Alessandra Lolato

Three-Dimensional Volume Change of Grafted Bone in the Maxillary Sinus

PURPOSE The purpose of this study was to evaluate the three-dimensional radiographic changes of 100% anorganic bovine bone xenograft volume in a grafted maxillary sinus, based on a computerized analysis of cone-beam computed tomography (CBCT) scan. MATERIALS AND METHODS A maxillary sinus augmentation procedure done with a lateral approach using 100% anorganic bovine bone was performed in 20 patients. A CBCT scan of the grafted area was taken immediately after the procedure (T1) and 8 to 9 months later (T2). CBCT scan data were analyzed with image processing software to evaluate differences in the volume of grafted material between T1 and T2. Residual ridge height and width were also measured at T1. RESULTS The mean residual bone height and width at the implant sites was 4.40±0.87 mm and 7.9±2.22 mm, respectively. The mean graft volume was 1,432±539 mm³ and 1,287±498 mm³ at T1 and T2, respectively. A significant difference in graft volume was found between T1 and T2 data by paired t test (P=.01). The mean ratio between the volume at T2 and the volume at T1 was 0.90±0.12, meaning a graft volume contraction of 10%. CONCLUSION Within the limits of the present investigation, good stability of anorganic bovine bone graft volume up to 8 months after the grafting procedure was demonstrated. Three-dimensional computed tomographic volumetric assessment seems to be a promising approach to quantify long-term changes in the regenerated area.

Autologous Platelet Concentrates for Pulp and Dentin Regeneration: A Literature Review of Animal Studies.

INTRODUCTION The purpose of this study was to evaluate the effectiveness of autologous platelet concentrates (APCs) in promoting pulp and dentin regeneration in animal models. METHODS An electronic search was performed on MEDLINE, Embase, Scopus, SciELO, LILACS, and CENTRAL. Animal studies using APC as a root filling material after pulpectomy in mature or immature teeth were included. Articles underwent risk of bias assessment. Histologic evaluation of intracanal neoformed tissue was the primary outcome; root development, root wall thickening, apical closure, and periapical healing in apical periodontitis were the secondary outcomes. RESULTS Seven articles were included. Platelet-rich plasma (PRP) was used as root filling material during regenerative procedures in the experimental group in either mature or immature teeth. After revascularization with PRP alone or in conjunction with stem cells of a different source, the histologic analyses revealed that, in addition to an odontoblastic cell layer or dentinlike structure, the neoformed intracanal tissues were mainly cementumlike, bonelike, and connective tissues. CONCLUSIONS True regeneration of necrotic pulp may not be achieved with current techniques using PRP, all of which stimulated tissue repair. Benefits of PRP adjunct for pulp tissue regeneration in preclinical studies remain unclear. Further studies with standardized protocols are necessary to assess the actual contribution of PRP in endodontic regenerative therapies.

Platelet concentrates for revitalization of immature necrotic teeth: a systematic review of the clinical studies

Abstract This systematic review aimed at determining the effectiveness of autologous platelet concentrate (APC) in the treatment of immature necrotic teeth. An electronic search was performed on MEDLINE, Embase, Scopus, SciELO, Lilacs, CENTRAL. Comparative clinical studies were included, in which APC was tested for pulp regeneration and radicular development. Selected articles underwent risk-of-bias assessment. Clinical and radiographic outcomes were considered. Three randomized parallel studies and one split-mouth case series were included. One study had low risk of bias and three studies had high risk. A total of 61 immature necrotic teeth were treated in 56 patients. Follow-up ranged between 12 and 18 months. All studies used platelet-rich plasma (PRP) in the test group, and one also used platelet-rich fibrin (PRF). After treatment, all teeth of control and experimental groups remained asymptomatic for the entire study duration. Only one study reported response to cold and electric pulp test, showing not significantly better outcomes for the test group. Similarly, periapical healing and apical closure were improved in the group treated with APC although statistical significance was not achieved (P = 0.08 and P = 0.06, respectively), probably due to the limited sample size. The teeth treated with PRP achieved significantly better thickening of the dentin walls (P = 0.01), and root lengthening (P = 0.001) than control teeth. Despite the potential effectiveness of APC in promoting root development of necrotic immature teeth, scarce evidence exists regarding this subject. In the studies evaluated in this review, platelet concentrates showed promising results that warrant further investigation.

Pathophysiology of sinusitis of odontogenic origin

Sinusitis of odontogenic origin, which is frequently encountered in routine otolaryngological and dental clinical practice, has been described as a reactive maxillary inflammation secondary to maxillary tooth infection or trauma to an odontogenic disease of maxillary bone, dental extractions, implant placement, or endodontic treatment impairing the integrity of the Schneiderian membrane. The aim of the present review was to investigate and discuss the most recent pathophysiological findings, predisposing odontogenic factors, microbiology, and the possible involvement of bacterial biofilms (BB) in the development of sinusitis. The narrative literature review showed that there might be a correlation between the bacteria present in pathological teeth in communication with the sinus and those found in infected sinus. The formation of a BB might be also involved in the etiopathogenesis of sinusitis of odontogenic origin. In conclusion, the true origin of odontogenic sinusitis is still unresolved. In clinical terms, the choice of suitable therapy depends on the characteristics of the biofilm. Further microbiological studies are required to better investigate the role of BB.

Methodological Quality Assessment of Systematic Reviews on Autologous Platelet Concentrates for the Treatment of Periodontal Defects

Objectives Evaluation of the methodological quality of systematic reviews (SRs) on the effectiveness of autologous platelet concentrates as an adjunct to regenerative procedures for the treatment of periodontal defects. Material and Methods After a literature screening, eligible SRs were qualitatively assessed using 2 validated instruments: A Measurement Tool to Assess systematic Reviews checklist and Overview Quality Assessment Questionnaire. The characteristics and findings of SRs were also reported. Results Ten SRs fulfilled the inclusion criteria and were evaluated. With A MeaSurement Tool to Assess systematic Reviews tool, SRs displayed a generally satisfying quality. Six SRs satisfied ≥8 items of 11 (high‐quality score), and 4 were classified of medium quality (score 4–7). Using Overview Quality Assessment Questionnaire instrument, more than half SRs (N = 6) satisfied ≥7 items of 9, resulting to be of high quality; 3 were classified as medium quality (4–6 criteria met); and only 1 of low quality (3 items satisfied). A significant correlation between the results of the 2 questionnaires was found (Spearmans r = 0.915, P = .0005). Conclusions SRs considered had an overall high methodological quality. However, some areas were not systematically addressed, like a thorough research strategy or publication bias assessment. Standard guidelines for designing, performing, and reporting SRs should always be followed. The use of platelet concentrates as an adjunct to periodontal surgery procedures may have beneficial effects for the treatment of periodontal defects.

Effect of an Activated Platelet Concentrate on Differentiated Cells Involved in Tissue Healing.

Abstract Tissue healing is a complex process involving several players such as cells and growth factors released from platelets upon activation. Today, platelet concentrates (PCs) are used in many different medical fields including oral, orthopaedic, and reconstructive surgery since they allow growth factors delivery to the injured site, aiming at enhancing tissue regeneration. The purpose of this in vitro study was to evaluate the effect of the acellular plasma of an activated platelet concentrate obtained using a manual protocol, on the proliferation, and biological activity of differentiated cells involved in tissue healing. Human osteoblasts and dermal fibroblasts were grown in serum-free medium supplemented with PC derived from several donors. Human osteoblast and human dermal fibroblast proliferation was assessed by MTT test after 7 days and cells were count up to 12-day incubation. Human osteoblast osteo-differentiation was tested after 7 and 14-day incubation by alkaline phosphatase assay. The addition of PC to the culture medium caused an increased proliferation with respect to cells grown in standard condition. The results of the present study suggest that PC supports the proliferation of terminally differentiated cells involved in wound healing and tissue regeneration, confirming its beneficial clinical application in regenerative therapies.

Does Freeze–Thawing Influence the Effects of Platelet Concentrates? An In Vitro Study on Human Adipose-Derived Stem Cells

AbstractHuman adipose-derived stem cells (hASCs) have been proposed as a possible therapy for tissue regeneration in aesthetic, plastic, and reconstructive surgery. Today, platelet concentrates are used in a wide range of disciplines, but their storage has become a controversial aspect. The purpose of this in vitro study was to evaluate the effect of plasma rich in growth factors (PRGF), after a freeze–thawing cycle, on the proliferation and biological activity of progenitor cells involved in soft tissue healing. Different formulations of activated PRGF were added to hASCs cultured in serum-free medium. Cell proliferation was assessed by MTT test and cell count up to 7 and 12-day incubation. Osteo-differentiation ability of hASCs was also tested after 7 and 14-day incubation by alkaline phosphatase assay. The effects of 4 PRGF preparations (fresh/frozen and with/without platelets) were compared with corresponding formulations of plasma poor in growth factors and with standard medium. hASCs cultured in the presence of platelet concentrates increased proliferation rate with respect to cells grown in standard medium without significant differences among all the tested plasma formulations on cell viability up to 12 days of culture. PRGF activity is preserved after cryopreservation and platelet-rich preparations promoted osteo-differentiation of hASCs at day 7. In conclusion, PRGF supports the proliferation and the differentiation of progenitor cells in vitro also when applied after cryopreservation. Platelet concentrates, either alone or in combination with mesenchymal stem cells, might be a valuable tool in the field of tissue regeneration.