Are there specific indications for the different alveolar bone augmentation procedures for implant placement? A systematic review.

Bone resorption following tooth loss often interferes with dental implant placement in a desired position, and requires additional bone augmentation procedures. Many techniques have been described to augment and reconstruct alveolar ridge width and height. The aim of this study was to systemically review whether there is evidence to provide indications for the various bone augmentation procedures based on defect dimension and type. An electronic search of the Medline database and Cochrane library, complemented by a manual search, was performed. Inclusion criteria for partial edentulism were: clinical trials on bone augmentation procedures in preparation or at the time of implant placement, reporting preoperative and postoperative dimensions of the ridge. For edentulous patients, studies were included when providing the data on ridge and defect description, or the amount of augmentation achieved. The search yielded 53 publications for partially edentulous patients and 15 publications for edentulous patients. The literature provides evidence that dehiscence and fenestrations can be treated successfully with guided bone regeneration (GBR) at the time of implant placement (mean implant survival rate (MISR) 92.2%, mean complication rate (MCR) 4.99%). In partially edentulous ridges, when a horizontal defect is present, procedures such as staged GBR (MISR 100%, MCR 11.9%), bone block grafts (MISR 98.4%, MCR 6.3%), and ridge expansion/splitting (MISR 97.4%, MCR 6.8%) have proved to be effective. Vertical defects can be treated with simultaneous and staged GBR (MISR 98.9%, MCR 13.1% and MISR 100%, MCR 6.95%, respectively), bone block grafts (MISR 96.3%, MCR 8.1%), and distraction osteogenesis (MISR 98.2%, MCR 22.4%). In edentulous patients, there is evidence that bone block grafts can be used (MISR 87.75%), and that Le Fort I osteotomies can be applied (MISR 87.9%), but associated with a high complication rate. The objective of extracting specific indications for each procedure could not be fully achieved due to the heterogeneity of the studies available. Further studies on bone augmentation procedures should report precise preoperative and postoperative measurements to enable a more exact analysis of the augmentation procedure, as well as to provide the clinician with the rationale for choosing the most indicated surgical approach.

Inlay-onlay grafting for three-dimensional reconstruction of the posterior atrophic maxilla with mandibular bone.

This prospective study describes and evaluates a surgical approach for 3D reconstruction of the posterior maxilla with autogenous mandibular bone in 16 patients (mean age 51 years). Bone blocks were harvested from the mandible and used as lateral or vertical block grafts (onlay); they were also partially milled and used for sinus elevation (inlay). In 4 cases, anorganic bovine bone was added at the periphery of the blocks. 4 months after grafting, implants were placed in a second operation and loaded after 12 weeks. Lateral and vertical augmentations were measured immediately after grafting and at re-entry for implant placement. Mean lateral augmentation performed was 5.5mm, reduced to 4.3mm (p<0.01) after 4 months' healing. Mean vertical augmentation was 3.2mm, reduced to 2.1mm (p<0.01) after healing. The amounts of lateral and vertical graft resorption were similar (1.2mm vs. 1.1mm) but were different when compared with the original graft (22% vs. 34%). 49 implants were placed 4 months after grafting. Implant parameters were evaluated after 32-48 months follow up and demonstrated 100% survival rates. The use of mandibular bone grafts for 3D augmentation of the posterior maxilla has shown good results and minor complications.

Subcutaneous phaeohyphomycosis caused by Phaeoacremonium parasiticum in a renal transplant patient.

A 49-year-old renally transplanted man, under a five-year course of immunosuppressive therapy with prednisone and cyclosporine A, experienced a subcutaneous phaeohyphomycosis caused by Phaeoacremonium parasiticum. The clinical presentation consisted of impressive, large, inflammatory and draining cystic tumors on the left foot that had been present for one year. A significant improvement was obtained with itraconazole plus intralesional injection with amphotericin B. Drug interaction was observed between itraconazole and cyclosporine A causing a severe hypertensive crisis and requiring a temporary sharp reduction in cyclosporine administration. Subcutaneous phaeohyphomycosis caused by P. parasiticum is uncommon among major organ transplant patients but several cases have previously been published and some patterns are emerging, e.g., limbs are generally involved but no known traumatic event has preceded lesion development. The identification of the case isolate was confirmed using a recently published online system based in part on beta-tubulin sequence comparison.

Synovium as a source of increased amino-terminal parathyroid hormone-related protein expression in rheumatoid arthritis. A possible role for locally produced parathyroid hormone-related protein in the pathogenesis of rheumatoid arthritis.

Proinflammatory cytokines, including tumor necrosis factor (TNF) and interleukin 1 (IL-1), mediate the joint destruction that characterizes rheumatoid arthritis (RA). Previous studies have shown that parathyroid hormone-related protein (PTHrP) is a member of the cascade of proinflammatory cytokines induced in parenchymal organs during lethal endotoxemia. To test the hypothesis that NH2-terminal PTHrP, a potent bone resorbing agent, could also be a member of the synovial cascade of tissue-destructive cytokines whose expression is induced in RA, PTHrP expression was examined in synovium and synoviocytes obtained from patients with RA and osteoarthritis (OA). PTHrP production, as determined by measurement of immunoreactive PTHrP(1-86) in tissue explant supernatants, was increased 10-fold in RA versus OA synovial tissue. Synovial lining cells and fibroblast-like cells within the pannus expressed both PTHrP and the PTH/PTHrP receptor, findings that were confirmed by in vitro studies of cultured synoviocytes. TNF-alpha and IL-1beta stimulated PTHrP expression in synoviocytes, while dexamethasone and interferon-gamma, agents with some therapeutic efficacy in the treatment of RA, inhibited PTHrP release. Treatment of synoviocytes with PTHrP(1-34) stimulated IL-6 secretion. These results suggest that proinflammatory cytokine-stimulated production of NH2-terminal PTHrP by synovial tissue directly invading cartilage and bone in RA may mediate joint destruction through direct effects on cartilage or bone, or, indirectly, via the induction of mediators of bone resorption in the tumor-like synovium.

[The morphology of the base of the cranium in prognathism. A cephalometric study of adult patients]. / La morfologia della base cranica nel progenismo. Studio cefalometrico su pazienti adulti.

The cranial base of 60 adults affected by mandibular prognathism was studied with the aid of a computerized cephalometric analysis. The means and standard deviations of the values measured on the sample where compared with the cephalometric standards of the University of Michigan. The studied sample showed a significant reduction in length of the floor of the anterior cranial fossa, the cranial base angle showed no deviation from the control but the whole cranial base was backward and upward rotated in relation to the Frankfurt plane. The cranial base morphology was similar in patients with or without maxillary retrusion. The data in our possession may indicate that mid-facial sagittal growth in patients affected by mandibular prognathism is somehow impaired by altered cranial base growth. In any case the sagittal projection of the frontal and nasal bones appears to be reduced in our patients and this data must be kept in mind when studying these patients with the aid of cephalometry.

[Functional dynamics of the TMJ. Importance of the lateral capsular ligament]. / Dinamica funzionale dell'ATM. Importanza del legamento capsulare laterale.

On the base of some papers previously published on the anatomy and physiology of the Tmj the Authors have studied the intracapsular dynamics of the cranio mandibular articulation. The intracapsular movements are guided by some biomechanical restrictions that have been cautiously studied and analized. The biological advantages of the presence of the meniscus between the two articular surfaces is clearly stated. The role of the lateral capsular ligament in stabilizing the disk over the condyle head is clearly demonstrated on the base of previous studies both on the microscopic and macroscopic anatomy of the ligament and the capsule. According to the Authors the disk is stabilized over the condyle head by the lateral capsular ligament, the temporomandibular ligament and by the histological structure of the meniscus that permits its compression and distorsion during the mandibular movements. The disk distorsion increases the anatomical correspondence between the intracapsular structures.

Condylar hyperplasia: cephalometric study, treatment planning, and surgical correction (our experience).

We have studied and treated 12 selected cases of condylar hyperplasia. All of our cases showed no clinical or instrumental sign of still active hyperplastic growth of the mandibular condyle. The cephalometric studies demonstrated in all cases a pathologic vertical growth of the maxilla interesting the posterior segments on the same side of the hyperplastic condyle. We decided not to perform a condylectomy because we did not expect the condyle to grow any further. The treatment consisted of Le Fort I osteotomies and sagittal split osteotomies sometimes in combination with genioplasty and mandibular remodeling. The mandibular physiologic movements were preserved in all cases.

[The use of an intermediate splint in surgical correction of facial asymmetry]. / L'utilizzo di uno splint intermedio nella correzione chirurgica delle asimmetrie facciali.

Facial asymmetries often presents maxillary and mandibular involvement. The surgical repositioning of the maxilla in three planes of space is a must that guarantees the achievement of good function and skeletal symmetry. The Authors, looking for a more precise and correct way to quantify the maxillary movements, suggest to use an acrylic splint that guarantees the reproduction of the skeletal movements decided during the treatment planning procedures. The technique proposed, that is based on a very precise work during the model surgery, offers, as reported by the authors, good results and a significant reduction in surgery time.

[Hemifacial microsomia and mandibulofacial dysostosis: cephalometric study]. / Microsomia emifacciale e disostosi mandibulo-facciale: studio cefalometrico.

This article describes the dental skeletal and aesthetic features that characterize Mandibulo-facial dysostosis and Hemifacial microsomia. Each patient has been studied with three different cephalometric analysis in the laterolateral projection. The data are fully reported and discussed. Particular emphasis is put on the differences and correlations between the two syndromes from the point of view both of morphology and physiopathology.