The effectiveness of 2-implant overdentures - a pragmatic international multicentre study.

The purpose of this multicentre observational study was to determine patient satisfaction with either conventional dentures or mandibular 2-implant overdentures in a 'real world' setting. Two hundred and three edentulous patients (mean age 68·8 ± 10·4 years) were recruited at eight centres located in North America, South America and Europe. The patients were provided with new mandibular conventional dentures or implant overdentures supported by two implants and ball attachments. At baseline and at 6 months post-treatment, they rated their satisfaction with their mandibular prostheses on 100-mm visual analogue scale questionnaires. One hundred and two (50·2%) participants had valid baseline and 6-month satisfaction data. Although both groups reported improvements, the implant overdenture group reported significantly higher ratings of overall satisfaction, comfort, stability, ability to speak and ability to chew. These results suggest that edentulous patients who choose mandibular implant overdentures have significantly greater improvements in satisfaction, despite their relatively higher cost, than those who choose new conventional dentures.

[Prosthetic dilemmas. Immediate versus conventional loading of implants in the edentulous mandible]. / Prothetische dilemma's. Vroeg of laat belasten van implantaten in de edentate onderkaak.

Most edentulous patients experience retention problems with their lower denture, which often results in functional problems and also social ones. Since the introduction of the osseointegration concept for the edentulous patient, this patient group has been successfully treated, with demonstrably positive effects for long periods of time. The traditional protocol calls for late loading of the implants. Immediate loading of 4 implants with a bar-retained overdenture or a fixed dental prosthesis has proved to be as successful as the delayed (non-immediate) loading concept. The treatment of the edentulous patient with an overdenture on two implants has until recently been based on a treatment protocol which called for early, but not immediate, yet not definitive retention form. However, recent research shows that immediate loading of 2 implants with an overdenture is just as successful and what's more not more expensive. Because of newly developed treatment concepts delayed loading no longer has to be an automatic choice.

An eight-year follow-up to a randomized clinical trial of aftercare and cost-analysis with three types of mandibular implant-retained overdentures.

Mandibular implant overdentures increase satisfaction and the quality of life of edentulous individuals. Long-term aftercare and costs may depend on the type of overdentures. One hundred and ten individuals received one of 3 types of implant-retained overdentures, randomly assigned, and were evaluated with respect to aftercare and costs. The follow-up time was 8 years, with only seven drop-outs. No significant differences (Kruskal-Wallis test) were observed for direct costs of aftercare (p = 0.94). The initial costs constituted 75% of the total costs and were significantly higher in the group with a bar on 4 implants, compared with the group with a bar on 2 implants and the group with ball attachments on 2 implants (p = 0.018). The last group needed a significantly higher number of prosthodontist-patient aftercare contacts, mostly for re-adjustment of the retentive system. It can be concluded that an overdenture with a bar on 2 implants might be the most efficient in the long term.

An eight-year follow-up to a randomized clinical trial of participant satisfaction with three types of mandibular implant-retained overdentures.

Studies have shown that mandibular implant overdentures significantly increase satisfaction and quality of life of edentulous elders. Improved chewing ability appears to have a positive impact on nutritional state. Therefore, it is important to determine the best design of this prosthesis over the long term. In this randomized controlled trial, three groups of edentulous participants with atrophic mandibles wore 3 types of implant overdentures. During an eight-year follow-up, only seven of the 110 participants had dropped out of this study. Almost all participants were still satisfied with their overdentures. Participant satisfaction concerning retention and stability of the mandibular overdenture had decreased significantly in the two-implant ball attachment group, whereas the opinion of participants in the single- and triple-bar groups was still at the same level. The long-term results suggest that a mandibular overdenture retained by 2 implants with a single bar may be the best treatment strategy for edentulous people with atrophic ridges.

A high degree of genetic diversity is revealed in Isatis spp. (dyer's woad) by amplified fragment length polymorphism (AFLP).

Genetic diversity in 38 genotypes, representing 28 individual genotypes from five landraces of Isatis tinctoria (three German: Tubingen, Potsdam and Erfurt, one Swiss and one English), five genotypes of Isatis indigotica (Chinese woad) and five genotypes of Isatis glauca, were investigated using AFLP analysis. Five primer combinations detected a total of 502 fragments of which 436 (86.9%) were polymorphic. The level of polymorphism recorded within each species was 29.8, 86.9 and 35.8% for I. indigotica, I. tinctoria and I. glauca, respectively. Clearly, genetic diversity within I. tinctoria was greater than that observed in I. indigotica or I. glauca. Cluster analyses of the AFLP data using UPGMA and PCO revealed the complete separation of the genotypes of each species into distinct groups. I. indigotica separated as an entirely independent group, whereas I. glauca formed a separate cluster within the I. tinctoria group. Indeed, I. tinctoria and I. glauca are more closely related to each other than either is to I. indigotica. In addition, the genotypes of each landrace, apart from one from the English group, were clearly discriminated. However, the anomalous genotype did associate with the rest of its group when it was linked with the Erfurt group. These results provide new and useful information about the make-up of the Isatis genome, which has not previously been evaluated. They will be useful in the selection of plant material for variety development and conservation of the gene-pool.

Cutaneous segmental neurofibromatosis.

Two patients with multiple cutaneous neurofibromas restricted to a dermatomal portion of the skin are described. Neither patient had clinical evidence or a family history of generalized neurofibromatosis. Whether this represents a distinct disorder, sui generis, or a variant in the spectrum of neurofibromatosis is unknown.