In this thesis, four experimental studies are reported. Two concern the surface structure of commercially relevant dental implant materials. Characterisation of four treated substrates supplied by Straumann AG was carried out. These include substrates equivalent to the commercially available SLA, SLActive and Roxolid implants. The materials vary in substrate alloy, commercially pure (grade 2) Ti and a TiZr alloy, and surface preparation treatments. All substrates are sandblasted and acid etched however post-etching one set are stored in air whilst the others are stored in saline. Within the work both substrate composition and surface treatment is shown to impact on the respective surface oxide thickness, crystallinity and morphology. The other two experimental studies concern calcium phosphate deposition from solution onto substrates. The first investigation is the deposition of calcium phosphate from a simulated body fluid onto implant-like substrates, shown to be structurally equivalent to the SLA and SLActive implant surfaces. The effect of surface modifications on calcium phosphate deposition is investigated; over the period investigated calcium phosphate did not deposit onto the SLA substrate, whilst deposition occurred within 3 days on the SLActive substrate. The role of Mg2+ ions in the simulated body fluid is also investigated, with increased [Mg2+] resulting in a longer induction period and modified crystallinity of the hydroxyapatite film formed. The final study is a model study of the initial calcium phosphate deposition on to substrates. TiO2 rutile (110) and Al2O3 corundum (0001) were prepared to be atomically flat and then exposed to a simple calcium phosphate solution. Changes in surface structure and surface chemistry over the first three hours of exposure were investigated. Deposition occurred rapidly on both substrates with a complete surface coverage after 3 hours.

Made available in DSpace on 2014-06-11T19:28:03Z (GMT). No. of bitstreams: 0 Previous issue date: 2000-04-17Bitstream added on 2014-06-13T20:17:45Z : No. of bitstreams: 1 shibli_ja_me_arafo.pdf: 739694 bytes, checksum: 57c9b17fc168fc0329fc6f5001a03672 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A microbiota presente na peri-implantite induzida por ligadura, em diferentes superfícies de implantes osseointegrados, foi analisada em 6 cães adultos machos. 36 implantes osseointegrados (9 Ticp: titânio comercialmente puro; 9 TPS: titânio plasma spray; 9 HA: hidroxiapatita; 9 superfícies tratadas com ácidos) foram inseridos e distribuídos igualmente 3 meses após exodontia de todos os pré-molares inferiores. Após um período de 3 meses de osseointegração, os implantes receberam os cicatrizadores. Decorridos 45 dias de cicatrização, amostras peri-implantares foram colhida, utilizando pontas de papel, no período 0 e após a colocação de ligaduras com fio de algodão, nos períodos 20, 40 e 60 dias. A contagem total de microrganismos (CTM) e a proporação de A. actinomycetemcomitans, Bacteroides forsythus, P. gingivalis, P. intermedia, Campylobacter sp, Capnocytophaga sp., Fusobacterium sp., Peptostreptococcus micros, bastonetes anaeróbios Gram-negativos, Streptococcus beta-hemolíticos, Eikenella corrodens e Candida sp. foram analisadas. Não houve diferença da CTM entre as diferentes superfícies (p>0,05). A Pg não foi detectada no tempo 0; nos tempos 20 e 40 foi detectada em 12 implantes (4 Ticp, 4 HA, 2 TPS e 1 Sup. Trat. com ácidos) e no período 60 dias, em 9 (2 Ticp, 3 HA, 2 TPS e 1 Sup. Trat. com ácidos), tendo menor afinidade à superfície tratada com ácidos. Pi foi detectada em 5 implantes (2 Ticp, 2 HA e 1 Sup. Trat. com ácidos) no período 0 e em 100% dos implantes nos demais períodos. Fusobacterium sp. foi detectado em todos os períodos, tendo uma maior afinidade à HA. Streptococcus beta-hemolíticos foi detectado em 6 implantes (3 Ticp, 1 TPS e 2 HA) no período 0 e 30, 26 e 24 implantes respectivamente nos períodos 20, 40 e 60. Campylobacter sp. e Candida sp. foram detectadas em baixas proporções. Os demais microrganismos não... . / The microbiota associated with ligature-induced peri-implantitis, in different dental implants surfaces, was investigated by cultivation on enriched non-selective and various selective solid media, in 6 mongrel dogs. 36 dental implants (9 Ticp: titanium commercially pure; 9 TPS: titanium plasma spray; 9 HA: hidroxiapatite; 9 surfaces acid-etched) were placed in a similar distribution in all dogs 3 months after extraction of all premolars in mandible. Following a healing period of 3 months, healing abutments were installed and 45 days after cotton ligatures were placed and oral-cleaning procedures abolished for 2 months to induce vertical bone loss of about 40%. Microbial samples were with paper points on day of ligature placement and after 20, 40 and 60 days. The total number of cultivable bacteria and proportions of A. actinomycetemcomitans, Bacteroides forsythus, P. gingivalis, P. intermediate, Campylobacter sp., Capnocytophaga sp., Fusobacterium sp., Peptostreptococcus micros, Enteric Gram-negative rods, beta-hemolytic Streptococcus, Eikenella corrodens and Candida sp. were analyzed. No significant microbiological differences were observed among the different surfaces (p>0,05). Pg was not detected in the time 0; already in the times 20 and 40 were detected in 12 dental implants (4 Ticp, 4 HA, 2 TPS and 1 acid-etched surface) and in the period 60 days, in 9(2 Ticp, 3 HA, 2 TPS and 1 acid-etched surface), tends smaller affinity to eh surface with acids-etched surface. Pi was detected in 5 implants (2 Ticp, 2 HA and 1 acid-etched surface) in the period 0 and in 100% of implants in other periods. Fusobacterium sp. was detected in all the periods, tends a larger affinity to HA. Beta-hemolytic Streptococcus was detected in 6 implants (3 Ticp, 1 TPS and 2 HA) in the period 0 and 30, 26 and 24... (Complete abstract, click electronic address below).

Orientador: Elcio Marcantonio Junior / Banca: Izabel Yoko Ito / Banca: Roberto Fraga Moreira Lotufo / Resumo: A microbiota presente na peri-implantite induzida por ligadura, em diferentes superfícies de implantes osseointegrados, foi analisada em 6 cães adultos machos. 36 implantes osseointegrados (9 Ticp: titânio comercialmente puro; 9 TPS: titânio plasma spray; 9 HA: hidroxiapatita; 9 superfícies tratadas com ácidos) foram inseridos e distribuídos igualmente 3 meses após exodontia de todos os pré-molares inferiores. Após um período de 3 meses de osseointegração, os implantes receberam os cicatrizadores. Decorridos 45 dias de cicatrização, amostras peri-implantares foram colhida, utilizando pontas de papel, no período 0 e após a colocação de ligaduras com fio de algodão, nos períodos 20, 40 e 60 dias. A contagem total de microrganismos (CTM) e a proporação de A. actinomycetemcomitans, Bacteroides forsythus, P. gingivalis, P. intermedia, Campylobacter sp, Capnocytophaga sp., Fusobacterium sp., Peptostreptococcus micros, bastonetes anaeróbios Gram-negativos, Streptococcus beta-hemolíticos, Eikenella corrodens e Candida sp. foram analisadas. Não houve diferença da CTM entre as diferentes superfícies (p>0,05). A Pg não foi detectada no tempo 0; nos tempos 20 e 40 foi detectada em 12 implantes (4 Ticp, 4 HA, 2 TPS e 1 Sup. Trat. com ácidos) e no período 60 dias, em 9 (2 Ticp, 3 HA, 2 TPS e 1 Sup. Trat. com ácidos), tendo menor afinidade à superfície tratada com ácidos. Pi foi detectada em 5 implantes (2 Ticp, 2 HA e 1 Sup. Trat. com ácidos) no período 0 e em 100% dos implantes nos demais períodos. Fusobacterium sp. foi detectado em todos os períodos, tendo uma maior afinidade à HA. Streptococcus beta-hemolíticos foi detectado em 6 implantes (3 Ticp, 1 TPS e 2 HA) no período 0 e 30, 26 e 24 implantes respectivamente nos períodos 20, 40 e 60. Campylobacter sp. e Candida sp. foram detectadas em baixas proporções. Os demais microrganismos não... (Resumo completo, clicar acesso eletrônico abaixo). / Abstract: The microbiota associated with ligature-induced peri-implantitis, in different dental implants surfaces, was investigated by cultivation on enriched non-selective and various selective solid media, in 6 mongrel dogs. 36 dental implants (9 Ticp: titanium commercially pure; 9 TPS: titanium plasma spray; 9 HA: hidroxiapatite; 9 surfaces acid-etched) were placed in a similar distribution in all dogs 3 months after extraction of all premolars in mandible. Following a healing period of 3 months, healing abutments were installed and 45 days after cotton ligatures were placed and oral-cleaning procedures abolished for 2 months to induce vertical bone loss of about 40%. Microbial samples were with paper points on day of ligature placement and after 20, 40 and 60 days. The total number of cultivable bacteria and proportions of A. actinomycetemcomitans, Bacteroides forsythus, P. gingivalis, P. intermediate, Campylobacter sp., Capnocytophaga sp., Fusobacterium sp., Peptostreptococcus micros, Enteric Gram-negative rods, beta-hemolytic Streptococcus, Eikenella corrodens and Candida sp. were analyzed. No significant microbiological differences were observed among the different surfaces (p>0,05). Pg was not detected in the time 0; already in the times 20 and 40 were detected in 12 dental implants (4 Ticp, 4 HA, 2 TPS and 1 acid-etched surface) and in the period 60 days, in 9(2 Ticp, 3 HA, 2 TPS and 1 acid-etched surface), tends smaller affinity to eh surface with acids-etched surface. Pi was detected in 5 implants (2 Ticp, 2 HA and 1 acid-etched surface) in the period 0 and in 100% of implants in other periods. Fusobacterium sp. was detected in all the periods, tends a larger affinity to HA. Beta-hemolytic Streptococcus was detected in 6 implants (3 Ticp, 1 TPS and 2 HA) in the period 0 and 30, 26 and 24... (Complete abstract, click electronic address below). / Mestre