Initial Implant Stability Quotient Research Articles

Implant Stability and Histomorphometric Analysis Comparing Two Different Implant Macrogeometries Placed in Fresh Sockets: An Experimental Study in Sheep.

The aim of the present animal study was to examine the impact of two implant designs that promote different insertion torque values on implant stability and evaluate, histomorphometrically, the bone healing for immediate implant placement in fresh sockets. Twelve female sheep (35.0±5.0kg) and 48 conical Morse-taper dental implants divided into two groups (n = 24 per group): G1 group, where the implants present a design that can provide high insertion torque values; and G2 group, where the implants present a design that can provide low insertion torque values. Both had the same surface treatment, and dimensions (4.0 mm in diameter and 10 mm in length). The first two posterior teeth (both sides) were extracted carefully. Sequentially, there were osteotomies in the mesial socket of each molar tooth. The final implant position was 2 mm below the buccal bone crest level. On the right side, implants of the G1 were placed anteriorly, followed by implants of the G2; and, on the left side, it was the reverse. A digital torquemeter was used to measure the maximum final insertion torque value (f-IT). The initial implant stability quotient (ISQ) was measured immediately after the implant insertion (T0) and immediately after the euthanasia and removing the mandibles with the implants. The animals were euthanized (n=6 animals/ time) at 21 days (T1) and 35 days (T2). The t-test was used to compare statistical differences for each intragroup parameter analyzed. Pearson's correlation was used to analyze possible correlations: f-IT and BIC%, f-IT and ISQ, and ISQ and %BIC. Regarding the insertion torque, the G1 presented higher values than the G2, with a statistically significant difference (p<0.0001). The ISQ mean values were higher in the B-L direction than those obtained for M-D for both groups. %BIC measurements showed higher values in samples from G2 than G1 at both times and in both directions. New bone, medullary spaces, and collagen matrix had statistical differences between the groups at each evaluation time. Using implants with a modified macrogeometry plays a significant role in implant stability and the healing process of bone tissue around the implant. It is important for clinicians to carefully consider implant macrogeometry when planning dental implant surgery to achieve optimal implant stability and successful osseointegration, mainly in cases of immediate implant placement.

Effect of the Magnetic Field Generated by a New NeFeB Cover Screw on Bone Healing around Endosseous Implants: A Case Series Report from Dental Practice

This study aimed to investigate the effect of static magnetic field (SMF) generated by innovative cover screws made of NeFeB on early bone healing around dental implants. The study was carried out on humans in a private dental practice. Eight 3i implants (Biomet, Palm Beach, FL, USA) were placed in the posterior mandible at 3.6 and 3.7. The control implants were closed with a conventional screw (G1), while the test implants were closed with a Supercharged® screw (G2). Both groups were compared for stability at 0, 7, 14, 21, 50, and 90 days using a resonant frequency analyzer with Ostell Mentor (Osstell AB, Gothenburg, Sweden). After 50 days, the Supercharged® cover screw was removed. A significant increase in implant stability quotient (ISQ), corresponding to a lower degree of bone resorption, was observed in G2 throughout the follow-up period (p &lt; 0.05), while an initial ISQ decrease was observed until day 21 in G1. In conclusion, the effect of SMF seems to be in the early stages of osseointegration and increases the stability of dental implants.

Biomechanical and histological evaluation of four different implant macrogeometries in the early osseointegration process: An in vivo animal study

This study aims to evaluate the effects of implant macrogeometry on the early period of the osseointegration process, comparing four different implant models through biomechanical and histological analysis after implantation in rabbit tibiae. Twenty New Zealand rabbits were used, evaluated at two different times (21 and 28 days) after installation of the implant. Eighty implants with different macrogeometries were used, forming four groups (n = 20 per group): cylindrical implants Ø4.1 mm and 8 mm in length (STRc group); cylindrical–conical implants Ø4.1 mm and 8 mm in length (STRt group); tapered implants Ø4.3 mm and 8 mm in length (NOBt group); and tapered implants with healing chambers Ø4.0 mm and 8 mm in length (MAEt group). Ten samples from each group were analyzed at each proposed time. The initial implant stability quotient (ISQ) was measured by resonance frequency analysis, both at the time of installation and at the time of sacrifice. In the histological sections, the percentage of bone–implant contact (BIC%), newly formed bone, osteoid matrix, and medullary spaces were measured in the pre-determined cortical and medullary bone portion for each sample. The three tapered implant groups (STRt, NOBt, and MAEt) showed higher values for the analyzed parameters in the early osseointegration period, in comparison with the cylindrical implant group (STRc). In all parameters, the three tapered groups showed no difference (p > 0.05); however, all three tapered groups presented significant differences, when compared to the cylindrical group (p < 0.05). No correlation was detected between the parameters analyzed. Within the limitations of the present study, in all parameters analyzed, the tapered implants demonstrated greater results when compared to the cylindrical implants.

Role of New Hydrophilic Surfaces on Early Success Rate and Implant Stability: 1-Year Post-loading Results of a Multicenter, Split-Mouth, Randomized Controlled Trial.

Objective To compare early implant failure and implant stability of one-stage Hiossen ET III implants with its new hydrophilic (NH) surface, compared with Hiossen ET III implants with the sandblasted and acid-etched (SA) surface at 1-year follow-up. Materials and Methods This study was designed as a split-mouth, multicenter randomized controlled trial aimed to compare SA surface implants (SA group) and NH surface, (NH group). Outcomes were implant and prosthetic survival rates, complications, the insertion torque at implant placement, and implant stability quotient (ISQ) values. Results Twenty-nine patients (mean age 59.9 ± 11.3 years) were treated and followed up to 1 year after loading. No patient dropped out. Fifty-eight implants (29 SA group and 29 NH group) were placed. No implants or prostheses failed and no complications were experienced during follow-up. The mean insertion torque was 40.5 ± 3.23 (38.17–41.83) Ncm in the SA group and 40.48 ± 3.49 (38.02–41.98) Ncm in the NH group ( p = 0.981). There was a statistically significant difference at the second week (T2) with higher values in the NH group ( p = 0.041). Similar results were found in the maxilla ( p = 0.045), but not in the mandible ( p = 0.362). A positive correlation was found between initial insertion torque and ISQ with higher value in the NH group (0.73 vs. 0.66). Conclusions NH implants are a viable alternative to SA surface, as they seem to avoid the ISQ drop during the bone remodeling phase.

Resonance Frequency Analysis in Assessing Implant Stability: A Retrospective Analysis.

To retrospectively assess implant stability quotient (ISQ) values in patients who were followed up between 1998 and 2014 and to evaluate any correlations between ISQ and clinical parameters, such as change in marginal bone level (MBL). A total of 173 participants (65 men and 108 women; age range 21 to 85 years) and 383 implants were included. Implant location, MBL, and ISQ were recorded at surgery and at various recall times for statistical analysis. Mixed-model analysis was applied to evaluate the impact of clinical and demographic variables (time, implant location, patient gender) on ISQ and the correlation between ISQ and MBL. The level of significance was set at P < .05. Of the 21 failed implants, 20 failed within 1 year of functional loading, resulting in a 10-year cumulative implant survival estimate of 95%. The failed implants had lower ISQs at surgery (52.3 ± 7.03) and baseline (52.5 ± 4.20) when compared to surviving implants (63.0 ± 10.74 at surgery and 62.3 ± 8.30 at baseline), and the difference was statistically significant at surgery (P < .05). The mean ISQs generally increased over time, but there were various patterns of changes between implants when grouped according to patient gender and implant location. There was no statistically significant correlation between the changes in ISQ and MBL (P = .211), despite an inverse relationship. Low initial ISQ values may help to identify implants at higher risk of failure. There may be various patterns of change over time in addition to an overall increase in ISQ values. Both similar and contradictory findings were found when compared to earlier literature, and a correlation between resonance frequency analysis and MBL change could not be identified. Despite limitations, the present study provides an overview of the clinical performance of RFA based on long-term clinical data.

Influence of time on primary stability of dental implants placed with osteotomes due to the elastic properties of peri-implant bone

Background/purposeThe use of osteotomes as a technique for densification and expansion of the residual ridge is one of the most widely used procedures to achieve adequate peri-implant bone quantity and density. The aim of this study was to evaluate the influence of time and the elastic deformation of peri-implant bone in the primary stability of implants placed using osteotomes. Materials and methodsIn each of 10 fresh fragments of cow rib, two implants were placed using osteotomes. The insertion torque and initial implant stability quotient (ISQ) values were measured. In the control implants, the immediate removal torque was measured, while in the test implants, after 15 min of placement, ISQ values were measured again, and the removal torque was measured. ResultsThere were significant differences between the ISQ values and between the insertion torque and removal torque at 15 min. The ISQ values (perpendicular/parallel) increased between the initial moment (64.4 ± 9/70.3 ± 5.9) and 15 min (66/71.4 ± 6.4). The removal torque at 15 min (12.4 ± 5.8) was lower than the insertion torque (15.9 ± 5.9). Compression of the trabeculae in contact with the implant placed using osteotomes was observed, as well as a greater number of trabecular fractures in the implants placed using conventional drilling. ConclusionThere is an increase in ISQ values of dental implants placed using osteotomes after 15 min of placement.

Does implant site preparation technique affect ISQ trends, bone loss for varying implant lengths?

Background Bone expansion has been used for implant site preparation in the posterior maxilla as it involves compression of trabecular bone thereby enhancing bone-to-implant contact and primary implant stability. This study used a split mouth design to compare conventional drilling and bone expansion techniques by evaluating the ISQ trends upto implant loading and progressive crestal bone loss. It also analyzed the effect of these techniques when implants of different lengths were used. Aim/Hypothesis (a) Which of the 2 site preparation techniques-Conventional drilling or bone expansion showed favorable initial and progressive ISQ trends and minimal bone loss. (b) Which of the above mentioned techniques performed better when implants of different length were placed. Material and Methods 30 patients who required replacement of a single tooth bilaterally in the posterior maxilla were recruited. In all, 60 implant sites were assessed for bone density by undergoing Cone Beam Computed tomography. Using random allocation, each patient received an implant using drilling protocol (Control site) on one side and using expansion technique on the contralateral side (Test site). The implants placed in the Control and Test site were of the same brand, length and diameter. After a load free healing period of 3 months, the implants were restored using screw retained porcelain-fused to metal restorations. The following parameters were evaluated- (a) Implant Stability Quotient (ISQ) values -ISQ at implant placement (ISQi) and at commencement of functional loading (ISQf) was recorded using Osstell ISQ. (b) Crestal bone loss. - Periapical radiographs were taken immediately after implant placement and at the time of placement of the definitive restoration. Results A highly statistically significant difference was noted between the Test and the Control group when ISQi , ISQf and Crestal bone loss were compared. For implants of length > 10 mm, the Test group presented with statistically significant higher mean ISQi & ISQf (59.76 ± 4.33 & 62.56 ± 4.08) values in comparison to Control group (55.46 ± 3.66 & 58.60 ± 4.01). A statistically significant higher mean crestal bone loss was noted in the Control group (−0.37 mm ± 0.09 mm) as compared to the Test group (−0.19 mm ± .06 mm). For implants <10 mm in length, a higher (not significant) mean ISQi & ISQf (62.23 ± 2.38 & 65.60 ± 2.72 ) values were noted for the Test group in comparison to Control group (60.56 ± 4.12 & 64.05 ± 4.01). A higher (not significant) mean crestal bone loss was noted in the Test group (−0.32 mm ± 0.09 mm) as compared to Control group (−0.30 mm ± 0.14 mm). Conclusions and Clinical Implications The bone expansion technique resulted in higher initial and final ISQ values, lesser bone loss compared to the conventional drilling technique in the posterior maxilla. When implants longer than 10 mm were used, bone expansion technique showed a more favorable ISQ trends and reduced bone loss.

Improvement in the Initial Implant Stability Quotient Through Use of a Modified Surgical Technique.

To ensure similar primary implant stability measured by resonance frequency analysis (RFA) could be obtained in different jawbone densities by using a specific surgical drilling protocol and, to correlate those RFA measurements with factors related to the implant design, width, and length, we are performed a 1-year prospective clinical study was carried out using 27 subjects. A total of 67 hydrophilic titanium implants were placed using a standard 2-stage implant placement protocol. The bone type at each implant site was determined by evaluation of a preoperative, high-resolution cone beam computerized tomography (CBCT) scan. A modified drilling protocol was used in softer bone (types 2, 3, and 4) that allowed for greater implant thread contact with the surrounding bone. The implant stability quotient (ISQ) was measured at 4 different times during the study: initially it was determined immediately after implant placement, then again at stage 2 uncovering surgery, then at 6 months' postplacement and, and finally at 1 year postplacement. Data collected immediately after implant surgery demonstrated a high correlation (R2 = .99) between the ISQ and bone type classification. An overall trend toward a higher ISQ was found over the 1-year study period for all types of bone. Implants remained clinically and radiographically stable during the 1-year study period. Our data allow conclude that the primary stability of 2-staged loaded implants placed in different bone types can be optimized by applying this surgical drilling protocol during the implant placement. The ISQ method was found to be a reliable predictor of implant stability.

The effect of implant macro-thread design on implant stability in the early post-operative period: a randomized, controlled pilot study.

Available literature suggests there is a transient drop in implant stability from approximately week 0 to week 3-4 as a result of peri-implant bone remodeling as it transitions from a primary, mechanical stability to a secondary, biological stability. Research investigating the influence of macro-thread design on this process is scant. The specific aim of this study was to evaluate the role of macro-thread design on implant stability in the early post-operative healing period using resonance frequency analysis (RFA). Seven patients, each missing at least two posterior teeth in the same arch, were included in the study. Three patients qualified for four implants resulting in a total of 10 matched pairs. All sites were healed (>6months), non-grafted sites with sufficient bone to place implants. Each site in a matched pair was randomly assigned to receive either a control (Megagen EZ Plus Internal; EZ) or test (Megagen AnyRidge; AR) implant. The test implant incorporates a novel thread design with a wide thread depth and increased thread pitch. RFA was used to determine implant stability quotient (ISQ) values for each implant at the time of placement and weekly for the first 8weeks. Implants consistently achieved a relatively high insertion torque (30-45N/cm) and high initial ISQ value (79.8±1.49). Baseline ISQ values for test (AR; 79.55±1.61) and control (EZ; 80.05±1.37) implants were similar. A general pattern of stability from baseline through all eight follow-up evaluations was observed for the test implants. A pattern of decreasing ISQ values was observed for the control implants across the early follow-up evaluations up to week four, where the value plateaued. There was a statistically significant main effect due to implant type (P<0.01) and a statistically significant interaction between implant type and time (P<0.01), indicating that the test and control implants performed differently at certain time points. Within the limitations of this study, macro-thread design appears to play a role in implant stability in the early post-operative healing period as assessed by RFA. These findings may have important implications related to immediate or early loading protocols.

Bone Response and Soft Tissue Changes Around Implants With/Without Abutments Supporting Fixed Partial Dentures: Results From a 3-Year, Prospective, Randomized, Controlled Study.

Diverging opinions exist regarding rough surface abutment usage, and abutment exclusion effects are unstudied. The study aims to: (1) assess tissue response to oxidized or machined abutments or no abutment; and (2) evaluate immediate implant-loading effects. In a 2005-2008 parallel-group randomized, clinical trial, 50 partially edentulous subjects received three Brånemark TiUnite™ (Nobel Biocare®, Gothenburg, Sweden) implants. Superstructures were attached via abutments (one with a TiUnite surface - AOX, and one with a machine-milled surface - AM) or directly at implant level (IL). Implants were immediately loaded (test) or unloaded for 3 months (control). Postoperative examinations were done up to 3 years. Forty-seven subjects were reexamined after 3 years. Four and two implants were lost in test and control groups, respectively, during the first year. Thereafter, no implant loss occurred (95.7% survival). After 1 year, mean (SEM) peri-implant marginal bone loss (MBL) was 1.33 (0.08) mm (test) and 1.25 (0.08) mm (control). Between 1 and 3 years, a nonsignificant MBL occurred: 0.36 (0.08) mm (test) and 0.33 (0.06) mm (control). Similar MBL was found at IL (1.81 [0.93] mm) and AOX (1.77 [0.14] mm) after 3 years and was significantly lower at AM (1.42 [0.17] mm) than at IL (groups merged); 42% of the implants displayed mucosal bleeding at 3 years and probing pocket depths varied between 2.13 (0.12) mm and 3.62 (0.15) mm, significantly lower buccally. Bleeding on probing (BoP) in minute amounts was found in 30-45% of the sites and abundant BoP at about 20% of the sites. Soft tissue retracted mostly during year 1 and was more pronounced buccally. Regression analyses revealed significant effects from smoking, periodontal disease, abundant BoP, and a low initial implant stability quotient on MBL. No further significant MBL was found between 1 and 3 years, irrespective of loading protocol. Use of machined abutments may benefit marginal bone stability over time.

Implant Stability Change and Osseointegration Speed of Immediately Loaded Photofunctionalized Implants

This study evaluated the degree and rate of implant stability development for photofunctionalized dental implants in humans. Thirty-three implants (7 patients) placed in the maxilla and immediate loaded were evaluated. Photofunctionalization was performed by treating implants with ultraviolet for 15 minutes immediately before placement. Implant stability was assessed by measuring the implant stability quotient (ISQ) weekly starting from implant placement up to 3 months. Osseointegration speed index (OSI), defined as ISQ increase per month, was also evaluated. The average ISQ for photofunctionalized implants at week 6 was 78.0, which was considerably higher than the average ISQ of 66.1, reported in literature for various as-received implants after a longer healing time of 2 to 6 months. No stability dip was observed for photofunctionalized implants regardless of the initial ISQ values. The OSI for photofunctionalized implants was 6.3 and 3.1 when their initial ISQ was 65 to 70 and 71 to 75, respectively, whereas the OSI values for as-received implants calculated from literature ranged from -3.0 to 1.17 with an average of -0.10. Photofunctionalization accelerated and enhanced osseointegration of dental implants, providing novel and practical avenues for further advancement in implant therapy.

Photofunctionalized Dental Implants: A Case Series in Compromised Bone

Ultraviolet (UV) light treatment of titanium, or photofunctionalization, has been shown to enhance its osteoconductivity in animal and in vitro studies, but its clinical performance has yet to be reported. This clinical case series sought to examine the effect of photofunctionalization on implant success, healing time, osseointegration speed, and peri-implant marginal bone level changes at 1 year after restoration. Four partially edentulous patients were included in the study. Seven implants with identical microroughened surfaces were photofunctionalized with UV light for 15 minutes. Osseointegration speed was calculated by measuring the increase in implant stability quotient (ISQ) per month. Marginal bone levels were evaluated radiographically at crown placement and at 1 year. All implants placed into fresh extraction sockets, vertically augmented bone, simultaneously augmented sinuses, or the site of a failing implant remained functional and healthy at 1 year, even with an earlier loading protocol (2.1 to 4.5 months). ISQs of 48 to 75 at implant placement had increased to 68 to 81 at loading. In particular, implants with low primary stability (initial ISQ < 70) showed large increases in ISQ. The speed of osseointegration of photofunctionalized implants was considerably greater than that of as-received implants documented in the literature. Mean marginal bone levels were -0.35 ± 0.71 mm at crown placement and had significantly increased to 0.16 ± 0.53 mm at 1 year, with coronal gains in marginal bone level that surpassed the implant platform. No implants showed marginal bone loss. Within the limits of this study, photofunctionalization expedited and enhanced osseointegration of commercial dental implants in various clinically challenging/compromised bone conditions. Photofunctionalization resulted in preservation--and often a gain--of marginal bone level, and long-term large-scale clinical validation is warranted.

Bone tissue microarchitectural characteristics at dental implant sites part 2: correlation with bone classification and primary stability

To investigate in vivo the correlation between the bone microarchitecture of implant bone sites, bone tissue classification subjectively assessed in radiographs and primary implant stability. Periapical and panoramic radiographs were obtained from 32 partially edentulous patients. Three surgeons classified bone quality at implant sites using two different methods: assessments in periapical and panoramic radiographs (PP) and according to the classification proposed by Lekholm and Zarb (L&Z). During the implant insertion, bone biopsies were taken, and three-dimensional parameters were measured by microcomputed tomography (microCT). Insertion torque value (ITV) and initial implant stability quotient (ISQ) were recorded at the moment of the implantation. ISQ was also recorded at the uncovering stage of a traditional implant protocol. Bone types 2 and 3 were the most prevalent classifications according to PP (54.3%) and L&Z (58.7%). The mean and standard deviation values of primary stability variables were 38.7(16.7) for ITV, 75.3 (7.7) for initial ISQ and 79.3 (6.8) for uncovering ISQ. Several microCT original and factor variables were found to correlate with bone tissue classifications and primary stability variables. L&Z correlated with architecture (r = 0.31; P < 0.05), density (r = -0.43; P < 0.01) and bulk (r = -0.35; P < 0.05), whereas ITV correlated with architecture (r = -0.40; P < 0.01) and density (r = 0.51; P < 0.01). Multiple linear regression analysis revealed that density and bulk explained 32% of the variability of L&Z bone classification, while density and architecture explained 42% of the variability of ITV. This study demonstrates the first step in validating L&Z classification. MicroCT provides objective and detailed quantitative data on bone microarchitecture. Intraosseous implant stability is mainly determined by the density of the bone. ITVs could be a good indicator of primary implant stability, whereas ISQs measurements have some limitations and should not be used alone.

Relation between initial implant stability quotient and bone-implant contact percentage: an in vitro model study

This study evaluated the correlation between the initial stability of a dental implant, quantified as the implant stability quotient (ISQ), and the bone-implant contact percentage ( BIC%). Dental implants were inserted into specimens comprising an artificial cortical shell representing cortical bone and foam bone representing cancellous bone with 4 elastic moduli. Each specimen with an implant was subjected to microcomputed tomography (micro-CT) scanning, from which the 2D and 3D BIC% values were calculated. The values of the Spearman correlation coefficient (r) were calculated between the ISQ and the 2D and 3D BIC% values. Increasing the elasticity of the specimen enhanced the ISQ. There was statistically significant correlation between the ISQ and 3D BIC% values (r = 0.85, P < .0001). However, the correlation between ISQ and 2D BIC% values was not statistically significance (r = 0.42, P = .062). The initial implant stability was strongly positively correlated with the 3D BIC%.

Effects of the 3D bone-to-implant contact and bone stiffness on the initial stability of a dental implant: micro-CT and resonance frequency analyses

This study investigated the effects of bone stiffness (elastic modulus) and three-dimensional (3D) bone-to-implant contact ratio (BIC%) on the primary stabilities of dental implants using micro-computed tomography (micro-CT) and resonance frequency analyses. Artificial sawbone models with five values of elastic modulus (137, 123, 47.5, 22, and 12.4MPa) comprising two types of trabecular structure (solid-rigid and cellular-rigid) were investigated for initial implant stability quotient (ISQ), measured using the wireless Osstell resonance frequency analyzer. Bone specimens were attached to 2mm fibre-filled epoxy sheets mimicking the cortical shell. ISQ was measured after placing a dental implant into the bone specimen. Each bone specimen with an implant was subjected to micro-CT scanning to calculate the 3D BIC% values. The similarity of the cellular type of artificial bone to the trabecular structure might make it more appropriate for obtaining accurate values of primary implant stability than solid-bone blocks. For the cellular-rigid bone models, the ISQ increased with the elastic modulus of cancellous bone. The regression correlation coefficient was 0.96 for correlations of the ISQ with the elasticity of cancellous bone and with the 3D BIC%. The initial implant stability was moderately positively correlated with the elasticity of cancellous bone and with the 3D BIC%.

Stability of dental implants after irradiation with an 830-nm low-level laser: a double-blind randomized clinical study

Little is known about the benefits of low-level laser therapy (LLLT) on improvement of stability of dental implants. The aim of this randomized clinical study was to assess the LLLT effect on implants stability by means of resonance frequency analysis (RFA). Thirty implants were distributed bilaterally in the posterior mandible of eight patients. At the experimental side, the implants were submitted to LLLT (830 nm, 86 mW, 92.1 J/cm(2), 0.25 J, 3 s/point, at 20 points), and on the control side, the irradiation was simulated (placebo). The first irradiation was performed in the immediate postoperative period, and it was repeated every 48 h in the first 14 days. The initial implant stability quotient (ISQ) of the implants was measured by means of RFA. New ISQ measurements were made after 10 days, 3, 6, 9, and 12 weeks. The initial ISQ values ranged from 65-84, with a mean of 76, undergoing a significant drop in stability from the 10th day to the 6th week in the irradiated group, and presenting a gradual increase from the 6th to the 12th week. The highest ISQ values were observed on the 10th day in the irradiated group, and the lowest in the 6th week in both groups. Under the conditions of this study, no evidence was found of any effect of LLLT on the stability of the implants when measured by RFA. Since high primary stability and good bone quality are of major relevancy for a rigid bone-implant interface, additional LLLT may have little impact macroscopically.

Assessing Double Acid-Etched Implants Submitted to Orthodontic Forces and Used as Prosthetic Anchorages in Partially Edentulous Patients

:The use of implants as anchorage for orthodontic forces seems to be a good alternative in partially edentulous patients needing orthodontic treatment. This study is aimed at assessing the performance and behavior of microtextured surface endosseous implants obtained by means of a double acid etching against orthodontic forces, as well as their adequacy to be used first as anchorage and later as fixtures for the definitive prosthesis.Materials and Methods: A total of 93 double acid-etched surface parallel wall implants (Osseotite® Implants, Implant Innovations Inc., Palm Beach, Florida, USA) were inserted in 38 partially edentulous patients prior to orthodontic treatment This was carried out by following two-stage surgery protocols in the maxilla as well as in the mandible.After a healing period of six months for the maxilla and four months for the mandible, the implants were used as anchorage for sliding, compression and traction orthodontic forces between 100 to 200 g by means of Ni-TI springs.Bone level and Resonance Frequency Analysis (RFA) were measured before and after the introduction of the orthodontics forces.Results: After removal of the orthodontics appliances, all the implants remained stabile and served as support for prosthetic replacement of missing teeth. The bone level showed no variationeven when a positive difference 0.02 ± 0.38mm was noticed. The RFA scored a significant difference (p≤ 0.03) between the initial Implant Stability Quotient (ISQ) values (66) and the final ones (68).Conclusions: These findings showed that Osseotite implants were able to support the orthodontic forces applied during this investigation, maintaining osseointegration without significant variation in bone level. Therefore, they can be used to support dental prosthesis once they have been used as orthodontic anchorage under the cited conditions.

Resonance Frequency Analysis of One‐ Stage Dental Implant Stability During the Osseointegration Period

Currently, there is no available clinical tool to evaluate the amount of osseointegration and stability around dental implants. It has been recently suggested that changes in the stiffness of an implant in bone during healing may be monitored by using resonance frequency analysis (RFA). The aim of this study was to determine whether RFA can be integrated into the routine clinical evaluation of initial healing of dental implants. Thirty-one patients (18 female and 13 male; mean age of 51.7 years) were included into this study. A total of 122 implants and three different, but comparable, implant designs were evaluated by using RFA. The specific transducer for each implant system was used. ISQ (implant stability quotient) readings were obtained for each implant at the time of surgery, 3 and 6 weeks postoperatively, and at the time of loading (3 or 6 months following surgery). Data were analyzed for different healing times, various anatomical locations, implant length, and type. Average time in function was 12 months. Two implants failed during healing. Implant stability was higher on the mandible compared to the maxilla for each implant system studied (Mann-Whitney test, P <0.01). ISQ readings decreased significantly at 3 and 6 weeks post-surgery compared to readings obtained at surgery (Wilcoxon matched pairs sign-rank tests, P <0.01). A recovery to the initial ISQ levels was noted at the time of implant loading. The possible effects of different types and lengths of implants to ISQ readings were examined. Results of this study support the need for a clinical tool to evaluate dental implant stability prior to loading, especially for implants placed in the maxilla. It appears that implant stability is weakest at 3 to 6 weeks in one-stage non-loaded dental implants. ISQ readings can be used to determine different healing phases and the stability of dental implants. However, it is difficult to define a general standardized range of ISQ readings for successful implant integration for various implant systems. Thus, RFA values/ISQ levels should be calibrated for each implant system separately. Further studies are needed to compare the early changes seen in immediately loaded dental implants and to determine whether there is any time in which the total recovery in ISQ levels may occur.