Stability of dental implants with sandblasted and acid-etched (SLA) and modified (SLActive) surfaces during the osseointegration period

Impact of Implant Surface and Smoking on Peri-Implant Human Bone: What we Learned from The Last 20 Years?

The present review summarizes the findings from human histological studies conducted over the past 20 years at the University of Guarulhos, Brazil, examining the impact of various implant surface topographies and smoking on peri-implant bone response. Seven different implant surfaces were evaluated in 90 partially or completely edentulous individuals using a total of 123 micro-implants. Histometric parameters, including bone-implant contact (BIC%), bone area within the threads (BA%), and bone density (BD), were assessed after an 8-week healing period. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses were also performed. Results showed that treated surfaces, regardless of the treatment type, consistently demonstrated better histometric outcomes compared to machined surfaces. Anodized surfaces and those subjected to airborne particle abrasion, followed by acid etching, exhibited higher BIC% values than machined surfaces in smoker patients. Smoking reduced BIC% around anodized implants. The presence of inflammatory cells was observed adjacent to the peri-implant soft tissue on some treated surfaces. In conclusion, implant surface topography significantly influences early bone response under unloaded conditions, with treated surfaces promoting better human bone tissue response than machined surfaces. However, smoking negatively impacts peri-implant bone healing, emphasizing the importance of smoking cessation for optimal osseointegration.

Innate immune regulation in dental implant osseointegration

PURPOSE

Dental implant osseointegration comprises two types of bone formation-contact and distance osteogenesis-which result in bone formation originating from the implant surface or bone edges, respectively. The physicochemical properties of the implant surface regulate initial contact osteogenesis by directly tuning the osteoprogenitor cells in the peri-implant environment. However, whether these implant surface properties can regulate osteoprogenitor cells distant from the implant remains unclear. Innate immune cells, including neutrophils and macrophages, govern bone metabolism, suggesting their involvement in osseointegration and distance osteogenesis. This narrative review discusses the role of innate immunity in osseointegration and the effects of implant surface properties on distant osteogenesis, focusing on innate immune regulation.

STUDY SELECTION

The role of innate immunity in bone formation and the effects of implant surface properties on innate immune function were reviewed based on clinical, animal, and in vitro studies.

RESULTS

Neutrophils and macrophages are responsible for bone formation during osseointegration, via inflammatory mediators. The microroughness and hydrophilic status of titanium implants have the potential to alleviate this inflammatory response of neutrophils, and induce an anti-inflammatory response in macrophages, to tune both contact and distance osteogenesis through the activation of osteoblasts. Thus, the surface micro-roughness and hydrophilicity of implants can regulate the function of distant osteoprogenitor cells through innate immune cells.

CONCLUSIONS

Surface modification of implants aimed at regulating innate immunity may be useful in promoting further osteogenesis and overcoming the limitations encountered in severe situations, such as early loading protocol application.

Analysis of osseointegration of implants with macrogeometries with healing chambers: a randomized clinical trial

BACKGROUND

To verify the influence of macrogeometry with healing chambers on the osseointegration of dental implants by analyzing implant stability quotient (ISQ) and evaluate the correlation between insertion torque and ISQ insertion with different macrogeometries.

METHODS

In total, 26 implants were installed in the posterior mandible of eight patients with sufficient bone height for the installation of implants measuring 3.5 mm in diameter and 9.0 mm in length. The implants were categorized according to two types of macrogeometry: a test group (GT) with 13 conical implants with healing chambers and a control group (GC) with 13 conical implants with conventional threads. To insert the implants, a bone drilling protocol was used up to a diameter of 3 mm with the last helical bur. The insertion torque of the implants was evaluated, followed by the measurement of ISQ at 0 (T-0), 7 (T-7), 14 (T-14), 21 (T-21), 28 (T-28), and 42 (T-42) days.

RESULTS

The mean insertion torque was 43 Ncm in both groups, without a significant difference. Moreover, no significant difference in the ISQ values was found between the groups at different time points (p > 0.05), except at T-7 (GT = 69.87±1.89 and GC = 66.48±4.49; p = 0.01). Although there was no significant difference, ISQ median values were higher in the GT group than GC group at 28 days (GT = 67.98 and GC = 63.46; p = 0.05) and 42 days (GT = 66.12 and GC = 60.33; p = 0.09). No correlation was found between the insertion torque and ISQ insertion (p > 0.05).

CONCLUSION

Furthermore, implants with a 3.5 mm diameter macrogeometry, with or without healing chambers, inserted with a drilling protocol up to 3 mm in diameter of the last helical bur, led to a similar secondary stability, with no difference in ISQ values. Although, implants with healing chamber demonstrates ascending values in the graph of ISQ, having a trend of faster osseointegration than implants without healing chambers. Both macrogeometries provide a similar primary stability to implants.

TRIAL REGISTRATION

This study was registered retrospectively in ReBec (brazilian registry of clinical trials) under the number RBR-96n5×69, on the date of 19/06/2023.

Efficacy of plasma treatment for surface cleansing and osseointegration of sandblasted and acid-etched titanium implants

PURPOSE

This study was conducted to evaluate the effects of plasma treatment of sandblasted and acid-etched (SLA) titanium implants on surface cleansing and osseointegration in a beagle model.

MATERIALS AND METHODS

For morphological analysis and XPS analysis, scanning electron microscope and x-ray photoelectron spectroscopy were used to analyze the surface topography and chemical compositions of implant before and after plasma treatment. For this animal experiment, twelve SLA titanium implants were divided into two groups: a control group (untreated implants) and a plasma group (implants treated with plasma). Each group was randomly located in the mandibular bone of the beagle dog (n = 6). After 8 weeks, the beagle dogs were sacrificed, and volumetric analysis and histometric analysis were performed within the region of interest.

RESULTS

In morphological analysis, plasma treatment did not alter the implant surface topography or cause any physical damage. In XPS analysis, the atomic percentage of carbon at the inspection point before the plasma treatment was 34.09%. After the plasma treatment, it was reduced to 18.74%, indicating a 45% reduction in carbon. In volumetric analysis and histometric analysis, the plasma group exhibited relatively higher mean values for new bone volume (NBV), bone to implant contact (BIC), and inter-thread bone density (ITBD) compared to the control group. However, there was no significant difference between the two groups (P > .05).

CONCLUSION

Within the limits of this study, plasma treatment effectively eliminated hydrocarbons without changing the implant surface.

Bone-to-Implant Contact in Implants with Plasma-Treated Nanostructured Calcium-Incorporated Surface (XPEEDActive) Compared to Non-Plasma-Treated Implants (XPEED): A Human Histologic Study at 4 Weeks

Titanium implants undergo an aging process through surface hydrocarbon deposition, resulting in decreased wettability and bioactivity. Plasma treatment was shown to significantly reduce surface hydrocarbons, thus improving implant hydrophilicity and enhancing the osseointegration process. This study investigates the effect of plasma surface treatment on bone-to-implant contact (BIC) of implants presenting a nanostructured calcium-incorporated surface (XPEED®). Following a Randomized Controlled Trial (RCT) design, patients undergoing implant surgery in the posterior maxilla received additional plasma-treated (n = 7) or -untreated (n = 5) 3.5 × 8 mm implants that were retrieved after a 4-week healing period for histological examination. Histomorphometric analysis showed that plasma-treated implants exhibited a 38.7% BIC rate compared to 22.4% of untreated implants (p = 0.002), indicating enhanced osseointegration potential. Histological images also revealed increased bone formation and active osteoblastic activity around plasma-treated implants when compared to untreated specimens. The findings suggest that plasma treatment improves surface hydrophilicity and biological response, facilitating early bone formation around titanium implants. This study underscores the importance of surface modifications in optimizing implant integration and supports the use of plasma treatment to enhance osseointegration, thereby improving clinical outcomes in implant dentistry and offering benefits for immediate and early loading protocols, particularly in soft bone conditions.

Clinical efficiency and stability of surface-modified implants: acid modification versus photoactivation

OBJECTIVE

. Aim: To study the stability of surface-modified dental implants, with the usage of sandblasting/acid modification vs. photoactivation.

PATIENTS AND METHODS

Materials and Methods: In the observation were included 164 patients with dental defects. All patients had digital impressions taken by scanning the oral cavity with an intraoral scanner 3Shape TRIOSR. Group A (80 subjects) included implants whose surface was modified with a combination of sandblasting and acid. Group B (84 subjects) - implants after modification with photoactivation. The implant stability quotient was recorded using an Osstell MentorTM device.

RESULTS

Results: The reliable effectiveness of the photoactivation method in complex treatment of the surface of dental implants in improving the stability of fixed dentures in the short and long-term periods of observation was proven. When assessing immediate clinical outcomes, there was no significant difference in the frequency of hyperemia, algesia, hyperthermia, soft tissue edema, regional lymphadenitis, depending on the classical method of treating the implant surface and the complex method with photoactivation. Of the long-term clinical outcomes with classical surface treatment, the absolute risk of implant failure was 1.2%, relative risk - 0,99 [CI%0,96-1,0]. The average value of the implant stability coefficient (ISQ) and the data of the Periotest study at the time of surgery probably did not differ in the observation groups, after 3 months, a higher index was proven in the treatment of the surface by the method of photoactivation and greater stability of the mandibular implants. At the time of implantation, there were no statistically significant differences in implant fixation between the groups, however, during prospective observation in group A, secondary stability indicators based on periotestometry results were significantly lower.

CONCLUSION

Conclusions: It was proved the reliable effectiveness of the photoactivation-method for surface modification in the short and long-term periods of observation for improving the results of orthodontically treatment.

Guidance and rationale for the immediate implant placement in the maxillary molar

Objectives

While the reliability of immediate implant placement in the maxillary molar has been discussed, its significance is questionable. There have been no guidelines for case selection and surgical technique for successful treatment outcomes of immediate maxillary molar implants. Therefore, in this study, we classified alveolar bone height and socket morphology of the maxillary molar to establish guidelines for immediate implant placement.

Materials and Methods

From 2011 to 2019, we retrospectively analyzed 106 patients with 148 immediate implants at the Department of Oral and Maxillofacial Surgery, Seoul National University Dental Hospital. Inclusion and exclusion criteria were applied, and patient characteristics and treatment results were evaluated clinically and radiologically.

Results

A total of 29 tapered, sand-blasted, large-grit, and acid-etched (SLA) surfaces of implants were placed in 26 patients. The mean patient age was 64.88 years. Two implants failed and were reinstalled, resulting in a 93.10% survival rate. Fluctuating marginal bone level changes indicating bone regeneration and bone loss were observed in the first year following installation and remained stable after one year of prosthesis loading, with an average bone loss of 0.01±0.01 mm on the distal side and 0.03±0.03 mm on the mesial side.

Conclusion

This clinical study demonstrated the significance of immediate implant placement in maxillary molars as a reliable treatment with a high survival rate using tapered SLA implants. With an accurate approach to immediate implantation, surgical intervention and treatment time can be reduced, resulting in patient satisfaction and comfort.

Nanostructured Calcium-Incorporated Surface Compared to Machined and SLA Dental Implants-A Split-Mouth Randomized Case/Double-Control Histological Human Study

Background: Implant surface topography is a key element in achieving osseointegration. Nanostructured surfaces have shown promising results in accelerating and improving bone healing around dental implants. The main objective of the present clinical and histological study is to compare, at 4 and 6 weeks, (w) bone-to-implant contact in implants having either machined surface (MAC), sandblasted, large grit, acid-etched implant surface (SLA) medium roughness surface or a nanostructured calcium-incorporated surface (XPEED®). Methods: 35 mini-implants of 3.5 × 8.5 mm with three different surface treatments (XPEED® (n = 16)—SLA (n = 13)—MAC (n = 6), were placed in the posterior maxilla of 11 patients (6 females and 5 males) then, retrieved at either 4 or 6w in a randomized split-mouth study design. Results: The BIC rates measured at 4w and 6w respectively, were: 16.8% (±5.0) and 29.0% (±3.1) for MAC surface; 18.5% (±2.3) and 33.7% (±3.3) for SLA surface; 22.4% (±1.3) and 38.6% (±3.2) for XPEED® surface. In all types of investigated surfaces, the time factor appeared to significantly increase the bone to implant contact (BIC) rate (p < 0.05). XPEED® surface showed significantly higher BIC values when compared to both SLA and MAC values at 4w (p < 0.05). Also, at 6w, both roughened surfaces (SLA and XPEED®) showed significantly higher values (p < 0.05) than turned surface (MAC). Conclusions: Nanostructured Calcium titanate coating is able to enhance bone deposition around implants at early healing stages.

Postsurgical Pain and Implant Osseointegration Failure: A Case Control Study

Aim. The relationship between postsurgical pain and osseointegration was evaluated and analyzed in this study. Material and method. 27 patients, ranging in age from 35 to 72 years old, 12 males and 15 females, who received dental implants and failed to achieve osseointegration from Tianjin Medical University Second Hospital, were analyzed and studied in the following aspects: bone density, initial torque, one- or two-stage surgery, postsurgical pain, postsurgical swelling, and radiographic evidence of osseointegration failure. Result. 5 patients were assessed to be D4 bone density and 7 cases were assessed to be D3 bone density, 2 patients were assessed to be D2 bone density and 13 patients were assessed to be D1 bone density. All cases were documented with clinically acceptable initial torque. Among the 27 cases, 2 of them were one-stage nonsubmerged surgery and 25 cases were two-stage submerged surgery. 25 out of 27 patients reported moderate to severe pain lasting for more than 72 hours. Radiologic examinations failed to offer any indication of poor osseointegration in the 7-day postsurgical follow-up. Conclusion. Moderate to severe postsurgical pain lasting more than 72 hours displays high odd ratio of poor osseointegrate. The radiological examinations alone failed to offer any valuable evidence for the early detection of osseointegration failure in this study.