Chitosan coatings on titanium-based implants - From development to characterization and behavior: A systematic review.

Chitosan is a promising natural polymer for coatings, it combines intrinsic antibacterial and pro-osteoblastic properties, but the literature still has a gap from the development to behavior of these coatings, so this systematic review aimed to answer, "What is the relationship between the physical and chemical properties of polymeric chitosan coatings on titanium implants on antibacterial activity and osteoblast viability?". PRISMA guidelines was followed, the search was applied into 4 databases and grey literature, without the restriction of time and language. The selection process occurred in 2 blinded steps by the authors. The criteria of eligibility were in vitro studies that evaluated the physical, chemical, microbiological, and biological properties of chitosan coatings on titanium surfaces. The risk of bias was analyzed by the specific tool. Of 734 potential articles 10 were included; all had low risk of bias. The coating was assessed according to the technique of fabrication, FT-IR, thickness, adhesion, roughness, wettability, antibacterial activity, and osteoblast viability. The analyzed coatings showed efficacy on antibacterial activity and cytocompatibility dependent on the class of material incorporated. Thus, this review motivates the development of time-dependent studies to optimize manufacturing and allow for an increase in patents and availability on the market.

Crafting Confidence: A Comprehensive Case Study of Full-Mouth Reconstruction Utilizing Implant-Supported Computer-Aided Design/Computer-Aided Manufacturing (CAD/CAM) Zirconia Restorations.

A 67-year-old male patient reported to the department with a chief complaint of tooth mobility. The patient presented with a medical history of diabetes for which he was on medication, and he also reported a history of chronic periodontitis. After a thorough assessment of the patient, a proper treatment plan was designed, which included full-mouth rehabilitation, prior to which the patient was advised full-mouth extraction. Six implants were inserted into the mandibular and maxillary arches as part of the treatment. After the implant was placed, zirconia was the preferred choice for the restoration because of its superior aesthetic results. Polyvinyl siloxane impression material was used to make implant impressions after an eight-week healing period. The case report provides the technique for the current approach to full-mouth rehabilitation with all six concepts of implant placement. In these situations, it is crucial to plan and insert implants correctly and adhere to the entire treatment plan. Restorations were performed using the latest computer-aided design/computer-aided manufacturing (CAD/CAM) technologies for a more aesthetically pleasing result. The case study highlights the significance of meticulous preparation and implementation for the accomplishment of successful full-mouth rehabilitation.

Immediate Implant Placement in Conjunction with Maxillary Sinus Lifting and Grafting.

Bone deficiency in the posterior maxillary bone can be associated with a large sinus cavity and this dilemma can limit implant placement for dental rehabilitation in this area. The maxillary sinus lifting technique can be the solution for many clinical situations with minimal bone height, allowing the placement of longer implants. Autogenous bone graft is a safe and reliable material for reconstructive surgery. In this article, a case of an elderly male patient with inadequate maxillary bone height is presented. Simultaneous maxillary sinus elevation and implant placement with autogenous parietal bone graft were performed.

Smart Delivery of Biomolecules Interfering with Peri-Implant Repair in Osteoporotic Rats.

Bisphosphonates are widely used for the treatment of postmenopausal osteoporosis; however, they cause several long-term side effects, necessitating the investigation of local ways to improve osseointegration in compromised bone tissue. The purpose of this study was to evaluate peri-implant bone repair using implants functionalized with zoledronic acid alone (OVX ZOL group, n = 11), zoledronic acid + teriparatide (OVX ZOL + TERI group, n = 11), and zoledronic acid + ruterpy (OVX ZOL + TERPY group, n = 11) compared to the control group (OVX CONV, n = 11). Analyses included computer-assisted microtomography, qualitative histologic analysis, and real-time PCR analysis. Histologically, all functionalized surfaces improved peri-implant repair, with the OVX ZOL + TERI group standing out. Similar results were found in computerized microtomography analysis. In real-time PCR analysis, however, the OVX ZOL and OVX ZOL + TERPY groups showed better results for bone formation, with the OVX ZOL + TERPY group standing out, while there were no statistical differences between the OVX CONV and OVX ZOL + TERI groups for the genes studied at 28 postoperative days. Nevertheless, all functionalized groups showed a reduced rate of bone resorption. In short, all surface functionalization groups outperformed the control group, with overall better results for the OVX ZOL + TERI group.

Effectiveness of using implant fixture as a ridge expander.

OBJECTIVES: Adequate bone thickness around dental implants is vital for their stability and to reduce resorption. This study evaluated the ability of implant fixtures to serve as ridge expanders by measuring width changes pre- and post-implantation. MATERIALS AND METHODS: Measurements including initial alveolar bone width, post-osteotomy width, post-expansion width, and buccal bone thickness were recorded for patients undergoing implant placement. Bone quality was assessed using established criteria. RESULTS: Of the 102 subjects (52% male, 48% female), significant ridge width increases at 0 mm and 2 mm levels were noted (p < 0.05). Larger implant diameters resulted in greater ridge expansion. Absence of prior augmentation was linked to higher bone quality (B = -1.684, p = 0.001), explaining 15% of bone quality variance. Ridge expansion effects also correlated with the site, implant diameter, and design. CONCLUSIONS: Dental implant fixtures can effectively expand the ridge, with expansion influenced by implant diameter, anatomical location, prior augmentation, and implant design. These factors must be considered for tailored treatment planning in implant dentistry. CLINICAL RELEVANCE: This study's clinical relevance lies in its exploration of the potential benefits of dental implant fixtures can effectively to expand the ridge taking into consideration implant diameter, anatomical location, prior augmentation, and implant design.

Bone Regeneration in The Anterior Maxilla with Titanium Mesh and Advanced-Platelet-Rich Fibrin: a Two-Year Follow-up Case Report.

Guided bone regeneration involving the use of titanium mesh and platelet-rich fibrin could be a feasible approach in cases of severely atrophic ridges. The purpose of this case report was to present an esthetic and functional rehabilitation in the anterior maxilla with the installation of dental implants in conjunction with guided bone regeneration using titanium mesh and advanced platelet-rich fibrin (A-PRF). A 60-year-old patient presented bone atrophy and partial edentulism in the anterior maxilla. After clinical and cone beam computed tomography assessment, guided bone regeneration was planned using a titanium mesh and A-PRF with xenograft bone. After eight months of healing, the dental implants were placed with the aid of a surgical guide to obtain accurate three-dimensional positioning. Prosthetic rehabilitation was carried out with individualized crowns. After two years of follow-up, radiographic analysis demonstrated a good quality and density of the bone tissue adjacent to the dental implants. No radiolucent areas were observed, and there were no clinical signs of failure. In cases of severe atrophy, using a titanium mesh and A-PRF proved to be a feasible alternative for bone reconstruction prior to dental implant placement. This approach can aid dental professionals in achieving an ideal implant positioning for rehabilitation with individualized crowns.

Outcome Difference between Short and Longer Dental Implants Placed Simultaneously with Alveolar Bone Augmentation: a Systematic Review and Meta-Analysis.

Objectives: This systematic review and meta-analysis aim to provide detailed insights into the clinical performance of short and longer dental implants placed simultaneously with bone augmentation. Material and Methods: The search for literature was performed across MEDLINE (PubMed), ScienceDirect and the Cochrane Library databases, adhering to specific selection criteria and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Only articles published in English between 2014 and 2024 were considered for data collection. Primary outcomes were survival rate (SR), marginal bone loss (MBL) and complications. Clinical outcomes were as follows: bleeding on probing (BOP), periodontal pocket depth (PPD), and implant stability quotient (ISQ). Quality and risk of bias assessment were evaluated by the Critical Appraisal Checklist tool for randomized controlled trials developed by the Joanna Briggs Institute. Results: A total of 14678 articles were screened, with 9 meeting the inclusion criteria and being utilized for this systematic review and meta-analysis. A total of 495 patients with 984 implants (491 short and 493 longer implants) showing a SR of 93.91% for the short implants and 91.83% for the longer implants. Meta-analysis revealed statistically significant difference between short implants and longer implants simultaneously placed with alveolar bone augmentation in relation to MBL (-0.513 mm, 95% CI = -0.93 to -0.096; P = 0.02), and in PPD (-0.247, 95% CI = -0.515 to 0.022; P = 0.07). Conclusions: When comparing the results of treatment with short and longer dental implants combined with alveolar bone augmentation, short implants showed better clinical results regarding the parameters of survival rate, marginal bone loss and complications.

The Use of Platelet-Rich Fibrin in Sinus Floor Augmentation Surgery: a Systematic Review.

Objectives: This systematic review aims to critically assess the impact of platelet-rich fibrin on maxillary sinus floor augmentation and outline the specific aspects of new bone formation, bone height, implant stability quotient, and Schneiderian membrane thickness. Material and Methods: A systematic review and meta-analysis were conducted, analysing studies from MEDLINE (PubMed), the Cochrane Library, and ScienceDirect databases, published from January 29, 2018 until January 29, 2024 that compared maxillary sinus floor augmentation (MSFA) using bone graft material with and without platelet-rich fibrin (PRF). This review focused on patients 18 years and older who undergone MSFA before the dental implant placement. It systematically examined five studies, encompassing randomized controlled trials, and reported on 112 MSFA procedures conducted in 84 patients. Results: The meta-analysis reveals a marginal significance in new bone formation with PRF, suggesting a trend towards beneficial outcomes that were not statistically significant. No significant impact on bone height was observed. However, a notable improvement in implant stability quotient (ISQ) was recorded, indicating enhanced implant stability with PRF. The Schneiderian membrane thickness did not show significant changes post-treatment with PRF. Conclusions: While platelet-rich fibrin shows promise in enhancing implant stability, its effects on new bone formation and Schneiderian membrane thickness are inconclusive, highlighting the need for further research. Platelet-rich fibrin did not significantly affect bone height. The findings support platelet-rich fibrin's potential as a beneficial adjunct in maxillary sinus floor augmentation, particularly for implant stability.

Zirconia full-arch implant prostheses: Survival, complications, and prosthetic space dimensions with 115 edentulous jaws.

PURPOSE: To assess the survival and complication rates of 115 monolithic zirconia implant-supported fixed complete dental prostheses (IFCDPs) with an up to 6-year follow-up. MATERIALS AND METHODS: One hundred fifteen edentulous jaws (71 patients) underwent complete-arch implant treatment with a digital workflow and were rehabilitated with monolithic zirconia IFCDPs. The primary outcome was to assess survival and complication rates while the secondary outcome was to measure the cross-sectional dimensions (prosthetic space) of those 115 monolithic zirconia IFCDPs and to correlate potential technical complications with the prosthetic space dimensions. RESULTS: Out of the 115 zirconia IFCDPs, 2 fractured, yielding a 98.6% survival rate up to a 6-year follow-up. The most commom minor technical complications were loss of screw access channel filling and porcelain chipping for the modified monolithic IFCDPs. There was no significant association between the count and type of complications and jaw location (maxilla vs. mandible) or prosthesis type (FP1 vs. FP3), according to Fisher's exact test. For maxillary zirconia IFCDPs, the mean square surface for the at the posterior abutment cross-sectional area was 25.18 mm2 at the lingual side of the abutment and 34.19 mm2 at the buccal side, respectively. The anterior abutment cross-sectional area was 33.92 mm2 at the lingual side of the abutment and 29.49 mm2 at the buccal side, respectively. For mandibular zirconia IFCDPs, the mean square surface at the posterior abutment cross-sectional area was 29.89 mm2 at the lingual side of the abutment and 39.05 mm2 at the buccal side, respectively. The anterior abutment cross-sectional area was 27.07 mm2 at the lingual side of the abutment and 56.50 mm2 at the buccal side, respectively. At the connector cross-sectional area, the mean square surface for the maxillary zirconia IFCDPs was 64.33 and 90.56 mm2 for the mandibular zirconia IFCDPs. The two fractures occurred in the midline (anterior area) for both maxillary FP1 prosthesis and mandibular FP3 prosthesis. The mean surface area at the connector for the maxillary FP1 prosthesis was 28.50 and 82.11 mm2 for the mandibular FP3 prosthesis, and was within the range of IFCDP connector square surface area. There was no significant association between the thickness of the zirconia prosthesis and the encountered prosthesis fractures. CONCLUSIONS: Monolithic zirconia IFCDPs yielded a 98.6% survival rate, after a mean observation period of 62 months with an SE of 3.1. The connector mean surface area in the two fractured IFCDPs was within the square surface range (minimum-maximum) as for the remaining 113 complication-free IFCDPs.

Comparison of implant placement at crestal and subcrestal levels in aesthetic zone: A finite element analysis.

PURPOSE: The success rate of the implant treatment, including aesthetics and long-term survival, relies heavily on preserving crestal peri-implant bone, as it determines the stability and long-term outcomes. This study aimed to demonstrate the stress differences in the crestal bone resulting from dental implant placement at various depths relative to the crestal bone level using finite element analysis. MATERIALS AND METHODS: Three study models were prepared for implant placement at the crestal bone level (CL), 1 mm depth (SL-1), and 2 mm depth (SL-2). Implants were placed in the maxillary central incisor region of each model, and 100 N vertical and oblique forces were applied. The von Mises, maximum principal (tensile), and minimum principal (compressive) stresses were evaluated. RESULTS: The CL model exhibited the highest stresses on the implant, abutment, and abutment screws under vertical and oblique forces. For maximum principal stress in the crestal bone under vertical force, the SL-2, SL-1, and CL models recorded values of 6.56, 6.26, and 5.77 MPa, respectively. Under oblique forces, stress values for SL-1, SL-2, and CL were 25.3, 24.91, and 23.76 MPa, respectively. The CL model consistently exhibited the lowest crestal bone stress at all loads and the highest stress values on the implant and its components. Moreover, considering the yield strengths of the materials, no mechanical or physiological complications were noted. CONCLUSIONS: Placing the implant at the crestal level or subcrestally beyond the cortical layer could potentially reduce stress and minimize crestal bone loss. However, further studies are warranted for confirmation.

Immediate single-tooth implant placement in bony defect sites: A 10-year randomized controlled trial.

BACKGROUND: It is unclear whether an intact buccal bony plate is a prerequisite for immediate implant placement in postextraction sockets. The aim of this 10-year randomized controlled trial was to compare peri-implant soft and hard tissue parameters, esthetic ratings of, and patient-reported satisfaction with immediate implant placement in postextraction sockets with buccal bony defects ≥5 mm in the esthetic zone versus delayed implant placement after alveolar ridge preservation. METHODS: Patients presenting a failing tooth in the esthetic region and a buccal bony defect ≥5 mm after an extraction were randomly assigned to immediate (Immediate Group, n = 20) or delayed (Delayed Group, n = 20) implant placement. The second-stage surgery and provisional restoration placement occurred 3 months after implant placement in both groups, followed by definitive restorations 3 months thereafter. During a 10-year follow-up period, marginal bone levels (primary outcome), buccal bone thickness, soft tissue parameters, esthetics, and patient-reported satisfaction were recorded. RESULTS: The mean marginal bone level change was -0.71 ± 0.59 mm and -0.36 ± 0.39 mm in the Immediate Group and the Delayed Group after 10 years (p = 0.063), respectively. The secondary outcomes were not significantly different between both groups. CONCLUSIONS: Marginal bone level changes, buccal bone thickness, clinical outcomes, esthetics, and patients' satisfaction following immediate implant placement, in combination with bone augmentation in postextraction sockets with buccal bony defects ≥5 mm, were not statistically different to those following delayed implant placement after ridge preservation in the esthetic zone. PLAIN LANGUAGE SUMMARY: Immediate implant placement in case of a failing tooth is a favorable treatment option for patients because it considerably shortens treatment time and the number of surgical treatments. The question is if an intact buccal bone wall is necessary for immediate implant placement. A 10-year study was performed in which 20 patients with a failing tooth in the frontal region of the upper jaw were treated with immediate implant placement and were compared with 20 patients in whom a more conventional treatment strategy was followed in which the failing tooth was first removed and the bone gap restored and the implant placed in a second step. After a 10-year follow-up period, it appeared that the bone around the implant was very stable, gums were healthy, and patients were very satisfied with the result. There was no difference between the two treatment procedures. Such results mean that professionals can discuss the procedure with the patient and apply the individual's preference.

Osseointegrative and antimicrobial properties of graphene oxide nano coated dental implants: A systematic review.

Introduction: Osseointegration stands as a pivotal concept within the realm of dental implants, signifying the intricate process through which a dental implant integrates with the adjoining bone tissue. Graphene oxide (GO) has been shown to promote osseointegration, the process by which the implant fuses with the surrounding bone. The objective of this study was to assess the osseointegrative and antimicrobial properties of GO nano coated dental implants. Methods: A systematic search was conducted using electronic databases (e.g., PubMed, Scopus, Web of Science) to identify relevant studies published. Inclusion criteria encompassed studies that evaluated the effects of GO nano coating on osseointegrative and antimicrobial characteristics of dental implants. Studies not written in English and published before 2012 were excluded. Results: The initial search yielded a total of 127 potential studies, of which six met the inclusion criteria and five were included in the review. These studies provided data on GO nano coated dental implants and their osseointegrative and antimicrobial properties. All the included studies showed moderate risk of bias. None of the studies provided information related to sample size calculation or sampling technique. Discussion: The findings from the included studies demonstrated that GO nano coating had a positive impact on osseointegrative properties of dental implants. Enhanced bone-implant contact and increased bone density were observed in animals and humans receiving GO nano coated implants. Furthermore, the antimicrobial properties of GO nano coating were found to inhibit bacterial colonization and biofilm formation on the implant surface, reducing the risk of implant-associated infections. Conclusion: The findings indicate that GO nano coating holds promise in enhancing the success rate and longevity of dental implants. However, more studies with larger sample sizes, are needed to further strengthen the evidence and determine the long-term effects of GO nano coated dental implants.

A new guide for enhancing dental implant placement: an in vitro assessment of accuracy.

This study aimed to design a new surgical guide for controlling the mesiodistal distance between implant osteotomies and adjacent teeth as well as the osteotomy depth in partially edentulous patients. The guide kit was designed with design software and milled with a CNC (computer numerical control) router. The guide consisted of 2 components-stoppers and crown guides-for determining the drilling depth and mesiodistal position, respectively. The stoppers were designed in 7.5-, 9.5-, and 11.5-mm lengths, and the crown guides were fabricated with outer diameters of 5.0, 6.0, 7.0, and 8.0 mm. The accuracy of the guide was assessed by preparing a total of 20 implant osteotomies in 4 partially edentulous models and comparing the dimensions of the actual osteotomies to the values that were predicted to occur with the use of the surgical guides. Osteotomies were prepared using the 7.5-mm stopper with either the 7.0- or 8.0-mm crown guide. Cone beam computed tomography (CBCT) was used to obtain images for analysis of osteotomy-tooth mesiodistal distances, which were predicted to be 3.0 or 5.5 mm, depending on position; interosteotomy mesiodistal distances, which were predicted to be 3.0 mm; and osteotomy depth, which was predicted to be 11.5 mm. A 1-sample t test was used to determine if there were significant differences between the predicted values and the measurements of the guided osteotomies on the CBCT images of the mandibular models, and an independent t test was conducted to compare the results of 3.0- and 5.5-mm osteotomy-tooth distances (α = 0.05). Differences between the predicted and actual values of the interosteotomy mesiodistal distance (P = 0.516) and osteotomy depth (P = 0.847) were not statistically significant. The actual osteotomy-tooth mesiodistal distances were significantly different from the predicted values of 3.0 (P = 0.000) and 5.5 mm (P = 0.001), with higher mean differences of 0.46 and 0.60 mm, respectively. The designed guide had a high accuracy in achieving optimal linear interosteotomy mesiodistal distances and osteotomy depths, and the obtained mean values were clinically acceptable.

Hybrid-resolution facial and dental scanning: a cost-effective approach to utilizing 3D facial data in anterior dental implant restoration.

As digital technology becomes more prevalent in the practice of dental medicine, methods to fully replace 2-dimensional photography and analog devices such as the facebow are still in their infancy. As more practices adopt 3-dimensional (3D) intraoral scanners, effective digital communication of the relationships between the teeth and the face becomes essential. With the high cost of intraoral scanners, the additional expense of a face scanner is not a feasible investment for many practices. This article explores a technique for meshing (lower resolution) facial data obtained from a smartphone-based scanner with high-resolution intraoral scan data. In this approach, the data from a free 3D scanning application on a smartphone and a traditional intraoral scanner are meshed so that high-resolution data are available for intraoral features and lower resolution data are used to capture the gross contours of the face. In this way, a hybrid-resolution composite scan that incorporates all of the data needed to simulate the face and accurately reproduce the teeth is generated without the cost of additional scanning equipment. This article defines a new term, the facial registration scan, for use alongside the familiar digital bite registration obtained with an intraoral scanner. To illustrate the clinical use of the hybrid-resolution scan concept, this article presents a case in which this method was used for the restoration of maxillary anterior implants.

Horizontal ridge augmentation through ridge expansion via osseodensification, guided bone regeneration and ridge­split: Systematic review and meta­analysis of clinical trials.

The aim of the present systematic review was to compare three ridge augmentation procedures in order to assist clinicians in finding the ideal surgical method relative to the horizontal bone gain needed and the width of the alveolar ridge available. An electronic and hand literature search was performed in the online databases PubMed-Medline, Cochrane Central Register of Controlled Trials, EMBASE, Cochrane Oral Health Group Trials Register and Web of Science, and various specialized journals, between January 2017 and December 2022. The included studies were evaluated using the Methodological Index for Non-randomized Studies score and Cochrane's RoB tool. The primary variable studied in the meta-analysis was the final bone gain. The implant survival rate and initial ridge width were the secondary variables. Then four studies on ridge expansion via osseodensification (OD), seven on guided bone regeneration (GBR) and seven on the ridge-split technique (RS) were included in the review; 17 out of 18 were selected for meta-analysis. The mean horizontal bone gain for OD was 2.151 mm [1.327-2.975 mm; 95% confidence interval (CI)], for GBR was 4.036 mm (3.351-4.772 mm 95%CI) and for RS was 3.661 mm (2.991-4.399 mm 95%CI). The results were statistically significant (P=0.002). GBR reported the most bone gain horizontally, followed closely by RS and then OD. OD is a recent technique that should be taken into account when discussing the protocols of horizontally atrophied ridge rehabilitation.

Four-mm-short implants in the rehabilitation of posterior atrophic jaws: A retrospective study on 212 patients with a mean follow-up of 8.02 years.

OBJECTIVE: This study aimed to assess clinical efficacy of 4-mm-short implants in patients with posterior severe vertical bone atrophy in the medium- and long-term follow-up. MATERIALS AND METHODS: Patients rehabilitated with 4-mm-short implants in the posterior atrophic jaws, with a minimum follow-up of 3 years post-loading, were included in the study. Data were collected for eligible patients, and marginal bone loss (MBL) for each implant was evaluated. The research outcomes were implant failure, MBL and complications. RESULTS: A total of 212 patients with 496 implants were included, resulting in a mean follow-up of 8.02 ± 2.17 years. The implant survival rate was 95.36% (95% CI: 93.12%-97.04%). More implant failures were observed in the maxilla (p = .02) and fewer failures were observed in patients undergoing more number of hygienic sessions per year (p < .001). The average MBL after 1-year-loading was 0.47 mm, increasing to 0.59 mm after 10 years; after 3 years no statistically significant increase in MBL was observed. Maxillary implants showed greater bone loss than mandibular ones (p < .001). More frequent professional oral hygiene sessions per year resulted being related with reduced MBL (p < .001). CONCLUSIONS: Four-mm-short implants showed high survival rates with an up to 10-year follow-up. Their use can offer a fixed prosthetic solution for patients with posterior vertical bone atrophy, minimizing surgical invasiveness, rehabilitative times and costs.

Inverted bone block for a mandibular lateral ridge augmentation: A case report.

The purpose of this report is to describe an original technique for bone grafting using an inverted autogenous bone block taken from the same edentulous site that was to be implanted. A 54-year-old female presented for replacement of a missing lower premolar. Clinical and radiographical assessments revealed a deficiency in the width of the alveolar ridge. It was decided to expand the edentate area using an inverted bone block. The graft was harvested from the same edentate site that was to be implanted. The crestal bone width after nine months of healing was increased, and an implant was placed. An autogenous inverted bone block can be used as a bone grafting procedure to augment some bone-deficient sites prior to dental implantations. This novel technique provides an autogenous bone without the complexity of having a second surgical site. This technique can be used in specific situations when there is proper bone anatomy.

Comparative analysis of dental implant placement accuracy: Semi-active robotic versus free-hand techniques: A randomized controlled clinical trial.

BACKGROUND: Robot-assisted implant surgery has emerged as a novel digital technology, and the accuracy need further assessment. PURPOSE: This study aimed to compare the accuracy of single dental implant placement between a novel semi-active robot-assisted implant surgery (RAIS) method and the conventional free-hand implant surgery (FHIS) method through a multicenter, randomized controlled clinical trial. MATERIALS AND METHODS: Patients requiring single dental implant placement were recruited and randomized into RAIS and FHIS group. Deviations at the platform, apex, and angle between the planned and final implant positions were assessed in both groups. Additionally, the evaluation of instrument and surgical complications was examined. RESULTS: A total of 140 patients (median age: 35.35 ± 12.55 years; 43 males, 97 females) with 140 implants from four different research centers were included, with 70 patients (70 implants) in the RAIS group and 70 patients (70 implants) in the FHIS group. In the RAIS and FHIS groups, the median platform deviations were 0.76 ± 0.36 mm and 1.48 ± 0.93 mm, respectively (p < 0.001); median apex deviations were 0.85 ± 0.48 mm and 2.14 ± 1.25 mm, respectively (p < 0.001); and median angular deviations were 2.05 ± 1.33° and 7.36 ± 4.67°, respectively (p < 0.001). Similar significant difference also presented between RAIS and FHIS group in platform vertical/horizontal deviation, apex vertical/horizontal deviation. Additionally, implants with self-tapping characteristics exhibited significantly larger deviations compared with those without self-tapping characteristics in the RAIS group. Both RAIS and FHIS methods demonstrated comparable morbidity and safety pre- and post-operation. CONCLUSIONS: The results indicated that the RAIS method demonstrated superior accuracy in single dental implant placement compared with the FHIS method. Specifically, RAIS exhibited significantly smaller deviations in platform, apex, and angular positions, as well as platform and apex vertical/horizontal deviations. This clinical trial was not registered prior to participant recruitment and randomization. https://www.chictr.org.cn/showproj.html?proj=195045.

Maxillary sinus membrane perforation rate utilizing osseodensification-mediated transcrestal sinus floor elevation: A multicenter clinical study.

PURPOSE: This multicenter cross-sectional clinical study aimed to evaluate the membrane perforation rate during transcrestal sinus floor elevation (TSFE) using osseodensification (OD) burs and assess risk factors associated with the procedure. MATERIALS AND METHODS: This study was conducted in six centers, following ethical standards and approved by local committees. It included patients over 18 years old missing maxillary posterior teeth with crestal residual bone height (RBH) ≥2 and ≤6 mm. Preoperative evaluations were done, including CBCT scans, to assess bone dimensions and sinus health. All centers and surgeons followed a standardized surgical protocol for TSFE using OD burs. Surgical complications, particularly sinus membrane perforations, were recorded and analyzed. Factors such as implant site, premolars or molars, as well as, healed or fresh socket, along with initial RBH were evaluated for their impact on membrane perforation rate. Descriptive statistics, χ2, and logistic regression analysis were used to analyze the data. RESULTS: A total of 621 subjects with an average age of 57.9 years were included. Sinus lifting was performed at 670 sites, with 621 implants placed in the maxilla. The majority of sinus lifts were done in the molar region (76.87%) and in healed bone sites (74.33%). The average RBH was 5.1 mm (ranging from 2 to 7 mm). Sinus membrane perforation occurred in 49 cases (7.31%). RBH ≤3 mm posed a risk factor for sinus membrane perforations followed by RBH >3 and ≤5 mm. Tooth region and implant site were not associated as risk factors for sinus membrane perforation. CONCLUSION: OD drilling used for TSFE resulted in low membrane perforation rate. Challenging scenarios of severe posterior maxillary atrophy presented as risk factors for increased perforation rate.

Soft-Tissue Phenotype as a Risk Indicator of Peri-Implantitis and Peri-Implant Soft-Tissue Dehiscence-A Cross-Sectional Study.

AIM: To investigate the association, as well as to characterize the associated panel of pro- and anti-inflammatory markers, between the different components of the peri-implant phenotype and the presence of peri-implantitis/peri-implant soft-tissue dehiscence (PISTD). MATERIALS AND METHODS: A total of 324 implants in 112 patients were included. The following components of the peri-implant phenotype were clinically measured through the use of a manual periodontal probe or a digital calliper: keratinized mucosa width (PIKM-W), mucosal thickness (MT), attached mucosa (AM) and vestibulum depth (VD). The presence of peri-implantitis and PISTD was assessed through clinical and radiographic examination. Mixed-models logistic regression analyses were performed to analyse the association between peri-implant phenotype and the presence of peri-implantitis or PISTD, adjusting for relevant confounders. Multiplex immunoassays were employed to evaluate the peri-implant crevicular fluid levels of a panel of pro- and anti-inflammatory markers. RESULTS: Peri-implant health, peri-implant mucositis and peri-implantitis were diagnosed in 36.6%, 21.4% and 42% of the patients (classified according to their worst implant) and 35.2%, 34.3%, and 30.5% of the implants, respectively. In the multi-level multiple regression model, the absence of PIKM-W (odds ratio [OR] = 9.24; 95% CI: 2.73-31.28), the absence of attached mucosa (OR = 19.58; 95% CI: 6.12-62.56) and a reduced (<4 mm) vestibulum depth (OR = 2.61; 95% CI: 1.05-6.48) were associated with peri-implantitis. Similarly, the absence of PIKM-W (OR = 6.32; 95% CI: 1.67-23.83), a thin (<2 mm) mucosa (OR = 157.75; 95% CI: 14.06-1769.9) and a reduced vestibulum depth (OR = 3.32; 95% CI: 1.02-10.84) were associated with the presence of PISTD. Implants with PIKM-W = 0 mm showed statistically significantly higher levels of interferon-γ in both regular (≥2 maintenance/year) and irregular (<2 maintenance/year) compliers (p = 0.046 and p = 0.012). In irregular compliers, the absence of PIKM-W was also associated with statistically significantly higher levels of interleukin (IL)-1ß and IL-21 (p = 0.016, p = 0.046). These associations were independent of the effect of relevant confounders (e.g., plaque, compliance with maintenance, etc.). CONCLUSIONS: Within their limits, the present findings indicate that (a) peri-implant soft-tissue phenotype appears to be associated with the presence of peri-implantitis and PISTD, and (b) in the absence of PIKM-W, the inflammatory response seems to be dysregulated and the soft-tissue remodelling up-regulated.