Group 2 ITI Consensus Report: Prosthodontics and implant dentistry.

OBJECTIVES: Working Group 2 was convened to address topics relevant to prosthodontics and dental implants. Systematic reviews were developed according to focused questions addressing (a) the number of implants required to support fixed full-arch restorations, (b) the influence of intentionally tilted implants compared to axial positioned implants when supporting fixed dental prostheses (FDPs), (c) implant placement and loading protocols, (d) zirconia dental implants, (e) zirconia and metal ceramic implant supported single crowns and (f) zirconia and metal ceramic implant supported FDPs. MATERIALS AND METHODS: Group 2 considered and discussed information gathered in six systematic reviews. Group participants discussed statements developed by the authors and developed consensus. The group developed and found consensus for clinical recommendations based on both the statements and the experience of the group. The consensus statements and clinical recommendations were presented to the plenary (gathering of all conference attendees) and discussed. Final versions were developed after consensus was reached. RESULTS: A total of 27 consensus statements were developed from the systematic reviews. Additionally, the group developed 24 clinical recommendations based on the combined expertise of the participants and the developed consensus statements. CONCLUSIONS: The literature supports the use of various implant numbers to support full-arch fixed prostheses. The use of intentionally tilted dental implants is indicated when appropriate conditions exist. Implant placement and loading protocols should be considered together when planning and treating patients. One-piece zirconia dental implants can be recommended when appropriate clinical conditions exist although two-piece zirconia implants should be used with caution as a result of insufficient data. Clinical performance of zirconia and metal ceramic single implant supported crowns is similar and each demonstrates significant, though different, complications. Zirconia ceramic FDPs are less reliable than metal ceramic. Implant supported monolithic zirconia prostheses may be a future option with more supporting evidence.

Expression of transforming growth factor beta 1-related signaling proteins in irradiated vessels.

AIM: Microvascular free tissue transfer is a standard method in head and neck reconstructive surgery. However, previous radiotherapy of the operative region is associated with an increased incidence in postoperative flap-related complications and complete flap loss. As transforming growth factor beta (TGF-ß) 1 and galectin-3 are well known markers in the context of fibrosis and lectin-like oxidized low-density lipoprotein 1 (LOX-1) supports vascular atherosclerosis, the aim of this study was to evaluate the expression of TGF-ß1 and related markers as well as LOX-1 in irradiated vessels. MATERIALS AND METHODS: To evaluate the expression of galectin-3, Smad 2/3, TGF-ß1, and LOX-1, 20 irradiated and 20 nonirradiated arterial vessels were used for immunohistochemical staining. We semiquantitatively assessed the ratio of stained cells/total number of cells (labeling index). RESULTS: Expression of galectin-3, Smad 2/3, and TGF-ß1 was significantly increased in previously irradiated vessels compared with nonirradiated controls. Furthermore, LOX-1 was expressed significantly higher in irradiated compared with nonirradiated vessels. CONCLUSION: Fibrosis-related proteins like galectin-3, Smad 2/3, and TGF-ß1 are upregulated after radiotherapy and support histopathological changes leading to vasculopathy of the irradiated vessels. Furthermore, postoperative complications in irradiated patients can be explained by increased endothelial dysfunction caused by LOX-1 in previously irradiated patients. Consequently, not only TGF-ß1 but also galectin-3 inhibitors may decrease complications after microsurgical tissue transfer.

Esthetics and psyche-part 1: assessment of the influence of patients' perceptions of body image and body experience on selection of existing natural tooth color.

PURPOSE: The aim of this research was to test the hypothesis that patients' attitudes toward their body affect their capacity to accurately select their existing natural tooth color. MATERIALS AND METHODS: Standard validated psychologic assessments were used to determine a person's perception of body image and experience. Oral images were compared with the patients' perceptions of their natural tooth color, which were then compared with the actual tooth color judged by a dental professional. RESULTS: For the vital body dynamic and disliking body experience subscales, women exhibited a significantly more negative attitude toward their bodies than men (P = .000). Patients with a negative attitude toward their body tended to choose a lighter tooth color. The correlation between patients' and the testing physician's choices of color was r = 0.540 for women and r = 0.746 for men. CONCLUSIONS: Unhappiness with body image and experience results in poor perception of a patient's own oral image, which in turn results in a patient perceiving that his or her natural tooth color is lighter than that judged by a dental professional. This has clinical implications when trying to achieve patient satisfaction with dental prostheses.

Regenerative treatment of peri-implantitis bone defects with a combination of autologous bone and a demineralized xenogenic bone graft: a series of 36 defects.

AIM: As the treatment of peri-implantitis-induced bone loss is still a problem, we studied the regenerative treatment of these defects with a mix of autologous bone and a new type of bone graft substitute (demineralized xenogenic bone graft) including growth factors. MATERIAL AND METHODS: In a prospective manner, 36 cases of peri-implantitis-induced bone loss (depth >4 mm) in 22 patients were followed for 1 year. After resolving the acute infection by local rinsing, granulation tissue was removed. The implants were decontaminated with etching gel and the defects were filled with autologous bone mixed 1:1 with a xenogenic bone graft. The prosthetic reconstructions did not have to be removed. Values of probing depths as well as bone defects were analyzed. RESULTS: The radiologic evaluation of the bone defects after regenerative treatment revealed a mean reduction of 3.5 mm comparing the values from 5.1 mm prior to surgery to 1.6 mm 1 year after treatment. Average reduction of the probing depth was 4 mm. The remaining bone defects were larger than 3 mm in 4 out of 36 implants 1 year after treatment. Probing depths of more than 4 mm were present in seven implants. CONCLUSION: Within the limits of the study, we conclude that for bone defects larger than 4 mm in case of peri-implantitis, this single surgical intervention provided a reliable method to reduce bone defects.

Prosthetic screw detorque values in implants retained as cast bar superstructures or bars modified by the Cresco Ti Precision technique--a comparative in vivo study.

PURPOSE: This prospective clinical trial investigated the effect of different fabrication techniques on screw-joint stability in implant-retained frameworks. MATERIALS AND METHODS: Seventy-nine dental implants (39 Brånemark System and 40 Straumann) were inserted into 20 patients with an edentulous mandible. One of two fabrication techniques was randomly chosen as a definitive restoration, either a cast bar or a bar superstructure modified with the Cresco Ti Precision (CTiP) technique. The patients were divided into four groups depending on the type of implant and prosthetic superstructure: Straumann-conventional (Sc), Straumann-Cresco (SCr), Brånemark-conventional (Bc), and Brånemark-Cresco (BCr). Initial torque values and removal torque values were recorded with a custom-made digital torque controller both 1 week (T1) and 3 months (T2) after clinical function. RESULTS: Statistical analysis revealed significant differences in absolute detorque values at T1 (P = .002) with 4.51 Ncm (SD = 3.80) for the Sc group, 10.65 Ncm (SD = 4.42) for SCr, 11.24 Ncm (SD = 4.00) for Bc, and 9.02 Ncm (SD = 3.81) for BCr. At T2 (P = .000) the median values of lost torque were 5.08 Ncm (SD = 4.05) for the Sc group, 10.51 (SD = 3.00) for SCr, 7.50 (SD = 5.86) for Bc, and 9.41 Ncm (SD = 4.54) for BCr. However, when correlation of detorque values to initial torque values was performed, no statistical differences were found between groups or time points. The percentage of lost torque at T1 (P = .849) and T2 (P = .058) was 28.60% (SD = 21.80) and 32.85% (SD = 24.65), 30.04% (SD = 12.49) and 30.80% (SD = 8.66), 32.11% (SD = 11.37) and 21.03% (SD = 16.53), and 25.33% (SD = 10.69) and 27.83% (SD = 12.57) for the Sc, SCr, Bc, and BCr groups, respectively. CONCLUSIONS: The screw-joint stability of passivated bars is not superior to cast superstructures. A general decrease of approximately 30% of initial torque values can be expected in clinical situations, independent of the implant system used.

Three-dimensional analysis of changes of the malar-midfacial region after LeFort I osteotomy and maxillary advancement.

AIM: It has been the objective of the present prospective study to assess visible volume changes of the facial soft tissue after LeFort I osteotomy with advancement and to determine the soft-tissue-to-hard-tissue ratios of advancement. PATIENTS AND METHODS: Twenty adult patients (ten female, ten male, mean age 33.9 +/- 14.9 years) received a LeFort I osteotomy with advancement because of a maxillary protrusion. Lateral skull radiographs and optical three-dimensional (3D) scans of the facial surface were assessed preoperatively and 12 months after surgery. The lateral skull radiographs were used to carry out standard linear and angular cephalometric measurements. The pre- and postoperative optical 3D surface scans were registered. A well-defined area in the malar region was used to determine the visible volume changes for each side separately. The mean accommodation vector that transforms the preoperative into the postoperative surface was assessed for each facial half separately. The soft-tissue-to-hard-tissue ratios between the incision superius and the labrale superius, the maximal parasagittal advancement of soft tissue, and the accommodation vectors were calculated. RESULTS: A mean advancement of the incision superius of 5.3 +/- 2.1 mm was accompanied by a volume increase of 5.2 +/- 4.1 cm(3) in the right malar-midfacial region and 4.6 +/- 4.7 cm(3) on the left side, respectively, revealing a symmetrical volume change (p = 0.370). The soft-tissue-to-hard-tissue ratios were 80 +/- 94% for labrale superius and incision superius, 56 +/- 79% (right) and 51 +/- 56% (left) for accommodation vector and incision superius and 97 +/- 79% (right) and 98 +/- 89% (left) for maximal parasagittal advancement of soft tissue and incision superius. DISCUSSION: The determination of volume changes and accompanying accommodation vectors complete the cephalometric analysis during the follow-up of patients undergoing LeFort I osteotomy. The data show that maxillary advancement leads to a more pronounced shifting of the soft tissues in the malar-midfacial area than of the upper lip. The new parameters will help to assess normative soft tissue data based on 3D imaging with a view to an improved three-dimensional prediction of the operative outcome of orthognathic surgery away from the midline.

Comparative clinical results after implant placement in the posterior maxilla with and without sinus augmentation.

PURPOSE: The objective was to compare implants in the posterior maxilla with or without sinus floor augmentation. MATERIALS AND METHODS: A retrospective study was conducted of patients who received implants in the posterior maxilla. All patients received solitary, implant-retained fixed partial dentures or crowns. A standardized form for implant treatment was used to document the follow-up examination. The different parameters were initially analyzed descriptively by frequency distribution, measure of central tendency, and statistical spread. A 95% level of significance was set for all tests. RESULTS: A total of 76 patients with 141 dental implants in the posterior region of the maxilla were evaluated. Fifty-one patients with 71 implants received prior no augmentation (sinus floor elevation) and composed the control group. Twenty-five patients with 70 implants received an additional bone transfer prior to implant placement. The mean age of the patients at time of the follow-up examination was 49.7 years in the overall group, 52.6 years for men and 46.7 years for women. The implants inserted in an augmented area had similar implant stability and implant loss results after a mean functional observation period of 1.6 years (range, 0.5 to 4.7 years) compared to those inserted without augmentation. Augmented implants exhibited less peri-implant bone resorption. CONCLUSIONS: The outcomes for implants with augmentation were similar to those without augmentation.

Comparing bar and double-crown attachments in implant-retained prosthetic reconstruction: a follow-up investigation.

OBJECTIVES: A removable implant-retained dental prosthesis in an edentulous mandible can use telescopic crowns or a bar superstructure as anchorage elements for an overdenture. The aim of this study was to compare the clinical results for bar-anchored and telescopic crown-retained overdentures in implant prosthetic treatment of the toothless lower jaw with two or more implants placed in the intraforaminal region. MATERIAL AND METHODS: A clinical and radiographical comparison was made of the telescope vs. the bar method for removable prosthetic rehabilitation treatments in patients with an edentulous mandible. For evaluation of the clinical data, the sulcus fluid flow rate, Periotest values, and the peri-implant bone loss were recorded. RESULTS: In the follow-up examinations, 19 implant losses were reported between insertion and review of 328 implants. The frequency distribution of the observed loss rates showed no treatment-specific trend. In the group with bar-treated implants, failure led to 'group loss' of the whole prosthetic superstructure. Failure of one of the double-crown-stabilized full dental prosthesis could usually be adapted so that the overdenture remained usable even without re-implantation. CONCLUSIONS: After comparing all the clinical parameters evaluated, no significant difference between the stabilization of full dentures via conus and telescopic crowns and bar-anchored dentures could be found. The choice of one particular method remains the decision of the professional treating the patient.

Use of telemedicine for pre-implant dental assessment - a comparative study.

We evaluated real-time telemedicine for exchanging expert opinions in the area of pre-implant dental assessment. From 2003 to 2005, every tenth patient at the armed forces' dental clinic in Cologne-Wahn seeking implant counselling was discussed via videoconference (intervention group, n = 85). Indications, prosthodontic options, the required number of implants and implant positions were determined. The mean time required for the videoconferences was 3.5 min (range 1.0-9.5). In the control group (n = 772), the implant consultation was performed based on existing records, without using telemedicine. In three cases (3%), a basic change in the prosthodontic concept was required as compared to the telemedicine plan; in the control group, the concept changed in 7% of cases. The changes in the number and position of implants during therapy were also similar in the two groups. The results showed that telemedicine permitted satisfactory preoperative evaluation of the implantation operation.

Comparative study on interactive computer-aided-learning and computer-aided-testing in patient-based dental training in maxillofacial surgery.

AIM: The objective of this comparative study was to validate, through empirical data, the use of interactive, problem-oriented computer-aided-learning (CAL) and computer-aided-testing (CAT) in dental studies by directly comparing these methods with conventional teaching. METHOD: A total of 95 students from the third and fourth clinical semesters participated in an interdisciplinary seminar on oral maxillofacial implantology; 47 of these were taught using conventional teaching methods, while the remaining 48 students were taught using mobiTED, a CAL/CAT-based interactive communication system that can be used patient- and problem-oriented. An examination was given at the end of the course to evaluate student learning. A student's interest/attentiveness, involvement, knowledge gain, and the course attractiveness and quality were evaluated with visual analogue scales (VAS) in a subjective experience protocol. RESULTS: The study group taught using the CAL/CAT-based interactive communication system showed statistically significant better results in the examination, with a median score of 89.2%, while the conventional teaching study group achieved a median score of 76.0%. A VAS-based analysis of subjective experiences also revealed statistically significant differences between the two study groups. CONCLUSION: Use of the CAL/CAT system for interactive, problem-oriented learning in patient-based dental training led to increased levels of attentiveness, of student acceptance and of the perceived attractiveness of the seminar. CAL/CAT-mediated instruction also led to increased communication, with a subsequent improvement in the qualitative and quantitative parameters of knowledge transfer and cognitive knowledge assimilation. Use of CAL/CAT also facilitated the acquisition, appraisal, and understanding of complex medical data.

Clinical study on the correlation between psychogenic dental prosthesis incompatibility, oral stereognosis, and the psychologic diagnostic tools SCL-90-R and CES-D.

PURPOSE: The objective of this study was to use an oral stereognosis test to evaluate possible intraoral/sensorimotor causes in patients with a psychologic diagnosis of psychogenic prosthesis incompatibility, and to evaluate possible correlations between oral stereognosis and the psychologic diagnostic tools Symptom Checklist-90-R (SCL-90-R) and Center of Epidemiological Studies Depression Scale (CES-D). MATERIALS AND METHODS: The study cohort comprised 83 patients with complete dentures fabricated according to a standardized protocol. Twelve patients diagnosed with psychogenic prosthesis incompatibility (11 women, 1 man) using the SCL-90-R and CES-D scales in a previous study and a group of 24 randomly selected control subjects (14 women, 10 men) underwent an oral stereognosis test with 10 neutral-tasting plastic test specimens with a maximum edge length of 8 mm in 2 test cycles. RESULTS: The results revealed no significant differences in oral stereognostic ability between patients with diagnosed psychogenic dental prosthesis incompatibility and the control patients. The patients in the test group expressed clear dissatisfaction with their dentures. No correlation was found between oral stereognostic ability and the SCL-90-R or CES-D values. CONCLUSIONS: This study is the first to use oral stereognosis tests for patients with psychologically diagnosed psychogenic dental prosthesis incompatibility. The diagnosis of psychogenic prosthesis incompatibility by the SCL-90-R and CES-D scales is affirmed by the lack of correlations between the functional/anatomic aspects of oral stereognostic ability, psychologic diagnostic tools, and the clinical picture of psychogenic prosthesis incompatibility. Thus, psychogenic prosthesis incompatibility can be classified more explicitly as a psychosomatic disorder.

Dynamic periosteal elevation.

The osteoinductive potential of the periosteum can be stimulated by raising the periosteum using a type of distraction. This was tested and confirmed in an animal experiment in 6 Goettingen minipigs. A titanium mesh was implanted beneath the periosteum and then raised. Bone formed underneath the mesh, with rows of micro-pillars similar to those found after osteodistraction. The main advantages of dynamic periosteal elevation are that invasion and morbidity are minimal. Clinically it might be applicable in craniomaxillofacial surgery, in augmentation before implantation, and in reconstruction of the skull.

Neurophysiologic and long-term effects of clinical hypnosis in oral and maxillofacial treatment--a comparative interdisciplinary clinical study.

This prospective comparative clinical study evaluated the effectiveness of clinical hypnosis and its long-term effect in oral and maxillofacial treatment. A total of 45 highly anxious and nonanxious subjects were evaluated by subjective experience and objective parameters. Parameters were EEG, ECG, heart rate, blood pressure, blood oxygen saturation, respiration rate, salivary cortisol concentration, and body temperature. During and subsequent to the operative treatment, hypnosis led to a significant reduction of systolic blood pressure, and respiration rate and to significant changes in the EEG. The subjective values of the parameters evaluated existing anxiety mechanisms and patterns and possible strategies to control them, whereas the objective parameters proved the effectiveness of hypnosis and its long-term effect.

Rapid induction of hypnosis by finger elongation: a brief communication.

This clinical pilot study on finger elongation for induction of hypnosis attempts to determine whether the observed response is a hypnotic phenomenon or a simple physiologic reaction. Sixteen volunteers participated in the 5-phase study, which measured relative and absolute changes in the length of each finger prior to and after each phase. A distinctive elongation was statistically significant for the hypnosis condition. In addition, findings suggest changes in the metacarpus. Further investigation is indicated to shed light on this apparent phenomenon.

Different substitute biomaterials as potential scaffolds in tissue engineering.

PURPOSE: To find the optimal scaffold for tissue-engineered bone, one approach is to test existing biomaterials on their suitability as scaffolds. In this study, the suitability of different alloplastic and xenogenic biomaterials as scaffolds for ex vivo osteoblast cultivation was investigated. MATERIALS AND METHODS: Normal human osteoblast cells were cultured on the surface of bovine collagenous materials, bovine hydroxyapatite, porcine gelatin, synthetic polymer, and collagen-containing bovine hydroxyapatite, and the investigation of proliferation was performed after 24, 72, and 120 hours. Measurement of the differentiation marker alkaline phosphatase and osteocalcin was made after 20 days of incubation. RESULTS: The obtained data showed significantly higher proliferation and differentiation rates in cells cultivated on collagen-rich biomaterials in comparison to noncollagenous or collagen-poor biomaterials (P < .05). DISCUSSION: In tissue engineering the scaffold should be biocompatible and serve as a proper matrix for the cells to produce the new structural environment of extracellular matrix ex vivo. Collagen supports initial cell attachment and cell proliferation, allowing immature osteogenic cells to differentiate into mature osteoblasts, but collagen may not be the only dominating factor for cell-matrix interaction during ex vivo bone formation. CONCLUSION: These data suggest that a 3-dimensional collagen matrix can provide a more favorable environment for the attachment, proliferation, and differentiation of in vitro osteoblastlike cells, at least until the initial stage of differentiation, than noncollagenous biomaterials.

The bone-metal interface of defect and press-fit ingrowth of microwave plasma-chemical vapor deposition implants in the rabbit model.

PURPOSE: The histological differences between the defect and contact areas of the implant surface to bone were tested in 35 New Zealand White rabbits in a standardized model. Microwave plasma chemical vapor-coated implant probes were tested in control and uncoated materials. MATERIAL AND METHODS: In each femur of 35 rabbits, cylindrical implant rods with a planed side were inserted. Three groups, divided in coated and uncoated material at half, were observed 42, 84 and 168 days. The probes were examined histologically for bone-implant contact in the curved and plane (defect area) sides. RESULTS: Generally the bone-implant contact seems to be nearly constant in time in the curved area of coated and uncoated probes. Here the implant was inserted in the press-fit mode. Diamond-coated probes showed similar bone-implant contact (51.9% (42 days), 62.5% (84 days), 56.1% (168 days)) compared to uncoated material (56.2%, 65.4%, 62.9%). The defect area (plane side) had no bone-implant contact at the time of insertion and showed increasing values on longer observation times with only significant differences in the 42-day group between coated (17.85%, 35.2%, 47.7%) and uncoated materials (35.5%, 40.55%, 51.81%). CONCLUSION: The evaluation of the curved side of the implant probe showed no great variation of bone-implant contact within the described observation times. This model simulates the usual implant insertion situation. The diamond-coated material becomes osseointegrated at a later time point. The bone-implant contact was only statistically relevant in one group in comparison to uncoated material.

Sensor-based laser ablation for tissue specific cutting: an experimental study.

The interaction of laser light and tissue causes measurable phenomenons. These phenomenons can be quantified and used to control the laser drilling within a feedback system. Ten halves of dissected minipig jaws were treated with an Er:YAG laser system controlled via a feedback system. Sensor outputs were recorded and analyzed while osteotomy was done. The relative depth of laser ablation was calculated by 3D computed tomography and evaluated histologically. The detected signals caused by the laser-tissue interaction changed their character in a dramatic way after passing the cortical bone layer. The radiological evaluation of 98 laser-ablated holes in the ten halves showed no deeper ablation beyond the cortical layer (mean values: 97.8%). Histologically, no physical damage to the alveolar nerve bundle was proved. The feedback system to control the laser drilling was working exactly for cortical ablation of the bone based on the evaluation of detected and quantified phenomenon related to the laser-tissue interaction.

Analysis of bone resorption after secondary alveolar cleft bone grafts before and after canine eruption in connection with orthodontic gap closure or prosthodontic treatment.

PURPOSE: We sought to analyze the success rate of secondary alveolar cleft bone grafts before and after canine eruption in connection with orthodontic gap closure or gap opening. PATIENTS AND METHODS: Sixty-eight secondary alveolar cleft bone grafts with iliac crest spongiosa were carried out in 57 patients (mean age, 9 years; age range, 8 to 11 years) with 11 bilateral and 46 unilateral clefts of the lip, alveolus, or palate. Gap closures were carried out after 53 bone grafts (78%), and gap openings with subsequent dental implants were carried out with 15 bone grafts (22%). The parameters acquired radiologically (orthopantomograms) at the time of the surgery and the follow-up examination (mean age, 3 years; age range, 7 months to 9 years) were 1) bone resorption in relation to the interdental height of the alveolar process in the vicinity of the cleft and 2) root growth of the teeth in the vicinity of the cleft. The statistically significant differences (P <.05) were monitored with a software program. Resorption grades I and II (>50% of the interalveolar bone height) were considered to be a success. RESULTS: Resorption was grade I in 69%, grade II in 19%, grade III in 10%, and grade IV in 1% of cases. Thus, the overall success rate was 88%. At the time of the osteoplasty, the root growth of the tooth in the immediate vicinity of the cleft was fully completed in 27 teeth (39%), three-quarters completed in 23 teeth (26.5%), and semicompleted in 18 teeth (33.8%). Twelve teeth (18%) in the vicinity of the cleft (lateral incisors/canine) remained unerupted and displaced after the surgery. It was necessary to expose unerupted teeth surgically to reposition them orthodontically. The resorption losses were significantly lower with gap closures than with gap openings (P <.001). However, bone grafts performed before canine eruption were largely carried out with the objective of orthodontic gap closure, in contrast to the bone grafts that were carried out after canine eruption (P <.02). CONCLUSION: Gap closures provide more favorable results than do gap openings in regard to resorption. Controlled dental eruptions or orthodontic gap closures reduce the graft resorption. The exact timing of surgery proved to be only a secondary consideration.

The endoscopically controlled osteotome sinus floor elevation: a preliminary prospective study.

PURPOSE: It was the aim of the present prospective study to quantify the gain in height of implant sites by endoscopically controlled osteotome sinus floor elevations (ECOSFE) with simultaneous implant placement and to report the number of sinus membrane perforations. MATERIALS AND METHODS: From October 1999 to December 2000, of 92 sinus floor elevations, 18 were carried out endoscopically controlled with an osteotome technique. As augmentation material, beta-tricalcium phosphate (beta-TCP) or autogenous bone was used; 22 implants were placed. RESULTS: The residual height of the alveolar crest in the posterior maxilla was 6.8 +/- 1.6 mm on average. The implant lengths ranged from 10 to 16 mm (mean implant length 12.2 +/- 1.4 mm). They were significantly larger than the residual height of the alveolar crests (P < .0005). Elevation of the sinus floor with an osteotome had to be supported by conventional sinus floor elevation instruments after a mean elevation of 3.0 +/- 0.8 mm to prevent perforation of the sinus membrane. However, 1 perforation occurred, which was repaired with a periosteal patch. At stage 2 surgery, 2 implants were removed because of mobility. Endoscopic control revealed one case in which beta-TCP could be found within the sinus; another case showed areas of polypoid mucosa on the sinus floor. DISCUSSION: With the ECOSFE, perforations of the sinus membrane can be visualized; however, they cannot be avoided. Although this technique is less invasive than the lateral window technique, it cannot be recommended as a standard procedure in the posterior maxilla because of the large amount of additional equipment needed and the technically demanding procedure. CONCLUSION: The use of the ECOSFE should be confined to scientific trials.