Francesco Polini

Condylar positioning devices for orthognathic surgery: a literature review

In the past few years, many devices have been proposed for preserving the preoperative position of the mandibular condyle during bilateral sagittal split osteotomy. Accurate mandibular condyle repositioning is considered important to obtain a stable skeletal and occlusal result, and to prevent the onset of temporomandibular disorders (TMD). Condylar positioning devices (CPDs) have led to longer operating times, the need to keep intermaxillary fixation as stable as possible during their application, and the need for precision in the construction of the splint or intraoperative wax bite. This study reviews the literature concerning the use of CPDs in orthognathic surgery since 1990 and their application to prevent skeletal instability and contain TMD since 1995. From the studies reviewed, we can conclude that there is no scientific evidence to support the routine use of CPDs in orthognathic surgery.

Piezosurgery: a new method for osteotomies in rhinoplasty.

Two basic techniques for lateral osteotomy have been developed to date; the internal (endonasal) continuous technique and the external (percutaneous) perforating method. Numerous investigators have subjectively reported that the application of the two techniques results in less postoperative ecchymosis and edema compared to the use of other techniques, but an alternative and gentle method for performing lateral osteotomy or bony hump removal has not been proposed yet. The authors present a new soft technique to perform nasal osteotomy in rhinoplasty using piezoelectric ultrasonic vibrations, and emphasize the advantages of this method.

Osteogenesis distraction and platelet‐rich plasma: combined use in restoration of severe atrophic mandible. Long‐term results

OBJECTIVES The purpose of this paper is to report long-term results on the use of autologous bone graft and platelet-rich plasma in alveolar distraction osteogenesis (DO) for restoration of severe atrophic mandible. We tested the efficacy as to reabsorption of bone volume, peri-implant reabsorption, implant survival and success rate. MATERIALS AND METHODS Twelve patients were treated. The surgical procedure consisted in mixing autologous bone, harvested from the iliac crest, with autologous platelet concentrate (APC) and in filling the distraction gap with this graft. After a latency of 15 days, a distraction rate of 0.5 mm/day was followed. After a 60-day period of consolidation, the distraction device was removed and implants were placed simultaneously. The abutment connection was accomplished after 6 months. In addition, every patient was evaluated clinically and radiographically annually for 5 years. RESULTS Planned alveolar height was reached in 11 out of 12 patients. The total number of implants positioned was 47. At the time of implant positioning, the mean decrease of total bone volume was 2.3%. The mean peri-implant resorption was 0.40 mm at the time of abutment connection, 0.61 mm 1 year after implant loading and 1.51 mm after 5 years. After 5 years of follow-up, the mean rate of vertical bone loss was 18.7%. Instead, the implant survival and success rates were 97.9% and 91.5%, respectively. CONCLUSIONS Long-term results allow us to confirm the combination of autologous bone-platelet gel with alveolar DO as an effective and predictable procedure in restoration of severe atrophic mandible.

Piezosurgery: a safe method to perform osteotomies in young children affected by hemifacial microsomia.

Piezosurgery is a new innovating technique used to perform safe and effective osteotomies using piezoelectric ultrasonic vibrations. It was conceived by Tomaso Vercellotti, MD, DDS, and it was first reported for preprosthetic surgery, as alveolar crest expansion, sinus grafting, and, more recently, alveolar distraction. The purpose of this report was to introduce and justify the use of Piezosurgery to perform osteotomies during mandibular distraction in cases of hemifacial microsomia.

Bifunctional Sculpturing of the Bone Graft for 3-Dimensional Augmentation of the Atrophic Posterior Mandible

Short implant procedures may suffer from fixture instability, if incorrectly planned and performed, and from an esthetically compromised rehabilitation, due to increased interarch distance and increased crown-implant ratio. Several procedures have been proposed to achieve alveolar ridge augmentation with different success and complication rates: onlay grafts, alveolar sandwich osteotomies, titanium micromesh, alveolar distraction, and alveolar nerve transposition. The edentulous posterior mandible suffers from the presence of a compact cortical layer, which tends to limit graft osteogenesis, because of a low permeability to the osteogenic elements (microvessels and cells). This report introduces a variant to the endochondral onlay bone graft, in which an external cortical layer is placed above a biologically active core of cancellous bone and platelet-rich plasma. This solution provides easy 3-dimensional conformation of the graft, enhancing its mechanical stability. The presence of the biologically active core provides better vascular support and a valid interface between graft and the osteogenetic cell lines.

Bone Biological Box (BBB): An Evolution of the Sinus Graft

Traditional maxillary sinus lifting and grafting, first described by Boyne and James1 in 1980, is the surgical preprosthetic procedure most commonly used for the rehabilitation of lateral and posterior atrophic maxilla. Although scientific studies have been reported about the use of alloplastic materials for the filling up of maxillary sinus, autologous corticocancellous bone graft remains the principal material for such procedures. It can be easily harvested from calvaria, from mandible, or from iliac crest. This donor site is particularly indicated and effective for the maxillary sinus because of the abundance of tissue that can harvested and because of its richness in precursor cells of bone induction. Even if effective, such a surgical procedure frequently lacks some anatomic, biologic, or technical aspects, such as 1) inadequate real 3-dimensional anatomic restoration of the lateral and posterior maxilla, 2) possible instability of the graft,2 3) maturation of the engaged bone and consequent reabsorption,3 4) difficult manageability of the graft, and 5), in the presence of a conspicuous perforation of the sinus membrane, it is possible only to perform a blockshaped graft (with consequent reduced adaptability to the sinus floor4) or to suspend surgery. To overcome such difficulties and problems, the authors introduce and report a technical variation of classic procedure, called bone biological box (BBB), as an evolution of the sinus traditional grafting. With the term “bone,” the authors want to emphasize the importance of the autologous bony tissue. The term “biological” means that the procedure is able to enhance the properties of bone induction, caused by the enrichment with platelet-derived growth factors. Finally, the term “box” indicates that a new anatomic region with rigid side walls is created to contain the graft, obtaining a very stable 3-dimensional reconstruction.

Disfiguring Nasal Metastasis from Colorectal Adenocarcinoma: A Case Report

In May 1996, a 56-year-old woman underwent a sigmorectal anterior resection in order to treat a C1 G2 sigmorectal carcinoma. During postsurgical follow-up synchronous liver metastasis were found, involving III, V, VI, and VII liver segments. In November 1996, the patient was hospitalized and underwent a surgical excision of liver metastasis. Postsurgical examination did not find curing of tumor disease during the next 2 years. In November 1998, the patient was admitted again. Metachronous metastasis to the left liver and lung was confirmed by computed tomography (CT) and nuclear magnetic resonance scans. No lesions were found along the surgical anastomosis. Objective patient examination revealed a small lesion of the right nasal vestibule, which the patient previously perceived only as a little swelling to the touch without any subjective symptoms. This mass was 1 cm wide, covered with healthy skin and fixed to the deep tissue. In order to clarify the nature and origin of the lesion, a transnasal biopsy was performed. Histologic report demonstrated infiltration by colorectal adenocarcinoma constant with vascular invasion. Since February 1999, the patient received 7000 cGy of external beam radiation to the nose in 5 weeks and underwent 1 chemotherapy cycle. When the patient was seen for clinical examination 2 months later, she showed an huge deforming swelling (Fig 1A) that occupied the entire right half of her face, with massive involvement of the maxillary sinus, orbit, and oral cavity, diverting the tongue laterally. CT scan (Fig 1B) showed an enormous mass that occupied oral cavity, orbit, maxillary, and ethmoidal sinuses, reaching also the sphenoidal sinus and skull base. The patient died 1 month later. DISCUSSION