Influence of Resonance Frequency Analysis (RFA) Measurements for Successful Osseointegration of Dental Implants During the Healing Period and Its Impact on Implant Assessed by Osstell Mentor Device

Does the index in Morse taper connection affect the abutment stability? An in vitro experimental study

The present study compared three different implant and abutment sets of type Morse taper (MT) connection, with- and without-index, were analyzed regarding their mechanical behavior without and with cyclic load application simulating the masticatory function. Ninety implant and abutment (IA) sets were used in the present study, divided into three groups (n = 30 samples per group): Group A, Ideale solid straight abutment (one piece) without index; Group B, Ideale abutment with an angle of 30-degree (two pieces) without index; Group C, Ideale abutment with an angle of 30-degree (two pieces) with index. The abutment stability quotient (ASQ) values, detorque value and rotation angle were measured before and after the cycling load. Twenty IA sets of each group were submitted to mechanical load at 360,000 cycles. The ASQ without load were 64.7 ± 2.49 for the group A, 60.2 ± 2.64 for the group B, 54.4 ± 3.27 for the group C; With load were 66.1 ± 5.20 for the group A, 58.5 ± 6.14 for the group B, 58.9 ± 2.99 for the group C. Detorque values were lower in groups B and C compared to group A (p < 0.05). In conclusion, the presence of the index did not influence the stability values. However, solid straight abutments (group A) showed higher values of stability compared to groups of angled abutments (groups B and C).

Influencing factors and evaluation methods for early stability of immediate implant

At present, implant restoration has become a hot research topic in the field of prosthodontics. The in-depth studies of new materials and new technologies enable immediate implantation, immediate and early loading to be realized, which meets the needs of patients for shortening the course of implant restoration and obtaining better aesthetic effects. However, compared with the traditional delayed implantation technology, it is equally challenging for clinicians how to achieve and even improve the initial and long-term stability of implants in order to raise the success rate of implant restoration. The initial stability of the implant is influenced by a combination of factors, including the implant, the patient's condition, and the surgical procedure. Recently, there have been a lot of studies on the influencing factors and common research methods for immediate implant stability and bone healing. Summarizing and analyzing them can provide reference for preoperative evaluation, surgical plan and loading timing of immediate implant restoration in the later stage.

Is Acoustic modal analysis a reliable substitution for Osstell® device in dental implant stability assessment? An experimental and finite element analysis study

BACKGROUND

Different methods have been proposed to investigate the fixation stability of dental implants, each of which has its limitations. Among these methods, resonance frequency analysis (RFA) has been widely utilized to measure dental implant stability. This study aimed to assess dental implants with two non-destructive RFA and acoustic modal analysis (AMA) validated with a finite element simulation of the fundamental natural frequency (NF) of the bone analog-implant structure.

MATERIAL AND METHODS

A total number of 18 implants were inserted into two Polyurethane (PU) bone blocks with different densities (0.16 g/cc and 0.32 g/cc). AMA was used to measure NF; First, the sound originating from the axial tapping of the implant was recorded with a simple microphone. Secondly, a fast Fourier transformation algorithm was conducted to determine the NF of the implant-bone analog structure. In parallel, the ISQ (Implant Stability Quotient) value was measured using the Osstell® device. Finally, using finite element analysis (FEA), the implant-bone analog structure was modeled for validation.

RESULTS

Doubling the bone analog density resulted in an average increase of 82% and 47% in the NF and ISQ using AMA and Osstell®, respectively (P-value<0.05). Furthermore, a strong linear relationship (R2= 0.93) was observed between the measured NF and ISQ values in the linear regression analysis. The NF of the dental implant predicted by FEA was overestimated by about 15.2% and 15.0% than those in the low- and high-density PUs, respectively. Moreover, the FEA predicted an increase of 83% in NF by increasing the bone analog density from 0.16 to 0.32 g/cc.

CONCLUSIONS

Having required the minimum process combined with easily available equipment makes it an ideal method for fixation strength studies. The good correspondence between the ISQ values and NFs, in addition to the good accuracy and reliability of the later method, confirms its application for fixation stability assessment.

Determining primary stability for adhesively stabilized dental implants

OBJECTIVES

To examine factors influencing the primary stability of dental implants when stabilized in over-sized osteotomies using a calcium phosphate-based adhesive cement was the objective.

METHODS

Using implant removal torque measurements as a surrogate for primary stability, we examined the influence of implant design features (diameter, surface area, and thread design), along with cement gap size and curing time, on the resulting primary implant stability.

RESULTS

Removal torque values scaled with implant surface area and increasing implant diameters. Cement gap size did not alter the median removal torque values; however, larger gaps were associated with an increased spread of the measured values. Among the removal torque values measured, all were found to be above 32 Ncm which is an insertion torque threshold value commonly recommended for immediate loading protocols.

CONCLUSION

The adhesive cement show potential for offering primary implant stability for different dental implant designs. In this study, the primary parameters influencing the measured removal torque values were the implant surface area and diameter. As the liquid cement prevents the use of insertion torque, considering the relationship between insertion and removal torque, removal torque can be considered a reliable surrogate for primary implant stability for bench and pre-clinical settings.

CLINICAL RELEVANCE

At present, the primary stability of dental implants is linked to the quality of the host bone, the drill protocol, and the specific implant design. The adhesive cement might find applications in future clinical settings for enhancing primary stability of implants under circumstances where this cannot be achieved conventionally.

Awareness on resonance frequency analysis in dental implantology among dental practitioners and dental students

In a partial or entirely independent jaw, oral implantology is a technique in dentistry used to enhance the function of mastication, esthetics, and phonation. An important diagnostic aspect for the effectiveness of implant therapy is the stability of the implants. This study aims to measure dental professionals' and dental students' knowledge of resonance frequency analysis (RFA) in dental implantology. This study aims to measure dental professionals' and dental students' knowledge of RFA in dental implantology. One hundred ninety-nine dentists and dental students participated in an online survey study that was delivered through Google Forms. For statistical analysis, tabulated data from the Excel sheets were transferred into the SPSS program. The Chi-square test is also used to examine clinical relevance. According to the study's findings, 60% of the respondents were male and 46% of those who responded were dental professionals. The respondents were primarily between the ages of 18 and 22 (36%). The majority of dental undergraduates and graduates were found to be knowledgeable about the various techniques used to gauge implant stability (P = 0.04 < 0.05). Within the limitations of this study, it was found that most of the dental students and dental practitioners participating in this study were aware of implant stability. The majority of the respondents were aware that RFA was used to measure primary and secondary stability and osseointegration.

Effect of supplemental acid-etching on the early stages of osseointegration: A preclinical model

PURPOSE

To evaluate the effect of two surface modifications on early osseointegration parameters of conical implants in a translational pre-clinical model.

MATERIALS AND METHODS

Conical implants with progressive trapezoidal threads and healing chambers were evaluated consisting of two different surface conditions: 1) Implacil surface (IMP Sur), and 2) Implacil surface + Supplemental Acid-etching (IMP Sur + AE). Surface characterization comprised of the evaluation of roughness parameters (S_a, S_q and S_dr), surface energy and contact angle. Subsequently, implants were installed in the ilium crest of nine female sheep (weighing ~65 kg). Torque out, histological and histomorphometric analyses were conducted after 3 and 6 weeks in-vivo. The percentage of bone to implant contact (%BIC) and bone area fraction occupancy within implant threads (%BAFO) were quantified, and the results were analyzed using a general linear mixed model analysis as function of surface treatment and time in-vivo.

RESULTS

Supplemental acid etching significantly increased S_a and S_q roughness parameters without compromising the surface energy or contact angle, and no significant differences with respect to S_dr. Torque-out testing yielded significantly higher values for IMP Sur + AE in comparison to the IMP Sur at 3- (62.78 ± 15 and 33.49 ± 15 N.cm, respectively) and 6-weeks (60.74 ± 15 and 39.80 ± 15 N.cm, respectively). Histological analyses depicted similar osseointegration features for both surfaces, where an intramembranous-type healing pattern was observed. At histomorphometric analyses, IMP Sur + AE implants yielded higher values of BIC in comparison to IMP Sur at 3- (40.48 ± 38 and 27.98 ± 38%, respectively) and 6-weeks (45.86 ± 38 and 34.46 ± 38%, respectively). Both groups exhibited a significant increase in %BAFO from 3 (~35%) to 6 weeks (~44%), with no significant differences between surface treatments.

CONCLUSION

Supplemental acid-etching and its interplay with implant thread design, positively influenced the BIC and torque-out resistance at early stages of osseointegration.