influence of inclined implants and attachments on the retention and longevity of implant-retained overdentures: an in vitro study

Statement of Problem: Several dilemmas have been reported with regard to the retention and longevity of implant-retained overdentures. A few studies have investigated the influence of implant and attachment inclination on the path of insertion and withdrawal of the prosthesis and on the retention and longevity of the overdenture. However, no study has been reported with regard to the influence of labio-lingual inclination on the aforementioned indices

Purpose: The purpose of this study was to investigate the influence of implants and attachments with 5 and 10 degrees of inclination on the retention and longevity of implant-retained overdentures

Materials and Method: In this experimental study, 10 implants and 50 attachments were selected and divided into five groups: Group I: two implants and attachments parallel to each other; Group II: implants inclined at an angle of 5 degrees and attachments without any inclination; Group III: implants and attachments inclined at an angle of 5 degrees; Group IV: implants inclined at an angle of 10 degrees and attachments without any inclination; Group V: implants and attachments inclined at an angle of 10 degrees. All the attachments and implants were lubricated by artificial saliva. Initial retention [N] of blocks was measured through the Universal Testing Machine [SANTAM, STM-20]. The blocks were removed and replaced for 3000 cycles and retention was measured after each 500 cycles. The retention was measured five times for each group and the registered data were analyzed by One-way ANOVA and T-test

Results: The maximum and minimum amounts of initial retention were 5.54 +/- 0.3 and 3.88 +/- 0.19 and were related to groups III and I, respectively. There was no significant difference among groups II, III, IV, and V with regard to the amount of retention of implants and attachments [p < 0.3]. However, there was a significant difference between the control group, group I, and the other groups [p <0.01]

Conclusion: Although the placement of labially inclined implants results in an increase in the initial retention, it will lead to a large decrease in the amount of retention after the last cycle. However, this amount of inclination [5 or 10 degrees] does not have any negative effect on the prosthesis longevity

Moyamoya induced acute paraplegia in a child with epilepsy

Moyamoya disease [MMD] is a chronic, occlusive, cerebrovascular disorder of unknown pathogenesis, characterized by progressive stenosis of the bilateral supraclinoid internal carotid arteries, with concomitant formation of tortuous arterial collateral vessels at the base of the brain, which reconstitute distal branches of the cerebral circulation. In Japanese, "Moyamoya" means "hazy puff of smoke" and refers to the angiographic appearance of the abnormal network of vessels that develop at the base of the brain and basal ganglia to supply of collateral route of blood flow. We report here the case of Moyamoya disease in a 5 year-old girl with normal mentality with a one year history of epilepsy, with Todd's paralysis. This condition is rare and most patients are diagnosed in childhood. With this report we aim to underscore the possibility that usual neurological sign could be associated with unusual neurological disorders

evaluation of occlusal contacts of remounted complete denture before final occlusal adjustment

There are various studies about the advantages and effect of remounting procedures on success of complete dentures; however, the number and distribution of occlusal contacts of remounted complete dentures before occlusal adjustment have not been sufficiently assessed. The purpose of this study was to evaluate the distribution and number of occlusal contacts of remounted complete dentures in centric relation before occlusal adjustment. In this cross-sectional study, 207 newly constructed complete dentures were remounted on a modified two dimensional articulators. For identification of occlusal contacts, a 60 micron articulating paper was used to mark the actual contacts of the opposing teeth. The articulating paper was interposed between the teeth, and contacts were obtained by holding the articulating paper between the opposing teeth. The number and distribution of the occlusal contacts on each complete denture in centric relation were recorded and analyzed, using descriptive statistics. Out of the 207 studied complete dentures, 203 had occlusal contacts. Among 203 complete dentures, 138 [68%] and 65 [32%] had bilateral and unilateral occlusal contacts, respectively. The total number of occlusal contacts was 713 with a range of 1-14. The mean number of occlusal contacts was 3.44 +/- 2.29. The results suggest that the number of occlusal contacts of remounted complete dentures before occlusal adjustments by articulating paper was low, the posterior teeth did not meet evenly all around the arch at the first contact, and delivery of such complete dentures may lead to occlusal error and unstable complete denture