Removed Case of HA-coated Implant Which Showed Deposition of Calculus-like Mass. Observation on It's Surface by SEM, EPMA and WDX.

Accession number;01A1027775
Title;Removed Case of HA-coated Implant Which Showed Deposition of Calculus-like Mass. Observation on It's Surface by SEM, EPMA and WDX.
Author; TSUTSUMI KOJI (Kitanihonkokuimpurantokenkyukai) NAGAYAMA MASATO (Kitanihonkokuimpurantokenkyukai) TOMITA TATSUHIRO (Kitanihonkokuimpurantokenkyukai) MISHIMA AKIRA (Kitanihonkokuimpurantokenkyukai) KAKU TOORU (Hokkaidoiryodai Shi Kokubyorigaku)
Journal Title;Nippon Koku Inpuranto Gakkaishi
Journal Code:G0262C
ISSN:0914-6695
VOL.14;NO.3;PAGE.461-469(2001)
Figure&Table&Reference;FIG.10, REF.41
Pub. Country;Japan
Language;Japanese
Abstract;Hydroxyapatite (HA)-coated implants have been a subject of great interest since the mid-1980s. Various clinical studies have shown that HA-coatings lead to good clinical results over a 15-year period. Statistics with a success rate of 95% were reported over a 5-year period. More recently, however, an increased number of failures with HA-coated implants have been reported. One case of an HA-coated implant, which had to be removed due to implant mobility, marginal swelling and redness, and marginal bone loss (funnel-shaped resorption) around the implant, at 4 years after the implant had been placed, in a 48-year-old male patient, was reported. An explanted HA-coated titanium cylinder-form implant was examined, using scanning electron microscopy (SEM) and an electron probe X-ray microanalyzer (EPMA) to analize the main constructive elements. Also, soft tissue removed from the implant socket was microscopically examined. The results were as follows: 1. The removed implant demonstrated, macroscopically and microscopically, a dental calculus-like deposit on the plasma-sprayed surface, and loss of the HA-coating, with the presence of a smooth titanium substrate. 2. The loss of HA-coating was seen within the hole of the apical end of the implant. 3. For the EPMA data, the implant material mainly consisted of titanium, with a loss of the HA-coated layer. The dental calculus-like deposit chiefly consisted of calcium and phosphate, and showed no bone structure. 4. Microscopic examination revealed that granulation tissue replaced the resorbed bone and was separated from the implant itself by proliferating squamous epithelium. Epithelium proliferated apically to the encapsulated granulation tissue. The granulation tissue that resulted from the inflammatory process began marginally and followed the bacterial movement; the process proceeded rapidly with the loss of an implant.... (author abst.)