New bone formation and trabecular bone microarchitecture of highly porous tantalum compared to titanium implant threads: A pilot canine study

作者：Lee Jin Whan; Wen Hai Bo; Gubbi Prabhu; Romanos Georgios E

来源：Clinical Oral Implants Research, 2018, 29(2): 164-174.

DOI：10.1111/clr.13074

<jats:title>Abstract</jats:title><jats:sec><jats:title>Aim</jats:title><jats:p>This study evaluated new bone formation activities and trabecular bone microarchitecture within the highly porous region of Trabecular Metal™ Dental Implants (<jats:styled-content style="fixed-case">TM</jats:styled-content>) and between the threads of Tapered Screw‐Vent® Dental Implants (<jats:styled-content style="fixed-case">TSV</jats:styled-content>) in fresh canine extraction sockets.</jats:p></jats:sec><jats:sec><jats:title>Materials and methods</jats:title><jats:p>Eight partially edentulated dogs received four implants (4.1 mmD × 13 mmL) bilaterally in mandibular fresh extraction sockets (32 <jats:styled-content style="fixed-case">TM</jats:styled-content>, 32 <jats:styled-content style="fixed-case">TSV</jats:styled-content> implants), and allowed to heal for 2, 4, 8, and 12 weeks. Calcein was administered to label mineralizing bone at 11 and 4 days before euthanasia for dogs undergoing all four healing periods. Biopsies taken at each time interval were examined histologically. Histomorphometric assay was conducted for 64 unstained and 64 stained slides at the region of interest (<jats:styled-content style="fixed-case">ROI</jats:styled-content>) (6 mm long × 0.35 mm deep) in the midsections of the implants. Topographical and chemical analyses were also performed.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>Histomorphometry revealed significantly more new bone in the <jats:styled-content style="fixed-case">TM</jats:styled-content> than in the <jats:styled-content style="fixed-case">TSV</jats:styled-content> implants at each healing time (<jats:italic>p</jats:italic> = .0014, .0084, .0218, and .0251). Calcein‐labeled data showed more newly mineralized bone in the <jats:styled-content style="fixed-case">TM</jats:styled-content> group than in the <jats:styled-content style="fixed-case">TSV</jats:styled-content> group at 2, 8, and 12 weeks (<jats:italic>p</jats:italic> = .045, .028, .002, respectively) but not at 4 weeks (<jats:italic>p</jats:italic> = .081). Histologically <jats:styled-content style="fixed-case">TM</jats:styled-content> implants exhibited more bone growth and dominant new immature woven bone at an earlier time point than <jats:styled-content style="fixed-case">TSV</jats:styled-content> implants. The parameters representing trabecular bone microarchitecture corroborated faster new bone formation in the <jats:styled-content style="fixed-case">TM</jats:styled-content> implants when compared to the <jats:styled-content style="fixed-case">TSV</jats:styled-content> implants. <jats:styled-content style="fixed-case">TM</jats:styled-content> exhibited an irregular faceted topography compared to a relatively uniform microtextured surface for <jats:styled-content style="fixed-case">TSV</jats:styled-content>. Chemical analysis showed peaks associated with each implant's composition material, and <jats:styled-content style="fixed-case">TSV</jats:styled-content> also showed peaks reflecting the elements of the calcium phosphate blasting media.</jats:p></jats:sec><jats:sec><jats:title>Conclusions and clinical implications</jats:title><jats:p>Results suggest that the healing pathway associated with the highly porous midsection of <jats:styled-content style="fixed-case">TM</jats:styled-content> dental implant could enable faster and stronger secondary implant stability than conventional osseointegration alone; however, prospective clinical studies are needed to confirm these potential benefits in patients with low bone density, compromised healing, or prior implant failure.</jats:p></jats:sec>

• 出版日期2018-2