Evaluation of the three-year experience with all-ceramic crowns with polycrystalline ceramic cores.

The objective of the study was to evaluate the clinical outcomes of all-ceramic crowns three years after placement of the restoration in the oral cavity. The aim of the present clinical study were surveyed the Procera®, Cercon® and LAVA™ systems. In total, 121 crowns were followed in 33 patients (7 men and 26 women) with an average age of 53.5 years. The eighty crowns were placed in anterior and forty one crowns in posterior teeth. The crowns were fabricated in two dental laboratories and delivered in two private dental practices. The clinical trial was conducted according to American Dental Association guidelines. The patients were requested to provide their consent to the regular clinical examination including radiographic and photographic records. A total of 102 crowns were made of zirconium oxide ceramic cores - 58 Cercon®; 43 LAVA™, while 19 crowns were made of aluminum oxide cores Procera®. The veneering ceramic LAVA™ Ceram was used. The success rate was analyzed using Kaplan-Meier statistics and, in our case, the overall three-year success rate reached 96.7%. All-ceramic crowns with polycrystalline ceramic cores have low susceptibility to fracture, in this study just 3.3%.

Giant cell reparative granuloma in the mandible--case report and review of the literature.

OBJECTIVE: Central giant cell granuloma (GCG) is defined as an intraosseous lesion consisting of cellular fibrous tissue containing multiple foci of hemorrhage, aggregations of multinucleated giant cells. Peripheral GCG is a reactive exophytic lesion occurring on the gingiva and alveolar ridge originating from the periosteum or periodontal membrane, usually as a result of local irritating factors. STUDY DESIGN: The case report evaluated long-term therapy of giant cell granuloma. A 9-year-old boy generally healthy was admitted to our clinic with a swelling in the frontal area of mandible. Giant cell granuloma was detected. Surgical curettage was applied. After 3 years of the operation, the recurrence was seen during the physical examination. The new GCG was removed. The prosthetic rehabilitation including implants insertion (18-year-old adult patient) finished treatment. RESULTS: Three-year recall confirmed the stability of treatment. CONCLUSION: Esthetical and functional therapy is of great importance in the patient's rehabilitation.

Denture reconstruction of the edentulous upper jaw in cleft palate using implants--clinical report.

OBJECTIVE: Early prosthodontic therapy (usually at around 18 years of age) often leads to early loss of teeth and in extreme cases to complete loss of dentition at between 40 and 50 years of age. PATIENTS: This report describes the clinical features of two middle-aged cleft patients. Edentulous maxilla with cleft defect was treated with 6 implants supported by fixed appliance. RESULTS: Treatment of the whole dental arch on the basis of implants is currently frequently used as it provides a possibility of thorough functional and aesthetic therapy to a patient. The biomechanics of the reconstruction enables individual adjustment of the shape of the dental arch. CONCLUSIONS: The problem in cleft patients involves other diameter relations in the dental arch caused by the defect alone or also by affecting the growth of the maxillary segment by surgery. A potentially removable framework is therefore the main method of choice because the position of the implants must be prosthetically modified.

Shape and size of dental arch--a five-year prospective study.

OBJECTIVES: The diagnostic procedure commences with the initial examination, during which a number of individual findings of the occlusion or malocclusion are clarified [1]. The objective is to describe the morphological and functional characteristics on each patient using specific guidelines, and then to provide a prognosis of the therapy. Upper and lower arch compression in first premolars and molars area was visible before treatment. METHODS: A special device (Czech technical university research prototype) was prepared for this purpose. The optical head contains a digital color camera. The front of the optical head consists of a removable prism which is put into the mouth. The findings can display live images from the camera, which can be archived on a PC. The device captured and geometrically calibrated images permitting comparison of several different dental casts. RESULTS: In the first part of this study 792 sets of study plaster casts were screened. Measurements of dental arch width between reference points of canines, first premolars and first molars were made: upper jaw: men: 3-3-35.1 mm (SE 0.13); 4-4-37.5 mm (SE 0.13); 6-6-48.1 mm (SE 0.19); women: 3-3-33.4 mm (SE 0.13); 4-4-35.6 mm (SE 0.15); 6-6-46.7 mm (SE 0.19). The second part concerns the group of 36 patients which is different from the 792 controls. There were studied changes between initial, post-treatment and post-retention alignment of upper and lower dental arch. CONCLUSIONS: Geometrically calibrated images help compare several different steps of the treatment and show a significant difference between patients before and after treatment.

A two-year clinical study of metal-ceramic and metal-polymer crowns.

The purpose of this study was to compare full metal crowns with two different types of veneering material - ceramics and polymer after a two-year period in a function. The aim was to evaluate the changes of occlusal relief, marginal adaptation, break of material, changes of shape and color and gingival status. One hundred and two crowns were examined in 34 patients immediately after cementation, and they were reviewed within two years of crown placement. These fixed restorations were checked according two modified US Public Health Service System criteria. After two years the crowns were found clinically intact in 94% for metal-ceramics versus 98% for metal-polymer. No crown was lost. There were found significant differences in positions of a crown margin between both materials and marginal adaptation between initial (baseline) and follow-up results. Gingival health at baseline was related in optimal in 67% versus 77%, after two years in 43% versus 71%. Slight mismatch in color occurred in 0 versus 60% crowns, obvious mismatch was apparent in 0 versus 21% crowns after two years. Within the limitations of this study, it was found that the examined metal crowns with two different veneerings are very stable fixed restorations, mechanical resistance and integrity of polymer material was surprisingly good but its color stability presented mismatch after two-years period. Ceramic veneering was excellent in color match but there were three visible cracks of the ceramic layer.

[Synthesis and antibacterial activity of thiosemicarbazones of 3-acylquinolones]. / Syntéza a antibakteriální aktivita thiosemikarbazonu nekterých 3-acylchinolonu.

Oxidation of 3-acetyl derivatives of 3-acetyl-1-ethyl-1,4-dihydro-6,7-methylenedioxyquinoline-4-one (VIc) and 3-acetyl-7-chloro-1-ethyl-6-fluoro-1,4-dihydroquinoline-4-one (VId) with selenium dioxide provided the corresponding acids, [1-ethyl-1,4-dihydro-6,7-methylenedioxy-4-oxoquinoline-3-yl]glyoxylic acid (VIe) and [7-chloro-1-ethyl-6-fluoro-1,4-dihydro-4-oxoquinoline-3-yl]glyoxylic acid (VIf), respectively. Reactions of compounds VIc--VIf with thiosemicarbazide yielded the respective thiosemicarbazones of 3-acetyl-1-ethyl-1,4-dihydro-6,7-methylenedioxyquinoline-4-one (VIIa), 3-acetyl-7-chloro-1-ethyl-6-fluoro-1,4-dihydroquinoline-4-one (VIIb), [1-ethyl-1,4-dihydro-6,7-methylenedioxy-4-oxoquinoline-3-yl]glyoxylic acids (VIId). The compounds showed no significant in vitro antibacterial activity.

[Rehabilitation of the dentition using intraosseous blade implants]. / Príspevek k rehabilitaci chrupu pomocí nitrokostních cepelkovych implantátu.

Intraosseous blade vent implants extend hitherto existing clinical methods of prosthetic treatment of some conditions of defective teeth by new possibilities. It is a method which can produce satisfactory and long-term results. One of the prerequisites is, however, that generally valid and local limitations for indication of the implantation will be respected, that the implantation will be implemented by reliable surgical technique along with high standard prosthetic treatment which in the course of recovery will carry the implant to its functional period. Results of our investigations revealed unequivocally that the use of implants with a low or predominantly low intraosseous part leads in the majority to unsatisfactory results of implantations.