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Lars Sennerby - One of the best experts on this subject based on the ideXlab platform.

  • evaluation of a novel cone beam computed tomography scanner for bone density examinations in preoperative 3d reconstructions and correlation with Primary Implant Stability
    Clinical Implant Dentistry and Related Research, 2015
    Co-Authors: Lars Sennerby, Peter Andersson, Luca Pagliani, Claudio Giani, Giacomo Moretti, Massimo Molinari, Alessandro Motroni
    Abstract:

    Background Bone density examination (BDE) using preoperative cone beam computed tomography (CBCT) might be used to predict Primary Implant Stability in Implant patients. Purpose The aim of the study was to validate a novel CBCT scanner in vitro with regard to BDE in preoperative scans and to analyze the in vivo correlation of CBCT scan results with Primary Implant Stability measurements. Materials and Methods A CBCT scanner was validated in vitro with regard to spatial uniformity and linearity of CT numbers (Hounsfield units, HU) by using a series of phantoms and plastic and hydroxyapatite specimens of various densities. Forty-nine patients (27 female and 22 male, mean age 55.6 ± 9.8) were scanned prior to and 1 to 6 months after the placement of 155 dental Implants of different lengths and diameters. Mean and peak insertion torque (IT) in Ncm were registered during Implant placement. Resonance frequency analysis (RFA) measurements in ISQ units were performed after placement. The second scan was used to export and superimpose the exact positions of bone and Implants into the first scan. Virtual probes with the same length as the actual Implant were automatically placed at the Implant sites, and mean HU values were measured in a 1 mm–wide circular corridor from the tip of the threads and out. Results The in vitro validation showed high uniformity and linearity of CT numbers (HU). The clinical study showed significant correlations between bone density and ISQ, mean IT, and peak IT, respectively. Conclusions The WhiteFox CBCT scanner measures bone density with high accuracy. There is a correlation between bone density and Primary Implant Stability as assessed with IT and RFA measurements. The findings suggest that BDE may be used as an additional feature in treatment-planning software to estimate Primary Stability at predetermined Implant sites.

  • biomechanical aspects of Primary Implant Stability a human cadaver study
    Clinical Implant Dentistry and Related Research, 2009
    Co-Authors: Ilser Turkyilmaz, Lars Sennerby, Edwin A. Mcglumphy, Tolga F. Tözüm
    Abstract:

    Background: The quality of bone is an important factor in the successful Implant treatment, and it is evident that higher Implant failure is more likely in poor quality of bone. The Primary Stability of oral Implants related to resistance to micromotion during healing is influenced by bone quality, surgical technique, and Implant design. Purposes: The aims of this biomechanical study were to explore the effect of bone quality on initial intraosseous Stability of Implants, and to determine the correlations between the bone quality and Implant Stability parameters. Materials and Methods: Twenty-four Implants (Neoss Ltd., Molnlycke, Sweden) were placed into anterior and posterior regions of three human cadaver mandibles. The bone densities of Implant recipient sites were preoperatively determined using computerized tomography (CT) in Hounsfield unit (HU). The maximum insertion torque values were recorded, and Primary Implant Stability measurements were noninvasively performed by means of resonance frequency analysis (RFA). Results: The bone density values ranged from −267 HU to 553 HU. It was found that mean bone density, insertion torque, and RFA values were 113 ± 270 HU, 41.9 ± 5 Ncm, and 70 ± 7 Implant Stability quotient (ISQ), respectively. Statistically significant correlations were found between bone density and insertion torque values (r = 0.690, p < .001); bone density and ISQ values (r = 0.557, p < .05); and insertion torque and ISQ values (r = 0.853, p < .001). Conclusion: CT is a useful tool to assess bone quantity and quality in Implant recipient sites, and bone density has a prevailing effect on Implant Stability at placement.

  • Biomechanical aspects of Primary Implant Stability: a human cadaver study.
    Clinical Implant Dentistry and Related Research, 2008
    Co-Authors: Ilser Turkyilmaz, Lars Sennerby, Edwin A. Mcglumphy, Tolga F. Tözüm
    Abstract:

    Background: The quality of bone is an important factor in the successful Implant treatment, and it is evident that higher Implant failure is more likely in poor quality of bone. The Primary Stability of oral Implants related to resistance to micromotion during healing is influenced by bone quality, surgical technique, and Implant design. Purposes: The aims of this biomechanical study were to explore the effect of bone quality on initial intraosseous Stability of Implants, and to determine the correlations between the bone quality and Implant Stability parameters. Materials and Methods: Twenty-four Implants (Neoss Ltd., Molnlycke, Sweden) were placed into anterior and posterior regions of three human cadaver mandibles. The bone densities of Implant recipient sites were preoperatively determined using computerized tomography (CT) in Hounsfield unit (HU). The maximum insertion torque values were recorded, and Primary Implant Stability measurements were noninvasively performed by means of resonance frequency analysis (RFA). Results: The bone density values ranged from −267 HU to 553 HU. It was found that mean bone density, insertion torque, and RFA values were 113 ± 270 HU, 41.9 ± 5 Ncm, and 70 ± 7 Implant Stability quotient (ISQ), respectively. Statistically significant correlations were found between bone density and insertion torque values (r = 0.690, p 

  • Resonance frequency analysis measurements of Implants at placement surgery.
    International Journal of Prosthodontics, 2006
    Co-Authors: Parolov Ostman, Mats Hellman, Inger Wendelhag, Lars Sennerby
    Abstract:

    Purpose The knowledge of what levels of Primary Stability can be obtained in different jawbone regions and of what factors influence Primary Stability is limited. The objective of this study was to evaluate Primary Stability by resonance frequency analysis (RFA) measurements of Implants placed according to a surgical protocol that aimed for high Primary Stability. The aim was also to correlate RFA measurements with factors related to the surgical technique, the patient, and Implant design. Materials and methods A total of 905 Branemark dental Implants used in 267 consecutive patients were measured with RFA at the time of placement surgery. Results A mean ISQ value of 67.4 (SD 8.6) was obtained for all Implants. Univariate analyses with the Implant or patient as unit showed higher ISQ values in men compared with women, in mandibles compared with maxillae, in posterior compared with anterior sites, and for wide-platform Implants in comparison with regular/narrow-platform Implants. There was a correlation between bone quality and Primary Stability, with lower ISQ values obtained for Implants placed in softer bone. A lower Stability was seen with increased Implant length. A stepwise multiple regression analysis using the patient as unit showed that jaw type and gender had independent effects on Primary Stability. Conclusion The results suggest that factors related to bone density and Implant diameter/length may affect the level of Primary Implant Stability. Furthermore, greater Stability was observed in male than in female patients. High Primary Implant Stability was achieved in all jaw regions, although the use of thinner drills and/or tapered Implants cannot fully compensate for the effect of soft bone. The research design does not permit conclusions regarding long-term treatment outcome with Implants.

  • direct Implant loading in the edentulous maxilla using a bone density adapted surgical protocol and Primary Implant Stability criteria for inclusion
    Clinical Implant Dentistry and Related Research, 2005
    Co-Authors: Parolov Ostman, Mats Hellman, Lars Sennerby
    Abstract:

    Background: Long healing periods and submerged Implant placement are commonly used in the maxilla. This extends the time of oral handicap and makes the use of immediate loading protocols an attractive option. The current clinical literature on direct loading of dental Implants in the maxilla is limited. Purpose: The purpose of this prospective clinical study was to evaluate the clinical outcome and Stability of directly loaded Branemark System® or Replace Select® Tapered Implants (Nobel Biocare AB, Goteborg, Sweden) after using a modified surgical protocol and inclusion by Primary Implant Stability. In addition, a reference group treated according to a two-stage protocol was used for comparison. Materials and Methods: Twenty patients planned for prosthetic rehabilitation with Implant-supported bridges in the edentulous maxilla participated in the study group. The final decision on immediate loading was made after Implant placement using insertion torque and resonance frequency analysis (RFA) as acceptance criteria. All patients were included, and 123 oxidized Implants (TiUnite™, Nobel Biocare AB) were placed using a surgical protocol for enhanced Primary Stability. A screw-retained temporary bridge was delivered within 12 hours and a final bridge within 3 months of Implant placement. The patients were monitored through clinical and radiographic follow-up examinations from Implant placement to at least 12 months. Marginal bone level was measured at bridge delivery and after 12 months of loading. Additional RFA measurements were made after 6 months of loading. A reference group comprising 20 patients with 120 Implants treated according to a two-stage protocol was used for comparison. Results: One (0.8%) of the 123 Implants in the study group failed, and no Implant was lost in the reference group. The cumulative survival rates after 12 months of loading were thus 99.2% and 100% for immediate and delayed loading protocols, respectively. The marginal bone resorption was 0.78 (SD 0.9) in the study group and 0.91 (SD 1.04) in the reference group. RFA showed a mean value of 62.9 (SD 4.9) Implant Stability quotient (ISQ) at placement and 64.5 (SD 4.8) ISQ after 6 months for immediately loaded Implants (not significant). The corresponding figures for the reference groups were 61.3 (SD 8.8) ISQ and 62.6 (SD 7.0) ISQ (not significant). There were no statistically significant differences between the groups at any time point. Conclusion: The use of six to seven Implants for immediate loading of a fixed provisional bridge is a viable option for Implant treatment of the edentulous maxilla, at least when good Primary Implant Stability can be ensured.

Matthias Karl - One of the best experts on this subject based on the ideXlab platform.

  • Evaluation of Insertion Energy as Novel Parameter for Dental Implant Stability.
    Journal of Clinical Medicine, 2020
    Co-Authors: Tanja Grobecker-karl, Matthias Karl, Anthony Dickinson, Siegfried Heckmann, Constanze Steiner
    Abstract:

    Insertion energy has been advocated as a novel measure for Primary Implant Stability, but the effect of Implant length, diameter, or surgical protocol remains unclear. Twenty Implants from one specific bone level Implant system were placed in layered polyurethane foam measuring maximum insertion torque, torque–time curves, and Primary Stability using resonance frequency analysis (RFA). Insertion energy was calculated as area under torque–time curve applying the trapezoidal formula. Statistical analysis was based on analysis of variance, Tukey honest differences tests and Pearson’s product moment correlation tests (α = 0.05). Implant Stability (p = 0.01) and insertion energy (p < 0.01) differed significantly among groups, while maximum insertion torque did not (p = 0.17). Short Implants showed a significant decrease in Implant Stability (p = 0.01), while reducing Implant diameter did not cause any significant effect. Applying the drilling protocol for dense bone resulted in significantly increased insertion energy (p = 0.02) but a significant decrease in Implant Stability (p = 0.04). Insertion energy was not found to be a more reliable parameter for evaluating Primary Implant Stability when compared to maximum insertion torque and resonance frequency analysis.

  • Insertion torque/time integral as a measure of Primary Implant Stability.
    Biomedizinische Technik, 2020
    Co-Authors: Tanja Grobecker-karl, Matthias Karl, Constanze Steiner
    Abstract:

    The goal of this in vitro study was to determine the insertion torque/time integral for three Implant systems. Bone level Implants (n = 10; BLT - Straumann Bone Level Tapered 4.1 mm × 12 mm, V3 - MIS V3 3.9 mm × 11.5 mm, ASTRA - Dentsply-Sirona ASTRA TX 4.0 mm × 13 mm) were placed in polyurethane foam material consisting of a trabecular and a cortical layer applying protocols for medium quality bone. Besides measuring maximum insertion torque and Primary Implant Stability using resonance frequency analysis (RFA), torque time curves recorded during insertion were used for calculating insertion torque/time integrals. Statistical analysis was based on ANOVA, Tukey's honest differences test and Pearson product moment correlation (α = 0.05). Significantly greater mean maximum insertion torque (59.9 ± 4.94 Ncm) and mean maximum insertion torque/time integral (961.64 ± 54.07 Ncm∗s) were recorded for BLT Implants (p < 0.01). V3 showed significantly higher mean maximum insertion torque as compared to ASTRA (p < 0.01), but significantly lower insertion torque/time integral (p < 0.01). Primary Implant Stability did not differ significantly among groups. Only a single weak (r = 0.61) but significant correlation could be established between maximum insertion torque and insertion torque/time integral (p < 0.01) when all data from all three Implant groups were pooled. Implant design (length, thread pitch) seems to affect insertion torque/time integral more than maximum insertion torque.

  • A Pilot Animal Study Aimed at Assessing the Mechanical Quality of Regenerated Alveolar Bone.
    International Journal of Oral & Maxillofacial Implants, 2020
    Co-Authors: Matthias Karl, Victor Palarie, Viorel Nacu, Tanja Grobecker-karl
    Abstract:

    PURPOSE Bone regeneration procedures are often evaluated based on biologic aspects only. As regenerated bone also has to ensure Primary Implant Stability, the goal of this study was to determine the mechanical quality of regenerated bone. MATERIALS AND METHODS Six adult minipigs were allocated for this experiment with four mandibular study sites each established following tooth removal. Two different types of bovine bone mineral as well as autogenous bone were used for augmenting three-walled defects, while native bone served as the control. Implants were placed after 12, 18, and 24 weeks of healing, and bone quality was determined using intraoperative compressive testing (BoneProbe), insertion torque measurements, and resonance frequency analysis. The mandibles were then harvested for determining bone mineral density (BMD) and bone-to-Implant contact (BIC). Statistical analysis was based on two-way analysis of variance of aligned rank transformed data and Spearman's rank correlation tests (α = .05). RESULTS The effects of the factors healing time and material on the parameters tested were too small to be significant (P ranging from .34 to .98). Weak correlations were observed for Implant insertion torque with BoneProbe measurements in the cortical (0.481; P = .032) and in the trabecular area (0.639; P = .002). BoneProbe measurements in the trabecular part and in the cortical part also correlated with each other (0.477; P = .035). CONCLUSION While differences may exist between bone regenerated using different biomaterials with respect to biologic behavior, differences in the mechanical properties determining Primary Implant Stability seem to be minor. Implant insertion torque measurements appear to be a reliable tool for determining bone quality if only one specific Implant type is considered.

  • Does intraoperative bone density testing correlate with parameters of Primary Implant Stability? A pilot study in minipigs.
    Clinical and experimental dental research, 2019
    Co-Authors: Tanja Grobecker-karl, Victor Palarie, Sonja Schneider, Matthias Karl
    Abstract:

    Objectives Bone density, surgical protocol, and Implant design are the major determinants of Primary Stability. The goal of this animal trial was to investigate potential correlations of intraoperative bone density testing with clinical and histologic parameters of Primary Implant Stability. Material and methods Following extractions of all mandibular premolars and subsequent healing, four Implants each were placed in a total of four minipigs. Bone density was determined by applying intraoperative compressive tests using a device named BoneProbe whereas measurements of Implant insertion torque and resonance frequency analysis were used for evaluating Implant Stability. Bone mineral density (BMD) and bone to Implant contact were quantified after harvesting mandibular block sections. Spearman rank correlation tests were performed for evaluating correlations (α = .05). Results Due to variation in clinical measurements, only weak correlations could be identified. A positive correlation was found between the parameters bone to Implant contact and BMD (Spearman's rho .53; p = .05) whereas an inverse correlation was observed between BMD and Implant Stability (Spearman's rho -.61; p = .03). Both BoneProbe measurements in the cortical and trabecular area positively correlated with Implant insertion torque (Spearman's rho 0.60; p = .02). A slightly stronger correlation was observed between the average of both BoneProbe measurements and Implant insertion torque (Spearman's rho.66; p = .01). Conclusions While establishing exact relationships among parameters of Implant Stability and the measurement techniques applied would require greater sample size, intraoperative compressive testing of bone might, despite the weak correlations seen here, be a useful tool for predicting Primary Implant Stability.

  • Reliability of clinical techniques for evaluating alveolar bone quality and Primary Implant Stability.
    Quintessence International, 2019
    Co-Authors: Matthias Karl, Thomas Buder, Tim Krafft, Tanja Grobecker-karl
    Abstract:

    Objective: A novel device for intraoperative compressive testing of alveolar bone during Implant surgery has been introduced. It was the goal of this study to compare the performance of this device with traditional methods used for determining alveolar bone quality and Primary Implant Stability. Method and materials: Implant surgery in human cadaver bone was performed by two Implantologists differing in experience. Bone quality was rated radiographically, based on tactile sensation during drilling and using intraoperative compressive tests. Implant Stability was evaluated using insertion torque measurements and resonance frequency analysis. Statistical analysis was based on two way ANOVA followed by Tukey multiple comparisons and Pearson's product moment correlation. The level of significance was set at α = .05. Results: Human cadaver bone was ranked according to Implant insertion torque. Radiographic assessment, tactile sensation during drilling, and Implant Stability measurements did not allow differentiating bone types in all instances. Cortical BoneProbe measurements showed a significant trend towards higher measurement values in greater bone quality types (P < .01); in trabecular bone this trend was also present but was not statistically significant. Significant correlations existed between BoneProbe measurements and most other parameters evaluated. Conclusion: Despite the limited number of measurements performed, intraoperative compressive testing of bone may be an option for objectively classifying alveolar bone quality.

Minas Leventis - One of the best experts on this subject based on the ideXlab platform.

  • Alveolar Ridge Preservation Using a Novel Synthetic Grafting Material: A Case with Two-Year Follow-Up
    Case Reports in Dentistry, 2018
    Co-Authors: Peter Fairbairn, Minas Leventis, Chas Mangham, Robert A Horowitz
    Abstract:

    This case report highlights the use of a novel in situ hardening synthetic (alloplastic), resorbable, bone grafting material composed of beta tricalcium phosphate and calcium sulfate, for alveolar ridge preservation. A 35-year-old female patient was referred by her general dentist for extraction of the mandibular right first molar and rehabilitation of the site with a dental Implant. The nonrestorable tooth was “atraumatically” extracted without raising a flap, and the socket was immediately grafted with the synthetic biomaterial and covered with a hemostatic fleece. No membrane was used, and the site was left uncovered without obtaining Primary closure, in order to heal by secondary intention. After 12 weeks, the architecture of the ridge was preserved, and clinical observation revealed excellent soft tissue healing without loss of attached gingiva. At reentry for placement of the Implant, a bone core biopsy was obtained, and Primary Implant Stability was measured by final seating torque and resonance frequency analysis. Histological analysis revealed pronounced bone regeneration while high levels of Primary Implant Stability were recorded. The Implant was successfully loaded 12 weeks after placement. Clinical and radiological follow-up examination at two years revealed stable and successful results regarding biological, functional, and esthetic parameters.

  • minimally invasive alveolar ridge preservation utilizing an in situ hardening β tricalcium phosphate bone substitute a multicenter case series
    International Journal of Dentistry, 2016
    Co-Authors: Minas Leventis, Peter Fairbairn, Ashish Kakar, Angelos D Leventis, Walter Luckerath, Annette Lindner, Vasileios Margaritis, Robert A Horowitz, Heiner Nagursky
    Abstract:

    Ridge preservation measures, which include the filling of extraction sockets with bone substitutes, have been shown to reduce ridge resorption, while methods that do not require Primary soft tissue closure minimize patient morbidity and decrease surgical time and cost. In a case series of 10 patients requiring single extraction, in situ hardening beta-tricalcium phosphate (β-TCP) granules coated with poly(lactic-co-glycolic acid) (PLGA) were utilized as a grafting material that does not necessitate Primary wound closure. After 4 months, clinical observations revealed excellent soft tissue healing without loss of attached gingiva in all cases. At reentry for Implant placement, bone core biopsies were obtained and Primary Implant Stability was measured by final seating torque and resonance frequency analysis. Histological and histomorphometrical analysis revealed pronounced bone regeneration (24.4 ± 7.9% new bone) in parallel to the resorption of the grafting material (12.9 ± 7.7% graft material) while high levels of Primary Implant Stability were recorded. Within the limits of this case series, the results suggest that β-TCP coated with polylactide can support new bone formation at postextraction sockets, while the properties of the material improve the handling and produce a stable and porous bone substitute scaffold in situ, facilitating the application of noninvasive surgical techniques.

Heiner Nagursky - One of the best experts on this subject based on the ideXlab platform.

  • minimally invasive alveolar ridge preservation utilizing an in situ hardening β tricalcium phosphate bone substitute a multicenter case series
    International Journal of Dentistry, 2016
    Co-Authors: Minas Leventis, Peter Fairbairn, Ashish Kakar, Angelos D Leventis, Walter Luckerath, Annette Lindner, Vasileios Margaritis, Robert A Horowitz, Heiner Nagursky
    Abstract:

    Ridge preservation measures, which include the filling of extraction sockets with bone substitutes, have been shown to reduce ridge resorption, while methods that do not require Primary soft tissue closure minimize patient morbidity and decrease surgical time and cost. In a case series of 10 patients requiring single extraction, in situ hardening beta-tricalcium phosphate (β-TCP) granules coated with poly(lactic-co-glycolic acid) (PLGA) were utilized as a grafting material that does not necessitate Primary wound closure. After 4 months, clinical observations revealed excellent soft tissue healing without loss of attached gingiva in all cases. At reentry for Implant placement, bone core biopsies were obtained and Primary Implant Stability was measured by final seating torque and resonance frequency analysis. Histological and histomorphometrical analysis revealed pronounced bone regeneration (24.4 ± 7.9% new bone) in parallel to the resorption of the grafting material (12.9 ± 7.7% graft material) while high levels of Primary Implant Stability were recorded. Within the limits of this case series, the results suggest that β-TCP coated with polylactide can support new bone formation at postextraction sockets, while the properties of the material improve the handling and produce a stable and porous bone substitute scaffold in situ, facilitating the application of noninvasive surgical techniques.

Tanja Grobecker-karl - One of the best experts on this subject based on the ideXlab platform.

  • Evaluation of Insertion Energy as Novel Parameter for Dental Implant Stability.
    Journal of Clinical Medicine, 2020
    Co-Authors: Tanja Grobecker-karl, Matthias Karl, Anthony Dickinson, Siegfried Heckmann, Constanze Steiner
    Abstract:

    Insertion energy has been advocated as a novel measure for Primary Implant Stability, but the effect of Implant length, diameter, or surgical protocol remains unclear. Twenty Implants from one specific bone level Implant system were placed in layered polyurethane foam measuring maximum insertion torque, torque–time curves, and Primary Stability using resonance frequency analysis (RFA). Insertion energy was calculated as area under torque–time curve applying the trapezoidal formula. Statistical analysis was based on analysis of variance, Tukey honest differences tests and Pearson’s product moment correlation tests (α = 0.05). Implant Stability (p = 0.01) and insertion energy (p < 0.01) differed significantly among groups, while maximum insertion torque did not (p = 0.17). Short Implants showed a significant decrease in Implant Stability (p = 0.01), while reducing Implant diameter did not cause any significant effect. Applying the drilling protocol for dense bone resulted in significantly increased insertion energy (p = 0.02) but a significant decrease in Implant Stability (p = 0.04). Insertion energy was not found to be a more reliable parameter for evaluating Primary Implant Stability when compared to maximum insertion torque and resonance frequency analysis.

  • Insertion torque/time integral as a measure of Primary Implant Stability.
    Biomedizinische Technik, 2020
    Co-Authors: Tanja Grobecker-karl, Matthias Karl, Constanze Steiner
    Abstract:

    The goal of this in vitro study was to determine the insertion torque/time integral for three Implant systems. Bone level Implants (n = 10; BLT - Straumann Bone Level Tapered 4.1 mm × 12 mm, V3 - MIS V3 3.9 mm × 11.5 mm, ASTRA - Dentsply-Sirona ASTRA TX 4.0 mm × 13 mm) were placed in polyurethane foam material consisting of a trabecular and a cortical layer applying protocols for medium quality bone. Besides measuring maximum insertion torque and Primary Implant Stability using resonance frequency analysis (RFA), torque time curves recorded during insertion were used for calculating insertion torque/time integrals. Statistical analysis was based on ANOVA, Tukey's honest differences test and Pearson product moment correlation (α = 0.05). Significantly greater mean maximum insertion torque (59.9 ± 4.94 Ncm) and mean maximum insertion torque/time integral (961.64 ± 54.07 Ncm∗s) were recorded for BLT Implants (p < 0.01). V3 showed significantly higher mean maximum insertion torque as compared to ASTRA (p < 0.01), but significantly lower insertion torque/time integral (p < 0.01). Primary Implant Stability did not differ significantly among groups. Only a single weak (r = 0.61) but significant correlation could be established between maximum insertion torque and insertion torque/time integral (p < 0.01) when all data from all three Implant groups were pooled. Implant design (length, thread pitch) seems to affect insertion torque/time integral more than maximum insertion torque.

  • A Pilot Animal Study Aimed at Assessing the Mechanical Quality of Regenerated Alveolar Bone.
    International Journal of Oral & Maxillofacial Implants, 2020
    Co-Authors: Matthias Karl, Victor Palarie, Viorel Nacu, Tanja Grobecker-karl
    Abstract:

    PURPOSE Bone regeneration procedures are often evaluated based on biologic aspects only. As regenerated bone also has to ensure Primary Implant Stability, the goal of this study was to determine the mechanical quality of regenerated bone. MATERIALS AND METHODS Six adult minipigs were allocated for this experiment with four mandibular study sites each established following tooth removal. Two different types of bovine bone mineral as well as autogenous bone were used for augmenting three-walled defects, while native bone served as the control. Implants were placed after 12, 18, and 24 weeks of healing, and bone quality was determined using intraoperative compressive testing (BoneProbe), insertion torque measurements, and resonance frequency analysis. The mandibles were then harvested for determining bone mineral density (BMD) and bone-to-Implant contact (BIC). Statistical analysis was based on two-way analysis of variance of aligned rank transformed data and Spearman's rank correlation tests (α = .05). RESULTS The effects of the factors healing time and material on the parameters tested were too small to be significant (P ranging from .34 to .98). Weak correlations were observed for Implant insertion torque with BoneProbe measurements in the cortical (0.481; P = .032) and in the trabecular area (0.639; P = .002). BoneProbe measurements in the trabecular part and in the cortical part also correlated with each other (0.477; P = .035). CONCLUSION While differences may exist between bone regenerated using different biomaterials with respect to biologic behavior, differences in the mechanical properties determining Primary Implant Stability seem to be minor. Implant insertion torque measurements appear to be a reliable tool for determining bone quality if only one specific Implant type is considered.

  • Does intraoperative bone density testing correlate with parameters of Primary Implant Stability? A pilot study in minipigs.
    Clinical and experimental dental research, 2019
    Co-Authors: Tanja Grobecker-karl, Victor Palarie, Sonja Schneider, Matthias Karl
    Abstract:

    Objectives Bone density, surgical protocol, and Implant design are the major determinants of Primary Stability. The goal of this animal trial was to investigate potential correlations of intraoperative bone density testing with clinical and histologic parameters of Primary Implant Stability. Material and methods Following extractions of all mandibular premolars and subsequent healing, four Implants each were placed in a total of four minipigs. Bone density was determined by applying intraoperative compressive tests using a device named BoneProbe whereas measurements of Implant insertion torque and resonance frequency analysis were used for evaluating Implant Stability. Bone mineral density (BMD) and bone to Implant contact were quantified after harvesting mandibular block sections. Spearman rank correlation tests were performed for evaluating correlations (α = .05). Results Due to variation in clinical measurements, only weak correlations could be identified. A positive correlation was found between the parameters bone to Implant contact and BMD (Spearman's rho .53; p = .05) whereas an inverse correlation was observed between BMD and Implant Stability (Spearman's rho -.61; p = .03). Both BoneProbe measurements in the cortical and trabecular area positively correlated with Implant insertion torque (Spearman's rho 0.60; p = .02). A slightly stronger correlation was observed between the average of both BoneProbe measurements and Implant insertion torque (Spearman's rho.66; p = .01). Conclusions While establishing exact relationships among parameters of Implant Stability and the measurement techniques applied would require greater sample size, intraoperative compressive testing of bone might, despite the weak correlations seen here, be a useful tool for predicting Primary Implant Stability.

  • Reliability of clinical techniques for evaluating alveolar bone quality and Primary Implant Stability.
    Quintessence International, 2019
    Co-Authors: Matthias Karl, Thomas Buder, Tim Krafft, Tanja Grobecker-karl
    Abstract:

    Objective: A novel device for intraoperative compressive testing of alveolar bone during Implant surgery has been introduced. It was the goal of this study to compare the performance of this device with traditional methods used for determining alveolar bone quality and Primary Implant Stability. Method and materials: Implant surgery in human cadaver bone was performed by two Implantologists differing in experience. Bone quality was rated radiographically, based on tactile sensation during drilling and using intraoperative compressive tests. Implant Stability was evaluated using insertion torque measurements and resonance frequency analysis. Statistical analysis was based on two way ANOVA followed by Tukey multiple comparisons and Pearson's product moment correlation. The level of significance was set at α = .05. Results: Human cadaver bone was ranked according to Implant insertion torque. Radiographic assessment, tactile sensation during drilling, and Implant Stability measurements did not allow differentiating bone types in all instances. Cortical BoneProbe measurements showed a significant trend towards higher measurement values in greater bone quality types (P < .01); in trabecular bone this trend was also present but was not statistically significant. Significant correlations existed between BoneProbe measurements and most other parameters evaluated. Conclusion: Despite the limited number of measurements performed, intraoperative compressive testing of bone may be an option for objectively classifying alveolar bone quality.