Changes in Peri-implant Marginal Bone Level by Jaw Location: A Systematic Review and Meta-Analysis of 4970 Implants.

The purpose of this study was to evaluate the current evidence on marginal bone-level changes (ΔMBL) around internal connection implants with fixed prostheses by jaw location over time. An electronic literature search for ΔMBL (change in marginal bone level) was conducted in 6 databases. The data from the included manuscripts were categorized by jaw sextant of the implants and duration of follow-up (<2 years, 2-5 years, and >5 years). Meta-analyses were performed on groups with at least 5 studies. A total of 1270 records were screened. Full-text review of 413 papers resulted in a total of 46 studies (representing 2259 patients with 4970 implants) included for quantitative synthesis and analysis. The ΔMBL was summarized at 2 time intervals with the following results: <2 years (anterior maxilla = 0.393 mm [95% confidence interval {CI}, 0.172, 0.613], posterior maxilla = 0.468 mm [95% CI, 0.288, 0.648], and posterior mandible 0.559 mm [95% CI, 0.397, 0.72]), 2 to 5 years (anterior maxilla = 0.683 mm [95% CI, 0.224, 1.142], posterior maxilla = 0.645 mm [95% CI, 0.42, 0.87], and posterior mandible 0.563 mm [95% CI, 0.278, 0.849]). There were insufficient studies in the anterior mandible and with follow-up data over 5 years for quantitative synthesis. Within the limitations of this study, location within the maxillary and mandibular jaws does not seem to influence ΔMBL around internal connection bone level implants with fixed restorations. Although there may be a tendency for greater initial remodeling in the posterior mandible followed by long-term stability, additional studies are needed to evaluate this further.

Prader-Willi syndrome: Periodontal-prosthodontic rehabilitation in an adult patient.

INTRODUCTION: Prader-Willi syndrome (PWS) is a rare genetic multisystemic disease that is the most common inherited cause of severe childhood obesity. PWS patients are prone to significant oral and systemic health issues that detrimentally affect quality of life and decrease longevity. This report documents full-mouth pre-prosthetic surgical and restorative care in an adult PWS patient. CASE REPORT: The patient, a 29-year-old male, presented to the clinic accompanied by his guardians (parents) with the chief complaint that "My Teeth are breaking down and I would like to get them fixed". Periodontal and prosthetic comprehensive clinical and radiographic exams revealed a severely worn dentition, deep anterior overbite, altered passive eruption with generalized biofilm-induced gingivitis, and altered occlusal vertical dimension. Full mouth crown lengthening surgery combined with full mouth prosthodontic reconstruction was performed under parenteral sedation and local anesthesia. Completion of treatment was successful, and the patient was placed on a 3-month periodontal maintenance interval. DISCUSSION: Full mouth periodontal surgical and prosthodontic reconstruction on a PWS patient has not previously been reported in the literature. This case underscores the potential need for complex dental care in patients with this syndrome.

Alveolar ridge augmentation for implant placement in a growing patient.

BACKGROUND: Partial edentulism in growing children due to aplasia or trauma poses a difficult situation to manage. We present a case of horizontal ridge augmentation in a growing patient who had trauma in childhood when it was too early to place implants. METHODS AND RESULTS: This patient had a history of trauma, at age 13, that resulted in mandibular fracture and loss of teeth #23-27. The definitive restorative treatment plan was postponed due to the patient's continued growth. At age 18, horizontal bone augmentation was performed in a severely resorbed anterior mandible. After 7 months of healing, 7-8 mm ridge augmentation was achieved, and three implants were placed. Soft tissue augmentation by free gingival graft was performed at implant second stage surgery 4 months later. CONCLUSIONS: When considering the timing of implant placement in adolescents, the clinician walks a fine line between waiting as long as possible to place the implants and racing against continued resorption of the edentulous alveolar ridge. 70/30 mineralized/demineralized cortical bone allograft and injectable platelet-rich fibrin mix combined with tenting screws and resorbable membranes are useful measures for horizontal ridge augmentation in growing patients. KEY POINTS: Why is this case new information? There are insufficient data available when considering implant treatment in younger patients. The present case was managed with a variation of the sausage technique described by Urban. The use of allograft, I-PRF, and tenting screws replaced the use of autogenous bone and resulted in exceptional results. What are the keys to the successful management of this case? Delaying treatment until after the critical growth period has passed. Adequate flap release, tension-free primary flap closure, and space maintenance through the use of tenting screws and tacking the membranes using tacking pins provided support for the grafted site. What are the primary limitations to success in this case? The continued growth may cause infra occlusion of the implant-supported bridge.

A Tale of Two Fimbriae: How Invasion of Dendritic Cells by Porphyromonas gingivalis Disrupts DC Maturation and Depolarizes the T-Cell-Mediated Immune Response.

Porphyromonas gingivalis (P. gingivalis) is a unique pathogen implicated in severe forms of periodontitis (PD), a disease that affects around 50% of the US population. P. gingivalis is equipped with a plethora of virulence factors that it uses to exploit its environment and survive. These include distinct fimbrial adhesins that enable it to bind to other microbes, colonize inflamed tissues, acquire nutrients, and invade cells of the stroma and immune system. Most notable for this review is its ability to invade dendritic cells (DCs), which bridge the innate and adaptive immune systems. This invasion process is tightly linked to the bridging functions of resultant DCs, in that it can disable (or stimulate) the maturation function of DCs and cytokines that are secreted. Maturation molecules (e.g., MHCII, CD80/CD86, CD40) and inflammatory cytokines (e.g., IL-1b, TNFa, IL-6) are essential signals for antigen presentation and for proliferation of effector T-cells such as Th17 cells. In this regard, the ability of P. gingivalis to coordinately regulate its expression of major (fimA) and minor (mfa-1) fimbriae under different environmental influences becomes highly relevant. This review will, therefore, focus on the immunoregulatory role of P. gingivalis fimbriae in the invasion of DCs, intracellular signaling, and functional outcomes such as alveolar bone loss and immune senescence.

Selective Antimicrobial Therapies for Periodontitis: Win the "Battle and the War".

Traditional antimicrobial therapies for periodontitis (PD) have long focused on non-selective and direct approaches. Professional cleaning of the subgingival biofilm by instrumentation of dental root surfaces, known as scaling and root planning (SRP), is the mainstay of periodontal therapy and is indisputably effective. Non-physical approaches used as adjuncts to SRP, such as chemical and biological agents, will be the focus of this review. In this regard, traditional agents such as oral antiseptics and antibiotics, delivered either locally or systemically, were briefly reviewed as a backdrop. While generally effective in winning the "battle" against PD in the short term, by reducing its signs and symptoms, patients receiving such therapies are more susceptible to recurrence of PD. Moreover, the long-term consequences of such therapies are still in question. In particular, concern about chronic use of systemic antibiotics and their influence on the oral and gut microbiota is warranted, considering antibiotic resistance plasmids, and potential transfer between oral and non-oral microbes. In the interest of winning the "battle and the war", new more selective and targeted antimicrobials and biologics for PD are being studied. These are principally indirect, blocking pathways involved in bacterial colonization, nutrient acquisition, inflammation or cellular invasion without directly killing the pathogens. This review will focus on current and prospective antimicrobial therapies for PD, emphasizing therapies that act indirectly on the microbiota, with clearly defined cellular and molecular targets.

Epidemiology and reporting characteristics of preclinical systematic reviews.

In an effort to better utilize published evidence obtained from animal experiments, systematic reviews of preclinical studies are increasingly more common-along with the methods and tools to appraise them (e.g., SYstematic Review Center for Laboratory animal Experimentation [SYRCLE's] risk of bias tool). We performed a cross-sectional study of a sample of recent preclinical systematic reviews (2015-2018) and examined a range of epidemiological characteristics and used a 46-item checklist to assess reporting details. We identified 442 reviews published across 43 countries in 23 different disease domains that used 26 animal species. Reporting of key details to ensure transparency and reproducibility was inconsistent across reviews and within article sections. Items were most completely reported in the title, introduction, and results sections of the reviews, while least reported in the methods and discussion sections. Less than half of reviews reported that a risk of bias assessment for internal and external validity was undertaken, and none reported methods for evaluating construct validity. Our results demonstrate that a considerable number of preclinical systematic reviews investigating diverse topics have been conducted; however, their quality of reporting is inconsistent. Our study provides the justification and evidence to inform the development of guidelines for conducting and reporting preclinical systematic reviews.

A focused compound screen highlights the significance of epidermal growth factor receptor signalling in chordoma pathogenesis.

Chordoma is a rare primary bone cancer with limited treatment options. Surgical resection followed by radiotherapy has proven effective; however, when, in 30-40% of patients, tumours recur and metastasize, a high level of resistance to chemotherapies leaves these patients with a dearth of treatment options. Recent work published in the Journal of Pathology by Scheipl et al describing a focused compound drug screen highlights the significance of epidermal growth factor receptor (EGFR) signalling in chordoma, and shows potential for EGFR inhibitors as a way forward for developing an effective treatment for chordoma. Importantly, combining EGFR inhibitors with a MET inhibitor induces a synergistic effect on growth inhibition of resistant chordoma cells, highlighting the significance of combined EGFR and MET inhibitors as a potential avenue to defeat chemoresistance in chordoma patients. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.