Immediate Implant Placement: Positives and Negatives

Morphometric analysis of maxillary alveolar regions for immediate implantation

PURPOSE

The purpose of this study was to provide an actual guideline in determining the shape, diameter, and position of the implant in immediate implantation by the measurement of the thickness of facial and palatal plate, the thickness of cortical bone on the facial and palatal plate, the diameter of the root, and the distance between the roots in the cadavers.

MATERIALS AND METHODS

The horizontal sections of 20 maxillae were measured and analyzed to obtain the average values. Resin blocks were produced and cut serially at 1 mm intervals from the cervical line to the root apex. Images of each section were obtained and the following measurements were performed: The thickness of the facial and palatal residual bone at each root surface, the thickness of the facial and palatal cortical bone at the interdental region, the diameter of all roots of each section on the faciopalatal and mesiodistal diameter, and the interroot distance. Three specimens with measurements close to the average values were chosen and 3-dimensional images were reconstructed.

RESULTS

The thickness of the facial and palatal cortical bone at the interdental region in the maxilla, the buccal cortical bone was thicker in the posterior region compared to the anterior region. The interroot distance of the alveolar bone thickness between the roots increased from anterior to posterior region and from coronal to apical in the maxilla.

CONCLUSION

In this study, the limited results of the morphometric analysis of the alveolar ridge using the sections of maxilla in the cadavers may offer the useful information when planning and selecting optimal implant for immediate implantation in the maxilla.

Measurement of primary and secondary stability of dental implants by resonance frequency analysis method in mandible

Background. There is no doubt that the success of the dental implants depends on the stability. The aim of this work was to measure the stability of dental implants prior to loading the implants, using a resonance frequency analysis (RFA) by Osstell mentor device. Methods. Ten healthy and nonsmoker patients over 40 years of age with at least six months of complete or partial edentulous mouth received screw-type dental implants by a 1-stage procedure. RFA measurements were obtained at surgery and 1, 2, 3, 4, 5, 7, and 11 weeks after the implant surgery. Results. Among fifteen implants, the lowest mean stability measurement was for the 4th week after surgery in all bone types. At placement, the mean ISQ obtained with the magnetic device was 77.2 with 95% confidence interval (CI) = 2.49, and then it decreased until the 4th week to 72.13 (95% CI = 2.88), and at the last measurement, the mean implant stability significantly (P value <0.05) increased and recorded higher values to 75.6 (95% CI = 1.88), at the 11th week. Conclusions. The results may be indicative of a period of time when loading might be disadvantageous prior to the 4th week following implant placement. These suggestions need to be further assessed through future studies.

Esthetic Evaluation of Single-Tooth Morse Taper Connection Implants Placed in Fresh Extraction Sockets or Healed Sites

The aim of this study was to compare the esthetic outcome of single implants placed in fresh extraction sockets with those placed in fully healed sites of the anterior maxilla. This retrospective study was based on data from patients treated with single-tooth Morse taper connection implants placed in fresh extraction sockets and in fully healed sites of the anterior maxilla. Only single implant treatments were considered with both neighboring teeth present. Additional prerequisites for immediate implant treatment were intact socket walls and a thick gingival biotype. The esthetic outcome was objectively rated using the pink esthetic/white esthetic score (PES/WES). The Mann-Whitney U test was used to compare the PES and the WES between the 2 groups. Twenty-two patients received an immediate implant, and 18 patients had conventional implant surgery. The mean follow-up was 31.09 months (SD 5.57; range 24–46) and 34.44 months (SD 7.10; range 24–48) for immediately and conventionally inserted implants, respectively. No implants were lost. All implants fulfilled the success criteria. The mean PES/WES was 14.50 (SD 2.52; range 9–19) and 15.61 (SD 3.20; range 8–20) for immediately and conventionally placed implants, respectively. Immediate implants had a mean PES of 7.45 (SD 1.62; range 4–10) and a mean WES of 7.04 (SD 1.29; range 5–10). Conventional implants had a mean PES of 7.83 (SD 1.58; range 4–10) and a mean WES of 7.77 (SD 1.66; range 4–10). The difference between the 2 groups was not significant. Immediate and conventional single implant treatment yielded comparable esthetic outcomes.

Immediate, non-submerged, root-analogue direct laser metal sintering (DLMS) implants: a 1-year prospective study on 15 patients

This study evaluated the 1-year survival and success rate of root-analogue direct laser metal sintering (DLMS) implants, placed into the extraction sockets of 15 patients. DLMS is a technology which allows solids with complex geometry to be fabricated by annealing metal powder microparticles in a focused laser beam, according to a computer-generated three-dimensional (3D) model; the fabrication process involves the laser-induced fusion of titanium microparticles, in order to build, layer-by-layer, the desired object. Cone-beam computed tomography (CBCT) acquisition and 3D image conversion, combined with the DLMS process, allow the fabrication of custom-made, root-analogue implants (RAIs). CBCT images of 15 non-restorable premolars (eight maxilla; seven mandible) were acquired and transformed into 3D models: from these, custom-made, root-analogue DLMS implants with integral abutment were fabricated. Immediately after tooth extraction, the RAIs were placed in the sockets and restored with a single crown. One year after implant placement, clinical and radiographic parameters were assessed: success criteria included absence of pain, suppuration, and exudation; absence of implant mobility and absence of continuous peri-implant radiolucency; distance between the implant shoulder and the first visible bone-to-implant contact <1.5 mm from initial surgery; and absence of prosthetic complications. At the 1-year follow-up, no implants were lost, for a survival rate of 100 %. All implants were stable, with no signs of infection. The good conditions of the peri-implant tissues were confirmed by the radiographic examination, with a mean DIB of 0.7 mm (±0.2). The possibility of fabricating custom-made, RAI DLMS implants opens new interesting horizons for immediate placement of dental implants.

Inhibition of Rac and ROCK signalling influence osteoblast adhesion, differentiation and mineralization on titanium topographies

Reducing the time required for initial integration of bone-contacting implants with host tissues would be of great clinical significance. Changes in osteoblast adhesion formation and reorganization of the F-actin cytoskeleton in response to altered topography are known to be upstream of osteoblast differentiation, and these processes are regulated by the Rho GTPases. Rac and RhoA (through Rho Kinase (ROCK)). Using pharmacological inhibitors, we tested how inhibition of Rac and ROCK influenced osteoblast adhesion, differentiation and mineralization on PT (Pre-treated) and SLA (sandblasted large grit, acid etched) topographies. Inhibition of ROCK, but not Rac, significantly reduced adhesion number and size on PT, with adhesion size consistent with focal complexes. After 1 day, ROCK, but not Rac inhibition increased osteocalcin mRNA levels on SLA and PT, with levels further increasing at 7 days post seeding. ROCK inhibition also significantly increased bone sialoprotein expression at 7 days, but not BMP-2 levels. Rac inhibition significantly reduced BMP-2 mRNA levels. ROCK inhibition increased nuclear translocation of Runx2 independent of surface roughness. Mineralization of osteoblast cultures was greater on SLA than on PT, but was increased by ROCK inhibition and attenuated by Rac inhibition on both topographies. In conclusion, inhibition of ROCK signalling significantly increases osteoblast differentiation and biomineralization in a topographic dependent manner, and its pharmacological inhibition could represent a new therapeutic to speed bone formation around implanted metals and in regenerative medicine applications.

Immediate Postextraction Implant Placement Using Plasma Rich in Growth Factors Technology in Maxillary Premolar Region: A New Strategy for Soft Tissue Management

Achieving an excellent aesthetic outcome in postextraction dental implant placement in the anterior maxilla is a challenging procedure for clinicians. In fact, there is an increased risk for soft tissue recession at the facial aspect which may require supplementary connective tissue grafts to accomplish the final aesthetic result. The aim of this case report is to describe a regenerative technique using autologous plasma rich in growth factors fibrin plug for preservation of soft tissue architecture around an implant immediately placed into an extraction site in the anterior maxilla. Such a procedure allowed for guided bone regeneration without the need for vertical releasing incisions and primary healing, thus showing a pleasant gingival contour at the facial aspect after a single stage surgery. Integrating this technique into common practice could provide important benefits for the patients regarding aesthetics, without any risk of infection or transmission of diseases.

Custom-made, root-analogue direct laser metal forming implant: a case report

In the last few years, the application of digital technology in dentistry has become widespread with the introduction of cone beam computed tomography (CBCT) scan technology, and considerable progress has been made in the development of computer-aided design/ computer-aided manufacturing (CAD/CAM) techniques, including direct laser metal forming (DLMF). DLMF is a technology which allows solids with complex geometry to be produced by annealing metal powder microparticles in a focused laser beam, according to a computer-generated three-dimensional (3D) model. For dental implants, the fabrication process involves the laser-induced fusion of titanium microparticles, in order to build, layer by layer, the desired object. At present, the combined use of CBCT 3D data and CAD/CAM technology makes it possible to manufacture custom-made, root-analogue implants (RAI) with sufficient precision. This report demonstrates the successful clinical use of a custom-made, root-analogue DLMF implant. CBCT images of a non-restorable right maxillary first premolar were acquired and transformed into a 3D model. From this model, a custom-made, root-analogue DLMF implant was fabricated. Immediately after tooth extraction, the RAI with a pre-operatively designed abutment was placed in the extraction socket and restored with a single crown. At the 1-year follow-up examination, the RAI showed a good functional and aesthetic integration. The introduction of DLMF technology signals the start of a new revolutionary era for implant dentistry as its immense potential for producing highly complex macro- and microstructures is receiving vast interest in different medical fields.

A novel root analogue dental implant using CT scan and CAD/CAM: selective laser melting technology

Direct laser metal forming (DLMF) is a new technique which allows solids with complex geometry to be produced by annealing metal powder microparticles in a focused laser beam, according to a computer-generated three-dimensional (3D) model. For dental implants, the fabrication process involves the laser-induced fusion of titanium microparticles, in order to build, layer by layer, the desired object. Modern computed tomography (CT) acquisition and 3D image conversion, combined with the DLMF process, allows the fabrication of custom-made, root-analogue implants (RAI), perfect copies of the radicular units that need replacing. This report demonstrates the successful clinical use of a custom-made, root-analogue DLMF implant. CT images of the residual non-restorable root of a right maxillary premolar were acquired and modified with specific software into a 3D model. From this model, a custom-made, root-analogue, DLMF implant was fabricated. Immediately after tooth extraction, the root-analogue implant was placed in the extraction socket and restored with a single crown. At the 1-year follow-up examination, the custom-made implant showed almost perfect functional and aesthetic integration. The possibility of fabricating custom-made, root-analogue DLMF implants opens new interesting perspectives for immediate placement of dental implants.

Designing a novel dental root analogue implant using cone beam computed tomography and CAD/CAM technology

OBJECTIVES

The study aim is to introduce a novel preemptively constructed dental root analogue implant (RAI) based on three-dimensional (3D) root surface models obtained from a cone beam computed tomography (CBCT) scan, computer aided designing and computer aided manufacturing technology.

MATERIALS & METHODS

One partially edentulous mandibular human cadaver was scanned with the Accuitomo 170 CBCT system. The scan volumes and datasets were used to create 3D surface models of the tooth. A 3D surface mesh of the tooth was stored as a standard triangulation language (STL) file. A high-end selective laser melting technology was used to fabricate the RAI from the STL file. The RAI was produced in a biocompatible titanium alloy (Ti6Al4V). Optical scanning technology was used to measure the RAI, as well as the natural tooth that was extracted. To validate the accuracy of the CBCT 3D root surface and the manufactured Titanium RAI, both surfaces were superimposed on the optical scan of the tooth, which served as the gold "reference" standard.

RESULTS

The differences between the RAI and the optical scan of the original tooth are most noticeable at the level of the apex and the cementenamel junction areas on the buccal and lingual side (divergence of more than 0.15 mm). Surface area measurements show an overall decrease in surface area of 6.33% for the RAI in comparison with the original tooth and an increase of 0.27% when comparing the 3D surface model with optical scan of the original tooth.

CONCLUSION

With the use of currently available technology it is very well feasible to preemptively create a custom RAI in titanium. However, clinical evidence evaluating the success of this novel dental implant approach is needed.

Single-tooth Morse taper connection implants placed in fresh extraction sockets of the anterior maxilla: an aesthetic evaluation

OBJECTIVE

The aim of this retrospective study was to evaluate the aesthetic outcome of single-tooth Morse taper connection implants placed in fresh extraction sockets of the anterior maxilla, by means of the pink aesthetic/white aesthetic score (PES/WES) index.

MATERIALS AND METHODS

Twenty-six adult patients (18 men, 8 women, aged between 20 and 62 years; average: 48.7 years) who were treated with an immediate, single-tooth Morse taper connection implant (Leone Implant System(R) , Florence, Italy) in the aesthetic area of the anterior maxilla, were enrolled in this retrospective study. An independent calibrated examiner applied the PES/WES index to 26 single-tooth implant-supported restorations, respectively, 3 months and 2 years after implant placement.

RESULTS

No implants were lost. All 26 anterior maxillary single-tooth implants fulfilled the established success criteria for dental implants with regard to osseointegration, including the absence of pain, suppuration, clinically detectable implant mobility, peri-implant radiolucency and prosthetic complications at the implant-abutment interface, with an overall implant-crown success of 100.0%. At the 2-year examination, the mean DIB was 0.44 ± 0.14 mm (95% CI: 0.41-0.47); the mean total PES/WES was 14.30 ± 2.78 (range 8-19); the mean PES was 7.30 ± 1.78 (range 4-10) and the mean WES was 7.00 ± 1.35 (range 4-10).

CONCLUSIONS

The immediate placement of single-tooth Morse taper connection implants in the anterior maxilla seems to represent a successful procedure, from an aesthetic point of view. Further studies are needed to evaluate the aesthetic outcome of single-tooth Morse taper connection implants placed in fresh extraction sockets of the anterior maxilla.