Distribution of Trabecular Bone Density in the Maxilla and Mandible.

INTRODUCTION: Implant osseointegration is strongly influenced by the bone quality at the implant insertion site. The present work aims to create distribution diagrams showing the average bone density at each position within the jaws. MATERIALS AND METHODS: Data were retrospectively collected from 4 oral surgeons who sought bone-density measurements during implant placement using a torque-measuring implant micromotor. Statistical analyses were performed to investigate whether bone density correlated with the patients' sex and age and whether the bone-density values at different positions within each arch correlated to each other. RESULTS: Records of 2408 patients and 6060 bone-density readings were retrieved, and density distribution diagrams were created. Density values showed a significant variation within subjects. Within the same jaw, density between adjacent positions showed significant differences. Density at a given position correlated significantly with that at the other positions in most cases. Bone density was significantly lower in women than in men; no significant correlation was found between bone density and the patient age. CONCLUSIONS: Bone density of patients displays significant interindividual variation, thus meaningful assessment must be conducted on a patient-by-patient basis.

Sinus lift with autologous bone alone or in addition to equine bone: an immunohistochemical study in man.

PURPOSE: The aim of the present study was to perform a comparative histological and immunohistochemical evaluation of microvessel density, vascular endothelial growth factor, and nitric oxide synthase (NOS) expression in sinus augmentation using autologous bone alone or in combination with equine bone. MATERIALS AND METHODS: Sixteen patients underwent sinus augmentation with autologous bone and a 50:50 mixture of autologous and equine bone. Control cores were harvested from preexisting nonaugmented bone under the sinus floor. The specimens were processed for immunohistochemistry. RESULTS: The greatest values of microvessel density were found in the sites grafted with autologous bone with significant differences between control versus autologous group (P < 0.01) and control versus autologous + equine group (P < 0.01). The higher and lower intensities of vascular endothelial growth factor and NOS3 expression were prevalent in the sites grafted with autologous bone with significant differences with the controls (P < 0.05). No significant differences (P > 0.05) were found in the NOS1 expression among the groups. CONCLUSION: The results obtained showed that the mixture of autologous and equine bone was biocompatible, and its use was associated with new blood vessels ingrowth during healing, which has been found to be extremely important for bone formation.

Treatment of chemotherapy-induced oral mucositis with light-emitting diode.

OBJECTIVE: The aim of this study was to assess the clinical effectiveness of phototherapy with noncoherent light in the alleviation of chemotherapy-induced mucositis in patients with metastatic cancer. BACKGROUND DATA: Mucositis occurs in more than 40% of chemotherapy-treated patients, significantly reducing the quality of their lives. Many different interventions have been evaluated to reduce oral mucositis. Recently, good results have been achieved by phototherapy with photoradiation, a technique which has virtually no side effects. Some clinical results seem to indicate that also phototherapy through noncoherent light emissions which can be produced by less expensive light sources such as light-emitting diodes (LEDs) may be effective. However, until now, no studies have been available on this subject. METHODS: Twelve patients, aged from 34 to 82, selected on the basis of a diagnosis of chemotherapy-induced oral mucositis, were treated intra-orally through a noncoherent LED emission, wavelength 645 +/- 15 nm, 7.8 mW, fluence 0.99 J/cm(2), three times a day for 1 week. Mucositis was scored daily using the Daily Mucositis Index (DMI), a scale that evaluates the disease evolution through 16 different items. The primary end-point assessed was the time to recovery, from the start of LED treatment, compared to a nonrandomized control group of 12 patients with comparable stomatitis. RESULTS: The median healing time, expressed as the DMI decrease, was 1.7 (range 1-2.8) and, in seven LED-treated patients, was shorter than in the control group. The healing rate (measured as the ratio of the DMIs) increased from 117% to 164%. CONCLUSION: This pilot study shows that LED treatment is safe and capable of reducing the duration of chemotherapy-induced mucositis. This result needs to be confirmed in an adequate phase III study.

Vertical ridge augmentation using a flexible heterologous cortical bone sheet: three-year follow-up.

Rehabilitation of the atrophic alveolar ridge is often problematic. Bone augmentation surgery may be hindered by a lack of surfaces from which blood vessels can spread during the initial stages of bone regeneration. If heterologous biomaterials are used as an alternative to autologous bone grafts, the standard delivery formats-blocks or granules-both have significant limitations. The present study was designed to evaluate the effectiveness of an alternative material, a flexible equine bone sheet, for vertical ridge augmentation. Forty-nine implants were placed in 18 patients whose vertically atrophic maxillary or mandibular ridges were simultaneously augmented with flexible cortical bone sheets derived from equine femurs. After 4 months, the ridge volume for all patients was completely restored, all implants had successfully osseointegrated, and definitive prostheses were placed. These parameters remained unchanged throughout 3 years of follow-up.

Alveolar ridge regeneration with equine spongy bone: a clinical, histological, and immunohistochemical case series.

BACKGROUND: In the case of localized ridge atrophy, a ridge augmentation procedure, with the use of bone substitutes and barrier membranes, may then be necessary. PURPOSE: The aim of the present study was a clinical, histological, and immunohistochemical evaluation of an equine spongy bone in alveolar ridge augmentation procedures. MATERIALS AND METHODS: Five patients showing horizontal mandibular ridge defects participated in this study. A ridge augmentation was performed through an onlay apposition of equine bone covered by a titanium-reinforced membrane. After 6 months of healing, five bone cores from nonaugmented sites (control) and five from augmented sites (test) were retrieved. RESULTS: In test sites, no postoperative complications occurred. Horizontal bone width increased from 24 to 37 mm. In control sites, the newly formed bone represented 33%, and in test sites, 35% of the total area. The mean value of the microvessel density was 25.6 +/- 3.425 per mm(2) in controls, while 33.3 +/- 2.5 vessels per mm(2) in the test sites were found (p < .05). Both groups showed a high intensity (++) of vascular endothelial growth factor expression in the newly formed bone, while a low intensity (+) was found in the mature bone. CONCLUSION: Equine bone appeared to be biocompatible and to be associated with new vessel ingrowth. Within the limits of the small sample size, the present study indicated that equine bone could be used in mandibular ridge augmentations.

Familial hemiplegic migraine mutations increase Ca(2+) influx through single human CaV2.1 channels and decrease maximal CaV2.1 current density in neurons.

Insights into the pathogenesis of migraine with aura may be gained from a study of human Ca(V)2.1 channels containing mutations linked to familial hemiplegic migraine (FHM). Here, we extend the previous single-channel analysis to human Ca(V)2.1 channels containing mutation V1457L. This mutation increased the channel open probability by shifting its activation to more negative voltages and reduced both the unitary conductance and the density of functional channels in the membrane. To investigate the possibility of changes in Ca(V)2.1 function common to all FHM mutations, we calculated the product of single-channel current and open probability as a measure of Ca(2+) influx through single Ca(V)2.1 channels. All five FHM mutants analyzed showed a single-channel Ca(2+) influx larger than wild type in a broad voltage range around the threshold of activation. We also expressed the FHM mutants in cerebellar granule cells from Ca(V)2.1alpha(1)-/- mice rather than HEK293 cells. The FHM mutations invariably led to a decrease of the maximal Ca(V)2.1 current density in neurons. Current densities were similar to wild type at lower voltages because of the negatively shifted activation of FHM mutants. Our data show that mutational changes of functional channel densities can be different in different cell types, and they uncover two functional effects common to all FHM mutations analyzed: increase of single-channel Ca(2+) influx and decrease of maximal Ca(V)2.1 current density in neurons. We discuss the relevance of these findings for the pathogenesis of migraine with aura.