Histomorphometric and microtomographic analysis of maxillary sinus augmentation surgeries with and without collagen membrane on the lateral window: A randomized clinical trial.

OBJECTIVE: To evaluate the histomorphometric and computerized microtomographic (Micro-CT) analysis of the regenerated bone tissue from maxillary sinus augmentation surgery, with and without using the collagen membrane on the external osteotomy window. MATERIALS AND METHODS: Twelve patients were selected for this prospective, controlled, and randomized study. The patients were submitted to bilateral maxillary sinus surgery in a split-mouth design. On the test side, the maxillary sinus augmentation procedure included using Geistlich Bio-Oss® and a Geistlich Bio-Gide® collagen membrane covering the lateral osteotomy window. On the control side, only Geistlich Bio-Oss® was used without the presence of the membrane. After 6 months, the surgeries for implant installation were performed. In this surgical phase, specimens of the regenerated tissue were collected for histological and Micro-CT analysis. RESULTS: In the histomorphometric evaluation, the mean (±SD) percentages of newly formed bone were 43.9% (±11.5) and 40.8% (±8.9) in the test and control groups, respectively. The corresponding values of the Micro-CT analysis were 36.6% (±3.4) and 37.2% (±4.7) in the test and control groups, respectively. There was no statistically significant difference between the test and control groups in the two methods. In addition, there was no statistically significant difference between the mean percentage of biomaterial remaining between the test and control groups. However, the mean percentage of newly formed bone was significantly higher and the mean percentage of remaining biomaterial was significantly lower in the histomorphometric analysis compared to the values obtained through microtomography. CONCLUSION: The additional use of collagen membranes in maxillary sinus surgery does not offer advantages in newly formed bone.

Additive Manufacturing Titanium Dental Implants Placed in Sinuses Grafted with 70HA:30-TCP: A One-Year Retrospective Study for Evaluation of Survival Rate.

The present short-term retrospective study evaluated the implant survival rate and peri-implant bone loss around additive-manufactured titanium implants placed in sinuses grafted with Plenum Osshp (Plenum Bioengenharia, Jundia, SP, Brazil) (70HA:30ß-TCP) material. A total of 39 implants were inserted after 23 sinus floor elevation procedures in 16 consecutive patients. Prosthetic rehabilitation included fixed partial prostheses (three units), single crowns (eleven units), and fixed full arches (three units). Clinical and radiographic parameters of implant-supported restorations were evaluated after at least one year of occlusal loading. The implant-crown success criteria included the absence of pain, suppuration, and clinical mobility, an average distance between the implant shoulder and the first visible bone contact (DIB) < 1.0 mm from the initial surgery, and the absence of prosthetic complications at the implant-abutment interface. The overall cumulative implant survival rate was 97.43%. No prosthetic complications at the implant-abutment interface were reported. After one year, the mean DIB was 0.23 mm ± 0.14. Within the limits of this retrospective study, it can be concluded that 70 HA:30 ß-TCP allowed stable and reliable bone support to maintain healthy conditions around titanium dental implants produced by additive manufacturing.

In vitro and in vivo assessment of CaP materials for bone regenerative therapy. The role of multinucleated giant cells/osteoclasts in bone regeneration.

In this work, bone formation/remodeling/maturation was correlated with the presence of multinucleated giant cells (MGCs)/osteoclasts (tartrate-resistant acid phosphatase [TRAP]-positive cells) on the surface of beta-tricalcium phosphate (ß-TCP), sintered deproteinized bovine bone (sDBB), and carbonated deproteinized bovine bone (cDBB) using a maxillary sinus augmentation (MSA) in a New Zealand rabbit model. Microtomographic, histomorphometric, and immunolabeling for TRAP-cells analyses were made at 15, 30, and 60 days after surgery. In all treatments, a faster bone formation/remodeling/maturation and TRAP-positive cells activity occurred in the osteotomy region of the MSA than in the middle and submucosa regions. In the ß-TCP, the granules were rapidly reabsorbed by TRAP-positive cells and replaced by bone tissue. ß-TCP enabled quick bone regeneration/remodeling and full bone and marrow restoration until 60 days, but with a significant reduction in MSA volume. In cDBB and sDBB, the quantity of TRAP-positive cells was smaller than in ß-TCP, and these cells were associated with granule surface preparation for osteoblast-mediated bone formation. After 30 days, more than 80% of granule surfaces were surrounded and integrated by bone tissue without signs of degradation, preserving the MSA volume. Overall, the materials tested in a standardized preclinical model led to different bone formation/remodeling/maturation within the same repair process influenced by different microenvironments and MGCs/osteoclasts. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 108B:282-297, 2020.

Biphasic hydroxyapatite and ß-tricalcium phosphate biomaterial behavior in a case series of maxillary sinus augmentation in humans.

OBJECTIVES: The aim of this study was to evaluate and compare the morphometric components and the histological properties of pristine bone and bone grafted with a biphasic ß-tricalcium phosphate in humans using the maxillary sinus model. Reparative mesenchymal stem cells in the pristine bone and graft were also evaluated. MATERIALS AND METHODS: For this prospective case series, sinus augmentation was performed using a biphasic ß-tricalcium phosphate. After 6 months of healing, a core of remnant native alveolar bone and grafted bone was collected with a trephine. Histological, histomorphometrical, and immunohistochemical techniques were performed. Radiological analysis through cone beam computerized tomography was also conducted. RESULTS: A total of 10 patients were enrolled in this study. Radiologically, patients showed an average increase of crestal bone of 8.03 ± 1.72 mm. Morphologically, the grafted area was composed by 34.93 ± 14.68% of new mineralized tissue, 9.82 ± 11.42% of remnant biomaterial particles, and 55.23 ± 11.03% non-mineralized tissue. Histologically, we found no differences in the number of osteocytes per mm2 (p = 0.674), osteoblasts (p = 0.893), and blood vessels (p = 0.894) in the grafted area compared to the pristine bone. Differences were found on the number of osteoclasts (15.57 ± 27.50 vs. 5.37 ± 16.12, p = 0.027). The number of Musashi-1 positive mesenchymal cells (239.61 ± 177.4 vs. 42.11 ± 52.82, p = 0.027) was also significantly higher in the grafted area than in the pristine bone. CONCLUSION: Biphasic ß-tricalcium phosphate is a suitable biomaterial to be used in the formation of new bone in sinus floor elevation procedures in humans, not only from the histomorphometrical point of view, but also regarding the cellular and vascular quality of the regenerated bone.

Autogenous bone combined with anorganic bovine bone for maxillary sinus augmentation: analysis of the osteogenic potential of cells derived from the donor and the grafted sites.

OBJECTIVES: This study aimed to comparatively evaluate the in vitro osteogenic potential of cells obtained from the mandibular ramus (MR, autogenous bone donor site) and from the maxillary sinus (MS) bone grafted with a mixture of anorganic bovine bone (ABB) and MR prior to titanium implant placement (MS, grafted implant site). MATERIAL AND METHODS: Cells were obtained from three patients subjected to MS floor augmentation with a 1 : 1 mixture of ABB (GenOx Inorg(®) ) and MR. At the time of the sinus lift procedure and after 8 months, prior to implant placement, bone fragments were taken from MR and MS, respectively, and subjected to trypsin-collagenase digestion for primary cell culturing. Subcultured cells were grown under osteogenic condition for up to 21 days and assayed for proliferation/viability, osteoblast marker mRNA levels, alkaline phosphatase (ALP) activity and calcium content/Alizarin red staining. ALP activity was also determined in primary explant cultures exposed to GenOx Inorg(®) (1 : 1 with MR) for 7 days. Data were compared using either the Mann-Whitney U-test or the Kruskal-Wallis test. RESULTS: MS cultures exhibited a significantly lower osteogenic potential compared with MR cultures, with a progressive increase in cell proliferation together with a decrease in osteoblast markers, reduced ALP activity and calcium content. Exposure of MR-derived primary cultures to GenOx Inorg(®) inhibited ALP activity. CONCLUSION: These results suggest that the use of GenOx Inorg(®) in combination with MR fragments for MS floor augmentation inhibits the osteoblast cell differentiation at the implant site in the long term.

Levantamento de seio maxilar por acesso crestal e pressão hidrodinâmica com instalação imediata de implantes / Maxillary sinus lifting with crestal access and hydrodinamic pressure for immediate implant placement

A instalação de implantes dentários na região posterior de maxila pode ser dificultada pela diminuição da quantidade óssea e pelo aumento do seio maxilar. Este artigo relata um caso clínico de instalação de implantes nessa região, com extensa reabsorção óssea e pneumatização do seio maxilar. O paciente foi submetido a um procedimento de elevação da membrana do seio utilizando um sistema de pressão hidrodinâmico, seguido pelo preenchimento com osso xenógeno liofilizado e instalação imediata de implantes. Após um período de seis meses de cicatrização, verificou-se que esse sistema permitiu, de maneira segura e atraumática, a instalação de implantes dentários, preservando o espaço sinusal.

The placement of dental implants in the posterior maxilla may be impaired by the reduced bone quantity and increased maxillary sinus volume. This article reports a case of implant placement with large bone resorption and pneumatization of the maxillary sinus. The patient was submitted to a sinus lifting membrane procedure using a hydrodynamic pressure system followed by filling with lyophilized xenogeneic bone and immediate implant placement. After six months of healing, the clinical results demonstrated that this system provides safe and atraumatic dental implant placement while preserving sinus space.

Elevación de piso de seno maxilar: consideraciones anatómicas y clínicas: revisión de la literatura / Maxillary sinus augmentation: anatomic and clinic considerations: literature review

La elevación de piso de seno maxilar es uno de los procedimientos preimplantares másrealizados en la práctica odontológica. El objetivo de este artículo es reportar la evidenciadisponible sobre las implicaciones anatómicas y clínicas del procedimiento de elevación depiso para toma de decisiones clínicas. A partir de una búsqueda en la base Pubmed, se hizouna revisión de literatura de artículos publicados en revistas de odontología y otorrinolaringologíaentre 1980 y el 2011. La literatura encontrada se organizó en los siguientes temas:anatomía del seno maxilar, patología del seno maxilar, técnica de elevación de piso deseno maxilar y complicaciones por elevación de piso de seno maxilar. Con relación a otrosprocedimientos con la misma indicación, la elevación de seno maxilar es el más reportadoy ofrece los resultados más predecibles. Hay pocos estudios que reportan complicacionespor elevación de piso de seno maxilar y su manejo...

Maxillary sinus augmentation is one of most commonly performed clinical dental proceduresprevious to implant treatment. The aim of this article is to report the available literatureabout anatomical and clinical implications of the maxillary sinus lift procedure to supportclinical decisions. A literature review of articles published between 1980 and 2011 in dentaland otolaryngology journals was carried out at the Pubmed database. Found referenceswere grouped in the following themes: maxillary sinus anatomy, maxillary sinus pathology,maxillary sinus augmentation technique, and complications for maxillary sinus augmentation.Among other procedures performed for similar conditions, maxillary sinus augmentationis the most reported and the one that provides the most predictable results. Only afew studies report complications and management problems with the maxillary sinus lift...