Nanocrystalline Hydroxyapatite Bone Substitute Leads to Sufficient Bone Tissue Formation Already after 3 Months: Histological and Histomorphometrical Analysis 3 and 6 Months following Human Sinus Cavity Augmentation.

Nanocrystalline Hydroxyapatite Bone Substitute Leads to Sufficient Bone Tissue Formation Already after 3 Months: Histological and Histomorphometrical Analysis 3 and 6 Months following Human Sinus Cavity Augmentation.

Clin Implant Dent Relat Res. 2012 Jan 17;

Authors: Ghanaati S, Barbeck M, Willershausen I, Thimm B, Stuebinger S, Korzinskas T, Obreja K, Landes C, Kirkpatrick CJ, Sader RA

Abstract

Purpose: In this study the de novo bone formation capacity of a nanocrystalline hydroxyapatite bone substitute was assessed 3 and 6 months after its insertion into the human sinus cavity. Materials and Methods: Sinus cavity augmentation was performed in a total of 14 patients (n = 7 implantation after 3 months; n = 7 implantation after 6 months) with severely atrophic maxillary bone. The specimens obtained after 3 and 6 months were analyzed histologically and histomorphometrically with special focus on bone metabolism within the residual bone and the augmented region. Results: This study revealed that bone tissue formation started from the bone-biomaterial-interface and was directed into the most cranial parts of the augmented region. There was no statistically significant difference in new bone formation after 3 and 6 months (24.89 ± 10.22% vs 31.29 ± 2.29%), respectively. Conclusions: Within the limits of the present study and according to previously published data, implant insertion in regions augmented with this bone substitute material could be considered already after 3 months. Further clinical studies with bone substitute materials are necessary to validate these findings.

PMID: 22251462 [PubMed - as supplied by publisher]

 

Fixed Implant-Retained Rehabilitation of the Edentulous Maxilla: 11-Year Results of a Prospective Study.

Fixed Implant-Retained Rehabilitation of the Edentulous Maxilla: 11-Year Results of a Prospective Study.

Clin Implant Dent Relat Res. 2012 Jan 17;

Authors: Mertens C, Steveling HG, Stucke K, Pretzl B, Meyer-Bäumer A

Abstract

Objectives: The aim of the present study was to assess long-term survival and success rates of implants in the edentulous maxilla restored with an implant-supported fixed prosthesis. Materials and Methods: Seventeen edentulous patients received six to eight implants and implant-supported fixed prostheses by one surgeon. Yearly recalls were conducted by two examiners over a period of 11 years. Survival and success rates (biological complications) were determined; marginal bone loss was examined radiographically. Furthermore, microbiological tests as well as test for interleukin-1 composite genotype were assessed and potential risk factors were evaluated. Results: After a mean time of 11.26 years, 15 patients of 17 could be reexamined. Out of 94 implants, three were lost in one patient. Mean marginal bone loss reached 0.88 mm, two patients (at seven implants) showed bone loss of ≥3.2 mm. Survival rate of implants reached 96.8%. Success rates on implant level hit 92.6% according to the criteria of Albrektsson and colleagues and 83.0% in accordance with Karoussis and colleagues. One prosthesis had to be renewed. Conclusion: Within the limitation of this study, restoration of the edentulous maxilla with an implant-supported fixed prosthesis represents an effective tool for rehabilitation over a period of 11 years.

PMID: 22251485 [PubMed - as supplied by publisher]

 



Conventional Multi-Slice Computed Tomography (CT) and Cone-Beam CT (CBCT) for Computer-Assisted Implant Placement. Part I: Relationship of Radiographic Gray Density and Implant Stability.

Conventional Multi-Slice Computed Tomography (CT) and Cone-Beam CT (CBCT) for Computer-Assisted Implant Placement. Part I: Relationship of Radiographic Gray Density and Implant Stability.

Clin Implant Dent Relat Res. 2012 Jan 17;

Authors: Arisan V, Karabuda ZC, Avsever H, Ozdemir T

Abstract

Purpose: The relationship of conventional multi-slice computed tomography (CT)- and cone beam CT (CBCT)-based gray density values and the primary stability parameters of implants that were placed by stereolithographic surgical guides were analyzed in this study. Materials and Methods: Eighteen edentulous jaws were randomly scanned by a CT (CT group) or a CBCT scanner (CBCT group) and radiographic gray density was measured from the planned implants. A total of 108 implants were placed, and primary stability parameters were measured by insertion torque value (ITV) and resonance frequency analysis (RFA). Radiographic and subjective bone quality classification (BQC) was also classified. Results were analyzed by correlation tests and multiple regressions (p < .05). Results: CBCT-based gray density values (765 ± 97.32 voxel value) outside the implants were significantly higher than those of CT-based values (668.4 ± 110 Hounsfield unit, p < .001). Significant relations were found among the gray density values outside the implants, ITV (adjusted r(2)  = 0.6142, p = .001 and adjusted r(2)  = 0.5166, p = .0021), and RFA (adjusted r(2)  = 0.5642, p = .0017 and adjusted r(2)  = 0.5423, p = .0031 for CT and CBCT groups, respectively). Data from radiographic and subjective BQC were also in agreement. Conclusions: Similar to the gray density values of CT, that of CBCT could also be predictive for the subjective BQC and primary implant stability. Results should be confirmed on different CBCT scanners.

PMID: 22251553 [PubMed - as supplied by publisher]

 

Immediate Occlusal Loading of NanoTite™ Tapered Implants: A Prospective 1-Year Clinical and Radiographic Study.

Immediate Occlusal Loading of NanoTite™ Tapered Implants: A Prospective 1-Year Clinical and Radiographic Study.

Clin Implant Dent Relat Res. 2012 Jan 17;

Authors: Ostman PO, Wennerberg A, Ekestubbe A, Albrektsson T

Abstract

Background: During the last decade, high success rates have been reported for implants placed with immediate loading procedures, especially when bone quality and quantity provide good implant stability. In many of these studies, straight-walled implants with moderately rough surfaces were employed. Tapered implants are becoming increasingly more popular due to standardized drilling protocols and reports of high initial primary stability. Purpose: The aim of the present prospective, single center clinical study was to evaluate surface topographical analysis and the clinical and radiographic outcomes of the NanoTite™ (BIOMET 3i, Palm Beach Gardens, FL, USA) Tapered Implant when used for immediate loading of fixed prostheses and single-tooth restorations. Materials and Methods: Forty-two patients who needed implant treatment and met admission criteria agreed to participate in the study and were consecutively enrolled. Surgical implant placement requirements consisted of a final torque of a least 30 Ncm prior to final seating and an implant stability quotient above 55. A total of 139 NanoTite Tapered implants (112 maxillary and 27 mandibular) were placed by one investigator, and the majority of these implants (n = 77/55%) were placed in posterior regions, and in soft bone (n = 90/65%). A total of 57 prosthetic constructions were evaluated consisting of 20 single-tooth restorations, 30 fixed partial dentures, and 7 complete, fixed maxillary restorations. Radiographs were taken at baseline and at 12 months of follow-up. Results: Of the 139 study implants, one implant failure was declared. The overall cumulative survival rate at 1 year is 99.4%. Mean marginal bone resorption is 1.01 mm (SD 0.85) during the first year of function. Conclusion: Although limited to the short follow-up, immediate loading of NanoTite Tapered implants seems to be a viable option in implant rehabilitation, when insertion torque of at least 30 Ncm is achieved. Further studies are needed to authenticate the finding of this study.

PMID: 22251669 [PubMed - as supplied by publisher]

 

Clinical, Aesthetic, and Patient-Related Outcome of Immediately Loaded Single Implants in the Anterior Maxilla: A Prospective Study in Extraction Sockets, Healed Ridges, and Grafted Sites.

Clinical, Aesthetic, and Patient-Related Outcome of Immediately Loaded Single Implants in the Anterior Maxilla: A Prospective Study in Extraction Sockets, Healed Ridges, and Grafted Sites.

Clin Implant Dent Relat Res. 2012 Jan 17;

Authors: Raes F, Cosyn J, De Bruyn H

Abstract

Purpose: The objective of this prospective clinical study was to document the overall treatment outcome of immediately loaded single Astra Tech Osseospeed™ (Astra Tech AB, Mölndal, Sweden) implants placed in extraction sockets, healed ridges, and grafted sites. Materials and Methods: Forty-eight patients in need of a single implant in the anterior maxilla (15-25) were recruited. Patients were allocated to a conventional implant treatment (CIT) or immediate implant treatment (IIT) group on the basis of specific criteria. If the buccal bone plate was damaged or missing upon tooth removal, patients were allocated to a grafted implant treatment (GIT) group. Irrespective of the treatment concept, implants were immediately provisionalized. Hard and soft tissue alterations, aesthetic parameters (pink and white esthetic scores, [PES and WES]) and patient’s opinion (Oral Health Impact Profile [OHIP-14] questionnaires) were registered at different time points. Results: After 1 year of function, the overall implant survival rate was 98% with one failure following IIT. The mean bone level to the implant-abutment interface was 0.65 (SD 0.79), 0.85 (SD 0.64), and 0.56 mm (SD 0.44) for CIT, IIT, and GIT. Complete papilla loss was rare following either strategy. Mean midfacial recession amounted to 1.00 (SD 1.15), 0.12 (SD 0.78), and 0.49 mm (SD 0.82) for CIT, IIT, and GIT, respectively. The aesthetic outcome showed a mean PES of 10.30 (SD 1.89) and mean WES of 7.11 (SD 2.14), all patients considered. Patient’s satisfaction showed a significant improvement after 1 year of function on all seven domains (p < .001). Conclusions: This prospective study showed that single implants clinically and aesthetically perform well under immediate non-occlusal loading conditions in the premaxilla. In this context, it is of pivotal importance to stress that patients were carefully selected for IIT and GIT.

PMID: 22251879 [PubMed - as supplied by publisher]

 



Electrical Mallet Provides Essential Advantages in Maxillary Bone Condensing. A Prospective Clinical Study.

Electrical Mallet Provides Essential Advantages in Maxillary Bone Condensing. A Prospective Clinical Study.

Clin Implant Dent Relat Res. 2012 Jan 11;

Authors: Crespi R, Capparè P, Gherlone E

Abstract

Purpose: The aim of this study was to compare the use of hand mallet versus electrical mallet (magnetic mallet, Meta-Ergonomica, Turbigo, Milan, Italy) in osteotome-assisted surgery for condensing bone procedure in edentulous molar and premolar maxillary regions. Materials and Methods: Patients edentulous in maxillary premolar and molar regions with type 3 or 4 bone were enrolled in this prospective clinical study. The patients were randomly divided in two groups: in the test group, the implant site was prepared with osteotomes pushed by magnetic mallet, while in the control group, the implant site was performed with osteotomes pressed by hand mallet. Intraoral digital radiographic measurements were reported at 6, 12, and 24 months. Results: Thirty-six patients were enrolled in the study. Eighteen patients (21 women and 15 men) were included in the test group and 18 patients in the control group. The mean patient age was 56.1 years (range 41-71 years). Fifty dental implants were placed. In 10 cases, five in control and five in test group, sinus elevation was performed. After 24 months follow-up, a survival rate of 96.0% was reported. In the control group, two patients claimed benign paroxysmal positional vertigo following the use of osteotomes with hand hammer. Marginal bone levels remained stable over time for both groups, and not statistically significant differences were found. After 12 months, the bone height incremented in both groups and, at 24 months, was stable. Statistical analysis reported not statistically significant differences between test and control group. Conclusions: These results demonstrated a stable marginal bone levels over time and a significant increase in bone height between 6 and 12 months in osteotome technique (not sinus elevation). The use of magnetic mallet provided some essential clinical advantages during surgical procedure in comparison with hand mallet.

PMID: 22235762 [PubMed - as supplied by publisher]

 

Conventional Multi-Slice Computed Tomography (CT) and Cone-Beam CT (CBCT) for Computer-Aided Implant Placement. Part II: Reliability of Mucosa-Supported Stereolithographic Guides.

Conventional Multi-Slice Computed Tomography (CT) and Cone-Beam CT (CBCT) for Computer-Aided Implant Placement. Part II: Reliability of Mucosa-Supported Stereolithographic Guides.

Clin Implant Dent Relat Res. 2012 Jan 11;

Authors: Arisan V, Karabuda ZC, Pişkin B, Ozdemir T

Abstract

Purpose: Deviations of implants that were placed by conventional computed tomography (CT)- or cone beam CT (CBCT)-derived mucosa-supported stereolithographic (SLA) surgical guides were analyzed in this study. Materials and Methods: Eleven patients were randomly scanned by a multi-slice CT (CT group) or a CBCT scanner (CBCT group). A total of 108 implants were planned on the software and placed using SLA guides. A new CT or CBCT scan was obtained and merged with the planning data to identify the deviations between the planned and placed implants. Results were analyzed by Mann-Whitney U test and multiple regressions (p < .05). Results: Mean angular and linear deviations in the CT group were 3.30° (SD 0.36), and 0.75 (SD 0.32) and 0.80 mm (SD 0.35) at the implant shoulder and tip, respectively. In the CBCT group, mean angular and linear deviations were 3.47° (SD 0.37), and 0.81 (SD 0.32) and 0.87 mm (SD 0.32) at the implant shoulder and tip, respectively. No statistically significant differences were detected between the CT and CBCT groups (p = .169 and p = .551, p = .113 for angular and linear deviations, respectively). Conclusions: Implant placement via CT- or CBCT-derived mucosa-supported SLA guides yielded similar deviation values. Results should be confirmed on alternative CBCT scanners.

PMID: 22235792 [PubMed - as supplied by publisher]

 

Correlation of Platelet Growth Factor Release in Jawbone Defect Repair – A Study in the Dog Mandible.

Correlation of Platelet Growth Factor Release in Jawbone Defect Repair – A Study in the Dog Mandible.

Clin Implant Dent Relat Res. 2012 Jan 11;

Authors: Thor AL, Hong J, Kjeller G, Sennerby L, Rasmusson L

Abstract

Background: Platelet concentrate/platelet-rich plasma (PRP) has been studied extensively in various experimental models and there is some agreement among workers to its early effect in bone regeneration and healing. We have earlier showed in vitro that titanium in whole blood activates the thrombogenic response to a higher degree than PRP and that a fluoridated test surface augmented the effect compared with control. Purpose: We designed this study to evaluate the effect of PRP and whole blood on bone regeneration in a dog implant defect model and, in addition, the effect of a test surface modified in hydrofluoric acid. A correlation attempt between platelet count, release of growth factors, and bone regeneration was made. Materials and Methods: Six dogs were used and simultaneously with the experimental surgery and implant installation, autologous PRP was prepared. Defects were prepared (6 mm in diameter and 5 mm deep), and implants were installed (TiO(2) gritblasted and hydrofluoric acid treated [test] or TiO(2) gritblasted [control], 5 mm in diameter and 9 mm long) in defects filled with either PRP or whole blood. Randomization of sides between PRP and whole blood, and sites for test and control implants were made. Blood samples were collected from PRP and whole blood. The dogs were killed after 5 weeks of healing, and samples with implants and surrounding bone were collected and processed for analysis. Enzyme linked immunosorbent assays were used for detection of growth factors in PRP. Results: The mean increase of platelet count was 424% in PRP. A correlation for platelet counts and transforming growth factor β was found in each dog (r(2)  = 0.857). Approximately 50% of the region of interest (ROI) in the defects was filled with new bone after 5 weeks. No difference could be observed in ROI by using PRP or whole blood in the defects regarding new bone formation, bone in contact with implant, or distance to first bone contact. However, the fluoridated implants exhibited more new bone formation (p = .03) compared with control, regardless of comparing PRP or whole blood, and also displayed a shorter distance from first bone contact to the margin of the bone envelope (p = .05). Conclusions: Platelet concentrate/PRP failed to show more new bone regeneration in a peri-implant defect model compared with whole blood. Implants treated with hydrofluoric acid displayed higher percentages of bone fill in the defect.

PMID: 22235990 [PubMed - as supplied by publisher]

 

Randomized Controlled Trial to Compare Two Bone Substitutes in the Treatment of Bony Dehiscences.

Randomized Controlled Trial to Compare Two Bone Substitutes in the Treatment of Bony Dehiscences.

Clin Implant Dent Relat Res. 2012 Jan 11;

Authors: Van Assche N, Michels S, Naert I, Quirynen M

Abstract

Aim: This in vivo split-mouth randomized controlled trial compared a synthetic bone substitute with a bovine bone mineral to cover bone dehiscences after implant insertion. Materials and Methods: Fourteen patients received four to six implants to support an overdenture. Two comparable dehiscences within the same patient were first covered with a layer of autogenous bone, followed by a layer of either Bio-Oss® (group 1; Geistlich Pharma AG, Wolhusen, Switzerland) or Straumann BoneCeramic® (group 2; Institut Straumann AG, Basel, Switzerland) and sealed by a resorbable membrane. The change in vertical dimension of the defect was measured at implant placement and at abutment connection (6.5 months). Clinical and radiological parameters were evaluated up to 1 year of loading. Results: The vertical size of the defect at surgery was 6.4 ± 1.6 mm for group 1 and 6.4 ± 2.2 mm for group 2 sites, measured from the implant shoulder. After 6.5 months, the depth of the defect was reduced to 1.5 ± 1.2 mm and 1.9 ± 1.2 mm for group 1 and group 2 sites, respectively (p > 0.05). No implants failed during follow-up. Mean marginal bone loss over the SLActive surface was 0.94 mm (group 1), 0.81 mm (group 2), and 0.93 mm (group 3, no dehiscence) after 1 year of loading. Conclusion: Both bone substitutes behaved equally effectively.

PMID: 22236044 [PubMed - as supplied by publisher]

 

Immediate Postextractive Dental Implant Placement with Immediate Loading on Four Implants for Mandibular-Full-Arch Rehabilitation: A Retrospective Analysis.

Immediate Postextractive Dental Implant Placement with Immediate Loading on Four Implants for Mandibular-Full-Arch Rehabilitation: A Retrospective Analysis.

Clin Implant Dent Relat Res. 2012 Jan 11;

Authors: Mozzati M, Arata V, Gallesio G, Mussano F, Carossa S

Abstract

Background: To date, only few studies have reported on the clinical outcomes of immediate postextraction implant placement and immediate loading. Purpose: The purpose of this retrospective study was to report the results of immediately loading four implants placed in fresh extraction sockets in the mandible after a follow-up of 24 months. Materials and Methods: Between January 2001 and January 2009, 50 patients (28 women and 22 men, average age 54 years), had 347 teeth extracted and a total of 200 dental implants placed in the mandible. The patients received a provisional fixed bridge the same day and a permanent one 3 months later. Clinical checkups were performed after 1, 2, 3, 6, 12, and 24 months. Marginal bone measurements were made in intraoral radiographs taken 1 day after surgery and after 1 year. A questionnaire was used to evaluate self-perceived factors related to comfort, aesthetics, and function. Results: All bridges were stable and no implant failures were recorded during the follow-up, giving a survival rate of 100%, at 2 years. The marginal bone loss amounted to 1.33 ± 0.36 mm after 1 year and 1.48 ± 0.39 mm after 2 years. Ten patients showed prosthetic complications with the provisional bridge, but all the definitive prostheses remained stable throughout the study period without any complications. The patients reported satisfaction with the treatment. Conclusions: The present retrospective study showed that immediate loading of four implants immediately placed in extraction sockets is a valid treatment modality for the totally edentulous mandible.

PMID: 22236085 [PubMed - as supplied by publisher]