Mark Bischof

Osteotome sinus floor elevation technique without grafting material: 3-year results of a prospective pilot study

OBJECTIVE In a prospective pilot study, short< or =10 mm ITI-SLA implants were placed in the resorbed posterior maxilla by means of an osteotome sinus floor elevation (OSFE) procedure without grafting material. This paper presents 3-year data assessing bone-level changes around implants. MATERIAL AND METHODS Twenty-five implants were placed in 17 patients to rehabilitate 16 molar and nine premolar sites. The mean residual bone height (RBH) was 5.4 +/- 2.3 mm. A healing period of 3-4 months was allowed before abutment tightening. Most implants (21/25) were 10 mm long, and the others were 8 and 6 mm long. At the 3-year control, endo-sinus bone gain, implant length protruding into the sinus and crestal bone loss (CBL) were measured on periapical radiographs. RESULTS All implants fulfilled the survival criteria. Despite the absence of grafting material, implants were embedded into newly formed bone tissue. All implants gained endo-sinus bone; the mean gained bone was 3.1 +/- 1.5 mm. The residual protrusion length decreased from 4.9 +/- 2.1 to 1.8 +/- 2.1 mm. CBL was 0.9 +/- 0.8 mm. CONCLUSIONS This study confirms that the OSFE procedure without grafting material is sufficient to create bone beyond the natural limit of the sinus. On the mid-term of 3 years, the technique was found to be predictable in the posterior maxilla when the RBH is limited. Implants gained endo-sinus bone despite the lack of grafting material. Bone gain was still improving over the first-year control. No shrinkage of the augmented area was observed.

Osteotome sinus floor elevation technique without grafting: a 5-year prospective study

AIM To evaluate the long-term stability of peri-implant bone formation following implant placement without grafting into resorbed posterior maxillae. MATERIALS AND METHODS Twenty-five implants of 10 mm were placed in 17 patients to rehabilitate atrophic maxillae by means of an osteotome sinus floor elevation (OSFE) procedure without grafting. Mean residual bone height was 5.4±2.3mm. Bone levels were evaluated at 1, 3 and 5 years using periapical radiographs. RESULTS All implants fulfilled survival criteria and gained peri-implant bone (mean increase 3.2±1.3mm). Implant protrusion into the sinus decreased from 4.9±1.9mm after surgery to 1.5±0.9mm after 5 years. Mean crestal bone loss amounting to 0.8±0.8mm stabilized over the 5-year observation interval. Twenty implants showed additional peri-implant bone gain following the 1-year control. CONCLUSIONS Implant rehabilitation of atrophic maxillae may be greatly simplified using implants 10mm and the OSFE technique without grafting. Grafting material is not needed to gain at least 3mm of bone in the atrophic maxilla. The procedure appears predictable with favourable long-term results.

Osteotome sinus floor elevation with and without grafting material in the severely atrophic maxilla. A 1-year prospective randomized controlled study

OBJECTIVES (1) To measure and compare endo-sinus bone levels around implants randomly placed with an osteotome sinus floor elevation (OSFE) procedure in grafted (control) and non-grafted (test) sinuses, (2) to evaluate the OSFE efficacy with short, tapered, and chemically modified hydrophilic surfaced implants in extremely atrophic maxillae, (3) to show that fused corticals may constitute a complication risk. MATERIAL AND METHODS The TE(®) SLActive 8 mm-long implants (Straumann AG) were placed using an OSFE procedure in 4 mm or less of bone height. Healing time before prosthetic rehabilitation was 10 weeks. One year after implant placement, bone levels were measured on standardized periapical radiographs. RESULTS Thirty-seven (17 tests, 20 controls) implants were placed in 12 patients with a mean maxillary residual bone height (RBH) of 2.4 ± 0.9 mm. Before loading, two control implants failed (RBH 1.4 and 1.2 mm); two others rotated at loading (one test, RBH 0.9 mm; one control, RBH 1.5 mm) but were uneventfully loaded after three additional months of healing. These adverse events and complications occurred when implants were placed in merged corticals. Endo-sinus bone gain was 3.9 ± 1.0 and 5.0 ± 1.3 mm for the test and control groups (P = 0.003). The 1-year success rate was 100% and 90%, respectively (P = 0.49). CONCLUSION Although more bone is gained when grafting material is used, this may not be required to promote endo-sinus bone gain. The OSFE procedure with or without grafting material could be efficient when the RBH is ≤ 4 mm. However, when both corticals merged, the risk of complication could increase.

Titanium hydride and hydrogen concentration in acid-etched commercially pure titanium and titanium alloy implants: a comparative analysis of five implant systems.

OBJECTIVES Acid etching is a popular method to texture the surface of dental implants. During etching, the titanium oxide protective layer is dissolved and small native hydrogen ions diffuse into the unprotected implant surface. They enrich the implant surface with hydrogen and precipitate into titanium hydride (TiH). The aim of this study was to measure the concentration of TiH at the implant surface and the total concentration of Hydrogen at five commercially available implant systems, made of either commercially pure (cp) titanium or titanium alloy. MATERIAL AND METHODS X-Ray diffraction (XRD) was conducted on each implant system to determine the compounds present at the implant surface. Following a TiH(2)/Ti calibration curve, the concentration of TiH was determined. Concentration of hydrogen in the implants was measured by the inert gas fusion thermal conductivity/infrared detection method. RESULTS XRD data showed that TiH was present on all cp titanium implants but not on the alloyed implants. TiH concentration varied between 5% and 37%. Hydrogen concentration varied between 43 and 108 ppm, no difference in uptake was found between the cp titanium and alloyed implants. Low solubility of hydrogen in alpha-titanium is responsible for precipitation into TiH. Stronger etching conditions led to higher concentration of TiH2-x. CONCLUSION High solubility of hydrogen in the beta-phase of the alloy is preventing hydrogen from precipitating into TiH. All implants, even those lacking TiH at the surface, were enriched with hydrogen. In all implants, hydrogen concentration was within the normative limit of 130 ppm.

Short Implants Placed with or without Grafting in Atrophic Sinuses: The 3‐Year Results of a Prospective Randomized Controlled Study

BACKGROUND The question whether a minimal maxillary residual bone height (RBH) allows the predictable use of osteotome sinus floor elevation (OSFE) remains unresolved. PURPOSE To evaluate the efficacy of short implants placed with OSFE in an RBH of ≤4 mm and to compare bone levels around implants placed with (control) or without (test) grafting after 3 years. MATERIALS AND METHODS Eight-millimeter implants were placed by OSFE in sinuses randomized to receive anorganic bovine bone or no grafting material. Healing time before prosthetic rehabilitation was 10 weeks. Peri-implant bone levels were measured on standardized periapical radiographs. RESULTS Thirty-seven implants (17 test, 20 control) were placed at a mean RBH of 2.4 ± 0.9 mm. Three implants failed during the 3-year follow-up. After 3 years, all implants had gained endosinus bone (test: 4.1 ± 1.0 mm; control: 5.1 ± 1.2 mm; p = .001). Mean bone gain was stable between 1 and 3 years in both groups. CONCLUSIONS Grafting is unnecessary to achieve bone augmentation of 4.1 mm; however, more bone is gained with grafting. Bone gained over 1 year was retained. Atrophic posterior maxillae can be predictably rehabilitated using OSFE and simultaneous placement of 8-mm implants.Background The question whether a minimal maxillary residual bone height (RBH) allows the predictable use of osteotome sinus floor elevation (OSFE) remains unresolved. Purpose To evaluate the efficacy of short implants placed with OSFE in an RBH of ≤4 mm and to compare bone levels around implants placed with (control) or without (test) grafting after 3 years. Materials and Methods Eight-millimeter implants were placed by OSFE in sinuses randomized to receive anorganic bovine bone or no grafting material. Healing time before prosthetic rehabilitation was 10 weeks. Peri-implant bone levels were measured on standardized periapical radiographs. Results Thirty-seven implants (17 test, 20 control) were placed at a mean RBH of 2.4 ± 0.9 mm. Three implants failed during the 3-year follow-up. After 3 years, all implants had gained endosinus bone (test: 4.1 ± 1.0 mm; control: 5.1 ± 1.2 mm; p = .001). Mean bone gain was stable between 1 and 3 years in both groups. Conclusions Grafting is unnecessary to achieve bone augmentation of 4.1 mm; however, more bone is gained with grafting. Bone gained over 1 year was retained. Atrophic posterior maxillae can be predictably rehabilitated using OSFE and simultaneous placement of 8-mm implants.

Accuracy of vertical height measurements on direct digital panoramic radiographs using posterior mandibular implants and metal balls as reference objects

OBJECTIVES Conventional panoramic radiography, a widely used radiographic examination tool in implant treatment planning, allows evaluation of the available bone height before inserting posterior mandibular implants. Image distortion and vertical magnification due to projection geometry is well described for rotational panoramic radiographs. To assess the accuracy of vertical height measurements on direct digital panoramic radiographs, implants and metal balls positioned in the posterior mandible were used as radio-opaque reference objects. The reproducibility of the measuring method was assessed by the inter- and intraobserver agreements. METHODS Direct digital panoramic radiographs, performed using a Kodak 8000C (Eastman Kodak Company, Rochester, NY), of 17 partially edentulous patients (10 females, 7 males, mean age 65 years) were selected from an X-ray database gathered during routine clinical evaluation of implant sites. Proprietary software and a mouse-driven calliper were used to measure the radiological length of 25 implants and 18 metal reference balls, positioned in mandibular posterior segments. The distortion ratio (DR) was calculated by dividing the radiological implant length by the implants real length and the radiological ball height by the balls real height. RESULTS Mean vertical DR was 0.99 for implants and 0.97 for balls, and was unrelated to mandibular sites, side, age, gender or observer. Inter- and intraobserver agreements were acceptable for both reference objects. CONCLUSIONS Vertical measurements had acceptable accuracy and reproducibility when a software-based calibrated measurement tool was used, confirming that digital panoramic radiography can be reliably utilized to determine the pre-operative implant length in premolar and molar mandibular segments.

Osteotome Sinus Floor Elevation Technique Without Grafting Material and Immediate Implant Placement in Atrophic Posterior Maxilla: Report of 2 Cases

PURPOSE This case report discusses 2 patients who required implant placement in the atrophic posterior maxilla to support a fixed prosthesis with the least invasive and shortest procedure. MATERIALS AND METHODS The reference standard of care would be to perform sinus augmentation with an autologous bone graft through the lateral approach with delayed implant placement. However, in these cases, the posterior maxillas were treated with an osteotome sinus floor elevation procedure without grafting material and simultaneous placement of short, 8- and 10-mm-long, tapered implants. RESULTS All implants achieved primary stability and were successfully loaded after 3.6 months of healing. At the 1- and 2-year follow-up visits, they were clinically stable and the final prostheses were functioning. The mean endosinus bone gain was 5.1 +/- 1.3 mm. In 1 of the patients, the implants were completely embedded in the newly formed bone and the sinus floor had been relocated apical to its previous demarcation. CONCLUSIONS The findings from these 2 cases suggest that the osteotome sinus floor elevation procedure without grafting material, and immediate placement of tapered implants, might be applied in situations for which previously only the lateral approach was considered (at the condition that implants achieve firm primary stability). More patients and longer follow-up are warranted to investigate how reliable this technique can be when applied to the atrophic maxilla.

Osteotome Sinus Floor Elevation without Grafting: A 10-Year Prospective Study

BACKGROUND Little is known about the long-term outcome of implants placed in the atrophic maxilla using osteotome sinus floor elevation (OSFE) without grafting. PURPOSE The study aims to evaluate the long-term efficiency of the procedure and stability of the peri-implant bone formed following implant placement without grafting into resorbed posterior maxilla. MATERIALS AND METHODS Twenty-five implants (≤10 mm in length) were placed in 17 patients using OSFE without grafting. The mean residual bone height was 5.4 ± 2.3 mm. Bone levels were evaluated at 1, 3, 5, and 10 years using periapical radiographs. RESULTS Fifteen patients (23 implants) participated in the 10-year examination. All implants fulfilled the survival criteria. Following surgery, the implant sites gained endo-sinus bone (mean: 3.0 ± 1.4 mm). The mean crestal bone loss (CBL) was limited to 1.0 ± 0.9 mm. The difference in mean endo-sinus bone gain and CBL was statistically significant between 1 and 10 years, but not between 3 and 5, 3 and 10, and 5 and 10 years. CONCLUSIONS At 10 years, the implant survival rate was 100%. Endo-sinus bone was mainly gained during the first year. This study demonstrates the long-term predictability of OSFE without grafting and simultaneous implant placement.

A 5‐ to 6‐year radiological evaluation of titanium plasma sprayed/sandblasted and acid‐etched implants: results from private practice

OBJECTIVES This study aimed to determine bone level changes after 5-6 years of follow-up for a large group of one-stage dental implants consecutively placed in private practice. Potential confounding factors influencing crestal bone loss (CBL) were also assessed. MATERIALS AND METHODS A total of 378 transmucosal Straumann implants in 174 patients were examined radiographically. Half of the study population (189 implants) had a titanium plasma sprayed (TPS) surface, and the other half (189 implants) were sandblasted and acid-etched (SLA). Mean CBL was measured from 5 to 6 years post-operative radiographs on the basis of known implant landmarks. Correlations of increased CBL with various independent variables were also investigated. Statistical analyses were performed using generalized estimating equations. RESULTS Radiographic measurements showed a CBL ≤ 1.5 mm for 65% of studied implants. A CBL > 1.5 mm was found for 28% of implants, while 7% of implants had a CBL ≥ 3 mm. Three factors significantly influenced CBL (P < 0.05): implant surface texture (TPS > SLA), smoking status (smokers > non-smokers), and implant location (anterior > posterior). CONCLUSIONS CBL was ≤1.5 mm after 5-6 years for the majority of followed implants. For implants with a CBL > 1.5 mm, statistically significant correlations were found for TPS surface type, anterior jaw locations, and smoking. Implant length did not influence CBL.

Paradigm Shift in the Management of the Atrophic Posterior Maxilla

When the posterior maxilla is atrophic, the reference standard of care would be to perform sinus augmentation with an autologous bone graft through the lateral approach and delayed implant placement. However, placement of short implants with the osteotome sinus floor elevation technique and without graft can be proposed for an efficient treatment of clinical cases with a maxillary residual bone height of 4 to 8 mm. The use of grafting material is recommended only when the residual bone height is ≤4 mm. Indications of the lateral sinus floor elevation are limited to cases with a residual bone height ≤ 2 mm and fused corticals, uncompleted healing of the edentulous site, and absence of flat cortical bone crest or when the patient wishes to wear a removable prosthesis during the healing period. The presented case report illustrates osteotome sinus floor elevation with and without grafting and simultaneous implant placement in extreme conditions: atrophic maxilla, short implant placement, reduced healing time, and single crown rehabilitation. After 6 years, all placed implants were functional with an endosinus bone gain.