E. Calciolari

Panoramic Measures for Oral Bone Mass in Detecting Osteoporosis A Systematic Review and Meta-Analysis

Different quantitative and qualitative indices calculated on oral panoramic radiographs have been proposed as useful tools to screen for reduced skeletal bone mineral density (BMD). Our aim was to systematically review the literature on linear and qualitative panoramic measures and to assess the accuracy of these indices by performing a meta-analysis of their sensitivity and specificity. The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement was followed. Fifty studies were included in the qualitative appraisal and 19 were considered for meta-analysis. The methodological quality of the retrieved studies, assessed with the QUADAS-2 tool, was on average low. Three indices were reported by most of the studies: mandibular cortical width, panoramic mandibular index, and the Klemetti index. Mandibular cortical width presented with a better accuracy in excluding osteopenia/osteoporosis (specificity), since patients with a cortical width more than 4 mm had a normal BMD in 90% of the cases. Almost all studies used a cutoff of 0.3 for the panoramic mandibular index, resulting in an estimated sensitivity and specificity in detecting reduced BMD, respectively, of 0.723 (SE 0.160; 95% confidence interval [CI], 0.352–0.926) and 0.733 (SE 0.066; 95% CI, 0.587–0.841). The presence of any kind of mandibular cortical erosion gave an estimated sensitivity and specificity in detecting reduced BMD, respectively, of 0.789 (SE 0.031; 95% CI, 0.721–0.843) and 0.562 (SE 0.047; 95% CI, 0.47–0.651) and a sensitivity and specificity in detecting osteoporosis, respectively, of 0.806 (SE 0.105; 95% CI, 0.528–0.9200) and 0.643 (SE 0.109; 95% CI, 0.417–0.820). The mandibular cortical width, panoramic mandibular index, and Klemetti index are overall useful tools that potentially could be used by dentists to screen for low BMD. Their limitations are mainly related to the experience/agreement between different operators and the different image quality and magnification of the panoramic radiographs.

Dental implants in patients affected by systemic diseases.

Several systemic diseases (and relative medications) have been reported to impair or in some cases complicate dental implant surgery. In broader terms, when dealing with patients suffering from systemic diseases, the monitoring of the medical condition and of the related post-operative complications is of great importance in order to avoid risks which could jeopardise the health of the patient. In this review, the available evidence on implant survival/success, as well as relevant surgical recommendations in patients affected by systemic diseases, are evaluated and when possible, practical suggestions for the clinician are provided.

A systematic review on the correlation between skeletal and jawbone mineral density in osteoporotic subjects

OBJECTIVES The aim of this systematic review was to assess whether the systemic skeletal reduction of bone mineral density (BMD) that characterizes osteoporotic subjects is also associated with a reduction of BMD in the jawbones. MATERIAL AND METHODS Two reviewers searched independently and in duplicate three databases up to May 2014 and assessed the risk of bias using a tailored version of the Newcastle-Ottawa scale (NOS). Only papers reporting either Pearsons correlation coefficient or Spearmans rank correlation coefficient between skeletal and jawbone mineral density in more than five osteoporotic subjects were selected. RESULTS From 1763 citations, 64 full-text papers were screened and five papers that met the inclusion criteria were included in the final analysis. None of the included studies complied with all NOS criteria, and as only two studies were eligible for meta-analysis, this was not performed. CONCLUSIONS Only limited conclusions can be drawn from this systematic review, due to the small number of studies included, their heterogeneity, and their high risk of bias. Future studies that take into consideration both upper and lower jaws, that use the same technique to measure skeletal and jaw BMD (ideally dual-energy X-ray absorptiometry, DXA), and that account for confounding variables (such as medications/diseases affecting bone metabolism and demographics) are needed to provide more robust conclusions.

Osteoporotic Animal Models of Bone Healing: Advantages and Pitfalls.

ABSTRACT The aim of this review was to summarize the advantages and pitfalls of the available osteoporotic animal models of bone healing. A thorough literature search was performed in MEDLINE via OVID and EMBASE to identify animal studies investigating the effect of experimental osteoporosis on bone healing and bone regeneration. The osteotomy model in the proximal tibia is the most popular osseous defect model to study the bone healing process in osteoporotic-like conditions, although other well-characterized models, such as the post-extraction model, might be taken into consideration by future studies. The regenerative potential of osteoporotic bone and its response to biomaterials/regenerative techniques has not been clarified yet, and the critical size defect model might be an appropriate tool to serve this purpose. Since an ideal animal model for simulating osteoporosis does not exist, the type of bone remodeling, the animal lifespan, the age of peak bone mass, and the economic and ethical implications should be considered in our selection process. Furthermore, the influence of animal species, sex, age, and strain on the outcome measurement should be taken into account. In order to make future studies meaningful, standardized international guidelines for osteoporotic animal models of bone healing need to be set up.

The use of omics profiling to improve outcomes of bone regeneration and osseointegration. How far are we from personalized medicine in dentistry

Increased life expectancy and broader restorative dental treatment alternatives for missing teeth have resulted in an increasing request of bone regeneration/augmentation procedures not only in healthy patients, but also in elderly and medically compromised ones. This is also combined with a growing demand for short implant loading protocols and for optimal aesthetic results. In order to meet these new dental needs, personalized treatment strategies tailored on each individuals characteristics and healing profile are warranted. Omics technologies are emerging as powerful tools to uncover molecules and signalling pathways involved in bone formation and osseointegration and to investigate differences in the molecular mechanisms between health and systemic diseases that could be targeted by future therapies. This review critically appraises the available knowledge on the application of omics technologies in the field of bone regeneration and osseointegration and explores their potential use for personalized medicine in the dento-maxillo-facial field. SIGNIFICANCE The use of omics in personalising dental maxillo-facial treatments emerges as a desirable diagnostic and treatment strategy. Omics represent, in fact, powerful tools not only to shade light on the cascade of events taking place during bone formation/osseointegration, but also to identify specific signalling pathways and molecules that can be targeted by future therapies with the aim to enhance clinical outcomes in patients with compromised healing conditions.

Role of prostaglandin E2 in the modulation of Wnt canonical signaling in cells on microstructured titanium surfaces

Background Rough surface topography enhances the activation of Wnt canonical signaling, a pathway required for osteoblast differentiation. The present study investigated the effects of the modulation of prostaglandin E2 (PGE2) signaling on osteoblastic differentiation on titanium surfaces for endosseous implants with different topographies. Methods C2C12 cells were plated on polished or acid-etched/sand-blasted (SLA) titanium discs and stimulated with 1 μM PGE2 or 100 nM cyclooxygenase inhibitor indomethacin. Activation of Wnt canonical signaling was measured with a reporter system. Gene expression was measured in the same cell system by real-time polymerase chain reaction (RT-PCR). Osteoblastic MC3T3 cells were then plated on polished or SLA titanium discs with or without indomethacin, and their proliferation and the expression of osteoblast-specific genes was assessed by RT-PCR. Cell morphology was furthermore studied on SEM, and cell adhesion was assessed by fluorescent labeling of focal adhesion. Results PGE2 decreased Wnt signaling stimulation in cells growing on polished or SLA surfaces, while indomethacin increased the expression of Wnt target genes in C2C12 and MC3T3 cells, by reporter assay. Moreover, indomethacin increased the expression of early differentiation marker alkaline phosphatase in MC3T3 cells on polished discs and of late marker osteocalcin in cells on SLA titanium. Conclusions Prostaglandin signaling affects the activation of Wnt canonical pathway in osteoblastic and mesenchymal cells on microstructured surfaces.

Osseointegration in osteoporotic-like condition: A systematic review of preclinical studies

Osteoporosis is one of the most common skeletal disorders affecting a significant percentage of people worldwide. Research data suggested that systemic diseases such as osteoporosis could act as risk factors for osseointegration, jeopardizing the healing process and thus the predictability of dental implant success on compromised patients. It is well accepted that preclinical studies in animal models reproducing the osteoporotic condition are one of the most important stages in the research of new biomaterials and therapeutic modalities. The aim of this systematic review was to investigate whether osteoporosis compromises dental implant osseointegration in experimental osteoporotic-like conditions. A 3-stage systematic literature research was conducted in MEDLINE via OVID and EMBASE up to and including March 2017. Experimental studies reporting on dental implant osseointegration on different osteoporotic animal models were assessed. The studies had to report on the percentage of bone-to-implant contact (%BIC) as the primary outcome. ARRIVE guidelines for reporting on animal research were applied to evaluate the methodological quality and risk of bias of the studies. Fifty-seven studies met the inclusion criteria and were assessed qualitatively. The most adopted animal model was the rat. A variability of %BIC values was observed, ranging from 30% to 99% and from 26% to 94% for the healthy and osteoporotic group, respectively. The great majority (47) of the included studies concluded that estrogen deficiency significantly affects BIC values, 9 studies stated that it was not possible to observe statistical differences in BIC between ovariectomized and healthy groups and 1 study did not provide a comparison between the healthy and osteoporotic group. Owing to the great heterogeneity in implant surface, study design, observation time-points, site of implant placement and reported outcomes, a meta-analysis could not be performed. An overall high risk of bias was observed, owing to the limited information on animal housing and husbandry, baseline characteristics and health status, ethical statement and allocation to the experimental groups provided. Although the available studies seem to suggest a lower osseointegration in osteoporotic-like conditions, no robust conclusions can be drawn due to the great heterogeneity and overall low quality of the available studies. Future studies with emphasis on minimizing the possible sources of bias and evaluating osseointegration of dental implants placed into jawbones instead of long bones are warranted.

Maxillary Sinus Floor Augmentation Using an Equine-Derived Graft Material: Preliminary Results in 17 Patients

Objective Sinus floor elevation with lateral approach is probably the most frequently performed reconstructive procedure to rehabilitate posterior maxilla when a bone deficiency is present. Different graft materials have been proposed and tested, often with high clinical performances and predictable results. Histological analysis is required when evaluating new materials. We investigated human biopsies retrieved after sinus floor elevation procedure by histomorphometric evaluation to test the performance of an equine-derived bone grafting material. Study Design Seventeen consecutive patients were enrolled and sinus lift surgeries were performed using an equine bone graft. Six months after surgery, at implant placement, bone samples were collected. Histomorphometry analysis was carried out on decalcified samples. Results All surgeries were uneventful and no additional grafting was required prior to implant insertion. Forty percent of new bone formation was detected, which represented the most abundant tissue retrieved, followed by the residual graft material (33%) and fibrous tissue (27%). A significant reduction in particles size demonstrates a remodeling activity of the graft material. Conclusion Within the limitations of this study, this equine-derived bone graft proved to be an effective material to induce new bone formation in the sinus floor elevation procedure.

Tardive Dyskinesia, Oral Parafunction, and Implant-Supported Rehabilitation

Oral movement disorders may lead to prosthesis and implant failure due to excessive loading. We report on an edentulous patient suffering from drug-induced tardive dyskinesia (TD) and oral parafunction (OP) rehabilitated with implant-supported screw-retained prostheses. The frequency and intensity of the movements were high, and no pharmacological intervention was possible. Moreover, the patient refused night-time splint therapy. A series of implant and prosthetic failures were experienced. Implant failures were all in the maxilla and stopped when a rigid titanium structure was placed to connect implants. Ad hoc designed studies are desirable to elucidate the mutual influence between oral movement disorders and implant-supported rehabilitation.