Atrophic Maxilla Research Articles

Clinical outcomes of bizygomatic with anterior implants for restoring atrophic maxilla and all-on-four implants for restoring mandible: A case report

Clinical outcomes of bizygomatic with anterior implants for restoring atrophic maxilla and all-on-four implants for restoring mandible: A case report

Bone Resorption Assessment Following Zygomatic Implants Surgery over 10 Years of Follow-Up

The presence of sufficient bone volumes is one of the most important criteria for the success of oral implant osseointegration. Therefore, the rehabilitation of edentulous atrophic maxillae represents the greatest challenge in terms of oral rehabilitation. Techniques such as bone grafts, angled implants, short implants, tuberosity, and pterygoid implants may not always be a viable alternative in the subsequent rehabilitation of the posterior atrophic maxilla. A breakthrough occurred when Brånemark first introduced longer, custom-designed implants inserted into the zygomatic bone to support craniofacial prosthesis in the 1980s. When used in the treatment of atrophic jaws, zygomatic implants provide a safe and effective alternative, with stable long-term results. Objectives: We aimed to retrospectively evaluate zygomatic bone resorption ten years after the placement of zygomatic implants. Methods: A retrospective observational study was designed to evaluate bone resorption over ten years following the placement of zygomatic implants. In a study group of 50 patients, using Hounsfield scales, the area of the zygoma and its bone density were established and evaluated. The NewTom NNT Analysis software (NewTom®, Imola, Italy) was employed to trace the bone and implant limits on CBCT scans. Using this software, the three-dimensional information of the postoperative CBCT image was compared with the ten-year postoperative CBCT image, allowing for the assessment of the zygomatic bone resorption and bone density. Results: Highly significant statistical differences to an alpha level of 0.01 were identified between T0 (pre-op), T1 (12 months), and T2 (120 months) concerning zygomatic bone density, both in the first and in the second quadrants. The post hoc Bonferroni test revealed that significant statistical differences were observed between T0 and the remaining timepoints (T1 and T2), with the latter two exhibiting similar values. Conclusions: The evaluation of the resorption at the level of the zygoma, ten years after the placement of zygomatic implants, reveals that there are no significant losses between the initial and final controls. Therefore, it follows that this type of implant rehabilitation represents a viable alternative approach in patients with bone atrophy of the maxilla, offering a predictable therapeutic solution that enables immediate full function and excellent long-term success rates. However, we must not neglect the potential for future innovations in GBR involving the use of barrier membranes, either resorbable or non-resorbable, and even the application of titanium alveolar customized osteogenic scaffold, in conjunction with autologous bone grafts or biomaterials.

Five-Year Comparative Study of Zygomatic and Subperiosteal Implants: Clinical Outcomes, Complications, and Treatment Strategies for Severe Maxillary Atrophy

Five-Year Comparative Study of Zygomatic and Subperiosteal Implants: Clinical Outcomes, Complications, and Treatment Strategies for Severe Maxillary Atrophy

Evaluation of prostheses retained zygomatic and dental implants in large defects in the maxilla due to tumors or major trauma by biomechanical 3- dimensional finite element analysis

BackgroundZygomatic implants are becoming an ideal treatment approach for implant-supported prosthesis treatment developed for the atrophic maxilla. This study aims to evaluate the amount and distribution of stress in implants and peri-implant bone using different implant-supported prosthesis configurations in Aramany Class I maxillary defects through 3-dimensional finite element analysis.MethodsA 3-dimensional finite element model of the Aramany class I defect was created. Three different implant-supported prostheses were modelled: model 1: 1 zygomatic implant and 3 dental implants, model 2: 1 zygomatic implant and 2 dental implants, and model 3: 2 zygomatic implants. Vertical and horizontal loads of 150 N were applied in 6 different ways to the defected and non-defective areas. Maximum principal stress and von mises stresses in the bone surrounding the implants were evaluated.ResultsWhen all loading conditions were evaluated with both porcelain layer on Co-Cr framework and acrylic layer on acrylic framework, the highest maximum principal stress value was observed in Model 3. In contrast, the lowest value was observed in Model 1. The highest maximum principal stress occurred when a horizontal load was applied simultaneously to both the defective and non-defective areas. In contrast, the lowest value was observed when a vertical load was applied to the non-defective area. The von Mises stress values were found to be similar across all models when both restoration materials were used.ConclusionsBased on the results of this study, it can be concluded that increasing the number of implants in the non-defective area reduces the highest stress value while using acrylic as a restoration material slightly increases the stress value.

Long-Term Effects of Sinus Floor Elevation with and Without Bone Graft: A Systematic Analysis of Randomized Clinical Trials.

Background and Objective: The aim of this systematic review was to assess clinical trials on the efficiency of sinus lift techniques with and without bone grafting in the atrophic posterior maxilla. Materials and Methods: This article was written under the PRISMA and the Cochrane Handbook for Systematic Reviews of Interventions guidelines. PubMed, Scopus, and Web of Science databases were electronically searched until December 2023. The risk of bias was assessed according to Cochrane Risk of Bias tool guidelines. Statistical analysis was performed for implant survival rate (ISR), marginal bone loss (MBL), and endo-sinus bone gain (ESBG). Results: At the end of the electronic search, 5 clinical trials were considered eligible. Statistical analysis was achieved for osteotome sinus floor elevation. The ISR at 3 years had a risk ratio (RR) of 0.98 [0.90, 1.07] (CI 95%), p = 0.7, and at 5 years, RR 1.02 [0.93, 1.11] (CI 95%), p = 0.68. The MBL, at 3 years, indicated a weighted mean difference (WMD) of 0.01 [-0.15, 0.16] (CI 95%), p = 0.93, and at 5 years, WMD of -0.08 [-0.53, 0.37] (CI 95%), p = 0.73. ESBG at 3 years had a WMD of -0.44 [-1.05, 0.17] (CI 95%), p = 0.16, and at 5 years, WMD of -0.61 [-1.63, 0.41] (CI 95%), p = 0.24. Conclusions: The available evidence underlines that the osteotome sinus floor elevation technique without bone graft may be used.

Pterygoid implants as alternative to bone augmentation in implant dentistry.

The ultimate dental implant challenge is reconstruction of the severely resorbed maxilla, especially in patients with long-term edentulism or multiple previous failed attempts at dental implant placement and full-arch implant rehabilitation. Before implant dentistry, complete dentures, which are limited by poor retention and lack of support that the alveolar ridge offers in atrophic maxillae, were the only option for these patients. Pterygoid implants are now a valid and valuable resource for the rehabilitation of the posterior atrophic maxilla. This chapter will cover pterygoid implant surgical and pre-surgical planning, surgical procedures and protocols, including multiple techniques commonly utilised to place and restore these implants comprehensively.

Comparative Clinical Outcomes of Two Different Zygomatic Implant Protocols for the Rehabilitation of Severely Atrophic Maxillae: A Retrospective Analysis.

This retrospective study aimed to compare extended sinus lift and extramaxilla surgical protocols for restoring severely atrophic maxillae with zygomatic implants (ZIs) and evaluate their clinical effectiveness. The study includes patients who were treated at a dental clinic in Italy from 2012 to 2022. These patients received fixed screw-retained complete dentures supported by either two or four zygomatic implants (ZIs). The patients underwent a minimum one-year follow-up post-loading, following two protocols: the hybrid and the quad protocol. Digital planning incorporated CBCT scans, intraoral scans, and digital prosthetic plans within implant planning software. Surgical techniques involved extended sinus lift and extramaxilla techniques methods, utilizing the ZAGA approach for ZI placement. The results showed that out of 19 patients with a mean age of 65.3, a total of 56 zygomatic implants (ZIs) and 20 standard implants were used, with no failures observed in either the implants or the definitive prostheses, resulting in a 100% survival rate. According to the ORIS criteria, overall success was achieved in terms of implant stability, sinus health, peri-implant soft tissue condition, and prosthetic function. Only two ZIs (3.6%) exhibited minor gingival recession and moderate thread exposure, which were closely monitored through professional hygiene maintenance. Both the extended sinus lift and extramaxilla protocols demonstrated comparable clinical outcomes and minimal complications in the restoration of severely atrophic maxillae with Zygomatic Implants (ZIs). However, further extensive studies involving larger, multicenter designs and longer follow-up periods are needed to validate and refine these outcomes.

Application of Ultrashort Implants in Posterior Maxilla With Insufficient Bone Height: A Finite Element Analysis.

Implantation of the posterior maxilla with insufficient bone height faces challenges. Studies have shown that the use of ultrashort implants can avoid additional damage. This finite element analysis study aimed to evaluate the impacts of different lengths of ultrashort implants and three surgical approaches on stress, strain, and displacement in the posterior maxilla with varying bone heights. Twelve models of different lengths (3.0, 4.0, 5.0, and 6.0 mm) of ultrashort implants combined with unicortical fixation, bicortical fixation, and transalveolar sinus elevation were established, and conventional implants and short implants were considered as control models. Von Mises stresses within the implants and the sinus floor cortical bone, maximum and minimum principal stresses within the alveolar ridge cortical bone, and the maximum principal strain of the cancellous bone were determined using these models. Additionally, the displacement of the implants was analysed. Stress distribution range and peak values increased as implant length decreased. In the ultrashort implant group, H5L6 exhibited the smallest maximum and minimum principal stresses, 35.77 and 10.66 MPa, respectively. Among groups with different bone heights, 6 mm long implants presented the lowest maximum von Mises stress, whereas 3 mm long implants presented the highest. In the posterior maxilla with bone heights of 3, 4, and 5 mm, the stresses in different lengths of ultrashort implants and surrounding bone tissue were lower than the yield strengths in these areas, and the use of 6 mm-long ultrashort implants combined with osteotome sinus floor elevation can achieve lower stress distribution. This study provides important insights into the biomechanical properties of ultrashort implants combined with three different surgical procedures in severely atrophic maxilla. The 6-mm long implant combined with osteotome sinus floor elevation is most suitable for this area.

Maxillary sinus floor elevation with autologous platelet derivatives and bone grafting techniques: a narrative review

This review explores the utilization of platelet-rich products—platelet-rich plasma (PRP), platelet-rich fibrin (PRF), and concentrated growth factors (CGF)—in maxillary sinus floor elevation (MSFE) as a means of enhancing bone regeneration for dental implant placement. Tooth extraction frequently leads to bone loss, making augmentation essential for the success of implant-supported rehabilitation. MSFE is a common approach to restoring bone volume in the atrophic posterior maxilla. Still, limitations like restricted graft availability and the risks associated with autogenous bone harvesting have spurred interest in alternative solutions. Platelet concentrates derived from the patient’s blood, including PRP, PRF, and CGF, are abundant in growth factors such as VEGF, PDGF, and TGF-β1, which play critical roles in promoting osteogenesis, angiogenesis, and tissue repair. Among these, CGF, recognized as a third-generation platelet concentrate, exhibits superior regenerative capabilities for soft and hard tissues due to its denser fibrin matrix, surpassing PRP and PRF in performance. Combining platelet concentrates with bone graft materials has been shown to enhance regeneration, with studies highlighting the efficacy of PRP alongside xenografts or demineralized bovine bone. Furthermore, surgical techniques like the lateral window approach and adaptations such as Summer's osteotomy contribute significantly to procedural outcomes. Despite promising clinical results, further research is needed to optimize protocols, enhance cost-efficiency, and streamline procedures.

CGF with Bio-Oss collagen as grafting materials for simultaneous implant placement after osteotome sinus floor elevation: a prospective study

BackgroundOsteotome sinus floor elevation (OSFE) procedure with simultaneous implant placement is known to be an efficient procedure in the atrophic maxilla, where bone regeneration is required the most. The purpose of this study was to radiologically evaluate the efficacy of using Bio-Oss Collagen with Concentrated Growth Factor (CGF) as grafting materials for OSFE with simultaneous implant placement in the atrophic maxilla after one year of functional loading.MethodsA total of 126 implants were placed for 123 patients. Our inclusion criteria were patients with Residual Bone Height (RBH) ≤ 5 whom underwent OSFE procedure and simultaneous implant placement with different grafting materials: Group A with no grafting materials, Group B with Bio-Oss bone graft, and Group C with Bio-Oss Collagen with CGF. The Implants Survival Rate (ISR) was the primary outcome variable. Secondary outcome variables included radiographic measurements assessed at four follow-up time points, the Implant Stability Quotient (ISQ), and bone density (B). Indicators of bone formation were compared at different time points. Appropriate statistical analyses were conducted, with statistical significance set at a P value of 0.05 for all tests.ResultsISR was 96%. A significant positive relationship was found between RBH and ISR, [r (126) = .359, p = .000]. Endo sinus bone gain indictors increased in both grafted groups as compared to the non-grafted group. Total Bone Resorption (TBR1) and (TBR2) significantly decreased in both grafted groups compared to the non-grafted group (P = .004, P = .000). Graft size (D) was a positive predictor for ISR at three time points: D0 (odds ratio [OR] 8.06; 95% CI 1.59 to 38.24; P = .010); D1 (OR 96.58; 95% CI 1.69 to 5.52; P = .027); D2 (OR 4.97; 95% CI 1.29 to 19.19; P = .020). Visual Analog Scale (VAS) pain score significantly increased in Group B compared to Groups A and C (P = .000).ConclusionThe combination of Bio-Oss Collagen with CGF as grafting material is a reliable protocol after OSFE with simultaneous implant placement in the atrophic maxilla. This approach is accompanied by high patient satisfaction.

Management of adverse effects following additively manufactured subperiosteal jaw implantation in the maxilla.

This expert opinion presents provisional guidelines for addressing complications associated with Additively Manufactured Subperiosteal Jaw Implants (AMSJI®) in patients with severe maxillary atrophy. AMSJI®'s custom design, supported by finite element analysis (FEA), allows precise placement that avoids critical anatomical structures and minimizes complications relative to alternative solutions. Data were gathered through firsthand experiences, direct communications, and insights from international workgroup meetings. Minor complications, such as soft tissue recession with inflammation, can be managed through thorough patient selection and early intervention. Severe complications, such as ascending infections and mechanical issues (e.g., fractures of implant components), have been rare. Compared to zygomatic implants and bone grafting, AMSJI® demonstrates a favorable safety profile. Zygomatic implants may lead to severe issues like orbital cellulitis and diplopia, while bone grafting risks include graft resorption, loss, and donor site complications. To mitigate these risks, selecting patients carefully and ensuring diligent follow-up are critical, especially in those with risk factors like smoking or bruxism. Improved imaging, planning, and FEA have further contributed to minimizing complications, reinforcing AMSJI®'s role in complex maxillary reconstructions and implant-supported prosthetics. AMSJI® demonstrates high success rates but requires meticulous risk management. Key strategies involve carefully candidates by excluding those who are smokers, immunocompromised, or non-compliant, or diabetics with a history of infectious complications. Additionally, strict adherence to oral hygiene protocols is essential to optimize outcomes and minimize risks.Proactive management in these areas is crucial to optimize outcomes, ensure implant longevity, and support successful prosthetic rehabilitation.

Sinus Bone Graft Stability and Implant Survival Following Transalveolar Sinus Floor Elevation in Severely Atrophic Maxilla: A Retrospective Study With 5-8 Years of Follow-Up.

To evaluate the clinical and radiographic results of transalveolar sinus floor elevation (TSFE) with grafting in cases of severely atrophic maxilla. A retrospective analysis of clinical and radiographic data was conducted. Between 2015 and 2018, a total of 105 implants were placed in 105 patients over a follow-up period of 5-8 years. Implant failures and endo-sinus bone gain (ESBG) were assessed. Statistical models were established to investigate the potential influencing factors of implant survival and ESBG. Six patients with six implants were lost, resulting in cumulative survival rates of 94% for both patient- and implant-based analyses. The 8-year cumulative survival rate was significantly lower for residual bone height (RBH) < 4 mm (88%) compared to RBH 4-6 mm (98%). ESBG ≥ 4 mm and ESBG ≥ 6 mm were observed in 89.90% and 58.59% of implant sites, respectively. According to the log-rank Mantel-Cox analysis results, none of the factors examined were significantly related to implant failure, except for RBH (p = 0.038) at baseline. The linear mixed-model regression results showed that the final ESBG was positively correlated with implant insertion site (p = 0.003), implant length (p < 0.001), sinus floor elevation (SFE) methods (p = 0.010), and RBH (p < 0.001). Within the limitations of this study, it has been established that TSFE with grafting was a reliable method for implant placement in the posterior atrophic maxilla ridges with RBH ranging from 4 to 6 mm. Nevertheless, caution was advised when considering its application in cases where the initial bone height falls below 4 mm.

Hybrid Full-Arch Rehabilitation Using Conventional And Zygomatic Implants: A Short-Term Retrospective Analysis.

To report one-year outcomes of prosthetic rehabilitation of the atrophic maxillae, supported by angled abutments on zygomatic implants and conventional implants. In the present retrospective analysis, edentulous maxillary areas treated with fixed-hybrid prostheses supported by angled abutments of 45, 52.5, and 60 degrees screwed to zygomatic implants inserted using an extrasinus surgical approach were included. Prosthesis, implant, and abutment success/survival rates, complications, Mucosal Seal Efficacy Evaluation (MSEE), modified PLaque Index (mPLI), modified Bleeding Index (mBI), and Zygomatic Implants Classification Level (ZICL) were assessed. Ninety-eight straight implants and 81 zygomatic implants (21 abutments of 45 degrees, 23 of 52.5 degrees, and 37 of 60 degrees) were inserted into 35 patients. Biological complications: postoperative sinus opacity was observed in seven patients, two of whom experienced a unilateral perforation of the sinus membrane. ZICL0-1 was recorded in 95% of zygomatic sites; the cumulative success rates were 100% and 94.3% when using the implant and prosthesis as units of analysis, respectively. Survival rate for the implants attested to the highest percentage (100%), whereas survival rate of the prostheses was 94.3%. No differences were registered among the clinical indices related to different inclinations of the abutments.

Finite element analysis of zygomatic implant positioning protocols with conventional implant configurations

The aim of finite element analysis (FEA) study was to compare two zygomatic implant (ZI) techniques in combination with conventional implants. A FEA model was constituted based on computed tomography data of a patient. ZIs were virtually placed into models with sinus slot or extra sinus techniques combined with two or four conventional implants. Occlusal forces were applied from the buccal direction. The von Mises stress values in implants and the principal stress values in alveolar bone were analyzed. Four conventional implants and the sinus slot technique showed lower stress values. Two ZIs with the sinus slot technique and four conventional implants may be biomechanically safer for atrophic maxilla rehabilitation.

QUAD ZYGOMA: Rehabilitation of severe maxillary atrophy with Zygomatic implants and immediate loading. Case report.

QUAD ZYGOMA: Rehabilitation of severe maxillary atrophy with Zygomatic implants and immediate loading. Case report.

Complications during the installation of zygomatic implants: Clinical challenges and management

Zygomatic implants have become a highly effective alternative for oral rehabilitation in patients with severe maxillary atrophy, offering a durable and functional solution when other methods, such as bone grafts, are not feasible. However, the installation of zygomatic implants presents various technical and clinical challenges. Intraoperative complications during the procedure may compromise osseointegration and increase the risk of adverse outcomes. This article aims to review the primary complications associated with zygomatic implant installation, examining their causes, diagnosis, prevention, and management. Through a literature review, the paper explores the complexities of the procedure and emphasizes the importance of a meticulous approach to minimize risks and optimize outcomes.

Long-Term Success of Dental Implants in Atrophic Maxillae: A 3-Year Case Series Using Hydroxyapatite and L-PRF.

Dental implants are essential for the prosthetic rehabilitation of edentulous patients, requiring adequate bone volume and density for osseointegration and load support. The posterior region of the maxilla, commonly deficient in bone quality and quantity, represents a clinical challenge. This case series reports an analysis involving 69 dental implants in the atrophic maxilla of nine patients. The procedures adopted combined alloplastic hydroxyapatite grafting and leukocyte platelet-rich fibrin (L-PRF) applied to the alveolar ridge and maxillary sinus lift. With an average follow up of three years after the installation of the prostheses, an implant success rate of 98.5% was observed, showing integration and functional stability. The strategy of combining hydroxyapatite with L-PRF proved to be effective in increasing bone volume and promoting osseointegration. These findings indicate that the technique and biomaterials are viable for rehabilitating atrophic maxillae in the posterior region, offering long-lasting clinical results and a high success rate.

Avoiding Unwanted Exposure of Subperiosteal Implants in the Atrophic Maxilla: Technical Note.

The use of subperiosteal implants for the rehabilitation of atrophic maxillae has taken attention recently as a validated option in the treatment of severe atrophy. The systems have been improved by technological advancements and the analysis of variables affecting their prognosis. However, one of the most frequent issues to resolve is the unwanted exposure of a portion of the metal mesh close to the abutment and prosthetic connections, which can result in infections, hygiene problems, and, in some instances, complete failure. It seems that the surgical approach is a hot topic for the success of these implants. This article describes a surgical technique that lowers the risk of unintended implant exposure by enabling the subperiosteal implant to be installed from the lateral approach and enabling the right access to the prosthetic abutments in a transfixing way from palatal approach, away from the primary surgical access.

Eazygoma technique: a new approach for zygomatic implant placement aligned with maxillomalar anatomy

This study focused on evaluating the novel Eazygoma method for zygomatic implant placement. This approach focuses on biomechanical principles, offering direct visualization that facilitates enhanced control during implant insertion. It helps prevent malpositioning, ensuring that the apical portion remains within the zygomatic body and achieves emergence in the alveolar crest through an inverted drilling sequence. The Eazygoma system enables improved control during drilling, starting in the zygomatic area and eliminating the need for osteotomies in the maxillary sinus. This not only simplifies the procedure but also significantly reduces the operative time, allowing it to be performed under local anesthesia and sedation in approximately one hour, according to the author’s experience. The study included 34 zygomatic implants placed in 11 patients with severe maxillary atrophy, treated between 2021 and 2023 at the Maxillofacial surgery Department of the private clinic “Clínica Colsanitas” in Bogotá, Colombia. To evaluate outcomes, intraoperative torque, surgical time, and whether alveolar emergence was achieved were measured for the implants. Patients were followed up at 12 months to assess implant survival. Results showed that the Eazygoma approach eliminated postoperative sinus injuries and implant malposition, ensuring alveolar emergence and achieving a torque greater than 50 Newtons in all cases, allowing for immediate implant loading.

The Rehabilitation of Partially Edentulous Maxilla With Unilateral Zygomatic Implants: A Retrospective Study up to 23 Years Follow-Up.

This retrospective study aimed to evaluate the clinical outcomes associated with zygomatic implant (ZI) rehabilitation in partially atrophic edentulous maxillae over a mean follow-up period of more than 10.3 years. All consecutive patients underwent ZI rehabilitation between 1999 and 2020, with a minimum follow-up period of 3 years. The primary outcome was the implant survaival rate. Secondary outcomes included the prosthesis success rate, complications, and Oral Health-Related Quality of Life. Of the 21 patients, treated with 27 ZIs and 48 conventional implants (CIs), 9 (42.9%) were females. The mean follow-up was 10.3 ± 5.7 years (range 3.2-23.4). ZI and CI survival rates were 100% and 97.9%, respectively, with one CI that failed. Eleven patients received 12 CIs placed in the pterygoid and tuberosity region. Most of the implants (81.33%) were immediately loaded, with 17 patients (80.9%) receiving 21 acrylic bridges. Of the total of 26 definitive prosthesis, the success rate was 96.1%. Local inflammation (n = 2) and soft tissue recession (n = 1) were reported as complications, occurring at a mean follow-up of 4.5 and 3.2 years, respectively. The mean score of the OHIP-14 questionnaire was 1.19 ± 1.99. Unilateral ZI rehabilitation was a predictable option for patients with partially atrophic edentulous maxilla who have experienced previous graft or implant failures, or who require immediate loading. Splinting the ZI with CI for restoration appeared to be essential in unilateral ZI treatment. Complications were infrequent and could be managed effectively, with patient-reported outcomes indicating normalization in quality of life.