umu.sePublications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
On healing of titanium implants in iliac crest bone grafts
Umeå University, Faculty of Medicine, Odontology.
2006 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Bone grafts and titanium implants are commonly used for surgical/prosthetic rehabilitation of the atrophic edentulous maxilla. The factors which influence bone graft healing and implant integration are not sufficiently understood.

The aim of this dissertation was to evaluate autogenous bone grafting and delayed placement of titanium endosteal implants for reconstruction of the atrophic maxilla, including the effects of different patient factors on bone graft healing and integration of titanium implants into grafted bone.

A total of 46 patients with severe maxillary atrophy received onlay- (n=35) or interpositional bone grafts (n=11) and 6 mo. later received 341 titanium endosteal implants. All bone grafts were harvested from the iliac crest. All patients received fixed dental bridges and were followed clinically and with radiographical examinations for 3 yr.

In Papers I and II, a total of 68 titanium microimplants were placed and retrieved from the bone grafts at various time points for histological analysis of the bone graft-implant interface. Integration was better after 6 mo. healing than placement in conjunction with bone grafting. Implant integration was similar for the two bone-grafting techniques.

In Papers III and IV, originally including 29 patients and 222 implants, implant stability was measured with resonance frequency analysis (RFA) at placement, abutment connection, after 6 mo. of loading (III) and after 3 yr. of loading (IV). Ten non-grafted patients measured at the same time points were used as controls (III). RFA showed equal implant stability in grafted bone vs. non-grafted bone (III). Stability did not change from the 6-mo. to the 3-yr. control. Cumulative survival was 90% after 3 yr. (21 implants failed). Thirteen implants were lost prior to loading and 8 during functional loading. The group of failed implants showed a lower primary RFA stability than those that remained stable for 3 yr. All patients received and maintained a fixed dental bridge throughout the study.

In Paper V, the graft volume changes (GVC) during the 6-mo. healing period prior to implant placement were studied in 30 patients using computerized tomography. Blood samples were taken from 25 patients in conjunction with bone grafting and were analysed for 13 haematological factors. Bone mineral density (BMD) was measured in 21 patients. Biopsies of the bone grafts were analysed for bone volume fraction (BVF). GVC (loss) was correlated with decreased BMD of the lumbar vertebrae L2-L4. There was no correlation between the haematological factors and GVC. Implant failure was not correlated with BMD, BVF or GVC.

This dissertation shows that surgical/prosthetic rehabilitation of the atrophic edentulous maxilla with autogenous iliac crest bone grafts and delayed placement of titanium implants after 6 mo. of graft healing is effective, reproducible and functional. RFA at placement may be able to predict later implant failure.

Place, publisher, year, edition, pages
2006. , 76 p.
Series
Umeå University odontological dissertations, ISSN 0345-7532 ; 94
Keyword [en]
Surgery, Edentulous atrophic maxilla, Autogenous bone graft, Endosteal implants, Microimplants, Resonance frequency analysis, Implant survival, Graft volume changes
Keyword [sv]
Kirurgi
Research subject
Odontology
Identifiers
URN: urn:nbn:se:umu:diva-914ISBN: 91-7264-199-1 (print)OAI: oai:DiVA.org:umu-914DiVA: diva2:145024
Public defence
2006-11-24, Sal B, 9 tr, By 1D, Tandläkarhögskolan, Umeå, 13:00 (English)
Opponent
Supervisors
Available from: 2006-11-03 Created: 2006-11-03 Last updated: 2009-10-29Bibliographically approved
List of papers
1. Simultaneous or delayed placement of titanium implants in free autogenous iliac bone grafts: Histological analysis of the bone graft-titanium interface in 10 consecutive patients
Open this publication in new window or tab >>Simultaneous or delayed placement of titanium implants in free autogenous iliac bone grafts: Histological analysis of the bone graft-titanium interface in 10 consecutive patients
1999 (English)In: International Journal of Oral and Maxillofacial Surgery, ISSN 0901-5027, Vol. 28, no 1, 31-37 p.Article in journal (Refereed) Published
Abstract [en]

The aim of the present study was to histologically analyse the bone graft-titanium implant interface after six and twelve months of healing for a simultaneous approach and after six months for a delayed approach. For this purpose, screw-shaped c.p. titanium microimplants, 2 mm in diameter and 5 mm long, were placed and retrieved at different time intervals in ten consecutive patients with severely resorbed maxillae and treated with iliac cortico-cancellous bone grafts and titanium implants in a two-stage procedure. The histomorphometrical analyses of ground sections of the specimens showed a higher degree of bone-implant contact and more bone filling the implant threads in the delayed approach microimplants. This was probably due to the partly revascularized grafted bone in the delayed approach being able to respond to the surgical trauma, resulting in interfacial bone formation. It is concluded that the results from the present study favour the use of a delayed approach when using free autogenous bone grafts and titanium implants for reconstruction of the severely atrophied maxilla.

National Category
Dentistry
Identifiers
urn:nbn:se:umu:diva-5490 (URN)10.1034/j.1399-0020.1999.280108.x (DOI)10065646 (PubMedID)
Available from: 2006-11-03 Created: 2006-11-03 Last updated: 2010-04-13Bibliographically approved
2. A histomorphometric comparison of the bone graft-titanium interface between interpositional and onlay/inlay bone grafting techniques.
Open this publication in new window or tab >>A histomorphometric comparison of the bone graft-titanium interface between interpositional and onlay/inlay bone grafting techniques.
2006 (English)In: International Journal of Oral & Maxillofacial Implants, ISSN 0882-2786, E-ISSN 1942-4434, Vol. 21, no 1, 52-62 p.Article in journal (Refereed) Published
Abstract [en]

PURPOSE: To analyze the bone graft-implant interface of titanium microimplants (MIs) placed at the time of bone grafting or after a healing period of 6 months and retrieved after another 6 to 14 months of healing. Integration of MIs placed in interpositional bone grafts (IBGs) in conjunction with a Le Fort I osteotomy was compared with the integration of those placed in onlay/inlay bone grafts (OBGs). MATERIALS AND METHODS: The severely atrophied edentulous maxillae of 23 patients (14 women, 9 men) were restored with autogenous bone grafts (either IBG [n=8] or OBG [n=15]) and titanium implants. Six-month periods were allowed between grafting, implant placement, and abutment connection. The bone-implant interface was studied histologically with the use of unloaded titanium MIs. RESULTS: Sixty-eight MIs were either (1) placed simultaneously with grafting and retrieved after 6, 12, or 14 months or (2) placed after 6 months of healing and retrieved after another 6 to 8 months. Histomorphometry indicated equal degrees of osseointegration for the 2 intraoral reconstruction techniques when looking at bone-implant contact, bone area in threads, and newly formed bone (NFB) (Student t test for unpaired observations). There was a significant difference between simultaneous and delayed implant placement with respect to BIC and NFB (Student t test for paired observations). Three additional MIs placed in the nongrafted residual alveolar ridge and retrieved after 6 months showed significantly more bone in threads and NFB (Student t test for paired observations; P = .003 and P = .009, respectively) compared to MIs placed at graft placement (6 months' healing). DISCUSSION: Timing of implant placement appeared more important than healing time or surgical technique. The delayed approach resulted in better implant integration, probably because of the initial revascularization of the graft. CONCLUSIONS: Implant integration was similar in the IBG and OBG groups. Placement of MIs after an initial healing period of 6 months resulted in better integration than placement simultaneously with grafting.

Keyword
Odontologi
National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:umu:diva-12368 (URN)16519182 (PubMedID)
Available from: 2007-11-15 Created: 2007-11-15 Last updated: 2016-10-26Bibliographically approved
3. Monitoring of implant stability in grafted bone using resonance frequency analysis: A clinical study from implant placement to 6 months of loading.
Open this publication in new window or tab >>Monitoring of implant stability in grafted bone using resonance frequency analysis: A clinical study from implant placement to 6 months of loading.
2005 (English)In: International Journal of Oral and Maxillofacial Surgery, ISSN 0901-5027, E-ISSN 1399-0020, Vol. 34, no 1, 45-51 p.Article in journal (Refereed) Published
Abstract [en]

The aim of this prospective study was to compare implants placed in grafted and normal non-grafted maxilla by means of resonance frequency analysis (RFA), clinical stability and implant failure. Twenty-nine patients with severe atrophy of the edentulous maxilla were treated with autogenous bone grafts as onlay (24 patients) or as interpositional grafts in conjunction with a Le Fort I osteotomy (five patients) 6 months prior to placement of 222 implants. Ten non-grafted patients treated with 75 Brånemark implants in the edentulous maxillae served as a control group. RFA was performed at implant placement, abutment connection and after 6 months of bridge loading. Seventeen (8%) implants were lost in the grafted bone and one (1%) in normal bone. RFA revealed a similar pattern in both grafted and normal maxillae, i.e. increasing resonance frequency (RF) with time (Wilcoxon Signed Rank test for paired data). Twenty implants that were rotation mobile (low primary stability) at the time of insertion showed a significantly lower value at implant placement according to RFA (Mann-Whitney U-test, P = 0.020). The RF for the failed implants revealed a tendency towards lower values (Mann-Whitney U-test, P = 0.072), compared to the successful implants. It is concluded that implants placed in grafted bone when using a two-stage technique achieve a stability similar to that of implants placed in normal non-grafted bone.

National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:umu:diva-17697 (URN)10.1016/j.ijom.2004.03.007 (DOI)15617966 (PubMedID)
Available from: 2007-11-15 Created: 2007-11-15 Last updated: 2016-10-26Bibliographically approved
4. Reconstruction of the atrophic edentulous maxilla with free iliac crest grafts and implants: a 3-year report of a prospective clinical study.
Open this publication in new window or tab >>Reconstruction of the atrophic edentulous maxilla with free iliac crest grafts and implants: a 3-year report of a prospective clinical study.
2007 (English)In: Clinical Implant Dentistry and Related Research, ISSN 1523-0899, E-ISSN 1708-8208, Vol. 9, no 1, 46-59 p.Article in journal (Refereed) Published
Abstract [en]

PURPOSE: The purpose of this study was to perform a longitudinal follow-up study of implant stability in grafted maxillae with the aid of clinical, radiological, and resonance frequency analysis (RFA) parameters. MATERIALS AND METHODS: The atrophic edentulous maxillae in 29 patients were reconstructed with free iliac crest grafts using onlay/inlay or interpositional grafting techniques. The endpoint of the resorption pattern in the maxilla determined the grafting technique used. Endosteal implants were placed after 6 months of bone-graft healing. Implant stability was measured four times using RFA: when the implants were placed, after 6 to 8 months of healing, after 6 months and 3 years of bridge loading. Individual checkups were performed at the two later RFA registrations after removal of the supraconstructions (Procera Implant Bridge, Nobel Biocare AB, Goteborg, Sweden). Radiological follow up of marginal bone level was performed annually. RESULTS: Twenty-five patients remained for the follow-up period. A total of 192 implants were placed and with a survival rate of 90% at the 3-year follow up. Women and an implant position with a class 6 resorption prior to reconstruction were factors with significant increased risk for implant failure (multivariate logistic regression). Twelve of the 20 failed implants were lost before loading (early failures). The change in the marginal bone level was 0.3 +/- 0.3 mm between baseline (bridge delivery) and the 3-year follow up. The implant stability quotient (ISQ) value for all implants differed significantly between abutment connection (60.2 +/- 7.3) and after 6 months of bridge loading (62.5 +/- 5.5) (Wilcoxon signed ranks test for paired data, p=.05) but were nonsignificant between 6 months of bridge loading and 3 years of bridge loading (61.8 +/- 5.5). There was a significant difference between successful and failed implants when the ISQ values were compared for individual implants at placement (Mann-Whitney U test, p=.004). All 25 patients were provided with fixed implant bridges at the time of the 3-year follow up. CONCLUSION: This clinical follow up using radiological examinations and RFA measurements indicates a predictable and stable long-term result for patients with atrophic edentulous maxillae reconstructed with autogenous bone and with delayed placement of endosteal implants. The ISQ value at the time of placement can probably serve as an indicator of level of risk for implant failure.

Keyword
Odontologi
National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:umu:diva-12369 (URN)10.1111/j.1708-8208.2007.00034.x (DOI)17362496 (PubMedID)
Available from: 2007-11-15 Created: 2007-11-15 Last updated: 2016-10-26Bibliographically approved
5. Influence of bone density and bone metabolic factors on the healing of bone grafts and implant failure in reconstruction of maxillary atrophy
Open this publication in new window or tab >>Influence of bone density and bone metabolic factors on the healing of bone grafts and implant failure in reconstruction of maxillary atrophy
(English)Manuscript (Other academic)
National Category
Dentistry
Identifiers
urn:nbn:se:umu:diva-5494 (URN)
Available from: 2006-11-03 Created: 2006-11-03 Last updated: 2010-06-08Bibliographically approved

Open Access in DiVA

fulltext(2198 kB)3722 downloads
File information
File name FULLTEXT01.pdfFile size 2198 kBChecksum SHA-1
a132db03844142e4bf85b0608db8af735477c9774acc97994b4b502ec652d8855b894805
Type fulltextMimetype application/pdf

By organisation
Odontology

Search outside of DiVA

GoogleGoogle Scholar
Total: 3722 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 1777 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf