Measurements of Implant Stability Following Sinus Lift: A Pilot Clinical Study

Aim

The aim of this study was to evaluate the implant stability of Bredent Sky Blue implants of different diameters following one stage sinus lift procedure.

Material and methods

This study included 9 male patients with an existing indication for unilateral or bilateral sinus lift procedure. As grafting materials, combination of allograft material MinerOss® cortical & cancellous and Ossceram nano were used.

Results

All implants were considered successful and ISQ levels were measured by Osstell ISQ device. The ISQ values were from 68 to 84. The mean values of stability of Bredent Sky Blue implants of different diameters following one stage sinus lift procedure were 77.73 ± 2.93 (MD) and 77.98 ± 2.72 (VO).Key words: dental implants, implant stability, sinus floor augmentation     

Long-term outcome of dental implants after maxillary augmentation with and without bone grafting

Background

This study aims to evaluate the technique of sinus bone reformation, which consists of elevating the sinus membrane and placement the implant without bone graft, compared with the widely-used technique involving raising the maxillary sinus and grafting, using animal hydroxyapatite as the filler, while simultaneously fixing the implants.

Material and Methods

This is a retrospective study on two groups of patients who underwent elevation of the sinus membrane and simultaneous placement of the implant. The grafting technique was applied to one group, while the other had no graft. An alveolar ridge height of 4 to 7 mm was necessary. Radiological control was undertaken at 6 months and one year post-prosthetic loading. In each group 38 implants were placed.

Results

No significant behavioural differences were observed in the implants according to the Albrektsson success criteria. Implant failure was observed in 2 implants from the bone grafting group (success rate 93%) and in 1 implant from the reformation group (success rate 97%). In this group, bone formation was observed on both sides of each implant, the bone gain was measured using image management software (2.7±0.9mm mesial and 2.6±0.9mm distal). There was no correlation between mesial and distal bone gain and implant´s length.

Conclusions

The results indicate that bone reformation is a valid technique in cases involving atrophy of the posterior maxilla. Primary stability, maintenance of space by the implant, and the formation of a blood clot are crucial in this technique in order to achieve bone formation around the implant. It is an alternative to the conventional technique of sinus lift with filling material, and has several advantages over this procedure, including a lower infection risk, as it does not involve a biomaterial, reduced cost, a simpler technique, and better acceptance by the patient. Key words:Bone formation, sinus membrane elevation, maxillary sinus, bone grafting.     

A comparison of the implant stability among various implant systems: clinical study

PURPOSE

To determine the change in stability of single-stage, three different design of implant systems in humans utilizing resonance frequency analysis for early healing period (24 weeks), without loading.

MATERIAL AND METHODS

Twenty-five patients were included into this study. A total of 45 implants, three different design of implant systems (group A,C,R) were placed in the posterior maxilla or mandible. The specific transducer for each implant system was used. ISQ (implant stability quotient) reading were obtained for each implant at the time of surgery, 3, 6, 8, 10, 12, 24 weeks postoperatively. Data were analyzed for different implant type, bone type, healing time, anatomical locations.

RESULTS

For each implant system, a two-factor mixed-model ANOVA demonstrated that a significant effect on ISQ values (group A = 0.0022, C = 0.017, R = 0.0018). For each implant system, in a two-factor mixed model ANOVA, and two-sample t-test, the main effect of jaw position (P > .005) on ISQ values were not significant.

CONCLUSIONS

All the implant groups A, C and R, the change patterns of ISQ over time differed by bone type. Implant stability increased greatly between week 0 and week six and showed slow increase between week six and six months (plateau effect).     

Sinus Elevation with an Alloplastic Material and Simultaneous Implant Placement: A 1-Stage Procedure in Severely Atrophic Maxillae

Aims and objective

The aim of the study is to evaluate clinically and radiographically the long term success of one-stage direct (lateral) sinus lift procedure using alloplastic bone graft material and bio-absorbable membrane in conjunction with two stage implant placement in atrophic partially edentulous posterior maxilla.

Materials and methods

One stage direct maxillary sinus lift in conjunction with two stage implant placement was carried out in 12 patients at 13 sites. All the patients were partially edentulous with posterior maxillary alveolar ridge height of >5 mm and were in the age group of 20–50 years. Bioactive glass putty, bio-absorbable collagen membrane and 3.75 × 11.5 mm implants were used. Loading of implants was done 6 months after placement of implants. Patients were evaluated clinically and radio-graphically 6, 18, 30 months after placement of implants to assess increase in residual ridge height, peri-implant condition (marginal bone loss, plaque and gingival index) and implant stability.

Results

Maxillary first molar was the most common site (69.23 %) for sinus lift and implant placement. Caries was the most common cause (76.92 %) for loss of tooth. Increase in residual ridge height ranged from (71.43 to 133.33 %) as measured by Denta-Scan. Implant survival rate was 100 %. Marginal bone loss ranged from 0.68 to 1.22 mm. Implant stability was measured by periotest (−2.7 to −3.6). Only one patient had perforation of sinus membrane, but it was sealed satisfactorily by bio-absorbable membrane.

Conclusion

One stage lateral sinus lift procedure with alloplastic bone graft material in combination with 2 stage implant placement has a predictable outcome in patients with severe resorption of posterior maxilla.     

Radiographic Evaluation of Crestal Bone Loss Around Dental Implants in Maxilla and Mandible: One Year Prospective Clinical Study

Purpose

The aim of the study was to analyze the amount of maxillary and mandibular crestal bone loss around Bredent Sky Blue type of implants of different dimensions one year after implantation.

Materials and Methods

36 implants of diameter 3.5 x 10 mm were inserted in the maxilla and 12 in the mandible. 52 implants of diameter 4.0 x 8 mm were inserted in the maxilla, and 61 in the mandible (two-stage implant surgery).

Results

No statistically significant differences were found between the right and left side of the maxilla and between the right and left side of the mandible at the implant sites regarding distal and mesial bone losses as shown by analysis of variance (ANOVA).

Conclusion

Statistically significant differences were found between anterior maxilla, posterior maxilla and anterior mandible and posterior mandible at implant sites regarding distal and mesial bone losses as shown by analysis of variance (ANOVA).Key words: Alveolar Bone Loss, Bone Resorption, Dental Implants, Maxilla, Mandible     

A comparative study on the initial stability of different implants placed above the bone level using resonance frequency analysis

PURPOSE

This study evaluated the initial stability of different implants placed above the bone level in different types of bone.

MATERIALS AND METHODS

As described by Lekholm and Zarb, cortical layers of bovine bone specimens were trimmed to a thickness of 2 mm, 1 mm or totally removed to reproduce bone types II, III, and IV respectively. Three Implant system (Brånemark System® Mk III TiUnite™, Straumann Standard Implant SLA®, and Astra Tech Microthread™-OsseoSpeed™) were tested. Control group implants were placed in level with the bone, while test group implants were placed 1, 2, 3, and 4 mm above the bone level. Initial stability was evaluated by resonance frequency analysis. Data was statistically analyzed by one-way analysis of variance in confidence level of 95%. The effective implant length and the Implant Stability Quotient (ISQ) were compared using simple linear regression analysis.

RESULTS

In the control group, there was a significant difference in the ISQ values of the 3 implants in bone types III and IV (P<.05). The ISQ values of each implant decreased with increased effective implant length in all types of bone. In type II bone, the decrease in ISQ value per 1-mm increase in effective implant length of the Brånemark and Astra implants was less than that of the Straumann implant. In bone types III and IV, this value in the Astra implant was less than that in the other 2 implants.

CONCLUSION

The initial stability was much affected by the implant design in bone types III, IV and the implant design such as the short pitch interval was beneficial to the initial stability of implants placed above the bone level.     

The effect of various thread designs on the initial stability of taper implants

STATEMENT OF PROBLEM

Primary stability at the time of implant placement is related to the level of primary bone contact. The level of bone contact with implant is affected by thread design, surgical procedure and bone quality, etc.

PURPOSE

The aim of this study was to compare the initial stability of the various taper implants according to the thread designs, half of which were engaged to inferior cortical wall of type IV bone (Group 1) and the rest of which were not engaged to inferior cortical wall (Group 2) by measuring the implant stability quotient (ISQ) and the removal torque value (RTV).

MATERIAL AND METHODS

In this study, 6 different implant fixtures with 10 mm length were installed. In order to simulate the sinus inferior wall of type IV bone, one side cortical bone of swine rib was removed. 6 different implants were installed in the same bone block following manufacturer''s recommended procedures. Total 10 bone blocks were made for each group. The height of Group 1 bone block was 10 mm for engagement and that of group 2 was 13 mm. The initial stability was measured with ISQ value using Osstell mentor® and with removal torque using MGT50 torque gauge.

RESULTS

In this study, we found the following results. 1. In Group 1 with fixtures engaged to the inferior cortical wall, there was no significant difference in RTV and ISQ value among the 6 types of implants. 2. In Group 2 with fixtures not engaged to the inferior cortical wall, there was significant difference in RTV and ISQ value among the 6 types of implants (P < .05). 3. There was significant difference in RTV and ISQ value according to whether fixtures were engaged to the inferior cortical wall or not (P < .05). 4. Under-drilling made RTV and ISQ value increase significantly in the NT implants which had lower RTV and ISQ value in Group 2 (P < .05).

CONCLUSIONS

Without being engaged to the inferior cortical wall fixtures had initial stability affected by implant types. Also in poor quality bone, under-drilling improved initial stability.     

The relationship between initial implant stability quotient values and bone-to-implant contact ratio in the rabbit tibia

PURPOSE

Implant stability quotient (ISQ) values have been supposed to predict implant stability. However, the relationship between ISQ values and bone-to-implant contact ratio (BIC%) which is one of the predictors of implant stability is still unclear. The aim of the present study was to evaluate initial ISQ values in relation to BIC% using rabbit model.

MATERIALS AND METHODS

Four New Zealand white rabbits received a total of 16 implants in their tibia. Immediately after implant placement ISQ values were assessed. The measurements were repeated at the time of sacrifice of the rabbits after 4 weeks. Peri-implant bone regeneration was assessed histomorphometrically by measuring BIC% and bone volume to total volume values (bone volume %). The relationships between ISQ values and the histomorphometric output were assessed, and then, the osseointegration prediction model via the initial ISQ values was processed.

RESULTS

Initial ISQ values showed significant correlation with the BIC%. The bone volume % did not show any significant association with the ISQ values.

CONCLUSION

In the limitation of this study, resonance frequency analysis is a useful clinical method to predict the BIC% values and examine the implant stability.     

Effect of implant macro-design on primary stability: A prospective clinical study

Background

Implant restorations have become a high predictable treatment option. Several caracteristics such as surgical technique and implant design can influence the treatment outcomes. The aim of the present study was to evaluate the influence of implant macro-design on primary stability measured with resonance frequency analysis (RFA) and insertion torque (IT).

Material and Methods

A total of 47 implants divided in two groups: Test group (TI): 22 Tapered MIS® Seven implants; Control group (CI): 25 cylindrical Astra® Osseospeed implants. All implants were inserted following the manufacturers’ standard protocols. Implant primary stability was measured at the moment of implant placement by registering insertion torque values (ITv) and ISQ values by means of Osstell™ Mentor (ISQv) (Integration Diagnostic Ltd., Goteborg, Sweden).

Results

In the mandible, mean ISQv for tapered implants (TI) was 71.67±5.16 and for cylindrical implants (CI) 57.15±4.83 (p=0.01). Mean insertion torque was 46.67±6.85 Ncm for TI and 35.77±6.72 Ncm for CI (p=0.01). In the maxilla, mean ISQ was 67.2±4.42 for tapered implants and 49.17±15.30 for cylindrical implants (p=0.01). Mean insertion torque for TI was 41.5±6.26 Ncm and for CI 39.17±6.34 Ncm (p>0.05). For tapered implants, no correlation could be found between implant diameter and primary stability. But for cylindrical implants there was a statistically significant correlation between implant diameter and primary stability: ITv (p=0.03); ISQv (p=0.04).

Conclusions

Within the limits of the present study, tapered shaped implants achieve higher primary stability measured through ISQ and insertion torque values. Moreover, for cylindrical implants positive correlation has been established between implant diameter and primary stability. Key words:Primary stability, tapered, cylindrical, conical, implant macro-design.     

Comparion of stability in titanium implants with different surface topographies in dogs

STATEMENT OF PROBLEM

A few of studies which compared and continuously measured the stability of various surface treated implants in the same individual had been performed.

PURPOSE

We aim to find the clinical significance of surface treatments by observing the differences in the stabilization stages of implant stability.

MATERIAL AND METHODS

Eight different surface topographies of dental implants were especially designed for the present study. Machined surface implants were used as a control group. 4 nano-treated surface implants (20 nm TiO₂ coating surface, heat-treated 80 nm TiO₂ coating surface, CaP coating surface, heat treated CaP coating surface) and 3 micro-treated surface implants [resorbable blast media (RBM) surface, sandblast and acid-etched (SAE) surface, anodized RBM surface] were used as experiment groups. All 24 implants were placed in 3 adult dogs. Periotest® & ISQ values measured for 8 weeks and all animals were sacrificed at 8 weeks after surgery. Then the histological analyses were done.

RESULTS

In PTV, all implants were stabilized except 1 failed implants. In ISQ values, The lowest stability was observed at different times for each individual. The ISQ values were showed increased tendency after 5 weeks in every groups. After 4 to 5 weeks, the values were stabilized. There was no statistical correlation between the ISQ values and PTV. In the histological findings, the bone formation was observed to be adequate in general and no differences among the 8 surface treated implants.

CONCLUSIONS

In this study, the difference in the stability of the implants was determined not by the differences in the surface treatment but by the individual specificity.     

Use of buccal fat pad to repair post-extraction peri-implant bone defects in the posterior maxilla. A preliminary prospective study

Background

Extensive literature exists about the use of the BFP in the treatment of oral defects but, to our knowledge, no article refers to the use of the BFP as a substitute of the membrane barriers for treatment of peri-implant bone defects. The aim was to evaluate the use of the buccal fat pad as a coating material for bone grafting in the peri-implant bone defect regeneration of immediate implants placed in the posterior maxilla.

Material and Methods

A preliminary prospective study of patients involving immediate implants in which the buccal fat pad was used as a coating material to peri-implant bone defects was carried out. The outcome measures assessed were: postoperative pain and swelling, complications related to buccal fat pad surgery, implant survival and success rates and peri-implant marginal bone loss at 12 months of prosthetic loading.

Results

Twenty-seven patients (17 women and 10 men) with a mean age of 55.3 ± 8.9 years, and a total of 43 implants were included. Two-thirds of the patients reported either no pain or only mild intensity pain and moderate inflammation, two days after surgery. Post-operative period was well tolerated by the patients and no serious complications occurred. None wound dehiscence occurred. Implant survival and success rates were 97.6% and the average marginal bone loss 1 year after loading was 0.58 ± 0.27 mm.

Conclusions

Within the limits of this preliminary study, the use of the buccal fat pad as a coating material for bone grafting in peri-implant bone defects placed in the upper posterior maxilla was a well-tolerated technique by patients; high implant success rate was achieved with a minimal peri-implant marginal bone loss at 12 months of prosthetic loading. Key words:Buccal fat pad, immediate implant, peri-implant bone defect.     

Maxillary Sinus Augmentation with Autologous and Heterologous Bone Graft: A Clinical and Radiographic Report of Immediate and Delayed Implant Placement

Purpose

The aim of this study was to evaluate cumulative survival rate of implants placed on augmented maxillary sinus using a mixture of autologous bone harvested from the maxillary tuberosity and bovine-derived HA and to assess the height of the grafted material through radiographic evaluation.

Methods

Thirty-five patients were treated with maxillary sinus augmentation and 93 implant fixtures were installed. The height of the augmented sinus and the gain of bone volume were measured by Cone Beam CT Scan and intraoral radiographs immediately after augmentation and up to 48 months subsequently. Changes in the height of the sinus graft material were calculated radiographically.

Results

The cumulative survival rate was 98.92 % in all 93 implants. Additionally, normal healing process without any complication was observed in all patients. The original sinus height was a mean of 4.52 mm (range 2.0–6.4 mm) and the augmented sinus height was a mean of 14.1 mm (range 12.0–16.5 mm) after the surgery. The bone volume gain was a mean 9.613 mm (range 7–13 mm).

Conclusions

Within the limitations of this study, it would appear from the clinical and radiographic results that the sinus lift procedure with autologous bone graft harvested from the maxillary tuberosity combined with deproteinized bovine bone allows for a predictable outcome regarding the amount of bone formation in sinus floor augmentation and the immediate placement of implants, when possible, is recommended.     

Survival Rate for Implants Placed in the Posterior Maxilla With and Without Sinus Augmentation: A Comparative Cohort Study

Background: The reduced bone height and proximity of the maxillary sinus are the most common limitations for placement of dental implants in the posterior maxilla. Reconstruction of the atrophic posterior maxilla can be performed with a sinus augmentation procedure. The aim of this cohort study is to compare the survival rate of implants placed in augmented sinus to implants placed in native bone in the posterior maxilla. Methods: This study was designed as a prospective cohort study and included consecutively treated patients. Patients who required the sinus augmentation (test group) were treated according to the two‐stage technique. Patients were scheduled for follow‐up evaluation at 3, 6, and 12 months after implant placement and then every 6 months for ≤6 years. Results: One hundred and five patients with 393 implants were enrolled in the study. Two hundred and one implants were placed after preliminary sinus floor grafting in 41 patients. The control group contained 64 patients with 192 implants that were placed in pristine bone of the posterior maxilla. The cumulative implant survival rates were 86.1% and 96.4%, respectively. The difference between the two groups was highly significant (P <0.005). Conclusions: These findings show that implants placed in augmented sinuses had a lower survival rate compared to implants placed in pristine bone. All the implant failures in the augmented sinuses occurred before the prosthetic rehabilitation. Moreover, it should be considered that most of the failures were observed in few patients, thus suggesting cluster behavior.     

Experimental study on penetration of dental implants into the maxillary sinus in different depths

The exposing of dental implant into the maxillary sinus combined with membrane perforation might increase risks of implant failure and sinus complications.

Objective

The purpose of this study was to investigate the effects of the dental implant penetration into the maxillary sinus cavity in different depths on osseointegration and sinus health in a dog model.

Material and Methods

Sixteen titanium implants were placed in the bilateral maxillary molar areas of eight adult mongrel dogs, which were randomly divided into four groups according to the different penetrating extents of implants into the sinus cavities (group A: 0 mm; group B: 1 mm; group C: 2 mm; group D: 3 mm). The block biopsies were harvested five months after surgery and evaluated by radiographic observation and histological analysis.

Results

No signs of inflammatory reactions were observed in any maxillary sinus of the eight dogs. The tips of the implants with penetrating depth of 1 mm and 2 mm were found to be fully covered with newly formed membrane and partially with new bone. The tips of the implants with penetrating depth over 3 mm were exposed in the sinus cavity and showed no membrane or bone coverage. No significant differences were found among groups regarding implant stability, bone-to-implant contact (BIC) and bone area in the implant threads (BA).

Conclusions

Despite the protrusion extents, penetration of dental implant into the maxillary sinus with membrane perforation does not compromise the sinus health and the implant osseointegration in canine.     

Biomechanical evaluation of dental implants with different surfaces: Removal torque and resonance frequency analysis in rabbits

STATEMENT OF PROBLEM

Macroscopic and especially microscopic properties of implant surfaces play a major role in the osseous healing of dental implants. Dental implants with modified surfaces have shown stronger osseointegration than implants which are only turned (machined). Advanced surface modification techniques such as anodic oxidation and Ca-P application have been developed to achieve faster and stronger bonding between the host bone and the implant.

PURPOSE

The purpose of this study was to investigate the effect of surface treatment of titanium dental implant on implant stability after insertion using the rabbit tibia model.

MATERIAL AND METHODS

Three test groups were prepared: sandblasted, large-grit and acid-etched (SLA) implants, anodic oxidized implants, and anodized implants with Ca-P immersion. The turned implants served as control. Twenty rabbits received 80 implants in the tibia. Resonance frequencies were measured at the time of implant insertion, 2 weeks and 4 weeks of healing. Removal torque values (RTV) were measured 2 and 4 weeks after insertion.

RESULTS

The implant stability quotient (ISQ) values of implants for resonance frequency analysis (RFA) increased significantly (P < .05) during 2 weeks of healing period although there were no significant differences among the test and control groups (P > .05). The test and control implants also showed significantly higher ISQ values during 4 weeks of healing period (P < .05). No significant differences, however, were found among all the groups. All the groups showed no significant differences in ISQ values between 2 and 4 weeks after implant insertion (P > .05). The SLA, anodized and Ca-P immersed implants showed higher RTVs at 2 and 4 weeks of healing than the machined one (P < .05). However, there was no significant difference among the experimental groups.

CONCLUSION

The surface-modified implants appear to provide superior implant stability to the turned one. Under the limitation of this study, however, we suggest that neither anodic oxidation nor Ca-P immersion techniques have any advantage over the conventional SLA technique with respect to implant stability.     

��ͬ��ʽֲ������������ֲ��Ĺ���Ƶ�ʷ����Ƚ�

??Objective    Use resonance frequency analysis??RFA??to quantitatively compare the stability of implants placed in the posterior maxillary sites with conventional implantation and by using 3 sinus augmentation techniques??osteotome sinus floor elevation and 1- and 2-step lateral window techniques??. Methods    A total of 103 patients?? with single implant or multiple Straumann implants ??139 implants in total??in the maxillary posterior area??were chosen from the implant center of Dalian Stomatological Hospital from 2013 to 2014. They were divided into four groups according to the residual ridge height??and the implants were implanted with the different technologies??conventional implantation??group A????osteotome sinus floor elevation??group B???? 1- and 2-step lateral window techniques??group C and D??. Implant stability quotient??ISQ??was recorded from RFA at the time of implant placement and 6 months later. Results    All implants had obtained osseointegration. The differences in ISQ at placement versus 6 months later were statistically significant??P < 0.05??in each group??average increase of ISQ being 4.96 ± 2.41??5.39 ± 2.09??4.47 ± 1.48 and 5.16 ± 1.99??respectively. The statistically significant difference in ISQ among four groups was found in the 4 groups neither at placement nor 6 months later??P > 0.05??. Conclusion    In atrophic posterior maxilla??the reasonable treatment options can be selected according to native vertical bone height. There was no statistical difference on ISQ among 3 sinus augmentation techniques??osteotome sinus floor elevation and 1- and 2-step lateral window techniques. All implants obtain osseointegration. The clinical outcomes among different technique of placement can be quantitatively compared by ISQ??which is measured by RFA.     

Effect of bone quality and implant surgical technique on implant stability quotient (ISQ) value

PURPOSE

This study investigated the influence of bone quality and surgical technique on the implant stability quotient (ISQ) value. In addition, the influence of interfacial bone quality, directly surrounding the implant fixture, on the resonance frequency of the structure was also evaluated by the finite element analysis.

MATERIALS AND METHODS

Two different types of bone (type 1 and type 2) were extracted and trimmed from pig rib bone. In each type of bone, the same implants were installed in three different ways: (1) Compaction, (2) Self-tapping, and (3) Tapping. The ISQ value was measured and analyzed to evaluate the influence of bone quality and surgical technique on the implant primary stability. For finite element analysis, a three dimensional implant fixture-bone structure was designed and the fundamental resonance frequency of the structure was measured with three different density of interfacial bone surrounding the implant fixture.

RESULTS

In each group, the ISQ values were higher in type 1 bone than those in type 2 bone. Among three different insertion methods, the Tapping group showed the lowest ISQ value in both type 1 and type 2 bones. In both bone types, the Compaction groups showed slightly higher mean ISQ values than the Self-tapping groups, but the differences were not statistically significant. Increased interfacial bone density raised the resonance frequency value in the finite element analysis.

CONCLUSION

Both bone quality and surgical technique have influence on the implant primary stability, and resonance frequency has a positive relation with the density of implant fixture-surrounding bone.     

Influence of cortical bone anchorage on the primary stability of dental implants

Purpose

This retrospective chart review study assessed patient records to determine implant insertion torque (IT) and implant stability quotient (ISQ) values during implant placement to evaluate the correlation with cortical bone anchorage (mono- or bicortical).

Methods

Primary stability data (IT during implant placement surgery and ISQ values immediately after implant placement) and cone beam computed tomography of 33 patients (165 implants) were assessed. Patients were divided into the following groups: G1, implants with apical cortical bone contact; G2, implants with bicortical bone contact (apical and cervical regions); and G3, implants with cervical cortical bone contact.

Results

Sixty-eight implants were excluded due to cortical bone contact on regions other than implant apical or cervical. Ninety-seven implants were therefore assessed for this study. No implant failure was found after a mean 70.42-month follow-up time. Implants with bicortical anchorage (G2) showed higher IT (64.1 Ncm) during implant placement and higher ISQ values (76) (p?<?0.05). Monocortical implants (G1, apical, and G3, cervical) showed similar IT (G1 52.3 and G3 54.3) and ISQ values (G1 71.9 and G3 73) (p?>?0.05). No correlation (Pearson correlation coefficient) was found between the two stability measurement devices for the different cortical bone anchorages that were analyzed (G1 0.190, G2 0.039, and G3 ??0.027) (p?>?0.05).

Conclusions

Insertion torque values and implant stability quotients were influenced by cortical bone contact. No significant correlation was found between IT and ISQ values—higher insertion torque values do not necessarily lead to higher implant stability quotients.

     

A comparative study on the accuracy of the devices for measuring the implant stability

STATEMENT OF PROBLEM

How the ISQ values measured by Osstell™ and Osstell™ Mentor are related, and whether the ISQ values acquired from the two machines changes in accordance with changes in implant stability are not yet fully understood.

PURPOSE

The aim of this study was to find out correlation between the ISQ values acquired from Osstell™ and Osstell™ Mentor, and to evaluate the clinical effectiveness and accuracy of two devices.

MATERIAL AND METHODS

Sixty two implants were inserted into 47 patients, and their ISQ values were measured using Osstell™ and Osstell™ Mentor. In the first stage surgery, the ISQ values of forty four implants inserted into thirty five patients were measured. In the second stage surgery, the values of fifty implants inserted into thirty seven patients were measured. The values were analyzed to determine the difference between the mean ISQ values of Osstell™ and Osstell™ Mentor. In addition, the correlation between implants used in the first and second stage of surgery with regard to their types and areas of insertion were analyzed. The difference between the ISQ values of 32 implants in each patient during the first and second stage was analyzed. The statistical assessment was carried out using SPSS V. 12.0 for Win. (SPSS Inc., Chicago, USA). The Pearson correlation coefficient was used to examine the correlation between Osstell™ and Osstell™ Mentor in the first and second stages of surgery, whereas the difference between their ISQ values was evaluated using a paired t-test.

RESULTS

In the first stage, the mean ISQ value for Osstell™ and Osstell™ Mentor was 70.84 and 75.09, respectively, showing a significant difference (P < .01). In the second stage, the mean ISQ value of Osstell™ and Osstell™ Mentor was 71.76 and 75.94, respectively, also showing a significant difference (P < .01). The difference between the ISQ values in patients in the first and the second stages was significant with both instruments.

CONCLUSION

The significant difference in the values obtained using the Osstell™ and Osstell™ Mentor between the first and second stages of implant surgery indicates that these values can be a convenient and precise way for evaluating the implant stability in clinical practice.     

Resonance frequency analysis of stability on ITI implants with osteotome sinus floor elevation technique without grafting: a 5-month prospective study

Objective: The aim of the present study was to (1) monitor the stability changes of ITI implants placed in atrophic posterior maxillary ridges with osteotome sinus floor elevation (OSFE) without grafting during the first 5 months of healing utilizing resonance frequency analysis (RFA) and (2) determine the factors that affect the implant stability quotient (ISQ) at placement and healings. Material and methods: Forty‐two ITI implants were placed in the posterior maxilla in 32 patients with OSFE without bone grafting. The residual vertical bone height ranged from 4 to 8 mm (average 6.36 mm). Bone type was classified into one to four groups according to the Lekholm and Zarb index. ISQ was tested on the day of surgery and consecutively at 2, 4, 6, 8, 12, 16, and 20 weeks by RFA. Results: The 40 osseointegrated implants represented a survival rate of 95.2%. All the 40 implants achieved good primary stability and reached a comparably high stability at 16 weeks postoperation with a dip between 2 and 6 weeks in the stability curve. There was no significant difference of ISQ between type3 and type4 bone at implant placement and follow‐up. The mean ISQ and its changing pattern did not demonstrate a statistically significant difference according to the pretreatment vertical bone height and implant length. Conclusions: The findings of this study indicated that uneventful osseointegration may be predictable applying OSFE alone with no grafting in atrophic posterior maxilla. Residual bone height (RBH), implant length, and bone type did not seem to affect the implant stability in this clinical situation.