Felice Lorusso

Soft Tissue Augmentation of the Face With Autologous Platelet-Derived Growth Factors and Tricalcium Phosphate. Microtomography Evaluation of Mice.

Background:The platelets used in oral, maxillofacial, and plastic surgery are generally grouped as concentrated platelet-rich plasma. The general principle of production consists of a centrifugation, making it possible to eliminate red blood cells, then acellular plasma, to preserve only the concentrated platelets. Objective:The aim of the present study was that micro porous tricalcium phosphate (&bgr;-TCP) mixed with autologous platelet-derived growth factors could be an alternative to fat and hyaluronic acid which are widely used for oral and maxillofacial soft tissue augmentation. Methods:Ten female, 6 to 8-week-old black-haired mice were selected. On 1 cheek was injected the gel of tricalcium phosphate/autologous platelet-derived growth factors, while on the other cheek, was left empty and was used as control. The animals were killed after 8 weeks. Investigator evaluation was based on microtomography observation and comparison of control and test. Results:The microtomography technique demonstrated amorphous radiopaque images projected in the soft tissue parts of each paramedian region of the right cheek, in those sites corresponding to the injection of the gel of tricalcium phosphate/autologous platelet-derived growth factor. Eight weeks after surgery, &bgr;-TCP granules were clearly visible with most remaining within the cheek. The margins of the &bgr;-TCP granules were clear and not diffused within the vicinity of the tissues. Conclusion:The results indicate that micro &bgr;-tricalcium phosphate Ca3(PO4)2 mixed with autologous platelet-derived growth factors material was able to create a lasting three-dimensional soft tissue augmentation and is a promising biomaterial for soft tissue augmentation as a scaffold for cells.

Bone Regeneration Induced by Bone Porcine Block with Bone Marrow Stromal Stem Cells in a Minipig Model of Mandibular “Critical Size” Defect

Introduction. Adding stem cells to biodegradable scaffolds to enhance bone regeneration is a valuable option. Different kinds of stem cells with osteoblastic activity were tested, such as bone marrow stromal stem cells (BMSSCs). Aim. To assess a correct protocol for osteogenic stem cell differentiation, so BMSSCs were seeded on a bone porcine block (BPB). Materials and Methods. Bone marrow from six minipigs was extracted from tibiae and humeri and treated to isolate BMSSCs. After seeding on BPB, critical-size defects were created on each mandible of the minipigs and implanted with BPB and BPB/BMSSCs. After three months, histomorphometric analysis was performed. Results. Histomorphometric analysis provided percentages of the three groups. Tissues present in control defects were 23 ± 2% lamellar bone, 28 ± 1% woven bone, and 56 ± 4% marrow spaces; in BPB defects were 20 ± 5% BPB, 32 ± 2% lamellar bone, 24 ± 1% woven bone, and 28 ± 2% marrow spaces; in BPB/BMSSCs defects were 17 ± 4% BPB/BMSSCs, 42 ± 2% lamellar bone, 12 ± 1% woven bone, and 22 ± 3% marrow spaces. Conclusion. BPB used as a scaffold to induce bone regeneration may benefit from the addition of BDPSCs in the tissue-engineered constructs.

Sinus Augmentation with Biomimetic Nanostructured Matrix: Tomographic, Radiological, Histological and Histomorphometrical Results after 6 Months in Humans

Background: Many bone substitutes have been applied for sinus regeneration procedures, such as autogenous bone, inorganic bovine bone, porous and resorbable hydroxyapatite, tricalcium phosphate, bioactive glass, and blood clots. The aim of the present study was a tomographic, histological and histomorphometrical evaluation in humans, of specimens retrieved from sinuses augmented with MgHA/collagen-based scaffolds, after a healing period of 6 months. Materials and Methods: Eleven healthy patients and a total of 15 sinuses were included in this study. The maxillary sinuses were filled with commercial MgHA/collagen-based scaffolds (RegenOss) with a porous three-dimensional (3D) structure (Fin-Ceramica Faenza S.p.A., Faenza, Italy). These grafts have a composite design, that replicate the organization of bone structure, obtained by a technique in which a specific hybrid organic–inorganic composite is spontaneously built by a biological mechanism. The CBCT scans were done before the procedure, after the surgical protocol (T1), and 6 months after sinus surgery (T2) for implantology. Bone specimens were stored in 10% formalin solution, embedded in a glycolmethacrylate resin and sectioned by a high-precision diamond disc. Histologic and histomorphometric analysis were carried out to evaluate the graft reabsorption and bone healing. Results: The mean volume after graft elevation, calculated for each of the 15 sinuses, was 2,906 mm3 in the immediate postoperative period (5–7 days), ranging from 2,148.8 to 3,146.4 mm3. In the late postoperative period (6 months) it was 2,806.7 mm3, ranging from 2,010.9 to 3,008.9 mm3. The sinuses were completely healed and no residual MgHA/collagen-based scaffolds were visible. Osteoblasts appeared actively secreting bone matrix and marrow spaces contained moderate numbers of stromal cells and vascular network. Osteoblasts were observed actively secreting osteoid matrix. The tissues present in the samples were composed of 1.9 ± 1.9% of lamellar bone, 36 ± 1% of woven bone and 58 ± 3.8% of marrow spaces. Conclusion: Mg-MgHA/collagen-based scaffolds can successfully be used for sinus augmentation procedures.

Bone Regeneration in Iliac Crestal Defects: An Experimental Study on Sheep.

Background. Oral rehabilitation of partially fully edentulous patients with dental implants has become a routine procedure in clinical practice. In a site with a lack of bone GBR is a surgical procedure that provides an augmentation in terms of volume for the insertion of dental implants. Materials and Methods. In the iliac crest of six sheep 4 defects were created where an implant was inserted, three of them with different biomaterials and a control site. All animals were sacrificed after a 4-month healing period. All specimens were processed and analyzed with histomorphometry. Statistical evaluation was done to evaluate percentage of bone defect filled by new bone. Results. All experimental groups showed an increase of the new bone. Higher and highly statistically significant differences were found in the percentages of bone defect filled by new bone in group filled with corticocancellous 250–1000 microns particulate porcine bone mix. Conclusions. This study demonstrates that particulate porcine bone mix and porcine corticocancellous collagenate prehydrated bone mix when used as scaffold are able to induce bone regeneration. Moreover, these data suggest that these biomaterials have higher biocompatibility and are capable of inducing faster and greater bone formation.

Three-Dimensional Architecture and Mechanical Properties of Bovine Bone Mixed with Autologous Platelet Liquid, Blood, or Physiological Water: An In Vitro Study

In recent years, several techniques and material options have been investigated and developed for bone defect repair and regeneration. The progress in studies of composite graft materials and autologous platelet-derived growth factors for bone regeneration in dentistry and their biological and biomechanical properties has improved clinical strategies and results. The aim of this study was to evaluate the three-dimensional architecture and mechanical properties of three different combinations of composite bovine graft, adding autologous platelet liquid (APL), blood, or physiological water. One experimental group for each combination of biomaterials was created. In particular, in Group I, the bovine graft was mixed with APL; in Group II, it was mixed with blood, and in Group III, the biomaterial graft was combined with physiological water. Then, the composite biomaterials were evaluated by scanning electron microscopy (SEM), and a compression-loading test was conducted. The evaluation showed a statistical significance (p < 0.01) of the elastic regime of deformation resistance, in which the combination of APL with bone graft resulted in an 875% increase in the mechanical resistance. The protocol of APL mixed with bovine bone graft produced a composite sticky graft block that was capable of increasing the mechanical properties in order to improve its clinical use in the treatment of the maxillary bone defects.

Lateral Sinus Floor Elevation Performed with Trapezoidal and Modified Triangular Flap Designs: A Randomized Pilot Study of Post-Operative Pain Using Thermal Infrared Imaging

Purpose: Post-operative pain and swelling are frequently observed after sinus lift procedures. The aim of the present study was the clinical evaluation of swelling and pain of two different sinus flap lift techniques using a visual analogue scale (VAS), verbal rating scale (VRS), and infrared thermal imaging (i.e., thermography). Materials Methods: A randomized controlled trial was conducted with 15 patients (30 sinuses in total) randomly allocated into two groups. For the sinuses of Group I a trapezoidal flap was used, while for Group II a modified triangular flap without anterior release was utilized. Postoperative pain was scored by means of a 100-mm VAS ranging from 0 (no pain) to 100 (worst pain imaginable), and was recorded at 2, 4, 6 and 14 days after surgery. Swelling was recorded by a verbal rating scale (VRS) and was classified into four categories: a score of 1 referred the absence of swelling, patients with intra-oral swelling in the surgical zone scored 2, any extra-oral swelling in the surgical zone scored 3, and intense swelling exhibited by extra-oral swelling extending beyond the surgical zone scored 4. The facial temperature was recorded before and after sinus augmentation, and at 2, 4, 6, and 14 days post-surgery to check the course of healing. Results: In Group I pain intensity was recorded at 2 days after surgery with a mean score of 38.67 ± 6.4 mm. Swelling was greater at 2 and 4 days, and was absent at day 6. The facial temperature difference before and after the procedure was 4.737 °C ± 0.37. In Group II the pain score were lower than in Group I (p < 0.05). The score for swelling was 2 on the first and second days, and was reduced on day 4. After the second day the difference in temperature was significantly reduced as compared to the day of surgery (0.77 °C); at 2 and 4 days no difference was registered. Conclusions: The results of this clinical study show the significant effectiveness of the modified triangular flap in the sinus lift procedure for reducing pain and swelling.

Neurosensory Disturbance of the Inferior Alveolar Nerve After 3025 Implant Placements

Purpose: The aim of this retrospective study was to evaluate the incidence of inferior alveolar nerve (IAN) lesion and duration of sensitivity disturbances after the insertion of dental implants. Methods: One thousand sixty-five patients (mean age: 58.9 years) enrolled between February 2004 and July 2015 with partial or full mandibular edentulism were selected to receive dental implants for oral rehabilitation. A total of 3025 implants were placed. After surgical procedures, controls were scheduled at suture removal, that is, 10 days after surgery, and repeated at intervals of 1, 3, and 6 months, and comprised patient interview, clinical examination, and sensitivity tests. Results: Only 23 (2.2%) of the 1065 patients presented sensitivity disturbances 1 month after implant insertion, and only 2 (0.19%) after 6 months, though a complete recovery was observed in these patients within 13 months. Conclusions: Considering the debilitating effects resulting from IAN lesion and the complexity of the therapeutic diagnostic protocols, all patients undergoing oral rehabilitation through dental implants should be evaluated with CBCT imaging.

Bone Response to Two Dental Implants with Different Sandblasted/Acid-Etched Implant Surfaces: A Histological and Histomorphometrical Study in Rabbits

Background Scientific evidence in the field of implant dentistry of the past 20 years established that titanium rough surfaces have shown improved osseointegration rates. In a majority of dental implants, the surface microroughness was obtained by grit blasting and/or acid etching. The aim of the study was to evaluate in vivo two different highly hydrophilic surfaces at different experimental times. Methods Calcium-modified (CA) and SLActive surfaces were evaluated and a total of 18 implants for each type of surface were positioned into the rabbit articular femoral knee-joint in a split model experiment, and they were evaluated histologically and histomorphometrically at 15, 30, and 60 days of healing. Results Bone-implant contact (BIC) at the two-implant surfaces was significantly different in favor of the CA surface at 15 days (p = 0.027), while SLActive displayed not significantly higher values at 30 (p = 0.51) and 60 days (p = 0.061). Conclusion Both implant surfaces show an intimate interaction with newly formed bone.

Sinus Membrane Elevation with Heterologous Cortical Lamina: A Randomized Study of a New Surgical Technique for Maxillary Sinus Floor Augmentation without Bone Graft

Background: The aim of this randomized controlled clinical trial was to compare the efficacy of two different techniques for maxillary sinus augmentation using a lateral window approach: Heterologous cortical lamina without any grafting material versus 100% collagenated granular collagen porcine bone. Methods: Twenty-three healthy patients with not relevant past medical history (14 women and 9 men, non-smokers, mean age 52 years, range 48–65 years) were included. In Group I, the sinus was filled with collagen porcine bone (Geno-os, OsteoBiol, Turin, Italy) and a collagen membrane (Evolution, OsteoBiol, Turin, Italy) was used to close the lateral window of the sinus. In Group II, the sinus was treated with heterologous cortical lamina only (Lamina, OsteoBiol, Turin, Italy). Results: There was a statistically significant difference in the surgical time required to complete the augmentation procedures: 18.3 ± 2.1 min for lamina treated sites versus 12.5 ± 3.1 min for porcine bone treated sites. In Group I, the mean volume of the graft was 3101 ± 321 mm3 in the immediate postoperative examination (5–7 days), while after a six-month healing period it was 2716.7 ± 432 mm3. Conclusion: This study demonstrates that the use of heterologous cortical lamina is a valid technique for the mechanical support of sinus membranes resulting in only bone tissue formation and not mixed with the graft. The graft material was biocompatible and not completely resorbed after six months, although the remains were integrated into the bone.

Dental implants displaced into the mandibular corpus: clinical note.

Purpose: Implant migration into the mandibular corpus is a complication reported few times in literature. The aim of study was to describe the clinical characteristics of patients who developed implant displacement into the mandibular corpus, to identify potential risk factors, and to gather information on prevention and treatment of this complication. Methods: We report three cases of implants displaced into the mandibular corpus laterally of mental nerve. Two implants were removed by screwdriver, in only one case an osteotomy was performed with a Piezosurgery device and it was removed with pliers. Results: All patients treated had a trabecular bone not observable with a panoramic radiograph, but they showed in the CBCTs performed after implant migration. In these cases, there is no inflammation or pain, but it is necessary to remove the implant and replace a new implant. None of them had a medical history of osteoporosis. Conclusions: The displacement of implants in the mandibular corpus is not a serious complication, but they must be removed as soon as possible, as the bone healing makes it difficult to remove them later.