Implant-supported single tooth restoration in the aesthetic zone: transmucosal and submerged healing provide similar outcome when simultaneous bone augmentation is needed

AIM: The aim of this study was to compare the clinical outcomes after 2 years with bone level implants placed to restore a single missing teeth that needed simultaneous augmentation and were treated with a transmucosal or submerged approach. METHODS: This study analyzed a subset of patients included in an ongoing prospective multicenter randomized clinical trial (RCT) involving12 centers where patients were to be followed-up to 5 years after loading. Of the 120 implants that were placed in the original study, and randomly assigned to submerged or non-submerged healing, 52 needed simultaneous augmentation (28 women patients and 24 men patients, between 23 and 78 years of age). Twenty-seven of them received implants with submerged healing (AuS), while in 25 patients the implants were inserted with a non-submerged protocol (AuNS). At the 2-year follow-up visit, radiographic crestal bone level changes were recorded as well as soft tissue parameters included Pocket probing depth (PPD), bleeding on probing (BoP) and clinical attachment level (CAL) at teeth adjacent to the implant site. RESULTS: After 2 years a small amount of bone resorption was found in both groups (0.37 ± 0.49 mm in the AuS group and 0.54 ± 0.76 in the AuNS group; P < 0.001). There was no statistically significant difference between AuS Group and AuNS group for PPD (2.5 vs. 2.4 mm), BOP (BOP + sites: 8.8% vs. 11.5%) and CAL (2.8 vs. 2.4 mm) at the 2-year follow-up visit. CONCLUSIONS: When a single implant is placed in the aesthetic zone in conjunction with bone augmentation for a moderate peri-implant defect, submerged and transmucosal healing determine similar outcome, hence there is no need to submerge an implant in this given clinical situation.

A Double-Blind Randomized Controlled Trial (RCT) of Titanium-13Zirconium versus Titanium Grade IV Small-Diameter Bone Level Implants in Edentulous Mandibles - Results from a 1-Year Observation Period

Background: The use of endosseous dental implants has become common practice for the rehabilitation of edentulous patients, and a two-implant overdenture has been recommended as the standard of care. The use of small-diameter implants may extend treatment options and reduce the necessity for bone augmentation. However, the mechanical strength of titanium is limited, so titanium alloys with greater tensile and fatigue strength may be preferable. Purpose: This randomized, controlled, double-blind, multicenter study investigated in a split-mouth model whether small-diameter implants made from Titanium-13Zirconium alloy (TiZr, Roxolid™) perform at least as well as Titanium Grade IV implants. Methods and Materials: Patients with an edentulous mandible received one TiZr and one Ti Grade IV small-diameter bone level implant (3.3 mm, SLActive®) in the interforaminal region. The site distribution was randomized and double-blinded. Outcome measures included change in radiological peri-implant bone level from surgery to 12 months post-insertion (primary), implant survival, success, soft tissue conditions, and safety (secondary). Results: Of 91 treated patients, 87 were available for the 12-month follow-up. Peri-implant bone level change (-0.3 ± 0.5 mm vs -0.3 ± 0.6 mm), plaque, and sulcus bleeding indices were not significantly different between TiZr and Ti Grade IV implants. Implant survival rates were 98.9 percent and 97.8 percent, success rates were 96.6 percent and 94.4 percent, respectively. Nineteen minor and no serious adverse events were related to the study devices. Conclusion: This study confirms that TiZr small-diameter bone level implants provide at least the same outcomes after 12 months as Ti Grade IV bone level implants. The improved mechanical properties of TiZr implants may extend implant therapy to more challenging clinical situations.

Hindfoot varus and neurologic disorders

Muscle imbalance from numerous underlying neurologic disorders can cause dynamic and static hindfoot varus deformity. Most etiologies are congenital, and therefore affect bone morphology and the shape of the foot during growth. Weak and strong muscle groups, bone deformity, and soft-tissue contractures have to be carefully assessed and considered for successful management. Because of the variety of the etiologies and the differences in presentation, treatment decisions in varus hindfoot caused by neurologic disorders must be individualized. Deformity correction includes release of soft tissue contractures, osteotomies and arthrodeses, and tenotomies or tendon transfers to balance muscle strength and prevent recurrence. To decrease elevated anteromedial ankle joint contact stress and provide lateral hindfoot stability during the entire gait cycle, the goal of static and dynamic hindfoot varus realignment is to fully correct all components of the deformity, but particularly the varus tilt of the talus.

Effect of a plasmaelectrolytic coating on the strength retention of in vivo and in vitro degraded magnesium implants

The strength decrease in magnesium implants was studied in vitro and in vivo, with and without a protective plasmaelectrolytic coating. In vivo, degradation was examined by implanting rectangular plates on top of the nasal bone of miniature pigs. The presence of gas pockets in the soft tissue surrounding the implants was evaluated with intermediate X-rays and computed X-ray tomography scans before euthanasia. After 12 and 24weeks of in vivo degradation, the large rectangular plates were removed and mechanically tested in three-point bending. In vitro, identical plates were immersed in simulated body fluid for 4, 8 and 12weeks. In vitro and in vivo results showed that onset of gas release can be delayed by the plasmaelectrolytic coating. Mass loss and strength retention during in vivo degradation is about four times slower than during in vitro degradation for the chosen test conditions. Despite the slow degradation of the investigated WE43 alloy, the occurrence of gas pockets could not be completely avoided. Nevertheless, uniformity of degradation and reliable strength retention make this alloy a prime candidate for the use of magnesium in cranio-maxillofacial surgery.

Clinical and radiographic outcome of dental implants supporting fixed prostheses: the relevance of cortical bone formation

To evaluate the hard and the soft tissue parameters around implants supporting fixed prostheses over a period of 5 years and the possible association to the increase in periimplant bone density (IPBD).

Nanoparticle-based test measures overall propensity for calcification in serum

Vascular and soft tissue calcification contributes to cardiovascular morbidity and mortality in both the general population and CKD. Because calcium and phosphate serum concentrations are near supersaturation, the balance of inhibitors and promoters critically influences the development of calcification. An assay that measures the overall propensity for calcification to occur in serum may have clinical use. Here, we describe a nanoparticle-based assay that detects, in the presence of artificially elevated calcium and phosphate concentrations, the spontaneous transformation of spherical colloidal primary calciprotein particles (CPPs) to elongate crystalline secondary CPPs. We used characteristics of this transition to describe the intrinsic capacity of serum to inhibit the precipitation of calcium and phosphate. Using this assay, we found that both the sera of mice deficient in fetuin-A, a serum protein that inhibits calcification, and the sera of patients on hemodialysis have reduced intrinsic properties to inhibit calcification. In summary, we developed a nanoparticle-based test that measures the overall propensity for calcification in serum. The clinical use of the test requires evaluation in a prospective study.

Diagnosis and treatment of mucormycosis in patients with hematological malignancies: guidelines from the 3rd European Conference on Infections in Leukemia (ECIL 3)

Mucormycosis is an emerging cause of infectious morbidity and mortality in patients with hematologic malignancies. However, there are no recommendations to guide diagnosis and management. The European Conference on Infections in Leukemia assigned experts in hematology and infectious diseases to develop evidence-based recommendations for the diagnosis and treatment of mucormycosis. The guidelines were developed using the evidence criteria set forth by the American Infectious Diseases Society and the key recommendations are summarized here. In the absence of validated biomarkers, the diagnosis of mucormycosis relies on histology and/or detection of the organism by culture from involved sites with identification of the isolate at the species level (no grading). Antifungal chemotherapy, control of the underlying predisposing condition, and surgery are the cornerstones of management (level A II). Options for first-line chemotherapy of mucormycosis include liposomal amphotericin B and amphotericin B lipid complex (level B II). Posaconazole and combination therapy of liposomal amphotericin B or amphotericin B lipid complex with caspofungin are the options for second line-treatment (level B II). Surgery is recommended for rhinocerebral and skin and soft tissue disease (level A II). Reversal of underlying risk factors (diabetes control, reversal of neutropenia, discontinuation/taper of glucocorticosteroids, reduction of immunosuppressants, discontinuation of deferroxamine) is important in the treatment of mucormycosis (level A II). The duration of antifungal chemotherapy is not defined but guided by the resolution of all associated symptoms and findings (no grading). Maintenance therapy/secondary prophylaxis must be considered in persistently immunocompromised patients (no grading).

Technetium-99m-HDP uptake characteristics in equine fractures: a retrospective study

Bone scintigraphy is a very sensitive diagnostic tool to detect elevated bone metabolism. In cases of fractures and fissure fractures, the radiopharmaceutical uptake in the bone is said to be increased within a few hours after the injury. In this retrospective study, the scintigraphic uptake characteristics at the fracture site of 36 horses with radiographically confirmed fractures or fissure fractures were evaluated. Uptake ratios between the fracture region and adjacent normal bone or soft tissue activity respectively were calculated and compared to different anamnestic and radiographic data. The overall sensitivity of bone scintigraphy was 94.4% (34 positive cases out of 36). In the 36 horses, no correlation between the age of the fracture and the radiopharmaceutical uptake was found. However, there seems to be a lack of sensitivity in early detection of equine pelvic fractures when a standing bone scintigraphy examination protocol is used.

Efficiency of recombinant human TNF in human cancer therapy

Recombinant human tumour necrosis factor (TNF) has a selective effect on angiogenic vessels in tumours. Given that it induces vasoplegia, its clinical use has been limited to administration through isolated limb perfusion (ILP) for regionally advanced melanomas and soft tissue sarcomas of the limbs. When combined with the alkylating agent melphalan, a single ILP produces a very high objective response rate. In melanoma, the complete response (CR) rate is around 80% and the overall objective response rate greater than 90%. In soft tissue sarcomas that are inextirpable, ILP is a neoadjuvant treatment resulting in limb salvage in 80% of the cases. The CR rate averages 20% and the objective response rate is around 80%. The mode of action of TNF-based ILP involves two distinct and successive effects on the tumour-associated vasculature: first, an increase in endothelium permeability leading to improved chemotherapy penetration within the tumour tissue, and second, a selective killing of angiogenic endothelial cells resulting in tumour vessel destruction. The mechanism whereby these events occur involves rapid (of the order of minutes) perturbation of cell-cell adhesive junctions and inhibition of alphavbeta3 integrin signalling in tumour-associated vessels, followed by massive death of endothelial cells and tumour vascular collapse 24 hours later. New, promising approaches for the systemic use of TNF in cancer therapy include TNF targeting by means of single chain antibodies or endothelial cell ligands, or combined administration with drugs perturbing integrin-dependent signalling and sensitizing angiogenic endothelial cells to TNF-induced death.

Histomorphologic evaluation of extracorporeal shock wave therapy of the fourth metatarsal bone and the origin of the suspensory ligament in horses without lameness

OBJECTIVE: To determine via histologic examination and scintigraphy the effect of focused extracorporeal shock wave therapy (ESWT) on normal bone and the bone-ligament interface in horses. ANIMALS: 6 horses without lameness. PROCEDURE: Origins of the suspensory ligament at the metacarpus (35-mm probe depth) and fourth metatarsal bone (5-mm probe depth) were treated twice (days 0 and 16) with 2,000 shocks (energy flux density, 0.15 mJ/mm2). One forelimb and 1 hind limb were randomly treated, and the contralateral limbs served as nontreated controls. Bone scans were performed on days -1 (before ESWT), 3, 16, and 19. Histomorphologic studies of control and treated tissues were performed on day 30. RESULTS: ESWT significantly increased the number of osteoblasts but caused no damage to associated soft tissue structures and did not induce cortical microfractures. A significant correlation between osteoblast numbers and radiopharmaceutical uptake was noticed on lateral views of the hind limb on days 3 and 16 and on caudal views of the forelimb on day 3. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that ESWT has the potential to increase osteoblast numbers in horses. The correlation between increased osteoblast numbers and radio-pharmaceutical uptake 3 days and 16 days after the first ESWT suggested that stimulation of osteogenesis occurred soon after ESWT. No damage to bone or the bone-ligament interface should occur at the settings used in this study, and ESWT can therefore be administered safely in horses.

[Disorders of the origin of the suspensory ligament in the horse: a diagnostic challenge]

Lameness in horses due to pain originating from the proximal metacarpal/metatarsal region remains a diagnostic challenge. In cases of obvious lameness the pain can be localised to this region by diagnostic anaesthesia. Because a variety of disorders can cause lameness in this region different imaging modalities including radiography, ultrasonography and scintigraphy should be used to arrive at an accurate diagnosis. Even though a precise anatomic-pathologic diagnosis can still be an enigma, because not only bone and joints, but also soft tissue structures including the proximal suspensory ligament, its origin at the proximal metacarpus/ metatarsus, its fascia, the superficial fascia, as well as the intermetacarpal/metatarsal ligaments, the accessory ligament of the deep digital flexor tendon and both digital flexor tendons may be involved. Magnet resonance tomography (MRT) shows a high diagnostic sensitivity in imaging soft tissue structures and bone. In horses MRT is still at the beginning. The MRT appearance of the proximal metacarpal/metatarsal region has not yet been evaluated in detail and there are only few anatomic studies of the origin of the suspensory ligament in horses. The first experiences showed, that more gross and histologic examinations are necessary to fully interpret MRT-images and to differentiate pathologic alterations from clinically not relevant variations.

Evaluation of late results in breast reconstruction by latissimus dorsi flap and prosthesis implantation

BACKGROUND: Breast reconstruction by latissimus dorsi myocutaneous flap in combination with a prosthesis is a widely used, well-established procedure. Short- and medium-term evaluation after this procedure is well described in the literature, but there have been no evaluations of the late course (over 10 years) published until now. METHODS: In a retrospective study, 68 patients operated on by means of this technique at the authors' institution from 1981 to 1993 resulting in a minimal follow-up of 10 years were included. Patients were invited to an interrogation, clinical examination, and photographic documentation (n = 51). Incidence of late flap or prosthesis-related complications, number of and indications for corrective procedures, and the correlation of the patients' subjective judgment and objective results in the late course have been the main interest of the authors' survey. RESULTS: The authors found that 50 percent of the patients needed a late reoperation for change or removal of the prosthesis. Seven (10 percent) of 68 patients needed a definitive removal of the implant in the late course. Assessment of the photographic documentation of the late result by four nonprofessionals showed that the objective aesthetic results of a considerable number of the authors' reconstructions were not sufficient. CONCLUSION: The procedure combines two basic techniques of reconstructive surgery, the soft-tissue restoration by a pedicled flap as the autologous reconstructive component and the volume reconstruction by prosthesis. Therefore, these patients are subject to a cumulation of the basic morbidity of the two techniques. The authors conclude that the indication for this procedure should be restricted to patients not qualifying for "pure" reconstructive techniques.

[Medium-term results after m. vastus medialis obliquus-plasty for lateral patellar dislocation]

Progressive retropatellar arthrosis is often seen in dated rigid distal realignment (i.e. osteotomy of tuberositas) at long-term follow-ups. Therefore, operations for lateral dislocation of the patella are still discussed controversially. Dynamic, proximal realignments seem to have lower rates of arthrosis but higher rates of redislocation. Recently, in anatomic and biomechanic studies, the m. vastus medialis obliquus (vmo) was found to be one of the most important proximal restraints to lateral dislocation of the patella.A total of 28 patients (mean age 21.5 years) were treated between 1994 and 2003 with a plasty of the vmo for lateral patellar dislocation. The technique was performed for most etiologies of femoropatellar instability.For this proximal soft tissue technique, the muscle tendon is detached from its patellar insertion. Subsequently, the tendon is reinserted at the patella 10-15 mm more distally and fixed with Mitek anchors. Full weight bearing in extension is possible immediately after surgery. An active vastus medialis training is started after 6 weeks.Of the patients, 27 were evaluated clinically and radiologically in 2004 (a mean of 5 years postoperatively). A total of 83% of the patients estimated the result to be good or excellent, 10% were satisfied and 7% were discontent. The mean Lysholm-Knee-Score was 83.1 points. Two patients suffered a patella redislocation (7%). A statistically significant improvement of the congruence angle was noted in the radiographs, even in medium-term controls. In 89% of the cases no or only little retropatellar arthrosis was observed. These 5 year results are comparable to those of other techniques for distal or proximal realignments. The rate of redislocation was below average. Compared to the rate of retropatellar arthrosis in long-term results of rigid distal realignment, our patients demonstrated a relative low rate after 5 years. We attribute this to the minimal interference in physiological joint mechanics and to the restored anatomy. In terms of future long-term results, our findings are promising. The idea of a proximal dynamic stabilization and the causal operative approach at the origin of pathology using vmo-plasty was confirmed in recent anatomic and biomechanic studies. Over or under correction of soft tissues could be adapted. More rigid techniques of distal realignment do not allow an adaptation to this extent and can lead to prearthrotic hyperpression in the medial femoropatellar and femorotibial joints.

VIRTOPSY: minimally invasive, imaging-guided virtual autopsy

Invasive "body-opening" autopsy represents the traditional means of postmortem investigation in humans. However, modern cross-sectional imaging techniques can supplement and may even partially replace traditional autopsy. Computed tomography (CT) is the imaging modality of choice for two- and three-dimensional documentation and analysis of autopsy findings including fracture systems, pathologic gas collections (eg, air embolism, subcutaneous emphysema after trauma, hyperbaric trauma, decomposition effects), and gross tissue injury. Various postprocessing techniques can provide strong forensic evidence for use in legal proceedings. Magnetic resonance (MR) imaging has had a greater impact in demonstrating soft-tissue injury, organ trauma, and nontraumatic conditions. However, the differences in morphologic features and signal intensity characteristics seen at antemortem versus postmortem MR imaging have not yet been studied systematically. The documentation and analysis of postmortem findings with CT and MR imaging and postprocessing techniques ("virtopsy") is investigator independent, objective, and noninvasive and will lead to qualitative improvements in forensic pathologic investigation. Future applications of this approach include the assessment of morbidity and mortality in the general population and, perhaps, routine screening of bodies prior to burial.

Oral mucosal lesions diagnosed in a stomatology service. An examination of clinico-pathological findings from the year 2003

During 2003, a total of 258 new patients with oral soft tissue lesions were admitted at the Stomatology Service of the Department of Oral Surgery and Stomatology at the University of Berne. For the present study, 185 patients with clinically and histopathologically verified diagnoses were included. The following data was collected: prevalence of oral mucosal lesions, distribution of benign, precancerous and malign lesions in different age groups, and the concordance of the referral with the working diagnosis at the Stomatology Service. The most frequent pathological soft tissue findings were fibrous hyperplasias (n = 44) and oral lichen planus (n = 30). Precancerous lesions were present in 41 cases (30 patients with oral lichen planus, eleven oral leukoplakias), and ten patients had oral malignomas. Most lesions were found in patients between the age of 40 and 60 years. The referral diagnosis concurred in 36.6% (n = 67) of the cases with the definite diagnosis before initiation of treatment, the working diagnosis in 70% (n = 128) of the cases. Therefore, it can be concluded that a specialised Stomatology Service serves as a center of competence due to large numbers of patients/cases seen and treated, and the resulting high level of clinical experience of the staff. Moreover, it is important in the primary diagnosis of oral squamous cell carcinoma, in collaboration with the referring dentist in private practice.