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31.
Today, the sinus floor elevation procedure is not only being used on a routine basis, but clinicians are reporting high success rates. The sinus floor graft has become an important option in the treatment of the edentulous posterior maxilla, where vertical bone height is less than ideal. A review of maxillary sinus floor elevation as an integral part of restoring the posterior maxillary is discussed. The related anatomy of the area and current osteotomy techniques are reviewed. This article describes a trephine osteotomy, which is an alternative technique to the existing lateral antrostomy approach currently being used.  相似文献   
32.
The number of publications reporting on the survival of ART sealants and ART restorations has increased considerably in recent years. A systematic investigation of their longevity is therefore warranted. Based on three exclusion criteria, a literature search in the electronic libraries Pubmed and Medline revealed 28 eligible publications for inclusion in a meta-analysis. High mean survival rates for single-surface ART restorations using high-viscosity glass-ionomer in primary dentitions over 3 years were found (95% after 1 year to 86% after 3 years). These rates were statistically significantly higher than for those of multiple-surface ART restorations in primary dentitions (p<0.0001). High mean survival rates for single-surface ART restorations using high-viscosity glass-ionomer in permanent dentitions over 6 years were found (97% after 1 year to 72% after 6 years). The mean annual failure rates for single-surface ART restorations using high-viscosity glass-ionomer in primary and permanent dentitions and for multiple-surface ART restorations in primary dentitions are 4.7%, 4.7% and 17%, respectively. The number of studies reporting on the retention and caries preventive effect of ART sealants was low. It is concluded that single-surface ART restorations using high-viscosity glass-ionomer in both primary and permanent dentitions show high survival rates. Medium-viscosity glass-ionomer should not be used for ART restorations.  相似文献   
33.
BACKGROUND: Osteoma is a benign often asymptomatic neoplasm, consisting of well-differentiated mature bone. This paper reports a case of peripheral osteoma located in the anterior mandibular region and provides a review of the literature about this lesion in the jaws. PATIENT AND METHODS: A 43-year-old white woman presented with a swelling in the left mandible of 7 years duration. The English literature was reviewed over the past 76 years and data about location, histopathology and number of the peripheral osteomas, sex, and age of the patients were evaluated. RESULTS: Data analysis showed 69 well-documented cases of peripheral osteoma. Peripheral osteomas are more frequent in the mandible than the maxilla and the cancellous type was most frequent; males and females are equally affected in the mandible; the age range was 9-85 years. CONCLUSION: The peripheral type of osteoma is most common in the lower jaws, occurs at the surface of the cortical bone and is sessile or pedicled.  相似文献   
34.
Microwave energy has been used as an alternative method for disinfection and sterilization of dental prostheses. This study evaluated the influence of microwave treatment on dimensional accuracy along the posterior palatal border of maxillary acrylic resin denture bases processed by water-bath curing. Thirty maxillary acrylic bases (3-mm-thick) were made on cast models with Clássico acrylic resin using routine technique. After polymerization and cooling, the sets were deflasked and the bases were stored in water for 30 days. Thereafter, the specimens were assigned to 3 groups (n=10), as follows: group I (control) was not submitted to any disinfection cycle; group II was submitted to microwave disinfection for 3 min at 500 W; and in group III microwaving was done for 10 min at 604 W. The acrylic bases were fixed on their respective casts with instant adhesive (Super Bonder) and the base/cast sets were sectioned transversally in the posterior palatal zone. The existence of gaps between the casts and acrylic bases was assessed using a profile projector at 5 points. No statistically significant differences were observed between the control group and group II. However, group III differed statistically from the others (p<0.05). Treatment in microwave oven at 604 W for 10 min produced the greatest discrepancies in the adaptation of maxillary acrylic resin denture bases to the stone casts.  相似文献   
35.
A 6-year-old girl with Glanzmann thrombasthenia presented with caries and periapical lesions in the primary mandibular second molars and moderate gingivitis of the maxillary and mandibular anterior teeth. Dental extraction was recommended, and before every surgical intervention, the patient underwent platelet-concentrate transfusion to prevent hemorrhage. Epsilon aminocaproic acid was administered 6 hours before, and 48 hours after every dental procedure to prevent bleeding. In this case, treatment was effective in the prevention of hemorrhagic complications, during the required dental procedures.  相似文献   
36.

Objective:

to analyze the pattern of disocclusion during excursive mandibular movements and presence or absence of occlusal interferences and occlusal pathologies (gingival recession and abfraction).

Method:

examination of 120 individuals divided into two groups, as follows: Group 1-90 patients with complete cleft lip and palate (study group), subdivided into 30 patients with complete left unilateral cleft lip and palate, 30 patients with complete right unilateral cleft lip and palate and 30 patients with complete bilateral cleft lip and palate; Group 2-30 individuals without clefts (control group).

Results:

58.8% of patients in Group 1 presented unilateral or bilateral canine guidance, 26.6% presented unilateral or bilateral group function and 54.4% presented lateral movements through the posterior teeth. Regarding protrusive movements, 80% presented anterior guidance and 20% presented posterior guidance. In Group 2, 69.6% of individuals presented unilateral or bilateral canine guidance, 43.2% presented unilateral or bilateral group function and only 13.3% presented lateral movements through the posterior teeth; 3.4% presented protrusion through the posterior teeth.

Conclusions:

there was no difference in the pattern of disocclusion between subgroups of patients with clefts. Group 2 presented predominance of bilateral group function, whereas Group 1 presented a higher prevalence of posterior guidance during lateral movements. Protrusion occurred primarily through anterior guidance in Group 2 and through the posterior teeth in Group 1. There was high prevalence of occlusal interferences at the molar area for both groups, yet with no correlation with occlusal pathologies (recession and abfraction).  相似文献   
37.

Introduction

The aim of this study was to evaluate the rat alveolar bone response after the implantation of experimental light-cured mineral trioxide aggregate (MTA) or Angelus MTA (Angelus, Londrina, Paraná, Brazil) by histological and fluorescence analysis.

Methods

Thirty Wistar Albino rats were divided into three groups. In the control group, empty polyethylene tubes were inserted into the rat alveolar sockets immediately after extraction. In the other groups, the tubes were filled with light-cured MTA or Angelus MTA. Five animals from each group were injected with calcein on day 7, alizarin on day 14, and oxytetracycline on day 21. On day 30, these animals were killed, and the right hemimaxillas were removed and histologically processed. Half of the maxillas were processed and stained with hematoxylin and eosin. The remaining maxillas were processed for fluorescence analysis and stained with Stevenel blue and alizarin red. New bone was histomorphometrically evaluated using a Merz grid.

Results

The light-cured MTA presented a similar response when compared with Angelus MTA; it was characterized by a mild inflammatory response and complete bone healing. In the light-cured MTA group, the fluorescence areas were more evident at 21 days, showing an increase in bone formation. However, dystrophic mineralization was observed only with Angelus MTA.

Conclusions

It was concluded that both materials present a similar inflammatory response and bone healing, but dystrophic mineralization was observed only with Angelus MTA.  相似文献   
38.
39.
Selective blockade of nociceptive neurons can be achieved by the delivery of permanently charged sodium channel blockers through the pores of nociceptive ion channels. To assess the feasibility of this application in the dental area, we investigated the electrophysiological and neurochemical characteristics of nociceptive dental primary afferent (DPA) neurons. DPA neurons were identified within trigeminal ganglia labeling with a retrograde fluorescent dye applied to the upper molars of adult rats. Electrophysiological studies revealed that the majority of dental primary afferent neurons showed characteristics of nociceptive neurons, such as sensitivity to capsaicin and the presence of a hump in action potential. Immunohistochemical analysis revealed a large proportion of DPA neurons to be IB(4)-positive and to express TRPV1 and P2X(3). Single-cell RT-PCR revealed mRNA expression of various nociceptive channels, including the temperature-sensitive TRPV1, TRPA1, TRPM8 channels, the extracellular ATP receptor channels P2X(2) and P2X(3), as well as the nociceptor-specific sodium channel, Na(V)1.8. In conclusion, DPA neurons have the electrophysiological characteristics of nociceptors and express several nociceptor-specific ion channels. Analysis of these data may assist in the search for a new route of entry for the delivery of membrane-impermeant local anesthetics.  相似文献   
40.
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