The Influence of Implant Shape on Primary Stability of Implants With a Thread Cutting and Forming Design: An Ex Vivo Study

"Compression Necrosis" - A Cause of Concern for Early Implant Failure? Case Report and Review of Literature

Purpose

Compression necrosis refers to bone tissue damage that can occur when excessive pressure or force is applied to surrounding bone during implant placement. This pressure can compromise blood supply to the bone, leading to necrosis. Compression necrosis is a concern, because it can affect the stability and long-term success of dental implant.

Patients and Methods

This case report highlights a case of early bone loss and implant failure possibly due to compression necrosis. Clinical data, photographs, radiographs, blood examination report and histology were presented to document the early failure of an implant placed in the mandibular left posterior region of a 33-year-old female patient.

Results

Radiograph taken six weeks after implant placement showed severe angular defect. Therefore, the implant was surgically removed. Histological examination of the area showed bony trabeculae with an absence of osteoblastic riming, suggestive of necrotic bone.

Conclusion

Using excessive torque values when placing implants in dense bones can increase the risk of implant failure due to bone over compression. Dental professionals must follow the manufacturer's instructions and employ quality surgical techniques during implant placement into dense cortical bone to minimise risks.

Relationship between dental implant macro-design and osseointegration: a systematic review

PURPOSE

This systematic review aimed to determine whether differences in the macro-geometry of titanium implants promote changes in osseointegration.

MATERIAL AND METHOD

SCOPUS, PubMed/Medline, Web of Science, and EMBASE databases were searched in June 2021. In addition, it was performed a manual search of the reference lists of the included articles. Eligibility criteria were in vivo studies that addressed the effect of titanium implant macro-geometry on osseointegration, studies that evaluated periodontally healthy models, and papers indexed in Journal Citation Reports.

RESULTS

The database search resulted in 1037 articles. Of the 19 articles selected for full reading, 16 remained in this systematic review. These had a high heterogeneity making it hard to perform statistical analysis of the data, so a descriptive analysis was performed.

CONCLUSIONS

Based on the studies included in this systematic review, implant macro-geometry provides influences on osseointegration. In this sense, the various isolated characteristics (thread type, thread pitch, thread depth, face angle) should be studied so that the implant geometry can balance the compressive stress and tensile stress and produce a minimum shear force.

Comparison of reliability of three resonance frequency analysis devices: An in vitro study

The purpose of the present study was to investigate the intra-observer and inter-observer reliability of three resonance frequency analysis (RFA) devices and to compare the implant stability quotient (ISQ) values according to implant macro design and diameter in two different bone densities. A total of 64 implants (Neoss Proactive) of varying diameters (3.5 and 4.0 mm) and implant macro design (tapered and straight) were placed in two artificial bone blocks (the density of type 2 and 3). The implant primary stability was measured using Osstell IDx, Osstell Beacon and Penguin RFA. The ISQ value of each implant was measured by two observers and recorded five times in two directions. The intra-observer and inter-observer reliability of RFA devices were evaluated. In addition to that, mean ISQ values were calculated for each RFA device to evaluate the effect of implant diameter, implant macro design, and bone density on ISQ values. ISQ values were significantly higher for implants placed within the type 2 bone than for the type 3 bone. The 4.0 mm diameter implants presented higher ISQ values than 3.5 mm diameter implants. The intra-class correlation coefficient (ICC) values for intra-observer reliability were above 0.85 for each observer and the ICC values for inter-observer reliability were 0.94, 0.93, 0.98 for Osstell IDx, Osstell Beacon and Penguin RFA, respectively. Although there was excellent inter-observer reliability with three RFA devices, the intra-observer reliability of Osstell Beacon and Penguin RFA were slightly better than Osstell IDx. Bone density and implant diameter were parameters affecting the primary stability of implants.

Primary stability of narrow-diameter dental implants with a multiple condensing thread design placed in bone with and without osteotomes: An in vitro study

BACKGROUND

The authors hypothesized that there is no difference in the primary stability (PS) of multiple condensing thread design (MCTD) implants placed in simulated type-IV bone with and without using osteotomes.

PURPOSE

This in vitro study assessed the PS of narrow-diameter dental implants with MCTD placed in simulated soft (type-IV) bone with and without using osteotomes.

MATERIALS AND METHODS

Sixty MCT-designed implants (diameter: 3.0 mm; length: 11.5 mm) were placed using 800 rpm drilling speed in cellular rigid polyurethane foam bone-blocks that simulated type-IV bone. Prior to placement, the implants were divided into three groups (20 implants per group) depending upon the protocol used for osteotomy preparation-Group-1: Conventional drilling (CD); Group-2: CD followed by osseous condensation using a chisel-shaped tapered osteotome with maximum diameter of 3 mm; and Group-3: CD followed by osseous condensation using a cylindrical osteotome with maximum diameter of 3 mm. Abutments were connected to all implants and PS was recorded using resonance frequency analysis (RFA) and the periotest (PTV). Group comparisons were performed using analysis and Bonferroni post-hoc adjustment tests. Level of significance was set at P < .05.

RESULTS

There was no statistically significant difference in the RFA values for the MCT-designed implants placed in groups 1, 2, and 3 (59.85 ± 0.72, 59.67 ± 0.76 and 59.42 ± 0.92, respectively). There was no statistically significant difference in the PTV values for MCT-designed implants in groups 1, 2, and 3 (1.655 ± 0.82, 1.405 ± 0.57, and 1.078 ± 0.63, respectively).

CONCLUSION

The MCTD implants with narrow diameters have a high PS in artificial soft bone in vitro. Due to the condensation effect of the thread design, there is no need for additional condensation of the peri-osteotomy bone in order to improve implant stability.