Francesco Ferrarotti

Bone production by human maxillary sinus mucosa cells

The Schneider membrane is the mucosa that covers the inner part of the maxillary sinus cavities. The free surface is a ciliated pseudostratified epithelium, while the deeper portion is a highly vascularized connective tissue. The stromal fraction, bordering the bony wall of the sinus, after tooth loss can exhibit increased osteoclastic activity resulting in resorption of the bone in the posterior maxilla. Goal of our study was to isolate and characterize mesenchymal progenitors in the Schneiders membrane connective net and to evaluate their self ability to differentiate toward osteoblastic lineage, in absence of osteoinductive factors and osteoconductive biomaterials of support. This should indicate that maxillary sinus membrane represents an useful an approachable source of MSCs for bone tissue engineering and cell therapy and owns the intrinsic capacity to restore maxillary bone after tooth loss without the needing of biomaterials. J. Cell. Physiol. 227: 3278–3281, 2012.

Osteogenic Potential of Human Oral‐Periosteal Cells (PCs) Isolated From Different Oral Origin: An In Vitro Study

The periosteum is a specialized connective tissue containing multipotent stem cells capable of bone formation. In this study, we aimed at demonstrating that human oral periosteal cells derived from three different oral sites (upper vestibule, lower vestibule, and hard palate) represent an innovative cell source for maxillo‐facial tissue engineering applications in terms of accessibility and self‐commitment towards osteogenic lineage. Periosteal cells (PCs) were isolated from patients with different ages (20–30 yy, 40–50 yy, 50–60 yy); we then analyzed the in vitro proliferation capacity and the bone self‐commitment of cell clones culturing them without any osteogenic supplement to support their differentiation. We found that oral PCs, independently of their origin and age of patients, are mesenchymal stem cells with stem cell characteristics (clonogenical and proliferative activity) and that, even in absence of any osteogenic induction, they undertake the osteoblast lineage after 45 days of culture. These results suggest that oral periosteal cells could replace mesenchymal cells from bone marrow in oral tissue‐engineering applications. J. Cell. Physiol. 231: 607–612, 2016.

Soft tissue and crestal bone changes around implants with platform-switched abutments placed nonsubmerged at subcrestal position: a 2-year clinical and radiographic evaluation.

PURPOSE To evaluate crestal bone changes around implants with platform-switched abutments placed 1 mm subcrestally in a prospective clinical investigation. MATERIALS AND METHODS Forty consecutive systemically healthy patients (mean age ± standard deviation [SD], 55.2 ± 8.7 years) with one or more missing teeth were consecutively treated with 1-mm subcrestally positioned, platform-switched, tapered, full treated implants restored with coded abutments. A total of 58 implants were placed. Final restorations were delivered 4 to 8 months after implant insertion. Digital standardized periapical radiographs using customized film holders were obtained at the time of implant insertion, and at 12 and 24 months after final prosthesis placement. Marginal peri-implant bone levels were measured at the mesial and distal surfaces of each implant using digital image software. RESULTS All implants osseointegrated and were clinically stable at the 2-year follow-up. The cumulative survival rate was 100%. From implant insertion to the 2-year follow-up, the mean bone loss was 0.32 ± 0.37 mm. No significant differences related to sex, implant site, and bone density were observed. The mean midbuccal and interproximal soft tissue margin positions were 1.13 ± 0.5 mm and 1.15 ± 0.6 mm coronal to the prosthetic finish line, respectively. CONCLUSION There is limited clinical information regarding the amount of marginal bone loss around two-piece platform-switched implants placed at subcrestal positions. Results of this study suggest that platform switching and subcrestal location of the implant-abutment interface may be effective in reducing bone loss and in preserving esthetics around dental implants.

Osseous resective surgery with and without fibre retention technique in the treatment of shallow intrabony defects: a split‐mouth randomized clinical trial

AIM The aim of this split-mouth clinical trial was to compare the effectiveness of Apically Positioned Flap with Fibre Retention Osseous Resective Surgery (FibReORS) or Osseous Resective Surgery (ORS) in the treatment of periodontal pockets associated with intrabony defects ≤ 3 mm at posterior natural teeth. MATERIALS AND METHODS Twenty-six posterior sextants requiring osseous resective surgery were selected in 13 chronic periodontitis patients: 13 sextants were randomly assigned to ORS and 13 to FibReORS. Clinical evaluation of probing depth (PD), gingival recession and clinical attachment level was performed at baseline, 6 and 12 months postoperatively. Periapical radiographs were taken prior and after surgical treatment, at 6- and 12-month follow-up. RESULTS Ostectomy amounted to 1.0 ± 0.3 mm in the ORS group and to 0.4 ± 0.2 mm in the FibReORS group. At 12-month examination PD changes did not significantly differ between the experimental groups. ORS group showed significantly (p < 0.001) greater clinical attachment loss (2.2 ± 1.0 mm versus 1.0 ± 0.6 mm), radiographic bone resorption (0.43 ± 0.08 mm versus 0.13 ± 0.09 mm) and post-operative patient discomfort compared to FibReORS. CONCLUSION FibReORS resulted in similar PD reduction, but less ostectomy, clinical attachment loss and patient morbidity compared to ORS.

Regenerative Treatment of Periodontal Intrabony Defects Using Autologous Dental Pulp Stem Cells: A 1-Year Follow-Up Case Series

The present case series aimed to explore the potential clinical benefits of the application of dental pulp stem cells (DPSCs) in the regenerative treatment of deep intrabony defects. A total of 11 isolated intrabony defects in 11 chronic periodontitis patients were accessed with a minimally invasive flap and filled with DPSCs loaded on a collagen sponge. A tooth requiring extraction for impaction or malpositioning was used as an autologous source for DPSCs. An average clinical attachment level gain of 4.7 ± 1.5 mm associated with a residual mean probing depth (PD) of 3.2 ± 0.9 mm and remarkable stability of the gingival margin was observed at 1 year. Complete pocket closure (PD < 3 mm) was achieved in 63.6% of the experimental sites. Clinical outcomes were supported by the radiographic analysis showing a bone fill of 3.6 ± 1.9 mm.

Increased early inflammatory response and osteoclastic activity in gingival tissues following conventional osseous resective surgery compared with the fibre retention technique: a pilot study

BACKGROUND AND OBJECTIVE The retention of suprabony connective fibres attached into the root cementum during fibre retention osseous resective surgery (FibReORS) results in a more conservative intrasurgical removal of bone, and limits further bone loss and patient morbidity during healing, compared with conventional osseous resective surgery (ORS). This may be a result of the protective effect of preserved connective tissue over the interproximal sites and the lower activation of the inflammatory mechanisms. Thus, the aim of this pilot study was to compare the expression of inflammatory and osteoclastic activity markers in gingival tissues following FibReORS and ORS in the early postsurgical phase. MATERIAL AND METHODS Twenty-six posterior sextants requiring osseous resective surgery were selected in 13 patients with chronic periodontitis: 13 sextants were randomly assigned to ORS and 13 to FibReORS in a split-mouth design. Gingival biospies were collected during the surgical sessions and at suture removal. Tissue samples were analysed to evaluate the expression of proinflammatory and immunity regulatory mediators (interleukin-1α, C-X-C motif chemokine ligand 5, interferon-γ and tumour necrosis factor-α), cluster of differentiation 14 (CD14; a monocyte/macrophage marker) and TRAP (an osteoclast marker) using immunohistochemical, immunofluorescence and cytofluorimetric analyses, respectively. RESULTS Postsurgery, a higher number of inflammatory cells and stronger expression of proinflammatory cytokines were observed in the epithelium and connective tissue of ORS gingival samples compared with FibReORS gingival samples (p < 0.001). This was accompanied by increased numbers of CD14-positive and TRAP-positive cells. CONCLUSION Retention of the supracrestal connective fibres appears to reduce the postsurgical intensity of the host-mediated inflammatory response.

Increase in Periodontal Interleukin-1β Gene Expression Following Osseous Resective Surgery Using Conventional Rotary Instruments Compared with Piezosurgery: A Split-Mouth Randomized Clinical Trial.

The purpose of this study was to evaluate the early inflammatory response following osseous resective surgery (ORS) with Piezosurgery compared to commonly used diamond burs. A sample was selected of 24 bilateral posterior sextants requiring ORS in 12 chronic periodontitis patients in a split-mouth design. In 12 sextants, bone recontouring was performed using a piezoelectric device. In the contralateral sextants, rotary instruments were used. Sextants treated with Piezosurgery obtained similar 12-month clinical results but lower postsurgical gene expression of interleukin-1β (IL-1β), a well-known proinflammatory cytokine, and lower patient morbidity compared with sextants treated with rotary instruments. In spite of the longer surgical time, the use of Piezosurgery for ORS seems to promote more favorable wound healing compared with rotary instruments, as the lower pain and the low levels of IL-1β mRNA at the surgical sites suggest a milder underlying inflammatory response.

Enamel Matrix Derivative Proteins in Combination with a Flapless Approach for Periodontal Regeneration of Intrabony Defects: A 2-Year Prospective Case Series.

The present case series evaluated the potential benefits of a flapless approach in the regenerative treatment of residual deep intrabony defects. In each of 11 patients, one periodontal defect with an intrabony component of ≥ 3 mm was treated regeneratively using enamel matrix derivative combined with a closed surgical technique. Clinical and radiographic parameters were recorded at baseline and at 12 and 24 months postoperatively. All defects experienced favorable clinical and radiographic outcomes at the 24-month follow-up. When considering only sites located in the anterior region, all experienced complete pocket closure.

Effectiveness of Enamel Matrix Derivative in Conjunction with Particulate Autologous Bone in the Treatment of Noncontained Intrabony Defects: A 2-Year Prospective Case Series

This case series evaluated the healing of deep intrabony defects treated with a combination of enamel matrix derivative and autologous particulate bone harvested from the buccal and lingual/palatal cortical plate with a Piezosurgery device. A total of 15 defects with a predominantly one- or two-wall component were consecutively treated in 15 patients with advanced chronic periodontitis. In all selected sites, the three-wall component was ≤ 25% of the total defect depth. Clinical and radiographic parameters were recorded at baseline and 12 and 24 months postoperatively. All defects showed favorable clinical and radiographic outcomes at the 24-month follow-up. The probing depth reduction was 4.4 ± 1.6 mm, and more than 50% of the defects presented clinical attachment level gain of at least 5 mm. The bone fill was 3.1 ± 1.6 mm.

Occlusive Titanium Barrier for Immediate Bone Augmentation of Severely Resorbed Alveolar Sockets with Secondary Soft Tissue Healing: A 2-Year Case Series

This case series evaluated bone dimensional changes following the application of an occlusive titanium barrier on severely resorbed fresh extraction sockets to achieve bone regeneration. Six extraction sites with buccal bone loss were filled with a xenograft and covered with a titanium plate fixed by two miniscrews and left intentionally exposed. No infection occurred. After 4 months of healing, sufficient hard tissue had formed to allow implant insertion. Mean vertical bone gain was 7.3 ± 2.2 mm at the buccal side and 4.2 ± 1.2 mm at the lingual side. The average bone width augmentation was 23 ± 1.0 mm. At 24 months, all implants were clinically successful. Based on these preliminary findings, occlusive titanium barriers without primary closure may be successfully used in immediate alveolar reconstruction procedures.