Measurement of the Interantral Bone in Implant Dentistry Using Panoramic Radiography and Cone Beam Computed Tomography: A Human Radiographic Study.

OBJECTIVE: To analyse the dimensions of interantral bone available for dental implant placement in the fully edentulous maxilla. METHODS: Interantral bone height (IBH) was measured using panoramic radiography and computed tomography (CT). Interantral bone width (IBW) was measured by means of CT. RESULTS: The difference between both imaging methods in IBH assessment was highly statistically significant (p < 0.001) in the canine area, whereas in other areas it was found not to be significant. Measured in the CT scans, bone is significantly higher in the canine area compared to the area of central and lateral incisors (p < 0.001). Significant variations in IBW were found in all three locations: bone in the central incisor area is the widest, in the area of the lateral incisor, the narrowest (p < 0.001). CONCLUSIONS: Panoramic radiography is a sufficiently accurate method for IBH imaging in the incisor area, but not in the canine area.

[Histologic findings in subantral augmentation (sinus lift)]. / Histologické nálezy u subantrální augmentace (sinus lift).

Subantral augmentation (sinus lift) is used to increase alveolar bone mass of lateral maxilla in order to insert dental implants. In addition to the autogenous bone several foreign materials can be used for augmentation and they can replace the autogenous bone to some extent. Histological findings in specimens taken nine months after augmentation with the autogenous bone, deproteinised bovine bone (Bio-Oss) and beta-tricalcium phosphate (Cerasorb) are presented. In all cases a new bone formation around the augmentation material was seen. The new bone was deposited predominantly on its surface. In cases with Cerasorb the new bone formation was observed within the porous granules, too. From the obtained results it can be concluded, that the main osteogenetic mechanism in the examined augmentation materials was osteoconduction. The biocompatibility of the used augmentation materials was evidenced by an absence of giant cell granulomatous reaction and of marked inflammatory infiltrate.

The use of oxidized regenerated cellulose (surgicel) in closing Schneiderian membrane tears during the sinus lift procedure / El uso de celulosa oxidada regenerada (Surgicel®) para cerrar las roturas de la membrana de Schneider durante el procedimiento quirúrgico del levantamiento del seno

During the sinus lift procedure, undesirable perforations of the Schneiderian membrane can occur in up to 58of cases. Several methods for their closing exist. This article presents a method of covering the perforation with a strip of oxidized regenerated cellulose (Surgicel). One or two layers of material swell after being saturated with blood, turning into a gelatinous mass and forming a tight and mechanically resistant seal. This simple method has been successfully tested on 223 perforations of the Schneiderian membrane that occurred over a period of 58 months.

Durante el procedimiento quirúrgico del levantamiento del seno, pueden producirse perforaciones indeseables de la membrana sinusal, hasta en el 58% de los casos. Existen varios métodos de cierre. Este artículo presenta un método para cubrir la perforación con una lámina de celulosa oxidada regenerada (Surgicel®). Una o dos capas del material se hinchan luego de ser saturadas con sangre, transformándose en una masa gelatinosa, y formando así un sello consistente y mecánicamente resistente. Este método simple ha sido probado con éxito en 223 perforaciones de la membrana de Schneider ocurridas en un período de 58 meses.

A six-year study of hydroxyapatite-coated root-form dental implants / Un estudio de seis años sobre implantes dentales de raíz con recubrimiento de hidroxiapatita

BACKGROUND: The effect of hydroxyapatite coating of dental implants is controversial. The long-term fate of hydroxyapatite-coated implants has been the subject of some criticism. PURPOSE: The aim of this retrospective study was to assess the clinical outcome of hydroxyapatite-coated cylindrical root-form endosseous Impladent dental implants (LASAK Ltd, Prague, Czech Republic) during a six-year course. METHODS: Three-hundred and ninety-one consecutively placed implants were used in 169 patients and followed for four to six years. Interval and cumulative success of implants and prostheses survival was tabulated. Marginal bone loss was measured RESULTS: Of the total number of implants, 98.5achieved initial osseointegration. The cumulative success was 98.3after one year, 97.0after three years, 92.8after five years and 90.4after six years. The prostheses survival at the end of the study was 100for fixed bridges totally supported by implants, 96.5for fixed bridges with combined implant and tooth support, 94.2for single crowns, 90.9for mandibular overdentures and 81.3for maxillary overdentures. Marginal bone loss averaged 2.4 +/- 0.8 mm at the end of five years. CONCLUSION: The success rate of the investigated hydroxyapatite-coated implants was comparable with the data presented in the literature and with the results of the similar implants without hydroxyapatite-coating. However, the marginal bone loss was of interest. Longer monitoring of the implants is necessary.

ANTECEDENTES: El efecto del recubrimiento de los implantes dentales con hidroxiapatita es un asunto controversial. El destino a largo plazo de los implantes recubiertos con hidroxiapatita ha sido objeto de críticas. PROPÓSITO: El objetivo de este estudio retrospectivo fue evaluar los resultados clínicos de los implantes dentales endo-óseos de raíz con recubrimiento de hidroxiapatita de la marca Impladent (LASAK Ltd., Praga, República Checa), durante el transcurso de seis años. MÉTODOS: Un número de 391 implantes colocados consecutivamente, fueron usados en 169 pacientes, y sujetos a seguimiento por un período de 4 a 6 años. Se tabuló el éxito de lo implantes – por intervalos y de forma cumulativa – así como la supervivencia de las prótesis. Se midió la pérdida de hueso marginal. RESULTADOS: El 98.5% de los implantes alcanzó óseo-integración en la fase inicial. El éxito cumulativo fue de 98.3% después de un año, 97.0% después de tres años, 92.8% luego de cinco años, y 90.4% tras seis años. La supervivencia de las prótesis al final del estudio fue de 100% para puentes fijos soportados totalmente por implantes, 96.5% para puentes fijos con combinación de soporte sobre dientes e implantes, 94.2% para coronas solas, 90.9% para sobredentaduras mandibulares, y 81.3% para sobredentaduras maxilares. La pérdida marginal de hueso tuvo un promedio de 2.4 ± 0.8 mm al final de los cinco años.CONCLUSIÓN: La tasa de éxito de los implantes recubiertos con HA investigados, resultó comparable a los datos presentados en la literatura, y a los resultados de implantes similares sin revestimiento de HA. Sin embargo, la pérdida marginal de hueso fue una alerta: se necesita monitorear los implantes por un período más largo de tiempo.

A six-year study of hydroxyapatite-coated root-form dental implants.

BACKGROUND: The effect of hydroxyapatite coating of dental implants is controversial. The long-term fate of hydroxyapatite-coated implants has been the subject of some criticism. PURPOSE: The aim of this retrospective study was to assess the clinical outcome of hydroxyapatite-coated cylindrical root-form endosseous Impladent dental implants (LASAK Ltd, Prague, Czech Republic) during a six-year course. METHODS: Three-hundred and ninety-one consecutively placed implants were used in 169 patients and followed for four to six years. Interval and cumulative success of implants and prostheses survival was tabulated. Marginal bone loss was measured RESULTS: Of the total number of implants, 98.5% achieved initial osseointegration. The cumulative success was 98.3% after one year, 97.0% after three years, 92.8% after five years and 90.4% after six years. The prostheses survival at the end of the study was 100% for fixed bridges totally supported by implants, 96.5% for fixed bridges with combined implant and tooth support, 94.2% for single crowns, 90.9% for mandibular overdentures and 81.3% for maxillary overdentures. Marginal bone loss averaged 2.4 +/- 0.8 mm at the end of five years. CONCLUSION: The success rate of the investigated hydroxyapatite-coated implants was comparable with the data presented in the literature and with the results of the similar implants without hydroxyapatite-coating. However, the marginal bone loss was of interest. Longer monitoring of the implants is necessary.

The use of oxidized regenerated cellulose (surgicel) in closing Schneiderian membrane tears during the sinus lift procedure.

During the sinus lift procedure, undesirable perforations of the Schneiderian membrane can occur in up to 58% of cases. Several methods for their closing exist. This article presents a method of covering the perforation with a strip of oxidized regenerated cellulose (Surgicel). One or two layers of material swell after being saturated with blood, turning into a gelatinous mass and forming a tight and mechanically resistant seal. This simple method has been successfully tested on 223 perforations of the Schneiderian membrane that occurred over a period of 58 months.

Polarized Cu K edge XANES spectra of CuO--theory and experiment.

Polarized Cu K edge x-ray absorption near-edge structure (XANES) spectra of CuO are analyzed. Partial spectral components reflecting both dipole and quadrupole transitions are resolved from the experiment. Theoretical spectra were obtained using the real-space multiple-scattering technique and by calculating the band structure via the pseudopotential method. We demonstrate that the pre-peak is of a quadrupole character and find its decomposition into individual d components. The self consistent pseudopotential calculation, free from any constraints on the form of the potential, improves the agreement between theory and experiment in those areas where real-space calculation, based on non-self-consistent muffin-tin potential, fails. Therefore we argue that the most significant contributions to the Cu K edge XANES come from one-electron processes.

Selective intraarterial chemotherapy of tumors in the lingual artery territory by a new approach.

Selective intraarterial neoadjuvant chemotherapy of carcinoma in the region of the lingual artery was performed in 23 patients (bilaterally in 4 patients). The superficial temporal artery (STA) was surgically exposed and a preshaped infusion catheter was inserted. The catheter tip was maneuvered through the STA into the lingual artery under fluoroscopic guidance. Two combinations of cytostatic agents were then continually infused through the catheter for 5-9 days. Treatment response was observed in 16 patients, 9 of whom showed a complete response. The combination of cisplatin and 5-fluorouracil was found most effective. The catheter became dislocated six times among 27 catheterizations and in each instance the position could be corrected. No major complications were encountered. We conclude that selective infusion technique is safer than previously reported semiselective infusions techniques.

Longterm catheterization of the lingual artery for intraarterial cytostatic therapy.

The authors present a technique of longterm lingual artery catheterization for intraarterial regional chemotherapy. The transtemporal approach enables safe introduction through the external carotid artery. Catheterization technique is presented in 16 patients with the diagnosis of carcinoma baseos oris and carcinoma linguae. Both the lingual arteries were infused in four patients with tumors spreading over the midline. The dislocation of the catheter was found seven times of twenty catheterizations. The following catheter repozition was always successful.