Article

Influence of lateral pressure to the implant bed on osseointegration: an experimental study in dogs.

Faculty of Dentistry of Araçatuba, UNESP - São Paulo State University, São Paulo, Brazil.
Clinical Oral Implants Research (Impact Factor: 3.43). 11/2010; 21(11):1264-70. DOI:10.1111/j.1600-0501.2010.01941.x
Source: PubMed

ABSTRACT To study osseointegration and bone-level changes at implants installed using either a standard or a reduced diameter bur for implant bed preparation.
In six Labrador dogs, the first and second premolars were extracted bilaterally. Subsequently, mesial roots of the first molars were endodontically treated and distal roots, including the corresponding part of the crown, were extracted. After 3 months of healing, flaps were elevated and recipient sites were prepared in all experimental sites. The control site was prepared using a standard procedure, while the test site was prepared using a drill with a 0.2 mm reduced diameter than the standard one used in the contra-lateral side. After 4 months of healing, the animals were euthanized and biopsies were obtained for histological processing and evaluation.
With the exception of one implant that was lost, all implants were integrated in mineralized bone. The alveolar crest underwent resorption at control as well as at test sites (buccal aspect ∼1 mm). The most coronal contact of bone-to-implant was located between 1.2 and 1.6 mm at the test and between 1.3 and 1.7 mm at the control sites. Bone-to-implant contact percentage was between 49% and 67%. No statistically significant differences were found for any of the outcome variables.
After 4 months of healing, lateral pressure to the implant bed as reflected by higher insertion torques (36 vs. 15 Ncm in the premolar and 19 vs. 7 Ncm in the molar regions) did not affect the bone-to-implant contact.

0 0
 · 
0 Bookmarks
 · 
59 Views
  • [show abstract] [hide abstract]
    ABSTRACT: To evaluate, on the base of cone beam computed tomography (CBCT) fractal dimension, bone quality changes surrounding the apical portion of immediate implants placed under higher insertion torque utilizing an undersized drilling technique. Three patients were enrolled in this study. Single implants were placed into fresh extraction sockets in the anterior maxilla and provisionalized immediately. Adequate stability was ensured on all the implants by a 28.5% undersizing of the apical portion of the osteotomy. Bone quality at the most apical 1.15 mm peri-implant bone portion were measured by CBCT at placement and after 6 months. This analysis was carried out by evaluating the box counting fractal dimension of 15 consecutive CBCT slices related to the most apical part of each implant. All the three implants were successful after an 18-month follow-up period. The mean fractal dimension at the implant apex exhibited a 3% increase 6 months following placement. Within the limitations of an explorative study, an undersized drilling resulting in high insertion torque would seem to induce no adverse changes in radiographic bone quality after 6 months of follow-up. The most favorable entity of drilling undersizing and its effect on peri-implant bone remodeling, should be evaluated on a larger patient population.
    Clinical Oral Implants Research 08/2011; 23(8):954-7. · 3.43 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: The behavior of fresh-frozen homologous bone (FFB) when used in combination with computer-guided implant surgery has not been investigated yet, and there is a lack of clinical evidence in the literature. The purpose of this retrospective study is to evaluate the implant survival and related fixed full-arch prostheses at the 1- to 5-year follow-up when performed with immediate function using a flapless surgical procedure and computer-aided technology (NobelGuide; Nobel Biocare AB, Goteborg, Sweden) in patients previously treated with FFB grafts. Furthermore, the related values of torque and complications observed were analyzed and discussed. Clinical charts of patients with edentulous arches treated with FFB grafts and NobelGuide system with at least 1 year follow-up were reviewed retrospectively.A total of 65 patients met the criteria of inclusion, receiving a total of 342 implants and 77 full-arch prostheses, with a mean follow-up of 32.87 months (range, 1-5 years). Survival of implants and prostheses was high, reaching 96.5% and 95%, respectively. Factors significantly related to failure of the implants were smoking, position of the implant as last distal abutment, and fracture of basal maxillary bone. Prostheses survival was influenced by bruxism, failure of multiple implants, and torque level of implant equal to 0 at implant insertion. All implants and prostheses failures occurred in the first year. A higher torque level at implant insertion did not correspond to a lower risk of implant failure.Within the limitations of our retrospective study, this treatment modality was predictable with high survival rates and high insertion torque. However, a few implant and prosthetic failures were found, together with several complications.
    The Journal of craniofacial surgery 11/2013; 24(6):e551-8. · 0.81 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: AIM: The first aim of the present experiment was to compare bone healing at implants installed in recipient sites prepared with conventional drills or a piezoelectric device. The second aim was to compare implant osseointegration onto surfaces with and without dendrimers coatings. MATERIAL AND METHODS: Six Beagles dogs were used in this study. Five implants with two different surfaces, three with a ZirTi(®) surface (zirconia sand blasted, acid etched), and two with a ZirTi(®) -modified surface with dendrimers of phosphoserine and polylysine were installed in the right side of the mandible. In the most anterior region (P2, P3), two recipient sites were prepared with drills, and one implant ZirTi(®) surface and one coated with dendrimers implants were installed at random. In the posterior region (P4 and M1), three recipient sites were randomly prepared: two sites with a Piezosurgery(®) instrument and one site with drill and two ZirTi(®) surface and one coated with dendrimers implants installed. Three months after the surgery, the animals were sacrificed for histological analysis. RESULTS: No complications occurred during the healing period. Three implants were found not integrated and were excluded from analysis. However, n = 6 was obtained. The distance IS-B at the buccal aspect was 2.2 ± 0.8 and 1.8 ± 0.5 mm, while IS-C was 1.5 ± 0.9 and 1.4 ± 0.6 mm at the Piezosurgery(®) and drill groups, respectively. Similar values were obtained between the dendrimers-coated and ZirTi(®) surface implants. The BIC% values were higher at the drill (72%) compared to the Piezosurgery(®) (67%) sites. The BIC% were also found to be higher at the ZirTi(®) (74%) compared to the dendrimers-coated (65%) implants, the difference being statistically significant. CONCLUSION: This study has revealed that oral implants may osseointegrate equally well irrespective of whether their bed was prepared utilizing conventional drills with abundant cooling or Piezosurgery(®) . Moreover, the surface coating of implants with dendrimers phosphoserine and polylysine did not improve osseointegration.
    Clinical Oral Implants Research 12/2012; · 3.43 Impact Factor

Full-text

View
21 Downloads
Available from
Aug 8, 2013