			Home About us Contact

Posterior Maxilla (posterior + maxilla)

Distribution by Scientific Domains

Medical Sciences	100%

Selected Abstracts

Accuracy of Linear Measurement Provided by Cone Beam Computed Tomography to Assess Bone Quantity in the Posterior Maxilla: A Human Cadaver Study

CLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 4 2008
Sophie Veyre-Goulet DDS
ABSTRACT Purpose: The aim of this study was to assess, for implant placement in the posterior maxilla, the accuracy of linear measurements provided by cone beam computed tomography (CBCT) using an image intensifier tube and television (TV) chain as an X-ray detector despite a loss of contrast resolution. The NewTom® 9000 (Quantitative Radiology, Verona, Italy) was used to explore the posterior maxilla. Materials and Methods: Fourteen measurements were taken in three dry maxillaries. On every anatomical site, three fiducial markers were placed on the bony crest to define a plane. Dry maxillaries were submitted to CBCT imaging examination. The maxillaries were then sawn according to the previously defined planes, and bone height and width were assessed using a caliper. The same measurements were taken on images. Results: Clinical analysis demonstrated no difference between real measurements and image measurements. Conclusions: Although cadaver bone density may not correspond to the density of vital bone, this in vitro study indicates that CBCT images provided by technique using image intensifier tube and TV chain as an X-ray detector are reliable to define the bone volume of the posterior maxilla for the purpose of planning the implant axis. [source]

Implants placed in combination with an internal sinus lift without graft material: an analysis of short-term failure

JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 2 2009
Olaf Gabbert
Abstract Aim: Investigation of the short-term survival of implants placed in combination with an internal sinus lift (ISL) without graft material. Material and Methods: Thirty-six patients received 92 screw-shaped dental implants in combination with an ISL. No bone grafts or bone substitutes were used. Forty-four patients with 77 implants in the native posterior maxilla served as controls. X-rays taken after implant placement and 6 months later were evaluated for the presence of bone gain at the apical aspect of the implants. Kaplan,Meier survival curves and Cox regression analysis were used to estimate survival curves and to isolate risk factors for implant failures. Results: Within a mean observation period of 1.2 years (minimum 9 months; maximum 3.7 years), four failures were recorded in the experimental group and two in the controls. The probability of survival was above 94% for both groups. Six,nine months after surgery, bone gain was observed in 29 out of 92 implants. Comparison of the experimental group and controls revealed no effect of ISL and membrane perforation on the probability of survival. Conclusions: Promising short-term outcomes were observed for implants with ISL without graft material; for a substantial proportion of implants, apical bone gain was observed in the first 6,9 months. [source]

Bone formation at recombinant human bone morphogenetic protein-2-coated titanium implants in the posterior maxilla (Type IV bone) in non-human primates

JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 11 2008
Ulf M. E. Wikesjö
Abstract Background: Studies using ectopic rodent and orthotopic canine models (Type II bone) have shown that titanium porous oxide (TPO) surface implants adsorbed with recombinant human bone morphogenetic protein-2 (rhBMP-2) induce local bone formation including osseointegration. The objective of this study was to evaluate local bone formation and osseointegration at such implants placed into Type IV bone. Material and Methods: rhBMP-2-coated implants were installed into the edentulated posterior maxilla in eight young adult Cynomolgus monkeys: four animals each received three TPO implants adsorbed with rhBMP-2 (2.0 mg/ml) and four animals each received three TPO implants adsorbed with rhBMP-2 (0.2 mg/ml). Contra-lateral jaw quadrants received three TPO implants without rhBMP-2 (control). Treatments were alternated between left and right jaw quadrants. Mucosal flaps were advanced and sutured to submerge the implants. The animals received fluorescent bone markers at weeks 2, 3, 4, and at week 16 when they were euthanized for histologic analysis. Results: Clinical healing was uneventful. Extensive local bone formation was observed in animals receiving implants adsorbed with rhBMP-2 (2.0 mg/ml). The newly formed bone exhibited a specific pinpoint bone,implant contact pattern regardless of rhBMP-2 concentration resulting in significant osseointegration; rhBMP-2 (2.0 mg/ml): 43% and rhBMP-2 (0.2 mg/ml): 37%. Control implants exhibited a thin layer of bone covering a relatively larger portion of the implant threads. Thus, TPO control implants bone exhibited significantly greater bone,implant contact (,75%; p<0.05). There were no statistically significant differences between rhBMP-2-coated and control implants relative to any other parameter including peri-implant and intra-thread bone density. Conclusion: rhBMP-2-coated TPO implants enhanced/accelerated local bone formation in Type IV bone in a dose-dependent fashion in non-human primates resulting in significant osseointegration. rhBMP-2-induced de novo bone formation did not reach the level of osseointegration observed in native resident bone within the 16-week interval. [source]

Recombinant human bone morphogenetic protein-7 in maxillary sinus floor elevation surgery in 3 patients compared to autogenous bone grafts

JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 9 2000
A clinical pilot study
Abstract Background/Aims: This pilot study was designed to determine the clinical bone formation ability of a human recombinant DNA bone morphogenetic protein-7, also referred to as Osteogenic Protein-1 [OP-1] combined with a collagen carrier, implanted in the maxillary sinus of 3 patients. The results were compared with a group of 3 patients treated with sinus floor elevation and autogenous bonegrafts. Methods: 6 consecutive patients, 4 female and 2 male, between 48 and 57 years of age were treated by means of sinus floor elevation for insufficient bone height in the posterior maxilla for implant surgery. 3 patients, 2 female and 1 male, were treated with OP-1 attached to a collagen device. In these patients, 4 maxillary sinus grafting procedures according to Tatum's method were carried out. 1 g of collagen carrier containing 2.5 mg rhOP-1 mixed with 3 ml of saline was placed between the bony floor and the elevated mucosal lining of the most caudal part of the maxillary sinus, in order to increase the vertical bone dimension to place dental implants of a sufficient length. The 3 other patients, also 2 female and 1 male, with a total of 5 sinus sites, were treated with sinus floor elevation and autogenous iliac crest bonegrafts. After 6 months, during dental implant preparation, bone cores were taken for histology. Thus, clinical, radiological and histological results of the 2 groups of 3 patients were compared. Results: 6 months after sinus grafting with OP-1, in 1 male, well-vascularized bonelike tissue of good quality was observed clinically. This could be confirmed by histology. In the second, female, patient no bone formation was observed at all. A cyst-like granular tissue mass, without purulent content, was removed. In the 3rd, female, patient, who received bilateral sinus grafts, some bonelike formation was seen, however it showed flexible tissue which led to the decision that at 6 months after the sinus grafting, the implant placement had to be postponed. In all 5 autogenous grafted sinuses a bone appearance similar to normal maxillary bone was observed clinically as well as histologically and dental implants could be placed six months after sinus floor elevation surgery. Conclusions: These findings indicate that the OP-1 device has the potential for initiating bone formation in the human maxillary sinus within 6 months after a sinus floor elevation operation. However, the various findings in these 3 patients indicate that the behaviour of the material is at this moment insufficiently predictable, in this indication area. Further investigation is indicated before OP-1 can be successfully used instead of the "gold standard" autogenous bone graft. [source]

Maxillary Sinus Elevation Surgery: An Overview

JOURNAL OF ESTHETIC AND RESTORATIVE DENTISTRY, Issue 5 2003
ELIAZ KAUFMAN DDS
ABSTRACT Maxillary sinus elevation surgery was developed to increase the height of bone available for implant placement in the posterior maxilla. The efficacy and predictability of this procedure have been determined in numerous studies. The basic approach to the sinus (Caldwell-Luc operation) involves an osteotomy performed on the lateral maxillary wall, elevation of the sinus membrane, and placement of bone graft material. The graft materials can be categorized into four groups: autogenous bone, allografts (harvested from human cadavers), alloplasts (synthetic materials), and xenografts (grafts from a nonhuman species). These graft materials can be used alone or in combination with each other. Implant placement can occur at the same surgical procedure (immediate placement) or following a healing period of 6 to 9 months (delayed placement). A more conservative approach to the sinus, the osteotome technique, has been described as well. CLINICAL SIGNIFICANCE This article provides an overview of the surgical technique, with emphasis on anatomic considerations, preoperative patient evaluation (clinical and radiographic), indications and contraindications to the procedure, and possible risks and complications. [source]

Anatomical study of the pyramidal process of the palatine bone in relation to implant placement in the posterior maxilla

JOURNAL OF ORAL REHABILITATION, Issue 2 2001
S. P. Lee
The placement of dental implants in the molar region of the maxilla is often difficult because of insufficient bone volume and the inferior bone quality. In order to avoid these limitations, the pillar of bone, which is composed of the maxillary tuberosity, the pyramidal process of the palatine bone and the pterygoid process of the sphenoid bone, was introduced for implant placement. In fact, the pyramidal process is the posterior structure where implants are placed but until now, there is no available data of the size or shape of the pyramidal process. Therefore, we measured the height, anteroposterior distance and mediolateral distance of the pyramidal process and observed the shape of lateral and posterior surfaces of the pyramidal process of 54 Korean edentulous dry skulls in this study. The height was 13·1 mm (male: 13·6 mm, female: 12·4 mm). The anteroposterior distance was 6·5 mm (male: 6·7 mm, female: 6·1 mm). The mediolateral distance was 9·5 mm (male: 9·9 mm, female: 9·0 mm). The most common type was the right-angled triangle in the lateral surface (44·4%) and in the posterior surface (66·7%). There was no statistical significance between the male and the female in all items (P > 0·05). These results provide anatomical features in relation to placement of dental implants in the molar region of the maxilla and would be useful in treatment planning of partially or completely edentulous patients. [source]

Early Loading after 21 Days of Healing of Nonsubmerged Titanium Implants with a Chemically Modified Sandblasted and Acid-Etched Surface: Two-Year Results of a Prospective Two-Center Study

CLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 1 2010
Dean Morton BDS
ABSTRACT Purpose: The aim of this two-center study was to evaluate screw-type titanium implants with a chemically modified, sandblasted and acid-etched surface when placed in the posterior maxilla or mandible, and loaded 21 days after placement. Material and Methods: All 56 patients met strict inclusion criteria and provided informed consent. Each patient displayed either a single-tooth gap, an extended edentulous space, or a distal extension situation in the posterior mandible or maxilla. Eighty-nine dental implants (SLActive®, Institut Straumann AG, Basel, Switzerland) were inserted according to an established nonsubmerged protocol and underwent undisturbed healing for a period of 21 days. Where appropriate, the implants were loaded after 21 days of healing with provisional restorations in full occlusion. Definitive metal ceramic restorations were fabricated and positioned on each implant after 6 months of healing. Clinical measurements regarding soft tissue parameters and radiographs were obtained at different time points up to 24 months after implant placement. Results: Of the 89 inserted implants, two (2.2%) implants failed to integrate and were removed during healing, and two (2.2%) additional implants required a prolonged healing time. A total of 85 (95.6%) implants were therefore loaded without incident after 21 days of healing. No additional implant was lost throughout the study period, whereas one implant was lost to follow-up and therefore left unaccounted for further analysis. The remaining 86 implants all exhibited favorable radiographic and clinical findings. Based on strict success criteria, these implants were considered successfully integrated 2 years after insertion, resulting in a 2-year success rate of 97.7%. Conclusion: The results of this prospective two-center study demonstrate that titanium implants with a modified SLA surface can predictably achieve successful tissue integration when loaded in full occlusion 21 days after placement. Integration could be maintained without incident for at least 2 years of follow-up. [source]

Minimally Invasive Antral Membrane Balloon Elevation , Results of a Multicenter Registry

CLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 2009
Efraim Kfir DMD
ABSTRACT Background and Purpose: Frequently, the posterior maxilla lacks sufficient bone mass to support dental implants. This multiphysician registry assessed the feasibility and safety of minimally invasive antral membrane balloon elevation (MIAMBE), followed by bone augmentation and implant fixation. Materials and Methods: One hundred twelve consecutive patients were referred for MIAMBE. Following pre-procedural assessment and informed consent, patients underwent alveolar crest exposure, and 3 mm osteotomy followed by MIAMBE. Platelet-rich fibrin and bone substitutes were injected under the antral membrane; implant placement and primary closure were executed at the same sitting. Implant loading was carried out 6 to 9 months later. Results: One hundred nine (97.3%) patients successfully concluded the initial procedure. Three patients had membrane tear requiring procedure abortion. One case of infection was documented at 4 weeks. Procedure time was 58 ± 23 minutes. Incremental bone height consistently exceeded 10 mm, and implant survival of 95% was observed at 6 to 9 months. Conclusion: MIAMBE can be applied to all patients in need of posterior maxilla bone augmentation with high procedural success, low complication rate, and satisfactory bone augmentation and implant survival. As it is minimally invasive and associated with minimal discomfort, MIAMBE should be an alternative to the currently employed methods of maxillary bone augmentation. [source]

Accuracy of Linear Measurement Provided by Cone Beam Computed Tomography to Assess Bone Quantity in the Posterior Maxilla: A Human Cadaver Study

Internal Sinus Manipulation (ISM) Procedure: A Technical Report

CLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 3 2007
Jason M. Yamada DDS
ABSTRACT Background, The sinus augmentation procedure has facilitated dental implant treatment in the posterior maxilla where there is insufficient bone for implant placement. A modified Caldwell-Luc, lateral window technique can be applied in most cases needing sinus augmentation in order to create a larger bone volume. However, treatment morbidity can be a concern, especially in the form of postoperative swelling due to surgical trauma. Vertical augmentation using osteotomes has also been selected as a choice of treatment due to less invasive surgery and less postoperative trauma. Although the osteotome technique enables the surgeon to raise the sinus membrane internally through an implant osteotomy site, the quantity and predictability of bone augmentation can be limiting due to the elasticity of the Schneiderian sinus membrane, difficulty of the membrane to separate from the floor as well as the inability to have direct tactile access to "peel" the membrane off of the floor. Purpose, The objective of this report is to present a new, minimally invasive sinus augmentation technique, called the Internal Sinus Manipulation (ISM) procedure, which has been developed to facilitate sinus floor augmentation while reducing treatment morbidity and yet have direct tactile access to raise the membrane off of the sinus floor. Surgical Technique, Access to the Schneiderian sinus membrane is achieved without perforation of the membrane through a conventional osteotomy drilling procedure alone or combined with osteotome technique, followed by reflection of the membrane utilizing special ISM instrumentation and bone graft procedure laterally and vertically through the osteotomy site. A planned implant is then placed. Conclusion, The Internal Sinus Manipulation procedure can be used as an alternative treatment modality for sinus augmentation as compared to the external lateral window technique while reducing postoperative morbidity for the patients who need implant treatment in posterior maxillary areas. [source]

Five-Year Survival Distributions of Short-Length (10 mm or less) Machined-Surfaced and Osseotite® Implants

CLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 1 2004
Sylvan Feldman DDS
ABSTRACT Background: In cases of reduced alveolar bone height, implants of short length (10 mm or less) may be employed although there is a perceived risk that because of their small stature they will be unable to tolerate occlusal loads and will fail to osseointegrate. Purpose: This report describes an analysis of prospective multicenter clinical studies evaluating the risk for failure of short-length implants, comparing dual acid-etched (DAE) Osseotite® implants (Implant Innovations, Inc., Palm Beach Gardens, FL, USA) to machined-surfaced implants. Materials and Methods: Admission criteria were the same for both data sets. Baseline variables of demographics including age, gender and smoking status, bone quality, location, implant dimensions, and types of prostheses were compared to ensure balance among groups. Cumulative survival rates (CSRs) were calculated with the Kaplan-Meier estimator. Results: The implant data included 2,294 implants for the DAE series and 2,597 implants for the machined-surfaced series. Patient demographics showed similar percentages of occurrence for all variables. The distributions of implants between short- and standard-length data sets for baseline variables including width, location, and restorative type were similar, qualifying these data sets for comparison of the independent variable of length. Overall, there was a 2.2% difference in 5-year CSRs between the machined-surfaced short- and the standard-length implants. For these implants a 7.1% difference was observed in the posterior maxilla and an 8.5% difference in the anterior maxilla. For DAE implants the overall difference between "standards" and "shorts" was 0.7%, which is not statistically significant. Conclusion: In this analysis the difference in CSRs between short- and standard-length implants was greater for machined-surfaced implants than for DAE implants. [source]

Clinical and Radiographic Evaluation of the 5-mm Diameter Regular-Platform Brånemark Fixture:2- to 5-Year Follow-up

CLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 1 2002
DSc Odont, Georges Tawil DDS
ABSTRACT Purpose: The purpose of this study was to report the clinical results obtained with 5-mm diameter regular-platform Brånemark implants after 2 to 5 years of follow-up. A secondary aim was to compare the clinical outcome to that of adjacently placed standard 3.75-mm fixtures in the same patients under the same operative condition and in the same prosthetic construction. Materials and Methods: Sixty patients, with a mean age of 54 years, received a total of 97 5-mm diameter regular-platform fixtures. The majority of the implants were placed at molar sites. In 41 of the patients, 53 5-mm diameter implants were placed adjacent to 62 standard 3.75-mm diameter fixtures in the same prosthetic reconstruction. All implants were submerged for an average period of 4 to 6 months. Abutment connection was done according to standard protocol. The prosthetic treatment consisted of freestanding fixed bridges. Results: The cumulative survival rate of the 5-mm diameter implants loaded for a period of 2 to 5 years was 96.9%. Only three implants failed. They were placed in type 4 bone in the posterior maxilla. Bone loss over the first year was 0.70 mm and over a 3-year period 0.81 mm. Implants placed in type 4 bone showed significantly higher bone loss. No difference in the resorption rate could be found between the maxillary and the mandibular implants or between the various implant lengths. There was no significant difference between the bone loss around the 5-mm diameter fixtures and the adjacent 3.75-mm diameter standard fixtures. Conclusion: The present study demonstrated a high predictability of 5-mm diameter regular-platform implants when placed in the posterior maxilla and mandible. [source]

Histological and histomorphometrical analyses of biopsies harvested 11 years after maxillary sinus floor augmentation with deproteinized bovine and autogenous bone

CLINICAL ORAL IMPLANTS RESEARCH, Issue 9 2010
Arne Mordenfeld
Abstract Objective: The purpose of the present study was to histologically and histomorphometrically evaluate the long-term tissue response to deproteinized bovine bone (DPBB) particles used in association with autogenous bone and to compare particle size after 6 months and 11 years, in the same patients, in order to determine possible resorption. Material and methods: Twenty consecutive patients (14 women and six men) with a mean age of 62 years (range 48,69 years) with severe atrophy of the posterior maxilla were included in this study. Thirty maxillary sinuses with <5 mm subantral alveolar bone were augmented with a mixture of 80% DPBB and 20% autogenous bone. Eleven years (mean 11.5 years) after augmentation, biopsies were taken from the grafted areas of the 11 patients who volunteered to participate in this new surgical intervention. The following histomorphometrical measurements were performed in these specimens: total bone area in percentage, total area of the DPBB, total area of marrow space, the degree of DPBB,bone contact (percentage of the total surface length for each particle), the length of all DPBB particles and the area of all DPBB particles. The length and the area of the particles were compared with samples harvested from the same patients at 6 months (nine samples) and pristine particles from the manufacturer. Results: The biopsies consisted of 44.7±16.9% lamellar bone, 38±16.9% marrow space and 17.3±13.2% DPBB. The degree of DPBB to bone contact was 61.5±34%. There were no statistically significant differences between the length and area of the particles after 11 years compared with those measured after 6 months in the same patients or to pristine particles from the manufacturer. Conclusion: DPBB particles were found to be well integrated in lamellar bone, after sinus floor augmentation in humans, showing no significant changes in particle size after 11 years. To cite this article: Mordenfeld A, Hallman M, Johansson CB, Albrektsson T. Histological and histomorphometrical analyses of biopsies harvested 11 years after maxillary sinus floor augmentation with deproteinized bovine and autogenous bone. Clin. Oral Impl. Res. 21, 2010; 961,970. doi: 10.1111/j.1600-0501.2010.01939.x [source]

Optimal microvessel density from composite graft of autogenous maxillary cortical bone and anorganic bovine bone in sinus augmentation: influence of clinical variables

CLINICAL ORAL IMPLANTS RESEARCH, Issue 2 2010
Pablo Galindo-Moreno
Abstract Objectives: The objectives of this study were to assess the microvessel density (MVD) of intra-sinus grafts after 6 months of wound healing and to study the relationship between revascularization processes and patient clinical variables and habits. Material and methods: We performed 45 maxillary sinus augmentations with different implant placements in 25 consecutive patients, obtaining bone cores of the grafted area for histological, histomorphometric and immunohistochemical study. Biopsies were also taken from pristine bone in the posterior maxilla (control). Results: All implants survived at 24 months. Biopsies of sinus augmentation areas showed significantly greater remodeling activity vs. pristine bone, with significantly more osteoid lines. The morphometry study revealed 34.88±15.2% vital bone, 32.02±15.1% non-mineralized tissue and 33.08±25.4% remnant anorganic bovine bone particles. The number of CD34-positive vessels was 86.28±55.52/mm2 in graft tissue vs. 31.52±13.69/mm2 in native tissue (P=0.002, Mann,Whitney U=46). The larger amount of non-mineralized tissue in grafts was directly correlated with a higher MVD (r=0.482, P=0.0001, Pearson's test). MVD was affected by the presence of periodontitis or tobacco and alcohol consumption. Conclusion: The angiogenesis and revascularization obtained by this type of graft achieve adequate tissue remodeling for osseointegration and are influenced by periodontal disease and tobacco or alcohol consumption. To cite this article: Galindo-Moreno P, Padial-Molina M, Fernández-Barbero JE, Mesa F, Rodríguez-Martínez D, O'Valle F. Optimal microvessel density from composite graft of autogenous maxillary cortical bone and anorganic bovine bone in sinus augmentation: influence of clinical variables. Clin. Oral Impl. Res. 21, 2010; 221,227 doi: 10.1111/j.1600-0501.2009.01827.x [source]

Maxillary sinus floor elevation using the (transalveolar) osteotome technique with or without grafting material.

CLINICAL ORAL IMPLANTS RESEARCH, Issue 7 2009
Part I: implant survival, patients' perception
Abstract Objectives: To analyze the survival and success rates of implants installed utilizing the (transalveolar) osteotome technique, to compare peri-implant soft tissue parameters and marginal bone levels of osteotome-installed implants with implants placed using standard surgical procedures, and to evaluate patient-centered outcomes. Material and methods: During 2000 to 2005, 252 Straumann® dental implants were inserted in 181 patients. The surgical technique was a modification of the original osteotome technique presented by Summers. In addition to the clinical examination, the patients were asked to give their perception of the surgical procedure, utilizing a visual analogue scale. Results: The cumulative survival rate of the osteotome-installed implants after a mean follow-up time of 3.2 years, was 97.4% (95% confidence intervals: 94.4,98.8%). From the 252 implants inserted, three were lost before loading and another three were lost in the first and second year. According to residual bone height the survival was 91.3% for implant sites with ,4 mm residual bone height, and 90% for sites with 4 mm and 5 mm, when compared with that of 100% in sites with bone height of above 5 mm. According to implant length the survival rates were 100% for 12 mm, 98.7% for 10 mm, 98.7% for 8 mm and only 47.6% for 6 mm implants. Soft tissue parameters (pocket probing depth, probing attachment level, bleeding on probing and marginal bone levels) did not yield any differences between the osteotome-installed and the conventionally placed implants. More than 90% of the patients were satisfied with the implant therapy and would undergo similar therapy again if necessary. The cost associated with implant therapy was considered to be justified. Conclusion: In conclusion, the osteotome technique was a reliable method for implant insertion in the posterior maxilla, especially at sites with 5 mm or more of preoperative residual bone height and a relatively flat sinus floor. [source]

Placement of Brånemark implants in the maxillary tuber region: anatomical considerations, surgical technique and long-term results

CLINICAL ORAL IMPLANTS RESEARCH, Issue 1 2009
Arne Ridell
Abstract Background: Fixture placement in the tuber area is one way to overcome the problem of insufficient bone volume for routine implant surgery in the posterior maxilla due to severe resorption of jawbone and an extensive enlargement of the maxillary sinus. However, little is known about the long-term results. Purpose: The aim of this study was to retrospectively evaluate the survival rate and marginal bone conditions at fixtures placed in the tuber region of the maxilla. Material and methods: Twenty-one patients previously treated with at least one implant in the tuber region of the maxilla were included in this retrospective analysis. A total of 23 standard Brånemark System fixtures with a turned surface had been surgically placed in the tuber regions and 71 additional implants in adjacent areas to support fixed dental bridges. All implants were allowed to heal for 6,8 months before abutment connection and following prosthetic treatment. The patients were radiographed after 1,12 years for evaluation of marginal bone levels. In addition, the relation between the apex of the fixture in the tuberosity area and the posterior border of the maxilla was measured. Results: Twenty of the 21 patients representing 22 tuber and 64 additional implants were radiographically evaluated. No implants in the tuber areas were lost during the follow-up whereas two fixtures in the anterior region had to be removed, one before loading and the other after 4 years of loading not interfering with the prosthesis stability. The mean marginal bone level at tuber implants was situated on average 1.6 mm (SD 1.1, n=22) from the abutment-fixture junction, whilst the other implants showed an average bone level of 1.9 mm (SD 0.8, n=64). The results were similar when comparing partially and totally edentulous patients. Conclusion: The present retrospective study shows good clinical outcome with standard Brånemark fixtures placed in the tuber region of the posterior maxilla using a two-stage procedure. In appropriate cases where bone of adequate volume and density is available, our data indicate that the technique can be used as an alternative to more extensive surgery and especially to the sinus lift procedure. However, prospective comparative studies are needed in order to evaluate the efficacy of the described technique for this purpose. [source]

Bone level changes at implants supporting crowns or fixed partial dentures with or without cantilevers

CLINICAL ORAL IMPLANTS RESEARCH, Issue 10 2008
Gian Andrea Hälg
Abstract Objective: The aim of this study was to analyze whether or not a cantilever extension on a fixed dental prosthesis (FDP) supported by implants increased the amount of peri-implant bone loss or technical complications compared with reconstructions without cantilevers. Materials and Methods: Fifty-four partially dentate patients with a total of 54 FDPs supported by 78 implants were enrolled in the study. Twenty-seven FDPs were with cantilever and 27 FDPs were without cantilever (control group). All FDPs were supported by one or two implants and were located in the posterior maxilla or mandible. The primary outcome variable was change in peri-implant marginal bone level from the time of FDP placement to the last follow-up visit. FDPs were under functional loading for a period of 3 up to 12.7 years. Statistical analysis was carried out with Student's t -test. Regression analyses were carried out to evaluate the influence of confounding factors on the peri-implant bone level change. In addition, implant survival rates were calculated and technical complications assessed. Results: After a mean observation period of 5.3 years, the mean peri-implant bone loss for the FDPs with cantilevers was 0.23 mm (SD±0.63 mm) and 0.09 mm (SD±0.43 mm) for FDPs without cantilever. Concerning the bone level change at implants supporting FDPs with or without cantilevers no statistically significant differences were found. The regression analysis revealed that jaw of implant placement had a statistically significant influence on peri-implant bone loss. When the bone loss in the cantilever group and the control group were compared within the maxilla or mandible separately, no statistically significant difference was found. Implant survival rates reached 95.7% for implants supporting cantilever prostheses and 96.9% for implants of the control group. Five FDPs in the cantilever group showed minor technical complications, none were observed in the control group. Conclusion: Within the limitations of this study it was concluded that cantilever on FDPs did not lead to a higher implant failure rate and did not lead to more bone loss around supporting implants compared with implants supporting conventional FDPs. In contrast to these results more technical complications were observed in the group reconstructed with cantilever. [source]

Immediate and early non-occlusal loading of Straumann implants with a chemically modified surface (SLActive) in the posterior mandible and maxilla: interim results from a prospective multicenter randomized-controlled study

CLINICAL ORAL IMPLANTS RESEARCH, Issue 5 2008
Axel Zöllner
Abstract Objective: Immediate and early loading of dental implants can simplify treatment and increase overall patient satisfaction. The purpose of this 3-year prospective randomized-controlled multicenter study was to assess the differences in survival rates and bone level changes between immediately and early-loaded implants with a new chemically modified surface (SLActive). This investigation shows interim results obtained after 5 months. Material and methods: Patients ,18 years of age missing at least one tooth in the posterior maxilla or mandible were enrolled in the study. Following implant placement, patients received a temporary restoration either on the day of surgery (immediate loading) or 28,34 days after surgery (early loading); restorations consisted of single crowns or two to four unit fixed dental prostheses. Permanent restorations were placed 20,23 weeks following surgery. The primary efficacy variable was change in bone level (assessed by standardized radiographs) from baseline to 5 months; secondary variables included implant survival and success rates. Results: A total of 266 patients were enrolled (118 males and 148 females), and a total of 383 implants were placed (197 and 186 in the immediate and early loading groups, respectively). Mean patient age was 46.3±12.8 years. After 5 months, implant survival rates were 98% in the immediate group and 97% in the early group. Mean bone level change from baseline was 0.81±0.89 mm in the immediate group and 0.56±0.73 mm in the early group (P<0.05). Statistical analysis revealed a significant center effect (P<0.0001) and a significant treatment × center interaction (P=0.008). Conclusions: The results suggested that Straumann implants with an SLActive can be used predictably in time-critical (early or immediate) loading treatment protocols when appropriate patient selection criteria are observed. The mean bone level changes observed from baseline to 5 months (0.56 and 0.81 mm) corresponded to physiological observations from other studies, i.e., were not clinically significant. The presence of a significant center effect and treatment × center interaction indicated that the differences in bone level changes between the two groups were center dependent. [source]

Dental implants placement in conjunction with osteotome sinus floor elevation: a 12-year life-table analysis from a prospective study on 588 ITI®implants

CLINICAL ORAL IMPLANTS RESEARCH, Issue 2 2006
Nicola Ferrigno
Abstract Objectives: The purpose of this prospective study was to evaluate the clinical success of placing ITI dental implants in the posterior maxilla using the osteotome technique. Material and methods: All implants were placed following a one-stage protocol (elevating the sinus floor and placing the implant at the same time). Five hundred and eighty-eight implants were placed in 323 consecutive patients with a residual vertical height of bone under the sinus ranging from 6 to 9 mm. The mean observation follow-up period was 59.7 months (with a range of 12,144 months). This prospective study not only calculated the 12-year cumulative survival and success rates for 588 implants by life-table analysis but also the cumulative success rates for implant subgroups divided per implant length and the percentage of sinus membrane perforation were evaluated. Results: The 12-year cumulative survival and success rates were 94.8% and 90.8%, respectively. The analysis of implant subgroups showed slightly more favourable cumulative success rates for 12 mm long implants (93.4%) compared with 10 and 8 mm long implants (90.5% and 88.9%, respectively). During the study period, only 13 perforations of the Schneiderian membrane were detected with a perforation rate of 2.2% (13 perforations/601 treated sites). Ten perforations out of 13 were caused during the first half of the study period and of these, seven were detected during the first 3 years of this prospective study. Conclusion: Based on the results and within the limits of the present study, it can be concluded that ITI implant placement in conjunction with osteotome sinus floor elevation represents a safe modality of treating the posterior maxilla in areas with reduced bone height subjacent to the sinus as survival and success rates were maintained above 90% for a mean observation period of ,60 months. Shorter implants (8 mm implants) did not significantly fail more than longer ones (10 and 12 mm implants): the differences were small compared with the number of events; hence, no statistical conclusion could be drawn. But, from the clinical point of view, the predictable use of short implants in conjunction with osteotome sinus floor elevation may reduce the indication for complex invasive procedures like sinus lift and bone grafting procedures. [source]

Does platelet-rich plasma promote remodeling of autologous bone grafts used for augmentation of the maxillary sinus floor?

CLINICAL ORAL IMPLANTS RESEARCH, Issue 3 2005
Gerry M. Raghoebar
Abstract: The aim of this study was to evaluate the effect of platelet-rich plasma (PRP) on remodeling of autologous bone grafts used for augmentation of the floor of the maxillary sinus. In five edentulous patients suffering from insufficient retention of their upper denture related to a severely resorbed maxilla, the floor of both maxillary sinus was augmented with an autologous bone graft from the iliac crest. Randomly, PRP was added to the bone graft used to augment the floor of the left or right sinus (split-mouth design). Three months after the reconstruction, bone biopsies were taken with a trephine from the planned implant sites (N=30). Subsequently, three implants were placed in the left and right posterior maxilla. Microradiograms were made of all biopsies (N=30), whereafter the biopsies were processed for light microscopic examination. In addition, clinical parameters were scored. Wound healing was uneventful, clinically no difference was observed between the side treated with PRP or not. Also microradiographical and histomorphological examination of the biopsies revealed no statistical difference between the PRP- and non-PRP side. One implant placed in the PRP side of the graft was lost during the healing phase. Implant-retained overdentures were fabricated 6 months after implantation. All patients functioned well (follow-up 20.2±4.3 months). In this study, no beneficial effect of PRP on wound healing and bone remodeling was observed. It is posed that PRP has no additional value in promoting healing of grafted non-critical size defects. Résumé Le but de cette étude a été d'évaluer l'effet du plasma riche en plaquettes sur le remodelage de greffons osseux autogènes utilisés pour l'épaississement du plancher sinusal. Chez cinq patients édentés souffrant d'une rétention insuffisante de leur prothèse supérieure en relation avec un maxillaire sévèrement résorbé, les planchers sinusaux des deux maxillaires ont étéépaissis avec un greffon d'os autogène provenant de la crête iliaque. Au hasard, du plasma riche en plaquettes (PRP) a été ajouté au greffon osseux utilisé pour épaissir le plancher du sinus gauche ou droit (modèle de bouche divisée). Trois mois après la reconstruction, des biopsies osseuses ont été obtenues avec un trépan des sites planifiés pour placer des implants (N=30). Ensuite, trois implants ont été placés dans les parties maxillaires gauches et droites. Des microradiogrammes des 30 biopsies ont été effectuées, ces dernières ont ensuite été utilisées pour l'examen au microscope optique. De plus, des paramètres cliniques ont été enregistrés. La guérison a été parfaite, cliniquement aucune différence n'a été observée entre les sites traités avec PRP ou sans. L'examen microradiographique et histomorphologique des biopsies n'a révélé aucune différence significative entre les sites PRP et non-PRP. Un implant placé dans le site PRP du greffon a été perdu durant la phase de guérison. Des prothèses retenues sur implants ont été fabriquées six mois après l'insertion des implants. Tous les patients ont une mise en fonction excellente après un suivi de 20±4,3 mois. Dans cette étude, aucun effet bénéfique additionnel du PRP sur la guérison et le remodelage osseux n'a été observé. Le PRP n'aurait aucune valeur supplémentaire à promouvoir la guérison dans ce type d'opération. Zusammenfassung Das Ziel dieser Studie war, den Einfluss von plättchenreichem Plasma auf die Remodellierung von autologen Knochentransplantaten, welche für die Augmentation des Sinusbodens vom Sinus maxillaris verwendet wurden, auszuwerten. Bei 5 zahnlosen Patienten, welche aufgrund einer stark resorbierten Maxilla über einen ungenügenden Halt der Oberkieferprothese klagten, wurde der Sinus maxillaris mit autologem Knochen vom Beckenkamm augmentiert. Zufällig wurde dem Knochen, der zur Augmentation des rechten oder linken Sinusbodens verwendet wurde, plättchenreiches Plasma (PRP) hinzugefügt (unterschiedlich behandelte Seiten). Drei Monate nach der Augmentation wurden mittels Hohlfräsen Biopsien an den geplanten Implantatlokalisationen entnommen (N=30). Danach wurden je drei Implantate in die rechte und linke posteriore Maxilla eingesetzt. Von allen Biopsien wurde Mikroröntgenbilder angefertigt (N=30), danach wurden die Biopsien für die lichtmikroskopische Untersuchung aufgearbeitet. Zusätzlich wurden klinische Parameter aufgenommen. Die Wundheilung war unauffällig. Klinisch konnten keine Unterschiede zwischen den mit und ohne PRP behandelten Seiten beobachtet werden. Ebenso ergab die mikroradiographische und histomorphometrische Untersuchung der Biopsien keine statistisch signifikanten zwischen der PRP und nicht-PRP Seite. Ein Implantat, welches in eine PRP Seite eingesetzt worden war, ging während der Einheilphase verloren. Die implantatgetragenen Hybridprothesen wurden 6 Monate nach Implantation angefertigt. Alle Patienten funktionierten problemlos (Beobachtungszeit bis 20.2±4.3 Monate). In dieser Studie konnte kein positiver Einfluss des PRP auf die Wundheilung und die Knochenremodellierung beobachtet werden. Es wird vermutet, dass PRP keinen zusätzlichen Effekt bei der Förderung der Heilung von Transplantaten in Defekten mit nicht-kritischer Grösse hat. Resumen La intención de este estudio fue evaluar el efecto del plasma rico en plaquetas en el remodelado de injertos de hueso autólogo usado para aumento del suelo del seno maxilar. Se aumentó el suelo de ambos senos maxilares con injertos de hueso autólogo de la cresta iliaca en 5 pacientes edéntulos que padecían de insuficiente retención de su dentadura superior relacionada con un maxilar severamente reabsorbido. Aleatoriamente, se añadió plasma rico en plaquetas (PRP) al injerto óseo usado para aumentar el suelo del seno derecho o izquierdo (diseño de boca partida). Tres meses tras la reconstrucción, se tomaron biopsias de hueso con un trépano de los lugares de implantes planificados (N=30). Subsecuentemente se colocaron tres implantes en el maxilar posterior derecho e izquierdo. Se hicieron microrradiogramas de todas las biopsias (N=30), posteriormente las biopsias se procesaron para microscopía óptica. Además se tomaron parámetros clínicos. La cicatrización de la herida tuvo lugar sin incidentes. Clínicamente no se observó diferencia alguna entre el lado tratado con PRP o no. Tampoco el examen microrradiográfico e histomorfológico de las biopsias revelaron diferencias estadísticamente significativas entre los lados con o sin PRP. Un implante colocado en el lado del PRP se perdió durante la cicatrización. Las dentaduras implantorretenidas se fabricaron a los seis meses de la implantación. Todos los pacientes funcionaron bien (seguimiento de 20.2±4.3 meses). En este estudio no se observó ningún efecto beneficioso del PRP sobre la cicatrización y sobre el remodelado óseo. Se plantea que el PRP no tiene ningún valor adicional en promover la cicatrización de defectos no críticos injertados. [source]

Bone formation at titanium porous oxide (TiUniteÔ) oral implants in type IV bone

CLINICAL ORAL IMPLANTS RESEARCH, Issue 1 2005
Yi-Hao Huang
Abstract Background: Several oral implant design advances have been suggested to overcome poor bone quality, an impediment for successful implant treatment. A novel titanium porous oxide (TPO) surface has been shown to offer favorable results in several settings. The objective of this study was to evaluate the local bone formation and osseointegration at TPO-modified implants in type IV bone. Method: Three TPO surface-modified implants (TiUniteÔ) were installed into the edentulated posterior maxilla in each of 8 Cynomolgus monkeys. The animals were injected with fluorescent bone labels at 2, 3, 4 and 16 weeks post-surgery and were euthanized at week 16 when block biopsies were collected for histologic analysis. Results: The predominant observation of the TPO implant surface was a thin layer of new bone covering most of the implant threads. Mean (±SE) bone,implant contact for the whole study group was 74.1±4.8%. There was a significant variability in bone,implant contact between animals (P=0.0003) and between sites of the same animal (P<0.0001). The variance in bone,implant contact was 30% larger among sites of the same animal than between different animals (187.5 vs. 144.8, respectively). There was a small but significant difference in bone density immediately outside, compared to within the threaded area of the implants (37.1±3.2% vs. 32.1±3.2%, P<0.0001). Bone density outside the implant threads was significantly correlated (,=0.682, P<0.0001) with the bone density within thethreaded area. Bone density within the threaded area was significantly correlated (,=0.493, P=0.0002) with bone,implant contact, whereas bone density outside the implant threads did not have a significant effect (,=0.232, P=0.1). Conclusions: The results suggest that the TPO surface possesses a considerable osteoconductive potential promoting a high level of implant osseointegration in type IV bone in the posterior maxilla. Résumé Différents nouveaux modèles d'implants ont été suggéréspour tenter de compenser la mauvaise qualité osseuse qui est un problème pour le traitement implantaire à succès. Une nouvelle surface en oxyde poreux de titane (TPO) a apporté des résultats favorables en différentes occasions. L'objectif de cette étude a été d'évaluer la formation osseuse locale et l'ostéoïntégration d'implants modifiés TPO dans de l'os de qualité type IV. Trois implants dont la surface était modifiée TPO (TiUniteTM) ont été insérés dans un maxillaire édenté postérieur de huit singes cynomolgus. Les animaux ont subi des injections de marqueurs osseux par flurorescence à deux, trois, quatre et seize semaines après la chirurgie et ont été euthanasiés à la semaine 16 quand des biopsies en bloc ont été prélevées pour l'analyse histologique. L'observation prédominante de la surface implantaire TPO était une fine couche de nouvel os couvrant la plupart des filetages implantaires. La moyenne ±SE du contact os-implant pour tout le groupe étudiéétait de 74±5%. Il y avait une variation significative dans le contact os-implant entre les animaux (P<0,0003) et entre les sites d'un même animal (P<0,0001). La variance du contact os-implant était 30% plus importante parmi les sites du même animal qu'entre différents animaux (respectivement 187 et 145). Il y avait une différence significative bien que faible dans la densité osseuse immédiatement á l'extérieur comparéà l'intérieur des zones à filetage des implants (37±3% vs 32±3%, P<0,0001). La densité osseuse en dehors des filetages implantaires était en corrélation significative (ß=0,682, P<0,0001) avec la densité osseuse à l'intérieur des zones de filetage. La densité osseuse à l'intérieur des zones de filetage était en corrélation significative (ß=0,493, P<0,0002) avec le contact os-implant, tandis que la densité osseuse en dehors des filetages implantaires n'avait pas d'effet significatif (ß=0,232, P=0,1). Ces résultats suggèrent que la surface TPO possède un potentiel ostéoconducteur considérable qui peut promouvoir une ostéoïntégration implantaire de haut niveau dans l'os de type IV dans la région maxillaire postérieure. Zusammenfassung Ziel: Um trotz schlechter Knochenqualität die Aussicht auf eine erfolgreiche implantologische Behandlung zu verbessern, wurden verschiedene Entwicklungen des Designs von Zahnimplantaten vorgeschlagen. Bei verschiedenen Gelegenheiten hat eine neue poröse Titanoxidoberfläche (TPO) scheinbar vorteilhafte Resultate gezeigt. Das Ziel dieser Studie war, die lokale Knochenbildung und die Osseointegration von Implantaten mit einer TPO-modifizierten Oberfläche im Typ IV Knochen zu untersuchen. Methode: In die zahnlosen posterioren Oberkiefern eines jeden von 8 Cynomolgus-Affen implantierte man drei Implantate mit einer TPO-modifizierten Oberfläche (TiUnite®). Den Tieren wurden 2, 3, 4 und 16 Wochen nach dem chirurgischen Eingriff fluoreszierende Knochenmarker injiziert und in der Wochen 16 wurden sie eingeschläfert und für die histologische Analyse Blockbiopsien entnommen. Resultate: Die wichtigste Beobachtung bei der TPO-Implantatoberfläche war eine dünne Schicht neuen Knochens, welche die meisten Schraubenwindungen des Implantates bedeckte. Der mittlere Knochen-Implantatkontakt (±SE) betrug in der ganzen Testgruppe 74.1±4.8%. Man fand eine signifikante Variabilität des Knochen-Implantatkontaktes unterhalb der Tiere (P=0.0003) und auch unterhalb der verschiedenen Impantate desselben Tieres (P<0.0001). Innerhalb der Implantate desselben Tieres war die Varianz des Knochen-Implantatkontaktes bis zu 30% grösser, als zwischen den verschiedenen Tieren (187.5 gegenüber 144.8). Man fand auch einen kleinen, aber signifikanten Unterschied der Knochendichte im Bereich direkt ausserhalb der Schraubenwindungen, verglichen mit dem inneren Bereich (37.1±3.2% gegenüber 32.1±3.2%, P<0.0001). Diese beiden Knochendichten waren aber signifikant miteinander korreliert (0.682, P<0.0001). Die Knochendichte innerhalb der Schraubenwindungen korrelierte signifikant mit dem Knochen-Implantat-Kontakt (ß=0.493, P=0.0002), währenddem die Knochendichte ausserhalb des Bereiches der Schraubenwindungen in dieser Beziehung keine signifikante Korrelation aufwies (ß=0.232, P=0.1). Zusammenfassung: Die Resultate lassen vermuten, dass die TPO-Oberfläche eine beachtliche osteokonduktive Fähigkeit hat, die im posterioren Oberkieferbereich mit Typ IV Knochen zu einer sehr guten Osseointegration führt. Resumen Antecedentes: Se han sugerido varios avances en los diseños de los implantes orales para superar una baja calidad de hueso, un impedimento para un tratamiento exitoso de implantes. Se ha presentado una nueva superficie de óxido de titanio poroso (TPO) que ofrece resultados favorables en diversas situaciones. El objetivo de este estudio fue evaluar la formación local de hueso y la osteointegración en implantes TPO modificados en hueso tipo IV. Método: Se instalaron tres implantes (TiUniteTM) con superficie modificada TPO en el maxilar posterior edéntulo en 8 monos Cynomolgus. Los animales fueron inyectados con marcadores óseos fluorescentes en la semana 2, 3, 4 y 16 tras la cirugía y se sacrificaron en la semana 16 recogiéndose biopsias en bloque para análisis histológicos. Resultados: La observación predominante de la superficie TPO del implante fue una fina capa de hueso nuevo cubriendo la mayor parte de las roscas. El contacto hueso-implante medio (±SE) para todo el grupo de estudio fue de 74.1±4.8%. Hubo una variabilidad significativa en el contacto hueso-implante entre animales (P=0.0003) y entre lugares del mismo animal (P<0.0001). La varianza en el contacto hueso-implante fue un 30% mayor entre lugares del mismo animal que entre los diferentes animales (187.5 vs. 144.8, respectivamente). Hubo una pequeña pero significativa diferencia en la densidad ósea inmediatamente por fuera comparada con el área roscada de los implantes (37.1±3.2% vs. 32.1±3.2%, P<0.0001). La densidad ósea por fuera de las roscas del implante se correlacionó significativamente (,=0.682, P<0.0001) con la densidad ósea entre las áreas de roscas. La densidad ósea entre las áreas de roscas se correlacionó significativamente (,=0.492, P<0.0002) con el contacto hueso implante, mientras que la densidad ósea por fuera de las roscas del implante no tuvo un efecto significativo (,=0.232, P=0.1). Conclusiones: Los resultados sugieren que la superficieTPOposee un considerable potencial osteoconductivo promoviendo un alto nivel de osteointegracióndel implante en hueso tipo IV en el maxilar posterior. [source]

Effects of sinus lifting on voice quality

CLINICAL ORAL IMPLANTS RESEARCH, Issue 6 2003
A prospective study, risk assessment
Abstract: A variety of potential complications associated with sinus lift surgery have been reported in the literature. However, potential alterations of voice quality following sinus elevation have so far not been mentioned or evaluated scientifically. For the majority of patients, slight changes of the voice pattern are of no importance. However, for voice professionals, whose voices have become part of their distinctive profession or trademark, minimal changes may have dramatic consequences. This specific group of patients, such as speakers, actors and singers, depend on the particular quality and timbre of their voice for their livelihood. Consequently, the purpose of this study was to assess the effects of sinus lifting on voice quality in the above patient group. In a collaborative interdisciplinary effort, the Departments of Oral Surgery and Otorhinolaryngology, Section of Phoniatrics and Logopedics, thoroughly evaluated a series of voice parameters of four patients undergoing sinus lifting pre- and postoperatively. The parameters analyzed included pitch, dynamic range, sound pressure level, percent jitter, percent shimmer and noise-to-harmonics ratio with special emphasis on formant analysis. No changes were detected in any of the commonly evaluated parameters. These were rated subjectively by patients and their friends or relatives and objectively with instrumental tools under isolated phoniatric lab conditions. In conclusion, sinus lift surgery appears to be a safe, predictable evidence-based method for regenerating the highly atrophic posterior maxilla, which does not jeopardize the individual characteristic voice pattern of high-profile patients critically dependent on their voices for their livelihood. Résumé Quelques complications potentielles associées à la chirurgie d'épaississement du plancher sinusal ont été rapportées dans la littérature. Les altérations potentielles de la qualité de la voix suivant l'épaississement du plancher sinusal n'ont pas encore été mentionnées et évaluées scientifiquement. Pour la majorité des patients, des petites variations dans le timbre de la voix ne sont pas importantes. Cependant, pour les professionnels de la phonation pour lesquels la voix est devenue une partie importante de leur profession, des variations même faibles peuvent entraîner des conséquences dramatiques. Ce groupe spécifique de patients, tels que les orateurs, les acteurs et les chanteurs dépendent essentiellement de la qualité et du timbre particulier de leur voix dans leur vie professionnelle. Par conséquent, le but de cette étude a été d'estimer les effets d'un épaississement du sinus sur la qualité de la voix dans ce groupe de patients. Dans un effort interdisciplinaire collaboratif, les départements de chirurgie buccale et d'otorhino-laringologie, la section de phonétique et de logopédie ont évalué de manière très précise une série de paramètres de la voix avant et après l'opération chez quatre patients ayant subi un épaississement du sinus maxillare. Les paramètres analysés contenaient la hauteur, l'étalement, le niveau de pression du son, le pourcentage de trac, le pourcentage de chatoiements et la proportion bruit-harmonie avec une insistance spéciale sur l'analyse du formant. Aucun changement n'a été détecté dans aucun des paramètres évalués couramment. Ces derniers étaient estimés subjectivement par les patients et par leurs amis ou parents, et objectivement à l'aide des instruments sous des conditions de laboratoire de phonétique isolé. En conclusion, la chirugie d'épaississement du plancher sinusal semble une méthode sûre, avec un pronostic basé sur l'évidence, permettant de regénérer les maxillaires très atrophiés qui n'empêche pas la caractéristique individuelle de la voix chez des patients avec des profils où la voix est essentielle à leur vie active. Zusammenfassung Der Einfluss einer Sinusbodenelevation auf die Stimmqualität, eine Langzeitstudie und Risikoanalyse. In der Literatur werden eine ganze Reihe von möglichen Komplikationen beschrieben, die bei dem chirurgischen Eingriff der Sinusbodenelevation auftreten können. Veränderungen der Stimme, die als Folge einer Sinusbodenelevation vorkommen können, wurden aber bis heute weder beschrieben, noch wissenschaftlich ausgewertet. Für den Grossteil der Patienten haben leichte Veränderungen der Stimme keine Bedeutung. Für Personen aber, deren Stimme bei der Ausübung ihres Berufes wichtig ist, eventuell ein Teil ihres Berufes oder gar Markenzeichen geworden ist, können kleine Veränderungen dramatische Folgen haben. Diese ausgewählte Gruppe von Patienten, wie zum Beispiel Nachrichtensprecher, Schauspieler oder Sänger, sind im täglichen Leben auf die spezifische Art und den Klang ihrer Stimme angewiesen. Daher war das Ziel dieser Studie, Einflüsse einer Sinusbodenelevation auf die Stimmqualität bei den oben erwähnten Patienten zu untersuchen. In einer interdisziplinären Zusammenarbeit untersuchten die Klinik für Oralchirurgie und Otorhinolaryngologie und die Abteilung für Phonetik und Logopädie an 4 Patienten vor und nach der Sinusbodenelevation sehr eingehend verschiedene Parameter der Stimme. Die untersuchten Parameter waren Tonhöhe, Tonvolumen, den durch den Ton erzeugten Luftdruck, Schwingungen, Vibrationen und das Verhältnis zwischen Nebengeräuschen und harmonischem Klang mit speziellem Augenmerk auf formative Analysen. Man erkannte bei keinem der oben untersuchten Parametern eine Veränderung. Sie wurden sowohl subjektiv durch die Patienten und ihre Freunde oder Verwandten, sowie objektiv mit Messinstrumenten unter absolut schallisolierten Laborbedingungen gemessen. Über die Sinusbodenelevation kann man zusammenfassend sagen, dass es sich um eine sichere, voraussagbare und auf wissenschaftlichen Grundlagen basierende Operationsmethode zum Wiederaufbau einer massiv athrophischen Maxilla im Seitenzahnbereich handelt. Sie gefährdet die individuellen Stimmcharakteristika von kritischen und sehr anspruchsvollen Patienten, die in ihrem täglichen Leben auf ihre charakteristische Stimme angwiesen sind, nicht. Resumen Se han descrito en la literatura una variedad de complicaciones asociadas con la cirugía de la elevación del seno. Pero hasta el momento no se han mencionado ni evaluado científicamente alteraciones potenciales de la calidad de voz tras la elevación del seno. Para la mayoría de los pacientes, pequeños cambios en el patrón de voz no tienen importancia. De todos modos, en los profesionales de la voz, cuyas voces se han convertido en parte distintiva de su profesión o marca, pequeños cambios pueden tener consecuencias dramáticas. Este grupo específico de pacientes, tales como locutores, actores y cantantes, dependen de la calidad particular y timbre de su voz para su sustento. Consecuentemente, el propósito de este estudio fue valorar los efectos de la elevación del seno en la calidad de voz en el anterior grupo de pacientes. En un esfuerzo de colaboración interdisciplinaria, los departamentos de Cirugía Oral y Otorrinolaringología, Sección de Foniatría y Logopedia, evaluaron e profundidad una serie de parámetros de voz de 4 pacientes que se someterían a elevación del seno pre y postoperatoriamente. Los parámetros analizados incluyeron tono, rango dinámico, nivel de presión sonoro, porcentaje de reverberación, porcentaje de tremulación y relación ruido a harmónicos con especial énfasis en el análisis formante. No se detectaron cambios en ninguno de los parámetros evaluados comúnmente. Estos se valoraron subjetivamente por los pacientes y sus amigos o parientes y objetivamente por herramientas instrumentales bajo condiciones de laboratorio de aislamiento foniátrico. En definitiva, la cirugía de elevación del seno parece ser un método seguro, predecible basado en la evidencia para regenerar el maxilar posterior altamente atrófico, que no pone en peligro las características del patrón de voz de los pacientes de características especiales dependientes de manera crítica de sus voces para su sustento. [source]

Freeze-dried bone for maxillary sinus augmentation in sheep

CLINICAL ORAL IMPLANTS RESEARCH, Issue 6 2002
Part II: Biomechanical findings
Abstract: This study examines the biomechanical loading capacity of dental implants placed in the posterior maxilla in conjunction with subantral augmentation with either homogeneous demineralized freeze-dried bone from sheep (s-DFDB) or heterogeneous demineralized freeze-dried human bone (h-DFDB) as grafting material in sheep. In 36 adult female mountain sheep, the Schneiderian membrane was elevated extraorally in both maxillary sinuses, and two titanium plasma-flame-sprayed cylindrical implants were inserted in each lateral antral wall. Three groups of 18 maxillary sinuses each were augmented with s-DFDB, h-DFDB and autogenous bone from the illiac crest, respectively. In the remaining 18 sinuses, the subantral hollow space was left empty. Pull-out tests were carried out after intervals of 12, 16 and 26 weeks. The mean pull-out force needed, irrespective of time, was 259.3 N in the empty control group, 356.7 N in the group augmented with autogenous bone, 278.1 N in the test group augmented with h-DFDB and 365.2 N in the group augmented with s-DFDB, revealing no significant difference between the individual groups (P > 0.05). The implants of the group augmented with autogenous bone showed an increase in the mean pull-out force from 223.8 N after 12 weeks to 523.7 N after 26 weeks. The nonaugmented control group yielded values of 248 N after 12 weeks, which rose to 269.8 N at the last test, while the values of the h-DFDB group increased from 275.4 N to 325.4 N. The highest initial pull-out values were obtained in the s-DFDB group. They amounted to 310.5 N after 12 weeks and rose to 481.4 N after 26 weeks. Time thus proved to have a significant influence on the pull-out forces (P = 0.014) with a statistically proven linear trend (P = 0.007). The findings of this experimental study indicate that the use of homogeneous DFDB in one-stage sinus lift procedures results in a mechanical loading capacity of implants comparable to that achieved by autogenous cancellous bone from the iliac crest. In contrast, the use of heterogenous-DFDB resulted in only slightly higher pull-out forces than those observed in the nonaugmented control group after 26 weeks. [source]