen wat de optimale chirurgische behandeling bij een peri-implantitis is.

Er zijn grofweg drie implantaatconnecties op te markt: butt joint- conische, en gebevelde schouderconnectie. Bij kroon- en brugwerk op implantaten zorgt het emergence profile ervoor dat van een ronde implantaatconnectie een natuurlijke tandvorm wordt gecreëerd. Het emergence profile kan sonderen soms bemoeilijken. Sowieso moet bij het sonderen van implantaten duidelijk het verschil met een natuurlijk element in acht worden genomen. Om prothetische en hygiënische redenen kan ervoor gekozen worden technieken als premolarisatie en het verblokken van kronen toe te passen, zodat prettig te reinigen interdentale ruimtes overblijven. Ook bij overkappingsprotheses is het aan te raden om rekening te houden met de vormgeving van de ruimte naast de implantaten, zodat de ragergeleiding ontstaat.

Objectives: Biphasic calcium phosphate (BCP) is frequently used as bone substitute and often needs to be combined with autologous bone to gain an osteoinductive property for guided bone regeneration in implant dentistry. Given the limitations of using autologous bone, bone morphogenetic protein-2 (BMP2)-coprecipitated, layer-by-layer assembled biomimetic calcium phosphate particles (BMP2-cop.BioCaP) have been developed as a potential osteoinducer. In this study, we hypothesized that BMP2-cop.BioCaP could introduce osteoinductivity to BCP and so could function as effectively as autologous bone for the repair of a critical-sized bone defect. Materials and methods: We prepared BMP2-cop.BioCaP and monitored the loading and release kinetics of BMP2 from it in vitro. Seven groups (n = 6 animals/group) were established: (i) Empty defect; (ii) BCP; (iii) BCP mixed with biomimetic calcium phosphate particles (BioCaP); (iv) BCP mixed with BMP2-cop.BioCaP; (v) BioCaP; (vi) BMP2-cop.BioCaP; (vii) BCP mixed with autologous bone. They were implanted into 8-mm-diameter rat cranial critical-sized bone defects for an in vivo evaluation. Autologous bone served as a positive control. The osteoinductive efficacy and degradability of materials were evaluated using micro-CT, histology and histomorphometry. Results: The combined application of BCP and BMP2-cop.BioCaP resulted in significantly more new bone formation than BCP alone. The osteoinductive efficacy of BMP2-cop.BioCaP was comparable to the golden standard use of autologous bone. Compared with BCP alone, significantly more BCP degradation was found when mixed with BMP2-cop.BioCaP. Conclusion: The combination of BCP and BMP2-cop.BioCaP showed a promising potential for guided bone regeneration clinically in the future.

Objective: The objective of this study was to evaluate crestal bone changes around bone- and tissue-level implants related to initial mucosal thickness.Materials and methods: Patients received at least 2 implants: one with the prosthetic abutment connection at the crestal bone level (MC) and one with the prosthetic abutment connection at 2.5 mm supra crestal (LC). Flap thickness measurements were taken using a periodontal probe after raising the buccal flap. Patients were divided into 2 groups according to the mucosal thickness-Group A (thickness, ≤2 mm) and Group B (thickness, >2 mm).Results: Our study included 33 patients and 78 implants. Each patient received at least 1 implant of each type: Group A (MC), 17 implants, with a mean bone change of -0.6 ± 0.5 mm; Group B (MC), 20 with a mean bone change of -0.2 ± 0.4 mm; Group A (LC), 15 with a mean bone change of -0.1 ± 0.5 mm; and Group B (LC), 22 with a mean bone change of -0.2 ± 0.4 mm. A paired-samples t-test for groups A (MC) and B (MC) yielded a statistically significant difference (P = 0.003); there was no statistically significant difference for groups A (LC) and B (LC) (P = 0.518).Conclusion: If the initial mucosal thickness surrounding bone-level implants is more than 2 mm, there is significantly less crestal bone change compared with bone-level implants placed in initial mucosal thicknesses of 2 mm or less. This difference is not statistically significant when tissue-level implants are used and the implant-abutment connection is 2.5 mm above the crestal bone level.

Most materials used clinically for filling critical-sized bone defects (CSBD), such as deproteinized bovine bone (DBB), lack osteoinductivity so that their therapeutic effects are far from satisfactory. The effect of bone morphogenic protein 2 (BMP2)-coprecipitated biomimetic calcium phosphate granules (BMP2-cop.BioCaP) on osteoinduction of DBB graft(s) during CSBD healing is still unknown. We investigated whether BMP2-cop.BioCaP affects the osteoinductivity of DBB, bone formation, and foreign body reaction during CSBD healing. DBB + BMP2-cop.BioCaP, DBB, DBB + BMP2, DBB + BioCaP, and autologous bone grafts were implanted in the CSBD of sheep. Bone formation, DBB/BioCaP degradability, foreign body reaction, and osteoinductivity of DBB were analyzed histologically and histomorphometrically at week 4 and 8. Combination of BMP2-cop.BioCaP and DBB healed CSBD as effectively as autologous bone grafts. About 95% of the BMP2-cop.BioCaP had been degraded and replaced by new bone at week 8 in the DBB + BMP2-cop.BioCaP-group. Foreign body reaction was reduced in the DBB + BMP2-cop.BioCaP-group compared to the other groups. The independent use of the BMP2-cop.BioCaP did not achieve a satisfactory bone repair. In conclusion, the BMP2-cop.BioCaP showed good degradability and biocompatibility, and enhanced osteoinductivity of DBB during CSBD healing in sheep, suggesting BMP2-cop.BioCaP as a potential osteoinducer to enhance the therapeutic effects of the graft materials in clinic.

Volume 10 of the ITI Treatment Guide series starts out with the most recent statements and recommendations of the 5th ITI Consensus Conference, followed by a detailed protocol for the evaluation and treatment planning of patients with esthetic demands requiring single-tooth replacement with a dental implant. This volume of the ITI Treatment Guide series provides a comprehensive, evidence-based approach to single-tooth replacement in the esthetic zone, from consultation to follow-up, with a focus on current treatment modalities and on the materials that present-day implant dentistry has to offer.

Objective: To determine implant survival and prosthodontic maintenance of implant-assisted mandibular removable partial dentures in a multicentre prospective study up to 10 years. Materials and methods: Forty-eight participants with mandibular distal extension partial dentures were selected. A control group of 12 New Zealand participants had new conventional mandibular partial dentures made. Three test groups of 36 participants in New Zealand (n = 12), the Netherlands (n = 12) and Colombia (n = 12) had bilateral distal implants placed. Surgical and prosthodontic outcomes were documented with only healing caps placed (Stage 1) and with an attachment system (Stage 2). Results: No implants failed after 3 years. Four late implant failures in three participants occurred in New Zealand (two unilateral implant failures after 5 and 8 years and two bilateral implant failures in the same participant after 6 and 10 years); two unilateral late implant failures occurred in the Netherlands and no late failures in Colombia. Implant survival rate was 92% by 10 years. Resonance frequency measurements were taken at surgery implant stability quotient (ISQ) 62.44 ± 7.46; range 40 – 79), baseline (ISQ 63.22 ± 6.17; range 50 – 74) and after 3 years (ISQ 66.38 ± 6.77; range 55 – 83). In New Zealand and Colombia, measured crestal bone levels were 2.03 ± 0.71 mm and 2.20 ± 0.81 mm, respectively, at baseline and 3 years. For Stage I, principal prosthodontic maintenance issues were loose healing caps among 10 New Zealand participants, four Colombian participants and one Netherlands participant. For Stage 2, matrix activation and overdenture puncture fractures resulted in 41 events (25 participants) in New Zealand over 10 years, whilst over 3 years, there were 14 events in nine Colombian participants and six events in five Netherlands participants. Conclusion: This clinical multicentre research complements previous case reports, case series, retrospective and prospective studies on the notion of implant-assisted removable partial dentures for partially edentulous patients. Late implant failures and increased prosthodontic maintenance when an attachment system is used identify the need for further research, including more robust statistical analyses.

The purpose of this study was to develop a new method for a peri-implantitis model in beagle dogs in which a stainless steel ligature (SSL) was used independently. A total of 36 Straumann dental implants were placed in six beagle dogs 1 month after all mandibular premolars were extracted. After 3 months, SSLs were placed in a submarginal position on the implants to induce peri-implantitis and were not replaced during the 12-week tissue breakdown period. Inducing peri-implantitis in the beagles with an SSL is a rapid, effective, and simple method.

Background Temporomandibular Disorders (TMD) may be characterized by pain and restricted jaw movements. In the absence of somatic factors in the temporomandibular joint, mainly myogenous, psychobiological, and psychosocial factors may be involved in the aetiology of myogenous TMD. An occlusal appliance (splint) is commonly used as a basic therapy of the dental practice. Alternatively, a type of physiotherapy which includes, apart from massage of sore muscles, aspects of cognitive-behavioural therapy might be a basic therapy for myogenous TMD. Treatment outcome of physiotherapy (Ph-Tx) was evaluated in comparison to that of splint therapy (Sp-Tx), using the index Treatment Duration Control (TDC) that enabled a randomized controlled trial with, comparable to clinical care, therapy-and-patient-specific treatment durations. Methods Seventy-two patients were randomly assigned to either Ph-Tx or Sp-Tx, with an intended treatment duration between 10 and 21 or 12 and 30 weeks respectively. Using TDC, the clinician controlled treatment duration and the number of visits needed. A blinded assessor recorded anamnestic and clinical data to determine TDC-values following treatment and a 1-year follow-up, yielding success rate (SR) and effectiveness (mean TDC) as treatment outcomes. Cohen’s d, was determined for pain intensity. Overall SR for stepped-care was assessed in a theoretical model, i.e. a second of the two studied therapies was applied if the first treatment was unsuccessful, and the effect of therapy sequence and difference in success rates was examined. Results SR and effectiveness were similar for Ph-Tx and Sp-Tx (long-term SR: 51–60%; TDC: −0.512– −0.575). Cohen’s d was 0.86 (Ph-Tx) and 1.39 (Sp-Tx). Treatment duration was shorter for Ph-Tx (on average 10.4 weeks less; p

Periodontal tissue regeneration is the ultimate goal of the treatment for periodontitis-affected teeth. The success of regenerative modalities relies heavily on the utilization of appropriate biomaterials with specific properties. Poly (lactic-co-glycolic acid) (PLGA), a synthetic aliphatic polyester, has been actively investigated for periodontal therapy due to its favorable mechanical properties, tunable degradation rates, and high biocompatibility. Despite the attractive characteristics, certain constraints associated with PLGA, in terms of its hydrophobicity and limited bioactivity, have led to the introduction of modification strategies that aimed to improve the biological performance of the polymer. Here, we summarize the features of the polymer and update views on progress of its applications as barrier membranes, bone grafts, and drug delivery carriers, which indicate that PLGA can be a good candidate material in the field of periodontal regenerative medicine.

ObjectivesThe aim of this in vitro pilot investigation is to assess the accuracy of the preemptive individually fabricated root analogue implant (RAI) based on three-dimensional (3D) root surface models obtained from a cone beam computed tomography (CBCT) scan, computer-aided designing (CAD), and computer-aided manufacturing (CAM) technology and to measure the discrepancy in congruence with the alveolar socket subsequent to placement of the RAI.Materials and methodsEleven single-rooted teeth from nine human cadaver mandibles were scanned with the 3D Accuitomo 170 CBCT system. The 3D surface reconstructions of the teeth acquired from the CBCT scans were used as input for fabrication of the RAIs in titanium using rapid manufacturing technology. The teeth were then carefully extracted. The teeth and RAIs were consequently optically scanned. The mandibles with the empty extraction sockets were scanned with CBCT using identical settings to the first scan. Finally, the preemptively made RAIs were implanted into their respective sockets, and the mandibles were again scanned with CBCT using the same scan settings as previous scans. All 3D surface reconstructions (CBCT 3D surface models and optical scan 3D models) were saved for further analysis. 3D models of original teeth and optical scans of the RAIs were superimposed onto each other; differences were quantified as root mean square (RMS) and Hausdorff surface distance. To obtain an estimate of the fit (congruence) of the RAIs in their respective sockets, the volumetric data sets of the sockets were compared with those of the root part of RAIs congruent with the sockets.ResultsSuperimposed surfaces of the RAIs and the original tooth reveal discrepancy for RMS, volumetric geometry, and surface area varying from 0.08 mm to 0.35 mm, 0.1% to 7.9%, and 1.1% to 3.8%, respectively. Comparing volume differences of the alveolus with the socket corresponding part of the RAI resulted in every case the volume of the socket being greater than the root part of the RAI ranging from 0.6% to 5.9% volume difference.ConclusionThe preemptive CAD/CAM-based RAI technique might offer promising features for immediate implant placement. However, due to the lack of prospective clinical data, further research is needed to fine-tune and evaluate this technique.

Successful dental implant rehabilitation requires accurate preoperative planning of the surgical intervention based on prosthodontic considerations and validated treatment methods. The introduction and widespread use of cross-sectional imaging in implant dentistry using cone beam computed tomography (CBCT) over the last decade has enabled clinicians to diagnose and evaluate the jaws in three dimensions before and after insertion of dental implants, thus replacing computed tomography (CT) as the standard of care. Furthermore, computer-guided implant surgery uses data from cross-sectional imaging derived from CBCT scans on a routine basis. Considering rapid changes in science and clinical practice, the first two systematic reviews in this group by Bornstein et al and Tahmaseb et al have centered their focused questions on these topics.

Objectives. The primary objective of this clinical study was to assess the patients' perception of the difference between an analogue impression approach on the one hand and an intra-oral scan (IO scan) on the other when restoring implants in the non-aesthetic zone. A second objective was to analyse the difference in time needed to perform these two procedures. Materials and methods. Thirty consecutive patients who had received 41 implants (Straumann tissue level) in the non-aesthetic zone in an implant-based referral practice setting in the Netherlands. As they were to receive crown and or bridge work on the implants, in one session, the final impressions were taken with both an analogue technique and with an intraoral scan. Patients were also asked if, directly after the treatment was carried out, they would be prepared to fill out a questionnaire on their perception of both techniques. The time involved following these two procedures was also recorded. Results. The preparatory activities of the treatment, the taste of the impression material and the overall preference of the patients were significantly in favour of the IO scan. The bite registration, the scan head and gag reflex positively tended to the IO scan, but none of these effects were significant. The overall time involved with the IO scan was more negatively perceived than the analogue impression. Overall less time was involved when following the analogue impression technique than with the IO scan. Conclusions. The overall preference of the patients in our sample is significantly in favour of the approach using the IO scan. This preference relates mainly to the differences between the compared approaches with respect to taste effects and their preparatory activities. The patients did perceive the duration of IO scan more negatively than the analogue impression approach. Keywords: digital dentistry; intraoral scanning; oral Implants; patient satisfaction; prosthetic dentistry

ObjectiveThis study aimed to classify peri-implant bone defects (PIBDs) on the basis of their radiographic appearance in a cohort of patients with lower implant-supported overdentures.Materials and methodsEighty-three patients with lower implant-supported overdentures were recruited to participate in the study, which was approved by the ethics committee of Ignatius Teaching Hospital. Details about the patients' smoking habits were recorded. The participants had a total of 224 implants involving 3214 implant sites. The mean observation time of the subjects was 10.7 years. Panoramic radiographs of ll sites were evaluated in duplicate (first evaluation [t1], second evaluation [t2]) during 2 weeks by one experienced observer. PIBDs were classified into the following types: saucer-shaped, wedge-shaped, flat, undercut, and slit-like bone defects. Intra-examiner agreement was tested using crosstabs and Cohen's kappa coefficient. The association of PIBD type with gender, time after implant placement, smoking, and treatment strategy was investigated using multivariate test of independence on the basis of spatial signs.ResultsIntra-observer reliability was moderate (κ = 0.51). Saucer-shaped defects were the most frequent (42.8% [t1] and 44.6% [t2]), followed by wedge-shaped (26.0% [t1] and 27.4% [t2]), flat (10.7% [t2] and 17.7% [t1]), undercut (8.8% [t1] and 11.9% [t2]), and finally slit-like defects (4.7% [t1] and 5.4% [t2]). Peri-implant bone defects morphology was significantly associated with gender, smoking, and treatment strategy.ConclusionThe morphology of PIBDs can be classified into five meaningful classes, as opposed to the two described in the literature.

Large-size bone defects can severely compromise both aesthetics and musculoskeletal functions. Adipose-derived stem cells (ASCs)-based bone tissue engineering has recently become a promising treatment strategy for the above situation. As robust osteoinductive cytokines, bone morphogenetic proteins (BMPs) are commonly used to promote the osteogenesis of ASCs. In this process, BMP signaling plays a pivotal role. However, it remains ambiguous how the pleiotrophic BMPs are involved in the commitment of ASCs along osteogenesis instead of other lineages, such as adipogenesis. BMP receptor type-IB, extracellular signal-regulated kinase, and Wnt5a appear to be the main switches controlling the in vitro osteogenic commitment of ASCs. Tumor necrosis factor-alpha, an acute inflammatory cytokine, is reported to play an important role in mediating osteogenic commitment of ASCs in vivo. In addition, various active agents and methods have been used to enhance and accelerate the osteogenesis of ASCs through promoting BMP signaling. In this review, we summarize the current knowledge on the roles of BMPs and their signaling in the osteogenesis of ASCs in vitro and in vivo.

ObjectivesGraft resorption remains a major disadvantage of the various employed materials in maxillary sinus augmentation. Our aim was to assess the percentage of graft volume reduction in deproteinized bovine bone (DBB) using cone beam computed tomography (CBCT).Materials and MethodsA retrospective analysis of 29 augmented sinuses in 19 patients was conducted. The graft material was either DBB alone or DBB mixed with autologous bone chips (80% DBB/20% bone chips). CBCT scans of the augmented sinuses were obtained pre- and post-operatively up to 2-year follow-up.ResultsIn total, 55 dental implants were placed in the posterior maxillary region following sinus augmentation. The mean height of the alveolar ridge pre-operative was 2.7 ± 1.2 mm and post-operative was 14.13 ± 4.6 mm. The mean percentages of alveolar ridge height reduction were 18.58% (SD14.23%) and 27.62% (SD12.70%), and the mean percentages of graft volume reduction were 19.30% (SD9.19%) and 19.85% (SD9.61%) for DBB and DBB + bone chips, respectively.ConclusionsThe results indicate that DBB graft volume resorption is approximately (20 ± 10%) following 2-year follow-up. CBCT is a useful radiographic tool to follow-up changes in sinus graft volumes.

ObjectiveTo compare the levels of patient satisfaction with either conventional mandibular bilateral distal extension partial dentures or those assisted by bilateral distal implants.Materials and methodsForty-eight participants who were dissatisfied with their existing conventional mandibular distal extension dentures opposing complete maxillary dentures were selected for a multicentre prospective study in New Zealand, Colombia and the Netherlands. A control group of 12 participants in New Zealand received conventional mandibular partial dentures. Three test groups involving 36 participants in New Zealand (12), Colombia (12) and the Netherlands (12) received bilateral distal implants in the second molar regions. After conventional loading, the test group participants initially had healing caps placed on the distal implants providing support only, followed after approximately 6 months by ball abutments (retentive anchors) for support and retention. Patient outcomes were determined with questionnaires completed at specific stages of the study for up to 3 years.ResultsVisual analogue scale, Likert and oral health impact questionnaires before and after treatment indicated improved results. There were significantly improved parameters of overall satisfaction, stability, chewing and appearance after 3 years (P < 0.05). There were also improvements on stability, chewing and overall satisfaction. Speech also improved, but not significantly. Ball abutments (retentive anchors) on the distal implants, as opposed to healing caps improved patient satisfaction for stability, chewing and overall satisfaction. Changing to ball abutments (retentive anchors) revealed significant improvement by participant response when evaluating parameters of stability, chewing and overall satisfaction (P < 0.05).ConclusionMandibular implant-assisted removable partial dentures are a preferable treatment option for patients with complaints about their conventional distal extension partial dentures.

OBJECTIVE: Aimed to evaluate the long-term clinical and radiographic outcomes of short implants supporting single crowns in the posterior regions.MATERIAL AND METHODS: A retrospective study design was adopted. The clinical and radiographic data of 231 short implants (intra-bony length ≤8 mm) supporting single crowns in 168 patients, were collected after 5-10 (mean 7.22) years' follow-up. Implant and prosthesis failures, peri-implant marginal bone loss, biological and technical complications were evaluated. The influence factors on implant failure were studied.RESULTS: In total 4 implants and 11 prostheses failed. The 10-year (5-year) cumulative survival rate was 98.3% (98.7%) for implant-based analysis and 97.6% (98.2%) for patient-based analysis. The short implants placed in type IV bone yielded more failures than in type I-III and presented a survival rate of 94.0%. The 10-year survival rate of the prostheses was 95.2%. The mean marginal bone loss between implant installation and the 10 years' follow-up visit was 0.63 ± 0.68 mm. The marginal bone loss between the first and 5th year was minimal (0.05 ± 0.10mm and not statistically significant). 18 (7.8%) implants were exposed to biological complications, whereas 29 (12.6%) implants were involved in technical complications.CONCLUSIONS: High survival rates for both the implants and the prostheses could be achieved after 5-10 years for short implants supporting single crowns, without severe marginal bone loss and complications. One may conclude that a single crown supported by a short implant is a predictable treatment modality. However, short implants in type IV bone sites should be applied with caution.

Purpose: The aim of this study was to investigate the influence of oral implant surface roughness on bacterial biofilm formation and antimicrobial treatment efficacy. Materials and Methods: Titanium disks with low-roughness pickled surfaces and with moderately rough sandblasted, acid-etched surfaces were used as substrata. Streptococcus mutans biofilms (1 and 3 days old) and Porphyromonas gingivalis biofilms (3 days old) were grown on the two types of substrata and then treated with 0.2% chlorhexidine. Biofilm viability was evaluated by a resazurin metabolism assay and by sonication-colony-forming unit counts. Results: Surface roughness had no influence on the amount of biofilm formation by S mutans or P gingivalis in this in vitro biofilm model. However, it strongly affected the treatment efficacy of chlorhexidine on the biofilms formed by both species. Higher roughness resulted in lower efficacy. Furthermore, treatment efficacy was significantly reduced in older biofilms. Conclusion: A moderately roughened surface did not enhance biofilm formation but reduced treatment efficacy of the biofilms. This finding indicates that efforts should be directed toward optimizing implant surface properties for effective antimicrobial treatment without compromising osseointegration.

Background Odontogenic myxoma is a benign, locally aggressive neoplasm of the jaws. Prevalence rates range between 0.5% and 17.7% of odontogenic tumours. There are few reports in the literature on this lesion in African populations, and therefore, this study aimed to report on odontogenic myxoma in a South African population over a 40-year period. Methods The clinical records and orthopantomograms of 29 histopathologically diagnosed odontogenic myxoma were retrospectively analysed. Details of age, gender, ethnic origin and clinical, histological as well as radiological features were recorded. Results The ages of patients ranged from 7 to 44 years with a mean of 21.3 years. The male-to-female ratio was 1:2.6 with the majority of patients being of mixed race and Africans. Clinically, 31% complained of pain while 58.6% had a history of swelling. The majority of odongenic myxomas (62.1%) were located in the mandible with the posterior region being most commonly affected. Multilocular lesions (69.2%) were more common and were significantly larger than unilocular lesions (P < 0.05). The outline of these tumours was mostly well-defined (84.6%) with different degrees of cortication. Only one tumour caused tooth resorption, while 20 cases (76.9%) caused tooth displacement. Six tumours expanded into the maxillary sinus, and 14 tumours caused expansion of the mandible. Conclusions Odontogenic myxomas have variable clinical, radiological and histological features. Most of these features in this population were similar to other populations. It is mandatory to use conventional radiographs along with histopathological examination to aid in arriving at an accurate diagnosis.

Objectives: The aim of this study was to introduce a new concept for computer-assisted template-guided placement of a custom 3D-designed/3D-printed implant with congruent custom 3D-designed/3D-printed surgical tooling and to test the feasibility and accuracy of this method in-vitro.Materials and methods: One partially edentulous human mandibular cadaver was scanned with a cone-beam computed tomography (CBCT) system and intra-oral scan system. The 3D data of this cadaver were imported in specialized software and used to analyse the region of a missing tooth. Based on the functional and anatomical parameters, an individual implant with congruent surgical tooling and surgical guided template was designed and 3D-printed. The guided osteotomy was performed, and the custom implant inserted. To evaluate the planned implant position in comparison with the placed implant position, the mandible with implant was scanned again with the CBCT system and software matching was applied to measure the accuracy of the procedure.Results: The angular deflection with the planned implant position was 0.40°. When comparing the 3D positions of the shoulder, there is a deviation of 0.72 mm resulting in an apical deviation of 0.72 mm.Conclusion: With the use of currently available technology, it is very well feasible to create in a virtual simulation a custom implant with congruent custom surgical tooling and to transfer this to a clinical setting. However, further research on multiple levels is needed to explore this novel approach.

Objective：To investigate the role of bone morphogenetic protein 2/7 heterodimer (BMP-2/7) in the osteogenesis of human adipose-derined stem cells (hASCs). Methods: hASCs were exposed to three different treatments in vitro: osteogenic medium with 150 μg/L BMP-2/7 (experimental group), osteogenic medium alone (OM group) and proliferation medium (PM group). After 1, 4 and 7 days of osteogenic induction, the amount of cellular DNA was measured to investigate the cytotoxicity. After 7 and 14 days, alkaline phosphatase (ALP) staining and quantification were performed to test the activity of ALP. After 21 and 28 days, the calcification deposition was determined by Alizarin Red S (ARS) staining and quantification. The expressions of the osteoblast-related genes were tested on days 1, 4, 7 and 14. In the in vivo study, 6 nude mice were used and 4 groups were set and implanted subcutaneously into the back of nude mice: (1) β-TCP scaffold only (scaffold control group); (2) β-TCP scaffold with hASCs cultured by PM in vitro for 1 week (PM control group); (3) β-TCP scaffold with hASCs cultured by OM in vitro for 1 week (OM control group); (4) β-TCP scaffold with hASCs cultured by OM with 150 μg/L BMP-2/7 in vitro for 1 week (test group). After 4 weeks of implantation, histological staining was performed to evaluate the in vivo osteogenesis of hASCs. Results: After induction for 1 day, there was no significant difference between the experimental group and the PM group on the cellular DNA content (P>0.05). After 4 days, the cellular DNA content increased under the stimulation of BMP-2/7 (P0.05). ALP activity was higher by the induction of BMP-2/7 than in OM alone and PM (P

The repair of infected bone defects is still challenging in the fields of orthopedics, oral implantology and maxillofacial surgery. In these cases, the self-healing capacity of bone tissue can be significantly compromised by the large size of bone defects and the potential/active bacterial activity. Infected bone defects are conventionally treated by a systemic/local administration of antibiotics to control infection and a subsequent implantation of bone grafts, such as autografts and allografts. However, these treatment options are time-consuming and usually yield less optimal efficacy. To approach these problems, novel biomaterials with both antibacterial and osteoinductive properties have been developed. The antibacterial property can be conferred by antibiotics and other novel antibacterial biomaterials, such as silver nanoparticles. Bone morphogenetic proteins are used to functionalize the biomaterials with a potent osteoinductive property. By manipulating the carrying modes and release kinetics, these biomaterials are optimized to maximize their antibacterial and osteoinductive functions with minimized cytotoxicity. The findings, in the past decade, have shown a very promising application potential of the novel biomaterials with the dual functions in treating infected bone defects. In this review, we will summarize the current knowledge of novel biomaterials with both antibacterial and osteoinductive properties.

Bone tissue engineering technique is a promising strategy to repair large-volume bone defects. In this study, we developed a 3-dimensional construct by combining icariin (a small-molecule Chinese medicine), allogeneic bone marrow-derived mesenchymal stem cells (BMSCs), and a siliceous mesostructured cellular foams-poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (SMC-PHBHHx) composite scaffold. We hypothesized that the slowly released icariin could significantly promote the efficacy of SMC-PHBHHx/allogeneic BMSCs for repairing critical-size bone defects in rats. In in vitro cellular experiments, icariin at optimal concentration (10−6 mol/L) could significantly upregulate the osteogenesis- and angiogenesis-related genes and proteins, such as Runx2, ALP, osteocalcin, vascular endothelial growth factors, and fibroblast growth factors, as well as the mineralization of BMSCs. Icariin that was adsorbed onto the SMC-PHBHHx scaffold showed a slow release profile within a 2-week monitoring span. Eight weeks after implantation in calvarial critical-size bone defects, the constructs with icariin were associated with significantly higher bone volume density, trabecular thickness, trabecular number, and significantly lower trabecular separation than the constructs without icariin. Histomorphometric analysis showed that icariin was also associated with a significantly higher density of newly formed blood vessels. These data suggested a promising application potential of the icariin/SMC-PHBHHx/allogeneic BMSCs constructs for repairing large-volume bone defects in clinic.