Insertion Torque Data Research Articles

Novel approach for underpreparation protocol in dental implant with low bone quality depending on hounsfield unit presurgically

Objective: The purpose of this research was to adapt a normal or undersized implant preparation protocol for different bone densities depending on the density measure (Implant stability quotient ISQ, Newton centimeter NCM) and from Cone Beam Computed Tomography reading pre-surgically. To eliminate the need for practice and experience in inserting implants in poor bone quality areas to enhance implant primary stability and survival rate. Material and methods: Fifty-nine patients were selected for inclusion in the study. A total of fifty-nine implants were placed. Insertion torque data were recorded, resonance frequency analysis measurements were taken at first stage surgery, and Hounsfield Unit HU was assessed before surgery and kept hidden to prevent bias. The implant preparation protocol divided the patients into two groups whether standard or undersized, which was determined according to the tactile sensation of the operator. Depending on primary stability measures (ISQ, NCM) samples were divided into 4 subgroups. Finally, HU measurements were taken from subgroups with high stability measures to assess whether to do a standard or underprepared surgical preparation. Result: the result showed a positive and strong correlation with a high significance between ISQ, HU, and insertion torque.

Relation Between Insertion Torque and Implant Stability Quotient: A Clinical Study.

Objectives This study aimed to assess the relation between the insertion torque and implant stability quotient (ISQ recorded immediately and 6 months after implant placement). Materials and Methods Twenty-five patients over the age of 18 years were selected for this study. One implant was placed per patient after tooth extraction. All implants had the same size (11.5 × 3.75 mm) and brand (Hexagonal Morse cone, DSP Biomedical). The insertion torque (Ncm) and resonance frequency analysis (ISQ value) (Osstell Mentor) were used to assess the primary stability (on the day of surgery). After 6 months, resonance frequency analysis was used to assess the secondary stability of each implant. Statistical Analysis The insertion torque data were correlated with ISQ measurements by using Pearson’s correlation. The significance level was 5%. Results There was a positive correlation between insertion torque and initial ISQ (correlation: 0.457; p = 0.022); however, no correlation was found between insertion torque and final ISQ ( p = 0.308). Conclusion The present study demonstrated that there is a positive correlation between the insertion torque and the initial ISQ. Therefore, the higher the insertion torque, the higher the initial ISQ (and vice versa).

Relationship Between Primary/Mechanical and Secondary/Biological Implant Stability.

This systematic review was prepared as part of the Academy of Osseointegration (AO) 2018 Summit, held August 8-10 in Oak Brook Hills, Illinois, to assess the relationship between the primary (mechanical) and secondary (biological) implant stability. Electronic and manual searches were conducted by two independent examiners in order to address the following issues. Meta-regression analyses explored the relationship between primary stability, as measured by insertion torque (IT) and implant stability quotient (ISQ), and secondary stability, by means of survival and peri-implant marginal bone loss (MBL). Overall, 37 articles were included for quantitative assessment. Of these, 17 reported on implant stability using only resonance frequncy analysis (RFA), 11 used only IT data, 7 used a combination of RFA and IT, and 2 used only the Periotest. The following findings were reached: ·Relationship between primary and secondary implant stability: Strong positive statistically significant relationship (P < .001). ·Relationship between primary stability by means of ISQ and implant survival: No statistically significant relationship (P = .4). ·Relationship between IT and implant survival: No statistically significant relationship (P = .2). ·Relationship between primary stability by means of ISQ unit and MBL: No statistically significant relationship (P = .9). ·Relationship between IT and MBL: Positive statistically significant relationship (P = .02). ·Accuracy of methods and devices to assess implant stability: Insufficient data to address this issue. Data suggest that primary/mechanical stability leads to more efficient achievement of secondary/biological stability, but the achievement of high primary stability might be detrimental for bone level stability. While current methods/devices for tracking implant stability over time can be clinically useful, a robust connection between existing stability metrics with implant survival remains inconclusive.

Influence of Stepped Osteotomy on Primary Stability of Implants Inserted in Low-Density Bone Sites: An In Vitro Study.

The aims of this study were to evaluate the ability of a stepped osteotomy to improve dental implant primary stability in low-density bone sites and to investigate possible correlations between primary stability parameters. The study was performed on fresh humid bovine bone classified as type III. The test group consisted of 30 Astra Tech EV implants inserted following the protocol provided by the manufacturer. The first control group consisted of 30 Astra Tech EV implants inserted in sites without the underpreparation of the apical portion. The second control group consisted of 30 Astra Tech TX implants inserted following the protocol provided by the manufacturer. Implant insertion was performed at the predetermined 30 rpm. The insertion torque data were recorded and exported as a curve; using a trapezoidal integration technique, the area underlying the curve was calculated: this area represents the variable torque work (VTW). Peak insertion torque (pIT) and resonance frequency analysis (RFA) were also recorded. A Mann-Whitney test showed that the mean VTW was significantly higher in the test group compared with the first control and second control groups; furthermore, statistical analysis showed that pIT also was significantly higher in the test group compared with the first and second control groups. Analyzing RFA values, only the difference between the test group and second control group showed statistical significance. Pearson correlation analysis showed a very strong positive correlation between pIT and VTW values in all groups; furthermore, it showed a positive correlation between pIT and RFA values and between VTW and RFA values only in the test group. Within the limitations of an in vitro study, the results show that stepped osteotomy can be a viable method to improve implant primary stability in low-density bone sites, and that, when a traditional osteotomy method is performed, RFA presents no correlation with pIT and VTW.

Comparison of Osteotome and Conventional Drilling Techniques for Primary Implant Stability: An In Vitro Study.

It may be difficult to achieve primary stability in the posterior maxilla because of poor quality and quantity of bone. Studies have shown that the osteotome technique immediately increases bone density thereby increasing primary stability. An in vitro study was conducted to compare the stability achieved by the osteotome and conventional drilling techniques in low density bone. Forty endosseous implant fixtures (n = 40) were inserted in a solid rigid polyurethane block simulating low density (D3) bone. The implants were divided into 4 groups to test 2 variables: (1) implant length (10 mm or 13 mm) and (2) preparation of osteotomy (conventional drilling or osteotome technique). Insertion torque (IT) and resonance frequency analysis (RFA) were measured for each implant. Statistical analysis using one-way ANOVA and Tukey post hoc test was done to study IT and RFA data of the 4 groups. Pearson Correlation test was used to determine the correlation between IT and RFA values of the implants. The IT and RFA values were statistically significant higher using the osteotome technique as compared to conventional drilling (P < 0.0001). Statistically significant higher values were also found for IT and RFA of 13 mm implants as compared to 10 mm implants. A significant correlation was found between insertion torque and RFA values in all 4 groups (r = 0.86, P < 0.0001). The conclusion was that the osteotome technique significantly increased primary stability.

Estudio experimental para establecer los valores de torque de inserción en implante dental&lt;br /&gt; Experimental study to establishing the insertion torque on dental implant

El principal proposito del trabajo de investigacion consistio en el desarrollo de un estudio para conocer los rangos de valores de torque de insercion del implante dental recomendados para reducir la probabilidad de generar sobrecarga patologica en densidades de tejido oseo de mandibula de la region molar. Se fabricaron implantes en Ti6Al4V para ser insertados en probetas de tejido oseo de cadaver de mandibula humana, asi como probetas de hueso sustituto Sawbone® normalizadas con densidades similares al hueso tipo densidad D2. Los implantes fueron insertados en las probetas registrando la medicion del torque de insercion. Los datos obtenidos en el ensayo fueron usados en simulaciones basadas en el metodo de elementos finitos. De este modo se pudo conocer los valores de torque cuyas deformaciones unitarias fueron inferiores al0.4% de la deformacion unitaria en la interfase hueso implante. A partir del caso de estudio, se recomendaron los valores de torque de insercion para ser aplicados en insercion de implantes en una cirugia.

Survivability of TiO2nanotubes on the surface of bone screws

Modifying surface chemistry and/or surface topography is considered to be a traditional way of optimizing bone-implant integration (osseointegration) for improved bone bonding. The previous results have shown enhanced in vitro osteoblast cell density on titania nanotube–covered surfaces compared with bare titanium surfaces. However, for titania nanotubes to be considered as a candidate surface modification for titanium implants, they must survive load-bearing conditions. The authors investigated the structural survivability of nanotubes on the surface of Ti-6Al-4V-ELI (extra low interstitials) cancellous bone screws subjected to insertion and removal using bone simulant. Measuring the torque during insertion in bone simulant was performed to provide input loads to a finite element model to predict the survivability of the titania nanotubes. Scanning electron microscopy was used to investigate the nanotube morphology before and after the insertion and removal tests. A finite element model using experimental insertion torque data estimated the maximum von-Mises stress in the titanium oxide nanotubes. The model predicted that the maximum von-Mises stress in the nanotubes due to combined compression and shear loading is well below the yield failure. Scanning electron microscopy observation confirmed the presence and survivability of the nanotubes after being subjected to multiple insertions and removals of the screws.

Impact of mini-implant length on stability at the initial healing period: a controlled clinical study

IntroductionAim of the study was to assess the impact of the length of mini-implants inserted in the midpalatal region on the stability at the initial healing period.MethodsA sample of 20 consecutively treated patients (15.6 ± 7.2 years) was examined. A long mini-implant with a length of 11 mm and a diameter of 2 mm was inserted into the anterior palate of each patient. Resonance frequency analysis (RFA) was performed after insertion (T0), two weeks (T1), four weeks (T2), and six weeks (T3). Insertion depth (ID) and the maximum insertion torque (IT) were measured. RFA, ID and IT data were tested for correlations. RFA values were tested for statistical differences between the different times. Data was compared to a matched control group of patients who received short mini-implants with a length of 9 mm and a diameter of 2 mm.ResultsMean ID was 9.5 ± 0.6 mm and mean IT was 17.9 ± 3.8 Ncm. A correlation was found between RFA and ID (r = 0.59, P < .01). From T0 to T1 the stability (33.4 ± 3.5 ISQ) decreased highly significantly by 5.3 ± 3.5 ISQ values (P < .001) and significantly from T1 and T2 (P < .05) by 3.5 ± 3.7 ISQ values. From T2 on RFA nearly remained unchanged (−1.7 ± 3.9 ISQ; P > .05). At T1 stability was significantly lower than the control group. From T2 on there were no significant differences between the groups.ConclusionsLong mini-implants provide high stability when inserted in the midpalatal region. After initial decrease RFA values remained stable from four weeks on and did not differ from the control group.Trial registrationID: 2013081293 (Clinical study register, University of Düsseldorf, Germany).

Effects of repeated sterilization cycles on primary stability of orthodontic mini-screws

To determine if repeated sterilization has deleterious effects on the clinical stability of mini-screws. Thirty each of the following mini-screws were tested: Aarhus (American Orthodontics, Sheboygan, Wisc), VectorTAS (Ormco Corporation, Orange, Calif), Dual-Top (RMO, Denver, Colo), and Ortho Anchor (KLS Martin, Jacksonville, Fla). Controls were sterilized once using a steam autoclave (Statim 5000, SciCan USA, Canonsburg, Pa). Each group of mini-screws was divided into three groups: the control (n = 10) and two test groups (n =10, each). Test groups were cycled five and 10 times respectively. All screws were inserted into custom-designed synthetic blocks that simulated mandibular bone. Maximum insertion torque and lateral displacement force data were recorded and subjected to statistical testing. Two-way analysis of variance (ANOVA) and three-way mixed ANOVA were used for statistical analyses for maximum insertion torque data and lateral displacement force data, respectively. Level of significance was established at P < .05. Insertion torque values displayed significant differences between both of the groups and sterilization cycles (P < .05). Significant differences were observed between American Aarhus mini-screws and both RMO and KLS Martin mini-screws. Ormco Vector mini-screws also differed significantly from the KLS Martin mini-screws in this comparison (P < .05). For lateral displacement, there was a significant main effect of groups, F(1,36) = 14.5 (P < .05). Significant differences were observed between American Aarhus mini-screws and all three of the other groups (P < .05). The examined groups displayed statistical differences of variable quality that may not affect their clinical stability.

Development of a New Implant Primary Stability Parameter: Insertion Torque Revisited

The aims of the study are to introduce a new parameter to measure primary stability and to evaluate the possible correlations between this parameter and bone density, initial bone-to-implant contact (IBIC), Resonance Frequency Analysis (RFA), and peak insertion torque (IT). The study was performed on three different types of fresh humid bovine bone: type I, type II, and type III. A total of 90 XiVE implants (30 per bone type) were used; implant insertion was performed with a calibrated maximum torque of 70 Ncm at predetermined 30 rpm. The IT data were recorded and exported as a curve; using a trapezoidal integration technique, the area underlying the curve was calculated: this area represents the variable torque work (VTW). Furthermore, peak IT and RFA were recorded; finally IBIC was calculated from histological specimens. Spearman correlation analysis of the entire sample reveals that VTW presents a significant (p < .01) positive correlation with bone density; a significant (p < .05) positive correlation with IBIC, and a significant (p < .01) positive correlation with all the other primary stability parameters. Spearman correlation analysis of the three different groups show that VTW presents a significant positive correlation with IT in all three types of bone; on the other hand, VTW shows a negative not significant correlation with RFA in bone I, a positive significant correlation in bone II, and a positive not significant correlation in bone III. Furthermore, VTW shows a negative significant correlation with IBIC in bone I and a positive significant correlation in bone II and III. Within the limitations of an in vitro study, the VTW seems to be a promising parameter to measure implant primary stability.

Implant micromotion is related to peak insertion torque and bone density

Measuring peak insertion torque in relation to different bone densities, the present study seeks to determine whether micromotion at the interface is related to primary stability achieved by increasing insertion torque. A total of 120 Ti-Bone implants were placed in fresh bovine bone samples representing three density categories: hard, normal and soft (HNS). Five groups of peak insertion torque (20, 35, 45, 70 and 100 N/cm) were evaluated in the three bone density categories noted. Customized electronic equipment connected to a PC was used to register the peak and other insertion torque data. A loading device, consisting of a digital force gauge and a digital micrometer, was used to measure the micromovements of the implant during the application of 20, 25 and 30 N lateral forces. The data were analyzed for statistical significance by ANOVA and Spearman's rank correlation coefficient tests. A statistically significant difference between implant micromobility placed with different levels of torque and in different bone densities was demonstrated by ANOVA. Spearman's rank correlation coefficient showed a high dependency between the peak insertion torque and the observed micromovement. Particularly, in soft bone, it was not possible to achieve more than 35 N/cm of peak insertion torque. Results showed that increasing the peak insertion torque reduces the level of implant micromotion. In addition, micromotion in soft bone was found to be consistently high, which could lead to the failure of osseointegration. Thus, immediate functional loading of implants in soft bone should be considered with caution.

Two Alternative Surgical Techniques for Enhancing Primary Implant Stability in the Posterior Maxilla: A Clinical Study Including Bone Density, Insertion Torque, and Resonance Frequency Analysis Data

The primary stability of dental implants associated with resistance to micromotion during healing is affected by surgical technique and implant design, which are important especially in the soft bone, where implant failures are more likely. This study was designed to compare the parameters associated with implant insertion using two different methods of enhancing implant primary stability and to identify any relationship between these parameters at implant insertion. A total of 60 implants were placed in the maxillary posterior regions of 22 patients. The bone densities at the implant sites were recorded using a computerized tomography machine in Hounsfield unit (HU). The maximum insertion torque data were recorded with the Osseocare (Nobel Biocare AB, Göteborg, Sweden) equipment, while resonance frequency analysis (RFA) measurements were taken using an Osstell (Integration Diagnostics AB, Göteborg, Sweden) machine at implant surgery. Comparisons including HU, Ncm, and implant stability quotient were made between two control groups (C1 and C2), and corresponding four test groups (T1-T4) using thinner drills to enhance primary implant stability. Two implants were lost, meaning an overall implant survival rate of 96.6% after 3 +/- 1 years. When compared to control groups, significantly higher mean maximum insertion torque and RFA values were found for corresponding test groups. In addition, strong correlations were observed between the bone density and insertion torque, and implant stability values at implant placement. The results of this study suggest that using thinner drills for implant placement in the maxillary posterior region where bone quality is poor may improve the primary implant stability, which helps clinicians to obtain higher implant survival rates.

A Comparison of Two Methods of Enhancing Implant Primary Stability

Surgical technique and implant design have an effect on the primary stability of oral implants, which in turn increases resistance to implant micromotion during healing. This study was designed to compare the parameters associated with implant insertion using two different methods of enhancing implant primary stability and to identify any relationship between these parameters and changes in the stability of implants during the initial 6-month healing period following implant insertion. A comparison was made between two methods of enhancing primary implant stability: method 1, standard Brånemark System implants (Nobel Biocare AB, Gothenburg, Sweden) inserted with a technique designed to enhance primary stability, and method 2: Brånemark Mk IV implants (Nobel Biocare AB) inserted according to the manufacturer's instructions. Thirteen patients were selected for inclusion in the study. A total of 42 implants were placed. Insertion torque data were recorded, and bone quality at the implant site was assessed at implant insertion. Resonance frequency analysis measurements were taken at implant insertion as well as at second-stage surgery 6 months later. A statistically significant difference was recorded between the mean maximum insertion torque for type 4 bone and bone types 2 and 3. No significant difference was recorded between bone types 2 and 3. A significantly lower resonance frequency value was seen for standard implants placed into type 4 bone (p < .05). Across all implant types a significant difference in the energy required when inserting implants into type 4 bone and bone types 2 and 3 was seen. A significantly lower mean energy requirement was seen between the Mk IV implants placed into type 4 bone and the other combinations of implant types and bone. Within the limitations of this study, the results agree with the manufacturer's claim that when compared with standard implants, the design of the Mk IV implant increases implant primary stability with a reduction in the energy imparted into the bone at the implant site.

Experimental investigation of threaded cup performance during insertion in total hip replacement.

Cementless threaded cups are often used in Europe on the acetabular side of a total hip arthroplasty (THA), with some products achieving excellent clinical results. Titanium and titanium alloys are nowadays accepted as the materials of choice for these implants. In contrast, however, there is no consensus about the ideal thread design. This in vitro and human cadaver study aimed to compare the insertion torques of commercially available threaded cups during insertion. The aims were (1) to see whether the clinical experience of surgeons using these cups specifically related to insertion torque could be reproduced in the experiment and (2) to assess whether or not the cup size and thread design has a statistically significant influence on the insertion torque. Using a biaxial testing machine the cups were screwed into pre-machined polyurethane blocks and the insertion torque was recorded by an appropriate sensor. Clear differences were seen between the four different designs. A variance analysis using statistical software showed that both the cup size (p=0.003) and the thread design (p=0.0009) significantly affect the insertion torque. The human cadaver study allowing a right-left comparison of two different cups within the same specimen confirmed the insertion torque data of the experimental study. In addition, the trends observed during the course of the insertion agreed with the clinical experience of the orthopaedic surgeons consulted as part of this study. (Hip International 2004; 14: 11-7).

Experimental investigation of threaded cup performance during insertion in total hip replacement

Cementless threaded cups are often used in Europe on the acetabular side of a total hip arthroplasty (THA), with some products achieving excellent clinical results. Titanium and titanium alloys are nowadays accepted as the materials of choice for these implants. In contrast, however, there is no consensus about the ideal thread design. This in vitro and human cadaver study aimed to compare the insertion torques of commercially available threaded cups during insertion. The aims were (1) to see whether the clinical experience of surgeons using these cups specifically related to insertion torque could be reproduced in the experiment and (2) to assess whether or not the cup size and thread design has a statistically significant influence on the insertion torque. Using a biaxial testing machine the cups were screwed into pre-machined polyurethane blocks and the insertion torque was recorded by an appropriate sensor. Clear differences were seen between the four different designs. A variance analysis using statistical software showed that both the cup size (p=0.003) and the thread design (p=0.0009) significantly affect the insertion torque. The human cadaver study allowing a right-left comparison of two different cups within the same specimen confirmed the insertion torque data of the experimental study. In addition, the trends observed during the course of the insertion agreed with the clinical experience of the orthopaedic surgeons consulted as part of this study. (Hip International 2004; 14: 11-7).