Osseoinductive elements around immediate implants for better osteointegration: a pilot study in foxhound dogs.

OBJECTIVE: The aim of this study was to evaluate the effects on osseointegration of topical applications of melatonin vs. vitamin D over surfaces of immediate implants. MATERIALS AND METHODS: Mandibular premolar distal roots (P2 , P3 , P4 ) were extracted bilaterally from six American Foxhound dogs. Three conical immediate implants were randomly placed bilaterally in each mandible. Three randomized groups were created: melatonin 5% test group (MI), vitamin D 10% test group (DI), and Control group implants (CI). Block sections were obtained after 12 weeks and processed for mineralized ground sectioning. Bone-to-implant contact (total BIC), new bone formation (NBF), inter-thread bone (ITB), and histological linear measurements (HLM) were assessed. RESULTS: At 12 weeks, all implants were clinically stable and histologically osseointegrated. Total BIC values were 49.20 ± 3.26 for the MI group, 49.86 ± 1.89 for DI group and 45.78 ± 4.21 for the CI group (P < 0.018) with statistically significant difference between the three groups. BIC percentage were 42.44 ± 2.18 for MI, 44.56 ± 1.08 for DI, and 41.95 ± 3.34 for CI groups respectively (P > 0.05). Inter-thread bone formation values were MI 17.56 ± 2.01, for DI 19.87 ± 0.92, and CI 14.56 ± 1.24 (P > 0.05). Statistically significant differences in peri-implant new bone formation were found between the three groups: MI 28.76 ± 1.98, DI 32.56 ± 1.11 and CI 25.43 ± 4.67, respectively (P < 0.045). Linear measurements showed that the MI group showed significantly less lingual crestal bone loss (CBL) (MI 0.59 ± 0.71), compared to DI (0.91 ± 1.21) and CI (0.93 ± 1.21) (P < 0.042), and less lingual peri-implant mucosa (PIM) (MI 3.11 ± 1.34),(DI 3.25 ± 0.18 compared with CI 3.54 ± 1.81 (P = 0.429). Linear measurements of buccal CBL showed significantly less buccal bone loss in test DI (0.36 ± 0.12) than CI (1.34 ± 1.23) and MI (1.11 ± 1.38) (P = 0.078). CONCLUSIONS: Within the limitations of this animal study, topical applications of 5% Melatonin or 10% vitamin D improved bone formation around implants placed immediately after extraction and helped to reduce CBL after 12 weeks osseointegration.

[On the history of cementless implants in extremity surgery]. / Über die Historie zementfreier Implantate in der Extremitätenchirurgie.

The aim of implantation of cementless hip prostheses is vital ingrowth of bone into the structured metal surface of the implant. Since the 1960s several implants with surfaces made of cobalt-based alloys have been produced for this purpose. In the 1980s a novel hip endoprosthesis with a spongiosa-metal surface was introduced. The three-dimensional ingrowth of bone tissue into the structured surface of the implant could be demonstrated both histologically and using scanning electron microscopy (SEM). These implants made of cobalt-based alloys can also be used in endo-exo prostheses. Titanium implants with a microstructured surface have also been used and very good osseintegration of the surface was also demonstrated by histomorphology. The optimization of the surface and design of the prostheses plays an increasingly more important role in the field of revision endoprostheses.

Effects of local application of the ankaferd blood stopper on osseointegration in three different surface titanium implants.

OBJECTIVE: Researchs of the effects of ankaferd blood stopper (ABS) on bone healing metabolism have revealed that it affects bone regeneration positively. The exact mechanism by which this positive effect on bone tissue metabolism is not known. The aim of this study is to biomechanic and biochemical analysis of the effects of the local ABS application on osseointegration of 3 different surfaced titanium implants. MATERIAL & METHODS: Spraque dawley rats were divided machined surfaced (MS) (n â€‹= â€‹10), sandblasted and large acid grid (SLA) (n â€‹= â€‹10) and resorbable blast material (RBM) (n â€‹= â€‹10) surfaced implants. ABS applied locally during the surgical application of the titanium implant before insertion in bone sockets. After 4 weeks experimental period the rats sacrificed and implants with surrounding bone tissues were removed to reverse torque analysis (Newton), blood samples collected to biochemical analysis (ALP, calcium, P). RESULTS: Biomechanic bone implant contact ratio detected higher in SLA surfaced implants compared with the RBM and controls (P â€‹< â€‹0,05). Phosphor levels detected lower in RBM implant group compared with the controls and SLA (P â€‹< â€‹0,05). Additionally; phosphor levels detected highly in controls compared with the RBM implants. CONCLUSION: According the biomechanical parameters ABS may be more effective in SLA and RBM surfaced implants when locally applied.

Facile surface functional polyetheretherketone with antibacterial and immunoregulatory activities for enhanced regeneration toward bacterium-infected bone destruction.

Existing biologically inert or unmodified implants to treat infectious bone defects or osteomyelitis still cannot effectively solve bacterial infection and osseointegration. In this work, a simple co-deposition strategy was developed to modify porous polyetheretherketone (PEEK) with improved antibacterial activity and controllable immunoregulatory ability. After PEEK was treated by H2SO4 to obtain porous PEEK (SPEEK), the self-polymerization of dopamine was operated on SPEEK in the solution of dopamine and gentamicin sulfate (GS) to prepare polydopamine (pDA) and GS layer-modified SPEEK (labeled as SPEEK-pDA-GS). The morphology, surface property, and molecular structure of SPEEK-pDA-GS were investigated. Besides the antibacterial property of SPEEK-pDA-GS ascribed to the successful immobilization of GS, SPEEK-pDA-GS exhibited promoted osseointegration through the results of mineralization, alkaline phosphatase (ALP) levels and osteogenic gene expression. Furthermore, the evaluation of the cell proliferation suggested that SPEEK-pDA-GS possessed the biocompatibility and the immunoregulatory ability that induced macrophages to anti-inflammatory M2 phenotype. Using rat as model, in vivo results containing X-ray, µ-CT, immunohistochemistry, and pathological analysis showed the excellent healing effect of SPEEK-pDA-GS on bone defect with infection with biological safety. This work illustrates a new insight into the simple and effective modification of PEEK and other implants with antibacterial, immunoregulatory, and osseointegration abilities for clinical requirement.

Progressive plateau root form dental implant osseointegration: A human retrieval study.

Although preclinical and sparse human histology retrieval studies have shown that the interface between implant and bone is constantly remodeling, no human retrieval database has been developed to determine the effect of functional loading time and other clinical/implant design variables on osseointegration. The present study tested the hypothesis that bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO) increase over functional loading time around dental implants. Due to prosthetic retreatment reasons, 93 human implant retrievals from the same manufacturer (Bicon LLC, Boston, MA, USA) were obtained over a period of approximately 15 years. The retrieved implants were under functional loading from 120 days to ∼18 years and were histomorphologic/metrically evaluated. BIC/BAFO were assessed as a function of multiple independent variables: implant surface type, diameter, length, jaw (maxilla/mandible), region (anterior/posterior), and time of functional loading. The results showed that both BIC and BAFO increased over time independently of implant design/clinical variables, supporting the postulated hypothesis.

Peri-Implant Bone Loss of External Hexagon and Morse Taper in Patients Wearing Immediately Loaded Overdentures

Abstract The aim of this study was to evaluate the peri-implant bone loss of External Hexagon (EH) and Morse Taper (MT) implants in patients wearing immediately loaded mandibular overdentures during a 1-year follow-up. This is a non-randomized controlled clinical trial including 18 MT and 22 EH implants. Periapical radiographs were taken after overdentures insertion and following 1 year. The peri-implant bone loss was assessed through digitalization and analysis of the radiographs in the software Corel DRAW X7. For this, measurement from implant platform to residual ridge at mesial and distal surfaces of each implant was conducted. The results showed high success rate in the groups EH (100%) and MT (94.4%). For peri-implant bone levels, it was found significant difference between the groups (p=0.032) and greater bone loss was observed in the group EH. In general, bone loss was 0.85mm (±0.82) for EH and 0.10mm (±1.0) for MT. It was concluded that greater bone loss occurred in the group EH in comparison to the group MT after a 1-year follow-up.

Resumo O objetivo deste estudo foi avaliar a perda óssea peri-implantar de implantes Hexágono Externo (HE) e Cone Morse (CM) em usuários de sobredentaduras mandibulares com carga imediata por um período de acompanhamento de 1 ano. Este é um ensaio clínico controlado não randomizado que inclui 18 CM e 22 HE. Radiografias periapicais foram obtidas na instalação das sobredentaduras e 1 ano após. A perda óssea peri-implante foi avaliada através da digitalização e análise das radiografias no software Corel DRAW X7. Para tal, a medição foi feita da plataforma dos implantes até a crista óssea nas faces mesiais e distais de cada implante. Os resultados mostraram alta taxa de sucesso nos grupos HE (100%) e CM (94,4%). Para os níveis ósseos peri-implantes, foi encontrada diferença significativa entre os grupos (p = 0,032) e maior perda óssea foi observada no grupo HE. Em média, a perda óssea foi de 0,85 mm (±0,82) para HE e de 0,10 mm (±1,0) para CM. Concluiu-se que uma maior perda óssea ocorreu no grupo HE em comparação com o grupo CM após um acompanhamento de 1 ano.