Intra-osseous anchorage of dental prostheses. I. Experimental studies

Adenovirus mediated gene delivery of α-calcitonin gene-related peptide facilitates osseointegration of implant in ovariectomized rat

Background

Osteoporosis, which adversely affected osseointegration of dental implants, became prevalent with the entry of ageing era. Recent studies indicated that α-calcitonin gene-related peptide (α-CGRP) played a role in modulating osteoporosis. However, due to the plasma half-life of α-CGRP being estimated at merely 7-10 min, it was difficult to utilize a conventional method that administered sufficient α-CGRP to the implant site. This present study aimed to investigate the efficacy of an α-CGRP transgene in promoting implant osseointegration in ovariectomized (OVX) rats.

Method

The osteoporosis rat model was established through bilateral ovariectomy, following which the subjects were categorized into three distinct groups: the α-CGRP transgene group, the empty virus vector group, and the blank control group. Ad-CGRP-EGFP was locally administered into the bone defect site prior to implant placement in the OVX rats. 7 and 28 days after implantation, the femurs were isolated for molecular and histological analyses, micro-CT analysis and biomechanical test.

Result

Bone marrow stromal cells (BMSCs) transduced with Ad-CGRP-EGFP could continuously express α-CGRP more than 28 days in vitro. Successful transgene expression was confirmed through cryosectioning and Western blot analysis 7 days after implantation in vivo. The results indicated a substantial decrease in the quantity of TRAP + cells in the α-CGRP transgene group. Additionally, quantitative real-time RT-PCR and Western blot analysis revealed a significant elevation in the expression levels of Runx2 and ALP, coupled with a notable reduction in the expression of cathepsin K and RANKL (P<0.05). Moreover, the α-CGRP transgene group exhibited a significant enhancement in osteointegration and restoration of implant stability in OVX rats (P<0.01) 28 days after implantation.

Conclusion

This study implied a great therapeutic potential of α-CGRP in osseointegration of titanium implants in OVX-relative osteoporosis rats, offering valuable insights for guiding bone regeneration strategies under osteoporotic conditions.

On design, fabrication, and pre-clinical validation of customized 3D-printed dental implant assembly

In the past few decades, 3D-printed dental implants have been manufactured, and significant studies have demonstrated the pre-clinical validation of such systems. However, studies have yet to tackle the ever-present issue of preventing the jumping gap to enhance overall outcomes. The present study details the utilization of patient computed tomography (CT) data to design and subsequently fabricate a multi-component customized dental implant assembly and customized instruments using direct metal laser sintering (DMLS) technology. The workflow was validated for two patient data sets (cases 1 and 2), which were used to render and print custom implant assemblies; the simulation data for these were compared with a commercially available solution. The present study incorporated a prototype stage as well as subjecting the customized implant assemblies to both static (Case 1: 38.889-77.815 MPa vs 75.47-158.09 MPa; Case 2: 83.947-106.65 MPa vs 55.225-126.57 MPa) and dynamic finite element analysis (Case 1: 41.076-84.09 MPa vs 75.448-187.91 MPa; Case 2: 106.81-108.7 MPa vs 79.176-135.48 MPa) along with resonance frequency analysis (Case 1: 7763.2 Hz vs 7003.6 Hz; Case 2: 7910.1 Hz vs 7102.1 Hz) as well as residual stress analysis. The assembly's stress patterns and resonance frequencies were evaluated against a commercially available implant system. It was observed that the customized implant assemblies tended to outperform the commercially available solution in most simulated scenarios.

A review of the advances in implant technology: accomplishments and challenges for the design of functionalized surface structures

Biomedical implants are extensively utilized to replace hard-tissue defects owing to their biocompatibility and remarkable tissue-affinity. The materials and functional design are selected based on the resultant osseointegration level and resistance to infection, and these considerations constitute the dominant research topic in this field. However, high rates of implantation failure and peri-implantitis have been reported. Current research on biomedical-implant design encompasses enhancement of the implant surface properties, such as the roughness, nano/micro topography, and hydrophilicity, along with the realization of advanced features including antibacterial properties and cell and immunomodulation regulation. This review considers the two achievements of contemporary implant manufacturing; namely, osseointegration and the realization of antibacterial properties. Present mainstream surface modifications and coatings are discussed, along with functional design technologies and achievements. The impacts of direct surface-treatment techniques and osteogenic functional coatings on osseointegration performance and antibacterial surface structures are elucidated, considering inorganic and organic coatings with antibacterial properties as well as antibiotic-releasing coatings. Furthermore, this review highlights recent advancements in physically driven antimicrobial strategies. Expanding upon existing research, future directions for implant studies are proposed, including the realization of comprehensive functionality that integrates osseointegration and antibacterial properties, as well as patient-specific design. Our study presents a comprehensive review and offers a novel perspective on the design of biomedical implants for enhanced versatility. An in-depth exploration of future research directions will also stimulate subsequent investigations.

Clinical effectiveness of Zirconia versus titanium dental implants in anterior region: an overview of systematic reviews

BACKGROUND

Nowadays dental implants are commonly used and to fulfil esthetic demands, zirconia has been suggested as an implant material as an alternative to titanium. Many researchers and systematic reviews are documented on it, but the results have been often inconsistent. This overview of systematic reviews aimed to report on the factors that influence the clinical effectiveness of zirconia (Zi) versus titanium (Ti) dental implants in anterior region.

METHODS

This overview of systematic reviews (Registration Number CRD42023396206) is in accordance with the Transparent Reporting of Systematic Reviews and Meta-analyses. PubMed, Cochrane, Scopus, Embase and Google Scholar databases were sourced for systematic review and meta-analyses. Joanna Briggs Institute (JBI) criteria and Measurement Tool to Assess systematic Reviews" (AMSTAR-2), evaluated the quality. The PICO-focused question of this overview of systematic reviews was "What are the various factors influencing the clinical performance of Zi versus Ti implants in the anterior area?", Evaluations were assessed by two assessors. In case there was any uncertainty or dispute among the reviewers, the work was included for further screening. Using Cohen's kappa, the inter-reviewer reliability was evaluated.

RESULTS

Six reviews were chosen from 57 suitable reviews for this data analysis. Although the survival and effectiveness rates backed titanium implants, there was no conclusive proof of marginal bone loss. Zirconium implants performed better in terms of aesthetics.

CONCLUSION

Clinical performance of zirconia could be considered at par with titanium implants in the anterior area. Titanium has exhibited greater mechanical performance but no significant difference between two recorded. In future, studies with improved design are needed to identify biological and technical factors that affect implant's efficacy.

NOVELTY AND RELEVANCE

This is the first overview of systematic reviews focusing specifically on the anterior region, evaluates both aesthetic and biomechanical performance of Zi and Ti Implants, offers detailed insight into material-specific advantages and limitations. In the present clinical scenario it addresses a critical gap by comparing the performance of Zi and Ti implants and evaluates patient-centred priorities, particularly in the highly visible anterior region.

[Osseointegration in amputation surgery : Representative studies]

Osseointegration is an innovative procedure to improve the mobility and quality of life of amputees by connecting exoprostheses to the bone as a replacement for the conventional socket prosthesis. This article highlights two main approaches: the osseointegrated prosthesis for the rehabilitation of amputees (OPRA) system, which uses a thread-based implant and the integral leg prosthesis (ILP) and osseointegrated prosthetic limb (OPL) systems, which rely on the press-fit method. While osseointegration offers benefits such as better prosthesis fixation and fewer skin problems, there are also challenges, particularly the increased risk of infections. Research and studies have shown that the procedure can substantially improve the quality of life of amputees when used correctly. The systems OPRA, ILP and OPL are analyzed with respect to the effectiveness and complications, noting that complication rates decrease with increasing experience and improved design. Overall, osseointegration represents a promising alternative for amputees who experience discomfort and cannot cope with traditional socket prostheses.

The influence of the superimposition procedure and type of intraoral impression on the superimposition accuracy of CBCT scans with dental impressions in implant planning: an in-vitro study

PURPOSE

The aim of this study was to investigate the superimposition of CBCT data with virtual models of the oral situation directly generated using an IOS and with indirectly generated plaster models.

METHODS

Two different radiopaque jaw models were first scanned using a CBCT unit. Secondly, ten scans using an IOS and ten alginate impressions were made. The alginate impressions were cast with plaster and the plaster models were digitized using a laboratory scanner. Virtual Reference models generated with an industrial scanner were superimposed with the data sets of the virtual models using both a best-fit procedure on the palate and on the teeth. Deviations in two toothless areas were statistically evaluated.

RESULTS

The superimposition of the directly generated models with the CBCT-based datasets showed lower deviations. Lower deviations were also calculated for the best-fit based on the teeth. The lowest deviations were found for model 1 with direct modeling and superimposition over the teeth with 0.008 mm (indirect: 0.210 mm; P = 0.001) and for model 2 with 0.010 mm (indirect 0.106 mm; P = 0.002).

CONCLUSIONS

Virtual models of the oral situation generated directly using an IOS are better suited for superimposing with CBCT-based datasets than indirectly generated ones. The best-fit on the teeth is superior to that on the palate.

Influence of Implant Component Materials on Peri-Implant Soft Tissue Healing: A Comparative Histological and Immunohistochemical Study in Humans

BACKGROUND

Recently, the importance of peri-implant soft tissue integration quality has been recognised as an essential factor in the long-term success of dental implant rehabilitation.

AIM

The aim of this study was to explore the influence of three materials commonly used in implant dentistry, namely titanium (Ti), dental adhesive resin (Re) and polyetheretherketone (PEEK), on the peri-implant soft tissues.

METHODS

In this clinical randomised comparative study, 37 bone-level implants were placed, and experimental transmucosal healing abutments made of different materials were randomly assigned to each implant. These abutments were removed together with the surrounding soft tissues after 8 weeks. Immunohistochemical analyses were performed to determine the presence and localisation of different immune cells. In addition, clinical and radiographic data were collected and peri-implant bone remodeling was assessed.

RESULTS

Compared to the Ti and PEEK groups, Re abutments revealed a higher infiltration of macrophages in the connective tissue (p = 0.04) and neutrophils in the adjacent epithelium (p = 0.03). In the Re abutments, peri-implant bone remodeling was higher compared to the other groups (p = 0.01).

CONCLUSION

The use of resin material as a transmucosal healing abutment should be carefully considered as it was associated with a higher presence of inflammatory cells at 8 weeks post-implantation as well as superior bone remodeling compared to PEEK and Ti.

Randomized, Placebo-Controlled Pilot Study of Naproxen During Dental Implant Osseointegration

OBJECTIVES

Nonsteroidal anti-inflammatory drugs (NSAIDs) are often prescribed following the placement of dental implants, but the effects of these drugs on the osseointegration process are poorly understood. We designed a randomized, placebo-controlled pilot study to quantitatively assess the effect of NSAIDs during early implant osseointegration.

MATERIALS AND METHODS

Subjects receiving a maxillary dental implant were randomized to take naproxen or placebo for 7 days after the surgery. Implant osseointegration was quantified using Resonance Frequency Analysis device. Implant-Stability-Quotient (ISQ) measurement was performed at the time of surgery and at follow-up visits 1, 4, and 16 weeks after surgery. Periapical radiographs were taken to measure the marginal bone level. Separately, a questionnaire of NSAIDs usage was provided to subjects presenting with early implant failure.

RESULTS

After 4 weeks, ISQ values increased modestly ( + 1%) in subjects receiving naproxen whereas subjects receiving placebo had a much larger increase in ISQ value (+41%). We observed 55% more marginal bone loss at 4 weeks, and 52% at 16 weeks in the naproxen group compared to the placebo group. These results were not found to have statistically significant between groups (p ≥ 0.05). These effect sizes and variance were used to conduct a power analysis to determine the necessary sample size for future studies. Furthermore, our separate questionnaire study revealed that 68% of our patients with early failed dental implants reported a history of NSAIDs usage after the surgery.

CONCLUSION

In conclusion, this pilot study provides effect sizes and sample size estimates for future studies to definitively determine recommendations regarding NSAID usage following dental implant surgery. Nonetheless, our study did not observe any statistically significant differences in ISQ value or marginal bone loss after up to 16 weeks of follow-up between subjects from naproxen and placebo groups.

Influence of Implant Geometry on the Surface Strain Behavior of Peri-Implant Bone: A 3D Analysis

To ensure long-term implant success, it is crucial to understand the force transmission from the implant to the surrounding bone. In dentistry, bioengineering methods are applied to investigate these processes. The aim of this study was to analyze the influence of different implant geometries on the surface strain behavior of porcine mandibles under load using a 3D optical camera system in combination with digital image correlation. Four different implant types were subjected to a force of 200 N in three different loading directions (axial, non-axial 15°, and non-axial 30°). Under axial loading, parallel-walled implants exhibited lower surface strain values on the peri-implant bone compared with tapered implants. However, when subjected to non-axial loading, these parallel-walled implants showed a substantial relative increase in strain by approximately a factor of 2.96 compared with axial conditions. At a 30° non-axial angle, long, tapered implants with a smaller diameter (BLX 3.75) produced lower peri-implant bone strains than implants with larger diameters and shorter lengths, while short, tapered implants (BLT) demonstrated a lower relative increase in strain (factor ~1.49) from axial to non-axial loading. Under non-axial loading, long, tapered implants with a small diameter resulted in lower strains in the peri-implant bone compared with implants with a larger diameter and shorter length. It was found that non-axial loads lead to higher strains than axial loads. Therefore, the success of implantation could be significantly influenced by selecting an appropriate implant geometry and the correct angulation of the implant.

A 10-year Retrospective Clinical Study to Identify Risk Indicators for Peri-Implant Bone Loss and Implant Failure

AIM

To evaluate long-term survival and success of dental implants and evaluate indicators affecting the long-term outcome.

MATERIALS AND METHODS

Implant survival, success and crestal bone loss (BL) over time were evaluated. For covariates at patient level, Kaplan-Meier estimates of implant survival were compared between groups with the log-rank test. Observed mean bone loss (MBL) was plotted as a function of time. Cumulative frequencies of BL were plotted for different post-op times. Uni- and multivariate analysis was performed. Simple linear mixed and multiple linear mixed models for BL at 1, 5 and 10 years were fitted.

RESULTS

407 patients (221 women, 186 men; mean age 64.86 years (range 28-92, SD 10.11)), with 1482 implants, responded. Absolute implant survival was 94.74%; MBL was 0.81 mm (SD 1.58, range 0.00-17.00) after an average follow-up of 10.66 years (range 10-14, SD 0.87). Implant survival was influenced on implant level by smoking, implant width and early bone loss (EBL) > 0.5 mm; on patient level by a history of periodontitis. Indicators influencing MBL after the 1st year were abutment height, type of surgery and implant width, while after 5 and 10 years of function were abutment height, EBL > 0.5 mm and smoking.

CONCLUSION

Implant survival was significantly affected by a history of periodontitis on patient level and by smoking, implant width and EBL > 0.5 mm on implant level. Late bone loss was significantly affected by abutment height, EBL > 0.5 mm and smoking.

TRIAL REGISTRATION

B670201524796.

Therapeutic effectiveness of keratinized mucosa augmentation for functioning dental implants: A systematic review and meta-analysis

PURPOSE

This study aimed to provide the latest updates on the therapeutic effectiveness of keratinized mucosa (KM) augmentation using autogenous soft tissue grafts for dental implants retaining prostheses.

STUDY SELECTION

A systematic search of electronic databases was conducted on autogenous soft tissue grafts to create and/or augment KM for functioning dental implants. Two investigators independently extracted data from the selected 11 clinical studies, including 290 participants, from the initially retrieved 573 publications.

RESULTS

A lack of KM surrounding dental implants was associated with greater mucosal inflammation. A free gingival graft (FGG) was used to increase the KM width, and a connective tissue graft (CTG) was used to manage peri-implant mucosal recession (MR). The weighted mean gain in KM was 2.6 mm from the selected FGG studies, with a significant reduction in mucosal inflammation and no changes in crestal bone levels for up to 4 years. The weighted mean reduction in MR was 2 mm in selected CTG studies.

CONCLUSIONS

A lack of KM negatively affects soft tissue health around dental implants. FGG was effective in increasing KM and reducing mucosal inflammation, whereas CTG was effective in decreasing MR.

Optimizing orthodontic anchorage: comparative evaluation of larger diameter, shorter length mini-implants for enhanced mechanical stability

AIM

We aim to assess and contrast the mechanical stability of two mini-implant designs, featuring larger diameters and shorter lengths, for orthodontic anchorage against a conventional group of implants.

Immediate Loading and Implant Placement With Bone Grafting in Severely Proclined Anterior Mobile Teeth in the Esthetic Zone: A Report of an Intriguing Case

Achieving success in dental implant therapy within the esthetic zone involves not only ensuring that the implant properly integrates with the surrounding bone but also achieving a visually pleasing outcome. It is challenging to create a seamless and balanced appearance of the gums around the implant, in harmony with the natural teeth nearby. To replace a missing tooth in the esthetic zone, immediate implant placement and provisionalization, a meticulously researched and dependable method, have received recognition as a predictable technique demanding fewer surgical procedures. This case report demonstrates how to replace failing upper central and lateral incisors while maintaining the gum esthetics by using immediate implant placement and provisionalization. In order to reduce trauma to both soft and hard tissues, the upper right and left central and lateral incisors were extracted without elevating the gum flap. Subsequently, a dental implant was promptly inserted using a surgical guide with bone graft and furnished with a provisional crown that did not contact the opposing teeth. Throughout the healing period, no notable negative effects were observed in both clinical assessments and X-rays. This proposed treatment approach offered the patient immediate improvements in esthetics, functionality, and comfort without encountering any complications.

The research status and future direction of polyetheretherketone in dental implant -A comprehensive review

Currently, dental implants primarily rely on the use of titanium and titanium alloys. However, the extensive utilization of these materials in clinical practice has unveiled various problems including stress shielding, corrosion, allergic reactions, cytotoxicity, and image artifacts. As a result, polyetheretherketone (PEEK) has emerged as a notable alternative due to its favorable mechanical properties, corrosion resistance, wear resistance, biocompatibility, radiation penetrability and MRI compatibility. Meanwhile, the advancement and extensive application of 3D printing technology has expanded the range of medical applications for PEEK, including artificial spines, skulls, ribs, shinbones, hip joints, and temporomandibular joints. In this review, we aim to assess the advantages and disadvantages of PEEK as a dental implant material, summarize the measures taken to address its shortcomings and their effects, and provide insight into the future potential of PEEK in dental implant applications, with the goal of offering guidance and reference for future research endeavors.

The Impact of Socket Shield and Implant Surface Modification With Platelet-Derived Growth Factor on Osseointegration

Implants have become the first treatment option in the anterior esthetic region. Buccal bone loss is the sequalae of tooth extraction compromising osseointegration and cosmetic goals. The present case report is of a 47-year-old female who requested to have her fractured central incisor replaced with fixed restoration supported by an implant; the tooth had already undergone a root canal and lacked a sufficient structure for crown prosthesis placement. This case report evaluates the efficacy of the socket shield technique (SST) combined with a coating of recombinant human platelet-derived growth factor-BB (rhPDGF-BB) on the implant surface to achieve optimal biomechanical stability and esthetics.

The biomechanical principles of restoring a dentition with dental implants: A General Dental Practitioner's perspective

Dental implants continue to increase in popularity as a method of replacing missing or failing teeth and, in doing so, this increased prevalence is likely to present as a range of scenarios for the general dental practitioner and dental hygienist, whether they have an interest in the field or not. Many of these scenarios will relate to the restorative and post-treatment phases of treatment, where the biomechanical performance of the restoration will need to be understood by the treating clinician in the primary care setting. This article aims to highlight the unique biomechanical nature of dental implant restorations, the differences between a natural tooth held by periodontal ligament fibres and a dental implant ankylosed to bone, the consideration of restoring a natural tooth opposing a dental implant, and the long-term effect of changes in the occlusion and their impact on previously placed dental implant restorations.

Per-Ingvar Brånemark (1929-2014): A Homage to the Father of Osseointegration and Modern Dentistry

Dr. Professor Per-Ingvar Brånemark (Branemark), a Swedish professor of anatomy, is widely acknowledged as a pioneer in modern implant dentistry. His accidental discovery of the strong bond between titanium and bone, which he named "osseointegration," signifies a revolutionary progression in dentistry. This significant contribution has earned him global recognition among scholars and the general public. His work, which spans across disciplines, has introduced a new era of implant reconstruction and fostered the formulation of principles rooted in bone biology. This interdisciplinary advancement has paved the way for diverse craniofacial and orthopedic applications, including facial prostheses and limb replacements, owing to titanium's biocompatibility within the human body. This article stands as a tribute to Brånemark and his remarkable innovation. Despite not being a dentist, Brånemark, an orthopedic surgeon, has left an enduring legacy in dental implantology that continues to impact the field today and will undoubtedly do so in the future, deserving lasting recognition.

Laminin 332 functionalized surface improve implant roughness and oral keratinocyte bioactivity

Objective

The biological seal (BS) at the implant-tissue interface is essential for the success of dental implants (DIs), and the absence of a proper BS can lead to peri-implantitis. The basement membrane (BM) and junctional epithelium are critical for sealing the peri-implant mucosa, and laminin 332 is an important protein in binding the epithelium to the implant surface. The aim of this study was to evaluate the response of oral keratinocytes to titanium dental implant surfaces biofunctionalized with laminin 332.

Design

The dental implant surface was treated with a piranha solution to create hydroxyl (OH) groups, facilitating biofunctionalization with laminin 332. The modified surface underwent scanning electron microscopy, surface roughness evaluation, and chemical composition analysis. Human keratinocytes from the Cal-27 line were then cultured on the modified implants for 24 and 48 h to assess viability, morphology, cytokine secretion, and mRNA expression of tissue repair-associated genes.

Results

The results showed that laminin 332 biofunctionalization of the implant surface resulted in lower values of Ra, Rq and positive surface roughness parameters Rsk, Rku and Rv. The elemental composition showed an increase in nitrogen and carbon content corresponding to protein binding. The biofunctionalized surfaces did not affect cell viability and promoted cytokine secretion (IL-1a and IL-8) and a significant increase (p < 0.05) in MCP-1, EGF, FGF, TGF and VEGF gene expression compared to the control.

Conclusion

In conclusion, laminin 332 coating Ti implants was shown to be effective in promoting keratinocyte adhesion, spreading, and viability. This approach could be an alternative way to improve biocompatibility.

Investigation of the impact of planar microelectrodes on macrophage-mediated mesenchymal stem cell osteogenesis

Osseointegration commences with foreign body inflammation upon implant placement, where macrophages play a crucial role in the immune response. Subsequently, during the intermediate and late stages of osseointegration, mesenchymal stem cells (MSCs) migrate and initiate their osteogenic functions, while macrophages support MSCs in osteogenesis. The utilization of ferroelectric P(VDF-TrFE) covered ITO planar microelectrodes facilitated the simulation of various surface charge to investigate their effects on MSCs' osteogenic differentiation and macrophage polarization and the results indicated a parabolic increase in the promotional effect of both with the rise in piezoelectric coefficient. Furthermore, the surface charge with a piezoelectric coefficient of -18 exhibited the strongest influence on the promotion of M1 polarization of macrophages and the promotion of MSCs' osteogenic differentiation. The impact of macrophage polarization and MSC osteogenesis following the interaction of macrophages affected by surface charge and MSC was ultimately investigated. It was observed that macrophages affected by the surface charge of -18 piezoelectric coefficient still exerted the most profound induced osteogenic effect, validating the essential role of M1-type macrophages in the osteogenic differentiation of MSCs.

Targeted muscle reinnervation in bionic upper limb reconstruction: current status and future directions

Selective nerve transfers are used in the setting of upper limb amputation to improve myoelectric prosthesis control. This surgical concept is referred to as targeted muscle reinnervation (TMR) and describes the rerouting of the major nerves of the arm onto the motor branches of the residual limb musculature. Aside from providing additional myosignals for prosthetic control, TMR can treat and prevent neuroma pain and possibly also phantom limb pain. This article reviews the history and current applications of TMR in upper limb amputation, with a focus on practical considerations. It further explores and identifies technological innovations to improve the man-machine interface in amputation care, particularly regarding implantable interfaces, such as muscle electrodes and osseointegration. Finally, future clinical directions and possible scientific avenues in this field are presented and critically discussed.

Role of Polyetheretherketone in Prosthodontics: A Literature Review

Implant prostheses and other fixed and removable metal prostheses have led to an increase in demand for the development of new and efficient materials such as high-performance polymers polyetheretherketone (PEEK) over titanium and other metals because of their further complications in the human body. PEEK is a polymer that is nontoxic and has a modulus of elasticity that is comparable to that of human bone. PEEK implants provide benefits over metal implants, such as reducing the stress shielding effect, simple processing, and color resemblance to natural teeth. And it is a fantastic alternative to titanium for dental and orthopedic implants. The current review is undertaken to understand the properties of this PEEK material to weigh its benefits and drawbacks for potential use in dental implants and other prostheses.

An introduction to dental implants

The use of implants to replace missing teeth is now commonplace and practised by clinicians worldwide in both general and specialist practice. There is an abundance of evidence on the general success of implant treatment. As well as reviewing the history of dental implants, this narrative review will discuss the merits and successful placement of tissue-level verses bone-level implants. Furthermore, the article will evaluate the concept and benefits of platform switching for implant treatment. Finally, with the increased placement of implants, this narrative paper will review how different titanium surfaces impact on the risk of peri-implantitis.

Jumping gap in immediate implant placement in the esthetic zone: A virtual implant planning using cone-beam computed tomography

PURPOSE

A jumping gap (JG) refers to the implant's future buccal wall; this study aims to estimate the jumping gap dimension in relation to virtual implant placement and subsequently link the implant diameter and implant position with the anatomical site.

METHODS

This observational study was conducted to analyze the maxillary teeth in the esthetic zone from cone-beam computed tomography (CBCT) scans using OnDemand software. The horizontal jumping gap dimension of each tooth was assessed by subtracting the calculated virtual implant diameter from the socket dimensions.

RESULTS

A total of 253 anterior and premolar maxillary teeth were analyzed from 52 CBCT scans. The estimated JG dimensions were 1.23 ± 0.59 mm, 1.80 ± 0.64 mm, 3.02 ± 0.69 mm, for central incisors, lateral incisors and canines respectively, 3.70 ± 0.68 mm for the first premolars showing the highest horizontal gap and 3.19 ± 0.88 mm for second premolars. The incisors showed the smallest horizontal gap compared to the canines and premolars.

CONCLUSIONS

In terms of JG, immediate implant placement is more favorable at the canine and premolar sites. By contrast, the incisors sites should be handled with extreme caution, where the use of narrower implants is advisable when necessary.

Comparative Analysis of Surface Modification Techniques for Assessing Oral Implant Osseointegration: An Animal Study

BACKGROUND

Effective implant placement depends critically on the implant's level of osseointegration with the alveolar bone. To increase osseointegration during implant placement, research has concentrated on the surface modification of implants, and morphological analyses have looked at the thread pattern in close interaction with the bone's surface.

AIM

This study aimed to assess and compare the extent of oral implant osseointegration in different surface modification techniques.

MATERIALS AND METHODS

In this study, 12 healthy adult dogs aged 18-24 months were used. Tooth extractions were performed on both sides of the mandible, and wounds were closed with sutures. Two months later, the right mandible of each dog underwent local anesthesia and general anesthesia. Four different implant types were placed based on their surface treatments: resorbable blast media (RBM)-treated implants, hydroxyapatite (HA) implants with an ultra-thin HA film, hydrothermal-treated HA implants coated with HA, and sandblasting combined acid etching (SLA) implants treated with plasma spray and acid etching. A total of 48 implants were divided into two- and four-week groups, with identical dimensions. Each dog received two implants from each group, for a total of eight implants per dog. The implants were securely placed into the superior alveolar bone with a torque greater than 35-N up to a depth of 1 mm. Periotest M (Medizintechnik Gulden e.K., Modautal, Germany) was used to calculate the periotest value (PTV) as a typical value on the buccal side of each implant immediately following placement and sacrifice to test the main fixation and stability of the implants. Resonance frequency analysis (RFA) was utilised by Osstell Mentor (Osstell AB, Gothenburg, Sweden) to simultaneously assess the implant stability quotient (ISQ) on the medial, distal, buccal, and lingual sides of the implant. The rotational torque in one of the sacrificed dogs was calculated using the MGT 50 (ELECTROMATIC Equipment Co., Inc., New York, USA) torque analyzer. The histomorphometric evaluation was performed using an optical microscope (Olympus Corporation, Tokyo, Japan). The upper half's bone-implant contact (BIC), which was found to be more important for implant stability, was studied together with the ratio of the new bone formation area (NBFA) to the complete implant.

RESULTS

The maximum stability was observed in HA-treated implants in the fourth week. The minimum stability was observed in hydrothermal-treated HA implants in the fourth week. The stability in each group was greater in the four-week evaluation as compared to the two-week evaluation. The stability was satisfactory in almost all implants at two- and three-week evaluations. The maximum value of the percentage area of newly formed bone at the two- and four-week evaluations was observed in HA-treated implants. The minimum value of the percentage of the area of newly formed bone at two- and four-week evaluations was observed in SLA and RBM-treated implants respectively. The difference was significant statistically (p ≤ 0.05).

CONCLUSION

All implant surface modifications, in general, produced satisfactory osseointegration. Excellent osseointegration was seen in the upper portion of the implant with hydrothermally treated HA.

Fatigue properties of plasma nitriding for dental implant application

STATEMENT OF PROBLEM

Fatigue failure of implant components is a common clinical problem. Plasma nitriding, an in situ surface-strengthening method, may improve fatigue properties of dental implants.

PURPOSE

The purpose of this in vitro study was to evaluate the effect of plasma nitriding on the fatigue behavior of implant systems.

MATERIAL AND METHODS

The preload and friction coefficient of plasma nitrided abutment screws, as well as settlement of the implant-abutment interface, were measured. Then, the reverse torque values and pullout force were evaluated after cyclic loading. Finally, the fatigue properties of the implant system were investigated with static fracture and dynamic fatigue life tests, and the morphology of the fracture on the surface of the implant system was observed.

RESULTS

The plasma nitriding treatment reduced the friction coefficient; increased the preload, settlement value, reverse torque values, pullout force, and static fracture load; and prolonged fatigue life. Furthermore, abutment screws with plasma nitriding treatment showed a different fatigue fracture mode.

CONCLUSIONS

Plasma nitriding improved mechanical performance and may be a suitable way to optimize the fatigue behavior of dental implants.

Immune dysregulation and macrophage polarization in peri-implantitis

The term "peri-implantitis" (peri-implantitis) refers to an inflammatory lesion of the mucosa surrounding an endosseous implant and a progressive loss of the peri-implant bone that supports the implant. Recently, it has been suggested that the increased sensitivity of implants to infection and the quick elimination of supporting tissue after infection may be caused by a dysregulated peri-implant mucosal immune response. Macrophages are polarized in response to environmental signals and play multiple roles in peri-implantitis. In peri-implantitis lesion samples, recent investigations have discovered a considerable increase in M1 type macrophages, with M1 type macrophages contributing to the pro-inflammatory response brought on by bacteria, whereas M2 type macrophages contribute to inflammation remission and tissue repair. In an effort to better understand the pathogenesis of peri-implantitis and suggest potential immunomodulatory treatments for peri-implantitis in the direction of macrophage polarization patterns, this review summarizes the research findings related to macrophage polarization in peri-implantitis and compares them with periodontitis.

Clinical application of a positioning annular gingival cutter in minimally invasive stage II implant surgery

BACKGROUND

Dental implant restoration is an effective therapy for missing teeth and is widely used in clinical practice to provide more treatment options for patients.

OBJECTIVE

To explore the application of a positioning annular gingival cutter in minimally invasive stage II implant surgery and to evaluate its clinical effects.

METHOD

Stage II implant surgery using a positioning annular gingival cutter was performed on 15 selected patients at 15 implant sites with sufficient keratinized gingival width in the posterior region. The patient underwent crown restoration 2 weeks after surgery and returned for follow-up 3 months later. The surgical effects were recorded for each patient, including the duration of surgery, postoperative pain and swelling, keratinized gingiva width, probing depth (PD) measurements, and the percentage of bleeding on probing (BOP) before surgery, during crown restoration, and 3 months after crown restoration. The data were subjected to a paired sample t-test using Statistical Product and Service Solutions (SPSS) 25.0.

RESULTS

The duration of stage II implant surgery using a positioning annular gingival cutter was 9.23 ± 1.63 min, and the duration of postoperative pain and swelling was 0.73 ± 0.35 and 0.81 ± 0.35 d, respectively. The keratinized gingiva width was 2.93 ± 0.41 mm before surgery and 2.91 ± 0.46 mm after crown restoration, demonstrating no significant reduction (P> 0.05). The keratinized gingiva width remained stable 3 months after crown restoration, with an average of 2.85 ± 0.49 mm, without significant reduction (P> 0.05). No obvious inflammation is observed. PD was 2.60 ± 0.52 mm and BOP was 10%.

CONCLUSION

The use of a positioning annular gingival cutter in stage II implant surgery achieves a positive and stable clinical effect within a short time.

Survival and Success of Dental Implants in Patients with Autoimmune Diseases: a Systematic Review

Objectives

The purpose of this systematic review is to disclose the impact of autoimmune diseases and their medical treatment on dental implant survival and success.

Material and Methods

A literature search was conducted using MEDLINE (PubMed), The Cochrane Library and Embase up to December 6th, 2021. Any clinical study on patients with an autoimmune disease in whom implant therapy was performed was eligible. The quality of included studies was assessed using the Newcastle-Ottawa Scale. For each autoimmune disease group, data synthesis was divided into three groups: 1) overall results of the autoimmune disease, 2) overall results of corresponding control groups and 3) overall results of the autoimmune disease with a concomitant autoimmune disease (a subgroup of group 1). Descriptive statistics were used.

Results

Of 4,865 identified articles, 67 could be included and mainly comprising case reports and retrospective studies with an overall low quality. Implant survival rate was 50 to 100% on patient and implant level after a weighted mean follow-up of 17.7 to 68.1 months. Implant success was sporadically reported. Data on immunosuppressive medication were too heterogeneously reported to allow detailed analysis.

Conclusions

Overall, a high implant survival rate was reported in patients with autoimmune diseases. However, the identified studies were characterized by a low quality. No conclusions could be made regarding implant success and the effect of immunosuppressants due to heterogeneous reporting.

Osseointegration and osteoimmunology in implantology: assessment of the immune sustainability of dental implants using advanced sonographic diagnostics: research and case reports

OBJECTIVE

Bone marrow defects of the jaw (BMDJ) surrounding dental implants, in combination with impaired bone-to-implant contact (BIC), are difficult to detect in X-rays. This study evaluated BMDJ surrounding titanium (Ti-Impl) and ceramic (Cer-Impl) dental implants and incomplete BIC using a new trans-alveolar ultrasonography device (TAU) with numerical scaling for BIC.

METHODS

The titanium stimulation test (Ti-Stim) was used to detect immune overactivation in response to titanium. Bone density surrounding implants was measured using TAU. We also validated osteoimmune dysregulation.

RESULTS

TAU values showed reduced BIC and decreased osseointegration for Ti-Impl. Moreover, TAU values in the Cer-Impl group were more than twice those in the Ti-Impl cohort. The multiplex analysis of C-C motif chemokine 5 (CCL5, also known as RANTES) expression revealed a 20-fold increase in BMDJ surrounding Ti-Impl. Higher levels of CCL5 inflammation were present in the positive Ti-Stim group.

CONCLUSIONS

Our data indicate that Cer-Impl have an osteoimmune advantage over Ti-Impl. The key determinant for osteoimmune sustainability appears to be the absence of inflammation at the implant site. We therefore recommend the use of TAU to assess the implant site prior to implantation.

Qualitative Analysis of the Lived Experience of Individuals After Undergoing Osseointegration for Transfemoral Amputation

Objective

The purpose of this study was to qualitatively assess the first-hand lived experiences of patients with amputation who had transitioned from a traditional socket (TS) to Osseointegration (OI) to impact their overall quality of life (QOL) and function.

Methods

This was a qualitative phenomenological study. Participants who had a unilateral transfemoral amputation and fit the study's inclusion criteria were interviewed in a semi-structured format regarding their quality of life and function before and after transitioning from a traditional socket (TS) to Osseointegration (OI). Responses were then analyzed through line-by-line coding to determine themes that were relevant to QOL outcomes for this study.

Results

Eleven participants were interviewed in this study. The qualitative analysis demonstrated an emergence of 6 main themes consisting of "Improved Quality of Life," "Supportive Community," "Previous Ill-fitting Socket," "Greater Function," "Improved Osseo-perception," and "Promotion of Community Accessibility". Strengths included the use of an OI-specific quality of life assessment with adapted questions from validated outcome measures, international participants, and use of thematic analysis for data analysis. Weaknesses included sample size, niche participant population, and OI as a revision procedure only. More research is still necessary to explore/determine the benefits and detriments of Osseointegration as an alternative to traditional sockets for prosthetic devices.

Conclusion

Individuals who have undergone Osseointegration procedure discuss being more satisfied with their prosthesis and quality of life when compared to their previous experience of a traditional socket.

Impact Statement

This is a first of its kind study reporting on the lived experiences of those who have undergone OI. The field of amputation rehabilitation is expanding rapidly and knowing how this procedure impacts quality of life is important for healthcare professionals to understand as new frontiers are explored in this field.

Association of Age, Gender, and Site of Implant Placement: An Institution-Based Retrospective Study

Tooth loss is an undesirable condition that leads to functional, esthetic and social damage, having an impact on an individual's quality of life. Dental implants are man-made tooth root replacements that are increasingly used to replace a missing tooth. It is important to gather demographic data in order to take precautions before the possible failures. Hence the objective of this study was to retrospectively determine the association between age, gender, and site of implant placement in patients reporting to a private dental institution. This study was carried out from the data obtained from the case records of 1281 patients who had undergone implant therapy. Chi-square test was applied to see associations of gender, age and implant site. The results show that a maximum number of 348 implants (27.7%) were placed in patients aged between 41-50 years. The patient pool consisted of 705 (55%) females and 576 (45%) males. A maximum of 228 implants (17.80%) were placed in region 46 and 224 implants (17.49%) in region 36. Only 2 implants (0.2%) were placed in region 41. There was a positive association between age, gender and site of implant. In those aged 20-30 years, 20.53% of implants were placed, 26.23% in 31-40 years, 27.1% in 41-50 years, 17.95% in 51-60 years and 8.11% in 61-70 years of age. In male, a maximum of 124 implants (54.4%) were placed in region 46 and only 1 implant (50%) in region 41. In females, region 36 had a maximum of 110 implants (49.1%), and the least number of implants were placed in regions 31 and 41. In this study, it can be concluded that general factors such as age and gender had a significant effect on the site of implant placement.

Analysis of risk factors for early crestal bone loss in osseointegrated, submerged implants prior to restoration

BACKGROUND

Evidence on the etiology behind bone loss around submerged, prosthetically nonloaded implants is still limited. The long-term stability and success of implants with early crestal bone loss (ECBL), especially when placed as two-stage implants, is uncertain. Hence, the aim of this retrospective study is to analyze the potential patient-level, tooth- and implant-related factors for ECBL around osseointegrated, submerged implants, before restoration as compared with healthy implants with no bone loss.

METHODS

Retrospective data were collected from patient electronic health records between 2015 and 2022. Control sites included healthy implants with no bone loss and test sites included implants with ECBL, both of which were submerged. Patient, tooth and implant level data were collected. ECBL was assessed using periapical radiographs obtained during implant placement and second-stage surgeries. Generalized estimating equation logistic regression models were used to account for multiple implants within patients.

RESULTS

The total number of implants included in the study was 200 from 120 patients. Lack of supportive periodontal therapy (SPT) was shown to have nearly five-times higher risk of developing ECBL and was statistically significant (p < 0.05). Guided bone regeneration (GBR) procedures before implant placement had a protective effect with an odds ratio of 0.29 (p < 0.05).

CONCLUSIONS

Lack of SPT was significantly associated with ECBL, while sites that received GBR procedures prior to implant placement were less likely to exhibit ECBL. Our results underscore the importance of periodontal treatment and SPT for peri-implant health, even when the implants are submerged and unrestored.

Guided bone regeneration in implant dentistry: Basic principle, progress over 35 years, and recent research activities

Bone augmentation procedures are frequent today in implant patients, since an implant should be circumferentially anchored in bone at completion of bone healing to have a good long-term stability. The best documented surgical technique to achieve this goal is guided bone regeneration (GBR) utilizing barrier membranes in combination with bone fillers. This clinical review paper reflects 35 years of development and progress with GBR. In the 1990s, GBR was developed by defining the indications for GBR, examining various barrier membranes, bone grafts, and bone substitutes. Complications were identified and reduced by modifications of the surgical technique. Today, the selection criteria for various surgical approaches are much better understood, in particular, in post-extraction implant placement. In the majority of patients, biodegradable collagen membranes are used, mainly for horizontal bone augmentation, whereas bioinert PTFE membranes are preferred for vertical ridge augmentation. The leading surgeons are using a composite graft with autogenous bone chips to accelerate bone formation, in combination with a low-substitution bone filer to better maintain the augmented bone volume over time. In addition, major efforts have been made since the millenium change to reduce surgical trauma and patient morbidity as much as possible. At the end, some open questions related to GBR are discussed.

Surveillance study on the application of titanium and its alloys to removable dental prostheses

This review describes individual studies of removable dental prostheses, evaluated their performance and clinical applicability for the proposal to expand health insurance coverage of titanium and its alloys to removable dental prostheses. Titanium and its alloys have become clinically applicable as prosthetic materials by improving dental casting systems. They have high biosafety and good mechanical properties, are excellent substitutes for the silver-palladium-gold alloys for casting, and are highly useful for removable dental prostheses. Therefore, the introduction of health insurance coverage for removable dental prostheses made of titanium and its alloys is worthy of consideration.

Escherichia coli Cellular Activity and Frontal Trizonal Evaluation of Microspace Between Implants and Abutments Under Calibrated Cyclic Stress

AIM

To evaluate microspace and microleakage between implant and abutments subjected to pre- and post-calibrated cyclic stress.

MATERIALS AND METHODS

Twelve screw-retained implant prostheses with BioHPP polyetheretherketone (PEEK) abutment (Noris Dental Implant System Ltd., Nesher, Israel) (Group I) and 12 screw-retained implant prostheses with computer-assisted design/computer-assisted manufacturing (CAD/CAM) milled zirconia abutment (DentGallop, Houston, TX, USA) (Group II) were connected to their respective implant, and the prosthetic screw was torqued to 30N/cm (Noris). The microspace was evaluated using scanning electron microscopy (SEM; TeScan, Brno, Czech Republic). Twenty-four samples were then induced to cyclic stress (Lokesh Industries, Pune, India) simulating 180 days duration of oral stress. The microspaces (Group IA and Group IIB) were measured post-cyclic stress. Group I and II were again renamed into Group Ia and Group IIb for microbial study. Both implant assemblies were immersed in fresh soybean casein digest broth (SCDB) (Himedia, Mumbai, India) and subsequently inoculated with 1.0µL E. coli suspension (Himedia) at the open end and incubated at 37ºC for seven days. After the incubation period, cellular activity was determined by the spread plate method, and total colony-forming units (CFU) were calculated. The results were evaluated using independent T and Mann-Whitney tests.

RESULT

Average and microspace at the implant-abutment junction of Group I samples in the front right was 12.98µm, center 13.76µm, front left 13.22µm, and in Group II samples, the front right was 18.52µm, center 17.84µm, front left 18.58µm.After being subjected to cyclic loading, the mean levels of the vertical microgap for Group IA samples were: in the front right region 10.37µm, in the center 9.34µm, in the front left 10.51µm and in Group IIB samples front right was 14.59µm, center 13.39µm, front left 13.8µm. Independent t-tests showed insignificant differences between the two groups. The median value of microbial leakage of Group Ia samples after cyclic loading was 30 x 103 CFU/ml, and Group IIb samples were 42 x 103 CFU/ml and were significant.

CONCLUSION

There was minimal variation in the mean microspace between the BioHPP PEEK abutment and CAD/CAM milled zirconia abutment, and it was insignificant before and after cyclic stress. BioHPP PEEK abutment-titanium implant interfaces showed significantly decreased microbial leakage than CAD/CAM milled zirconia abutment-titanium implant interfaces after cyclic stress.

Implant connection and abutment selection as a predisposing and/or precipitating factor for peri-implant diseases: A review

Peri-implant mucosal integration is becoming a critical aspect for long term implant health and can be triggered the selection of implant components. The aim of this review is therefore to investigate the evidence concerning implant connection and abutment characteristics (abutment materials, design, handling) as predisposing or precipitating factor for peri-implant mucositis and peri-implantitis. Although the evidence that these features can directly predispose/precipitate peri-implant diseases is limited, there are -few- studies showing a potential role of the implant connection, trans-mucosal configuration, and handling in the development of early bone loss and/or peri-implantitis. With bone level implants, conical internal connections (with inherent platform switching) might be preferred over internal flat-flat and external connections to decrease the risk of early bone loss and potentially the risk of peri-implant disease. Moreover, there is a trend suggesting moving the prosthetic interface coronally (to the juxta-mucosal level) as soon as possible to reduce the number of disconnections and to limit the risk of cements remnants. This can be achieved by choosing a tissue-level implant or to place a trans-mucosal abutment (one abutment-one time approach) to optimize the peri-implant soft tissue seal. In absence of evidence for the biocompatibility regarding several restorative materials, biocompatible materials such as titanium or zirconia should be preferred in the trans-mucosal portion. Finally, higher implants (≥2mm) with an emergence angle below 30° seem more favourable. It should however be noted that some of this information is solely based on indirect information (such as early bone loss) and more research is needed before making firm recommendations about abutment choice. [Correction added on 13 March 2023, after first online publication: 'longer implants (≥2mm)' was changed to 'higher implants (≥2mm)' in this version.].

Increasing the margin of patient safety for periodontal and implant treatments: The role of human factors

Early complications following periodontal and dental implant surgeries are typically attributed to technique or poor biological response, ignoring the possibility of the human element. Interestingly, significant experience is not correlated with increased success, whereas evidence supports the impact of clinical behavior on patient outcome. This is the result of errors, much like those scrutinized in other high-risk technical fields, such as aviation. What can be surprising is that those who make these errors are very well acquainted with best practices. Given this, how is it possible for the conscientious practitioner to fail to apply protocols that are nonetheless very well known? Recently, the concepts of human and organizational factors have been translated to medicine, though dentistry has been slow to recognize their potential benefit. This review lists specific human factor behaviors, such as use of checklists and crew resource management, which might improve postsurgical outcome.

Plasma Electrolytic Oxidation for Dental Implant Surface Treatment

Current technologies of plasma electrolytic oxidation (PEO) for modifying the surfaces of dental implants made of the Grade IV titan alloy provide predictable long-term results in implant dentistry. The aim of the study is to evaluate the efficacy of PEO technology comparing two types of surface modification of dental implants made of VT1-0 medical titanium alloy.

Materials and Methods

50 IRIS dental implants (Scientific Production Company LICOSTOM, Russia), 10-mm long and 4 mm in diameter, were manufactured from the VT1-0 alloy. The implant surface was treated by two PEO methods: 1) in the aqueous solution of alkaline electrolyte without any additional modifiers (PEO-Ti); 2) in the aqueous solution of orthophosphoric acid-based electrolyte containing calcium carbonate (PEO-Ca). Implants made of VT1-0 alloy after milling and without additional treatment served as control samples. The implant surfaces were studied by electron microscopy and energy dispersive X-ray spectrometry. Some of the implants were installed in sheep, samples were obtained at 2, 4, and 8 weeks and studied by microcomputer tomography.

Results

Regardless of the electrolyte composition, a highly developed porous surface was formed in the samples with PEO-modified surfaces. The surface of the PEO-Ti samples in a simple unmodified electrolyte was characterized by a large number of open pores with a wide range of size distribution from 200 nm to 3 μm. The pore size distribution was of a monomodal character, with a maximum near 0.23 μm. The PEO samples in the Ca-containing electrolyte had pores also in a wide range from ~80 nm to ~7 μm. The pore distribution, in contrast to PEO-Ti, was bimodal in nature, with the main maximum in the region of 1.05 μm and the concomitant maximum near 2.45 μm.The obtained surfaces of both types (PEO with Ca and Ti) possessed high purity and optimal microroughness for osseointegration. Both types of PEO treatment (PEO with Ca and Ti) have demonstrated a similar osseointegrative potential, nevertheless, the surface of the PEO-Ca showed a better contact with the implant surface (49.8%) than PEO-Ti (42.4%) obviously due to the presence of calcium in its composition.

Conclusion

The PEO-formed implant surfaces demonstrate high osseointegrative properties after any variants of treatment and show the potential for application in osteoporosis.

Healing of Endosseous Implants Having Different Surface Characteristics in the Alveolar Bone: A Clinical Study

Background Total treatment time in implant placement can be significantly reduced by placing immediate implants into the freshly extracted sockets. Also, immediate implant placement can act as a guide for proper and accurate implant placement. Additionally, in immediate implant placement, the resorption of bone associated with the healing of the extraction socket is also reduced. This clinical study aimed to clinically and radiographically assess the healing of endosseous implants having different surface characteristics in nongrafted and grafted bone. Methodology In 68 subjects, 198 implants were placed, including 102 oxidized (TiUnite, Göteborg, Sweden) and 96 turned surface implants (Nobel Biocare Mark III, Göteborg) were placed. Survival was considered with clinical stability and acceptable function with no discomfort and no radiographic or clinical signs of pathology/infection. Rest cases that showed no healing and implant no osseointegration were considered failures. Clinical and radiographic examination was done by two experts after two years of loading based on bleeding on probing (BOP) mesially and distally, radiographic marginal bone levels, and probing depth (mesial and distal). Results Five implants failed in total where four implants were with the turned surface (Nobel Biocare Mark III) and one was from the oxidized surface (TiUnite). The one oxidized implant was in a 62-year-old female and was placed in the region of mandibular premolar (44) of length 13 mm and was lost within five months of placement before functional loading. Mean probing depth had a nonsignificant difference between oxidized and turned surfaces with the mean values of 1.6 ± 1.2 and 1.5 ± 1.0 mm, respectively, with P = 0.5984; mean BOP in oxidized and turned surfaces was 0.3 ± 0.7 and 0.4 ± 0.6, respectively (P = 0.3727). Marginal bone levels, respectively, were 2.0 ± 0.8 and 1.8 ± 0.7 mm (P = 0.1231). In marginal bone levels related to implant loading, a nonsignificant difference was seen in early loading and one-stage loading with P-values of 0.06 and 0.09, respectively. However, in two-stage placement, significantly higher values were seen for oxidized surfaces (2.4 ± 0.8 mm) compared to turned surfaces (1.9 ± 0.8 mm), with P = 0.0004. Conclusions This study concludes that nonsignificantly higher survival rates are associated with oxidized surfaces compared to turned surfaces after two years of follow-up. Higher marginal bone levels were seen in oxidized surfaces for single implants and implants placed in two stages.

Impact of Implant Diameter on the Early Survival Rate of Dental Implants in the Saudi Population: A One-Year Retrospective Study

Introduction The use of dental implants provides a revolutionary solution to the problem of missing teeth in the oral cavity. The aim of this study was to assess the early implant survival rate in relation to implant diameter and site of placement. Methods The data were collected from 186 patients treated between January 2019 and June 2021. All the implants were evaluated and restored after three months of implant placement. The early implant survival was calculated for different implant diameters with the odds ratio (OR). Results A total of 373 implants were placed. Implants were placed in the following areas: upper posterior area (UPA), n = 123, upper anterior area (UAA), n = 49, lower posterior area (LPA), n = 184, and lower anterior area (LAA), n = 17. Implants of the following diameters were placed: 3.5 mm (n = 129), 4.3 mm (n = 166), and 5 mm (n = 78). The overall early survival rate was 97.32% after three months of placement. The highest early survival rate was at LAA (100%) and the lowest early survival rate was at UAA (95.9%). The implants 5 mm in diameter had the highest early survival rate (98.72%), while the implants 3.5 mm in diameter had the lowest early survival rate (94.57%). The ORs of the early implant survival were 4.7 [95% confidence interval (CI): 0.96-23.05)] and 4.42 (95% CI: 0.53-36.61) for the 4.3 mm and 5 mm implants, respectively, with no statistical significance. Conclusions The implants placed in the oral cavity had acceptable survival rates regardless of implant diameter or site of placement.

Comparative Evaluation of the Crestal Bone Level Around Pre- and Post-loaded Immediate Endoosseous Implants Using Cone-Beam Computed Tomography: A Clinico-Radiographic Study

Introduction  Dental implants replace missing teeth. Dental implants are surgically placed tooth root replacements that secure prosthetic teeth and bridges. Branemark's original dental implant technique included a mesiobuccal flap and a two-stage approach, needing 6-8 months of recovery following extraction, sterile conditions, machined titanium implants, 3-6 months without stress for osseointegration, and a detachable temporary prosthesis. The restoration would usually be ready a year following the implant surgery. Implant treatment seeks the best function, aesthetics, and complication risk. Implant therapy with low patient morbidity and fast extraction-to-restoration times is a secondary target. Instantaneous implant insertion has made implant dentistry more convenient for patients and clinicians. This study measures bone height before, after, and one month after implant placement using cone-beam computed tomography (CBCT). Materials and Methods Participants were selected from oral evaluation candidates. This investigation included 11 people missing front maxillary or mandibular teeth or root components. Diagnostic castings determined the interarch connection before surgery. Alginate maxillary and mandibular arch imprints were cast in Type III dental stone for diagnosis. CBCT scans were taken pre-operatively, post-implant, and post-prosthesis. After the tooth was removed, the empty socket was cleaned up with curettes. An intraoral periapical radiograph and manual probing were done to determine the implant's size. The implant was removed for examination after three months, and healing abutments and gingival formers were placed. Finally, fins were placed. The CBCT images also captured the bone height around the implants. The soft tissue parameters were recorded and evaluated at baseline and one-month following prosthetic loading as plaque index (PI). Radiographic evaluation was done at baseline and one-month following functional loading using CBCT. After one month following functional loading, crestal bone levels were measured again with the help of CBCT using Image J software (National Institutes of Health, Bethesda, Maryland, US). Results The sample population had an average age of 42.81 years, with a standard deviation of 13.44 years. Using a paired t-test, we found that the mean PI dropped significantly from pre-loading levels to one-month post-loading levels, with a p-value of less than 0.001. The mean crestal bone level (mesial) evaluated by CBCT at baseline and one-month post-loading was 2.52 ± 1.97 mm and 1.17 ± 1.31 mm, respectively. The mean difference between mean crestal bone loss (distal) at baseline and one-month post-loading was 0.94 ± 1.89 mm, which was not statistically significant. The mean difference between mean crestal bone loss (buccal) at baseline and one-month post-loading was 1.82 ± 1.60 mm, which was statistically significant. The mean difference between mean crestal bone loss (lingual) at baseline and one-month post-loading was 1.91 ± 1.53 which was statistically significant. Conclusion CBCT provides all the diagnostic data needed for implant placement; hence, it is recommended.

Effect of photofunctionalization on titanium bone-implant integration in ovariectomized rats

Osteoporosis is considered a risk factor for osseointegration during implant treatment. Photofunctionalization of titanium has been shown to improve bone-based cell adhesion, proliferation, and functional expression, increasing the bone-implant contact rate and bone-implant integration strength. This study aimed to test the hypothesis that photofunctionalization is effective for implant fixation using an osteoporosis rat model. In the biomechanical push-in test, the bone-implant integration strength of the photofunctionalization treatment group was 1.53 times that of the control group (p<0.05). These values implied that photofunctionalization restored the ovariectomy-induced low bone-implant integration strength to normal states. In the micro-CT analysis, the BV/TV of the photofunctionalization treatment group was 1.32 times that of the control group (p<0.05). These values implied that photofunctionalization restored the ovariectomy-induced low peri-implant bone formation to normal states. These results indicate that photofunctionalization treatment increased peri-implant bone formation and bone-implant integration strength in ovariectomized rats.

Osteoimmune regulation underlies oral implant osseointegration and its perturbation

In the field of biomaterials, an endosseous implant is now recognized as an osteoimmunomodulatory but not bioinert biomaterial. Scientific advances in bone cell biology and in immunology have revealed a close relationship between the bone and immune systems resulting in a field of science called osteoimmunology. These discoveries have allowed for a novel interpretation of osseointegration as representing an osteoimmune reaction rather than a classic bone healing response, in which the activation state of macrophages ((M1-M2 polarization) appears to play a critical role. Through this viewpoint, the immune system is responsible for isolating the implant biomaterial foreign body by forming bone around the oral implant effectively shielding off the implant from the host bone system, i.e. osseointegration becomes a continuous and dynamic host defense reaction. At the same time, this has led to the proposal of a new model of osseointegration, the foreign body equilibrium (FBE). In addition, as an oral wound, the soft tissues are involved with all their innate immune characteristics. When implant integration is viewed as an osteoimmune reaction, this has implications for how marginal bone is regulated. For example, while bacteria are constitutive components of the soft tissue sulcus, if the inflammatory front and immune reaction is at some distance from the marginal bone, an equilibrium is established. If however, this inflammation approaches the marginal bone, an immune osteoclastic reaction occurs and marginal bone is removed. A number of clinical scenarios can be envisioned whereby the osteoimmune equilibrium is disturbed and marginal bone loss occurs, such as complications of aseptic nature and the synergistic activation of pro-inflammatory pathways (implant/wear debris, DAMPs, and PAMPs). Understanding that an implant is a foreign body and that the host reacts osteoimmunologically to shield off the implant allows for a distinction to be drawn between osteoimmunological conditions and peri-implant bone loss. This review will examine dental implant placement as an osteoimmune reaction and its implications for marginal bone loss.

Assessment of Current Knowledge, Awareness and Attitude Towards Dental Implants as a Treatment Option for Replacement of Missing Teeth in Riyadh, Saudi Arabia

OBJECTIVE

To assess the current level of knowledge, awareness, and attitude towards dental implants as a treatment option for the replacement of missing teeth in Riyadh, Saudi Arabia.

MATERIAL AND METHOD

A random sample of 1000 Saudis (including both males and females) from Riyadh, Saudi Arabia, was selected. In accordance with research ethics codes, informed consent was obtained from research participants before approaching them via a structured online questionnaire using Google Forms; additionally, questionnaires were distributed in public places and promoted on social media to be answered anonymously. The data were coded, tabulated, and analyzed using Statistical Package for Social Sciences (SPSS; IBM Corp., Armonk, NY, USA) software. Descriptive statistics were calculated.

RESULTS

Around more than half of the study population (56.3%) opted for dental implants as a treatment option if they had to choose among the various options, and for those who did not choose dental implants, high cost was the major factor. The Pearson correlation between dental implant information and whether it was provided by their dentists and age was significant, and the majority of those who heard about dental implants are between the ages of 30 and 50. Also, it was noted that many of the participants who were working in the government sector (49.5%) had dental implants and were aware that dental implants as a treatment option were provided by their dentist when compared to those who were working in the private sector (12.1%) and the unemployed (24.7%), and this difference was statistically significant.

CONCLUSION

It was also observed that there is inadequate knowledge regarding the longevity of dental implants, and participants who were working in the government sector had dental implants and were aware that dental implants as a treatment option were provided by their dentist when compared to those who were working in the private sector, and around half are not aware that dental implant treatment can be covered by insurance.

The burden of diabetes on the soft tissue seal surrounding the dental implants

Soft tissue seal around implant prostheses is considered the primary barrier against adverse external stimuli and is a critical factor in maintaining dental implants' stability. Soft tissue seal is formed mainly by the adhesion of epithelial tissue and fibrous connective tissue to the transmembrane portion of the implant. Type 2 diabetes mellitus (T2DM) is one of the risk factors for peri-implant inflammation, and peri-implant disease may be triggered by dysfunction of the soft tissue barrier around dental implants. This is increasingly considered a promising target for disease treatment and management. However, many studies have demonstrated that pathogenic bacterial infestation, gingival immune inflammation, overactive matrix metalloproteinases (MMPs), impaired wound healing processes and excessive oxidative stress may trigger poor peri-implant soft tissue sealing, which may be more severe in the T2DM state. This article reviews the structure of peri-implant soft tissue seal, peri-implant disease and treatment, and moderating mechanisms of impaired soft tissue seal around implants due to T2DM to inform the development of treatment strategies for dental implants in patients with dental defects.

Awareness of Fixed Partial Dentures and Implant Rehabilitation of Missing Teeth Among a Subset of Saudi Population

Background  Maintaining one's sense of self requires having healthy teeth. A person's physical well-being is greatly impacted by their dental health. They are intimately related, and the socioeconomic situation of the individual largely determines how teeth are maintained. As a result, tooth loss causes injury to the stomatognathic system as well as the masticatory function. Morale is negatively impacted by psychological discomfort as well as the reduction in general quality of life brought on by tooth loss. Objectives  The purpose of this study was to assess the awareness of patients about various dental prosthetic rehabilitative procedures in Saudi Arabia, their preference(s) regarding the choice of treatment, and the motivating factors that drive them to avail of dental prosthetic rehabilitative treatment. Methods  After randomly selecting 600 individuals for the purpose of our investigation, a nine-variable questionnaire was framed by investigators to record the responses of those who consented to participate in our study. Results  Only 68.3% of the respondents were found to be aware of the several prosthodontic replacement choices. As mentioned by the majority of the respondents, the cost element was the biggest drawback for replacement. The benefits of choosing fixed partial dentures (FPD) or dental implants were judged to be aesthetics (41.1%) and the feel of one's own teeth (40.1%). Conclusion Only 68.3% of respondents reported knowing about the several prosthodontic replacement choices. The cost aspect was cited by 348 respondents as the biggest drawback to replacement. The perceived benefits of choosing FPD or dental implants were deemed to be aesthetics (41.1%) and the feel of one's own teeth (40.1%). We believe that patients' health and quality of life can be improved by raising awareness about and changing patients' attitudes toward the most cutting-edge treatment options that are readily available. This can be done by educating people about the drawbacks of delaying the replacement of missing teeth and other treatment options.

Radiographic density changes may be associated with overloading and implant loss on short implants: A 5-year analysis of a randomized controlled clinical trial

OBJECTIVES

To analyze changes in radiographic bone density around short implants with and without cantilevers at 5 years post-loading.

MATERIALS AND METHODS

Thirty-six patients with two adjacent posterior missing teeth participated in this randomized controlled clinical trial. All patients were randomly allocated to receive either two short implants (6 mm) with single-unit restorations (group TWO) or one single short implant (6 mm) with a cantilever restoration (group ONE-C). Patients were followed up at 6 months, 1, 3, and 5 years. Radiographic analysis was performed, through an arbitrary gray scale value (GSV) of the peri-implant bone, assessing the changes in radiographic density between groups and between time points. Differences in GSV between groups and over time were calculated using a generalized estimating equation to allow for adjustments for the correlation within individuals and between time points.

RESULTS

At 5 years, 26 patients remained in the study (15 in group ONE-C; 11 in group TWO). Implant survival rates were 80.4% in group TWO and 84.2% in group ONE-C (p = 0.894). The radiographic analysis revealed that GSVs increased in both groups over time (p < 0.001). The overall radiographic density was higher in group ONE-C than in group TWO in the maxilla (p = 0.030). Conversely, in the mandible, these significant differences between the groups were not found (p > 0.05). Compared to the implants that survived, the implants that failed demonstrated a distinct radiographic density pattern (p < 0.05).

CONCLUSION

Within the limitations of the present study, the radiographic bone density in the maxilla appears to increase distinctly around short implants when cantilevers are used. In contrast, the radiographic density in the mandible appears to be unaffected by the use of a cantilever, suggesting a lower threshold of adaptation to occlusal forces and thus a higher susceptibility to overload and implant loss at earlier time points.

In-office Bone-Anchored Hearing Implants via Minimally Invasive Punch Technique in a Veteran Population

OBJECTIVE

Describe the feasibility and safety of completing bone-anchored hearing implants via the minimally invasive punch technique in the in-office setting.

STUDY DESIGN

This single-institution case series included 20 patients who underwent in-office bone-anchored hearing implant placement under local anesthesia from 2018 to 2021.

SETTING

Veterans Affairs Northern California Healthcare System.

METHODS

Following completion of the case series, patients were retrospectively surveyed regarding their satisfaction with this approach via a modified SSQ-8 (Surgical Satisfaction Questionnaire) to fit our purposes.

RESULTS

A total of 23 implants were completed in the in-office setting on 20 patients. Intra- and postoperative complication rates, including skin changes, irritation, infection, and poor wound healing, were similar to or better than currently published complication rates in the literature. In addition, patients reported overwhelmingly positive responses on the SSQ-8, almost universally stating that they were "very satisfied" with their clinic experience.

CONCLUSION

This case series suggests that it is feasible and safe to complete this procedure in the clinic under local anesthesia, but further prospective studies are needed to evaluate this in a more generalized population.