Long-term treatment outcomes with zygomatic implants: a systematic review and meta-analysis.

PURPOSE: The purpose of this study was to perform a systematic review with meta-analysis on the long-term survival rates of zygomatic implants (ZI). ZI success, prostheses survival and success, sinus pathology and patient reported outcomes were also investigated. METHODS: Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines were followed. Embase and OvidMedline databases were searched alongside the grey literature. The systematic review was recorded in PROSPERO (CRD42022358024). Studies reporting titanium/titanium alloy ZI survival data, ZI-supported prosthesis data, ZIs directly compared to any other implant therapy including grafted sites, a minimum follow-up time of 3 years and a minimum number of 10 patients were included. All study designs were considered if they met the inclusion criteria. Studies not involving ZIs, ZIs not made from titanium/titanium alloy, a follow-up time of < 3 years or < 10 patients, animal studies and in vitro studies were excluded. Long-term follow-up has not been defined in the literature. A minimum of 3 years follow-up was considered acceptable to capture survival after initial healing, alongside in-function prosthesis data via delayed or immediate load protocols. ZI success, was predominantly defined as ZI survival without biological or neurological complications. Meta-analyses were performed for ZI survival, ZI failure incidence, ZI success, loading protocol, prosthesis survival, and prevalence of sinusitis using random effects models. Descriptive analysis was used for ZI success, prosthesis success and patient reported outcome measures. RESULTS: Five hundred and seventy-four titles were identified, of which 18 met the inclusion criteria. Eligible studies included 1349 ZIs in 623 patients. Mean follow-up period was 75.4 months (range 36-141.6). The mean survival of ZIs was 96.2% [95% CI: 93.8; 97.7] at 6 years. Mean survival for delayed loading was 95% [95% CI: 91.7; 97.1] and 98.1% [95% CI: 96.2; 99.0] for immediate loading (p = 0.03). Annual incidence rate of ZI failure was 0.7% [95% CI 0.4; 1.0]. Mean ZI success was 95.7% [95% CI 87.8; 98.6]. Mean prosthesis survival was 94% [95% CI 88.6; 96.9]. Sinusitis prevalence was 14.2% [95% CI 8.8; 22.0] at 5 years. Patients' reported increased satisfaction with ZIs. CONCLUSIONS: ZIs have long-term survival comparable to conventional implants. Immediate loading showed a statistically significant increase in survival over delayed loading. Prosthesis survival was similar to that of prostheses supported by conventional implants, with similar complications. Sinusitis was the most frequently encountered biological complication. Patients reported improved outcome measures with ZI use.

Catastrophic implant failure after immediate loading of full arch implant prosthesis and its association with CPAP therapy: A case report.

Full arch implant-supported restorations are a common treatment modality for patients with a terminal dentition or an edentulous mouth. Several mechanical and biological factors that contribute to complications or failure are already extensively documented. Some patients receiving complex implant-based treatment plans also suffer from obstructive sleep apnea (OSA). The use of a continuous positive airway pressure (CPAP) mask in some of these patients is a lesser-known factor that could contribute to implant complications or failures. This article describes how the use of a CPAP machine may be a risk factor in implant dentistry and describes a patient whose use of a CPAP machine and mask led to a catastrophic failure of mandibular full arch dental implants.

9-Year Follow-Up on Maxillofacial Implant-Supported Framework Designed to Accommodate Childhood Growth.

This clinical report focuses on the challenges and solutions for a child subjected to craniofacial trauma from a wild hyena biting off his nose and anterior maxilla. Unique considerations in prosthodontics and biomedical engineering were required based on future craniofacial growth and development of the child. The physical requirement of a maximum retentive prosthesis for an active, athletic child required unique engineering designs and executions. The sequence of treatment and prosthesis fabrication are detailed. The patient has been followed for 9 years without physiologic complications and only minor prosthodontic complications.

Identification of the Pathway and Appropriate Use of Four Zygomatic Implants in the Atrophic Maxilla: A Cross-Sectional Study.

PURPOSE: This cross-sectional study aimed to identify and characterize the pathway for appropriate placement of four zygomatic implants in the severely atrophic maxilla and to group the anatomical variations of the osteotomy trajectory for anterior zygomatic implants. MATERIALS AND METHODS: CBCT images of patients presenting indications for the use of four zygomatic implants to withstand a maxillary rehabilitation were reviewed. Cross-sectional planes corresponding to the implant trajectories, designed according to a zygoma anatomy-guided approach for implants placed in the anterior and posterior maxilla, were assessed separately. The relationship of the implant osteotomy trajectory with the correlated residual alveolar bone, nasal and sinus cavities, maxillary wall, and zygomatic bone anatomies was established. RESULTS: The study population included 122 globally recruited patients, with 488 zygomatic implants, 244 of which had their starting point on the anterior incisor-canine area and 244 on the posterior premolar-molar area. The anatomy of the osteotomy path designed for the anterior implants ("A") was named and grouped into five assemblies from zygomatic anatomy-guided ZAGA A-0 to A-4, representing 2.9%, 4.5%, 19.7%, 55.7%, and 17.2% of the studied sites. Percentages for posterior implant ("P") trajectories of the osteotomy were grouped and named as ZAGA P-0 to P-4, representing 5.7%, 10.2%, 8.2%, 18.4%, and 57.4% of the sites, respectively. Approximately 70% of the population presented anatomical intra-individual differences. CONCLUSION: The trajectory of the zygomatic implant followed different anatomical pathways depending on its coronal point being anteriorly or posteriorly located, which justifies a new zygoma anatomy-guided approach classification for anteriorly placed zygomatic implants. Topographic characteristics of the anatomical structures that are cut by an anterior oblique plane joining the lateral incisor-canine area to the zygomatic bone, representing the planned anterior osteotomy path in a quadruple-zygoma indication, have not been previously reported. Adaptation of surgical procedures and implant sections/designs to individual patients' anatomical characteristics is essential to reduce early and long-term complications.

Incidental Findings in Cone Beam Computed Tomography for Dental Implants in 1002 Patients.

PURPOSE: The purpose of this study is to analyze the frequency and elevate the awareness of the prevalence of nondental pathology in cone beam computed tomography (CBCT) scans taken for implant placement treatment planning and postplacement evaluation. The data from the CBCT should be read by an oral and maxillofacial radiologist for proper diagnosis of dental and nondental pathology and referred to the medical specialist for proper management when necessary. MATERIALS AND METHODS: This retrospective study analyzed 1002 consecutive CBCT scans taken at a single private practice noting the prevalence of nondental pathology in CBCT images for all dental implant procedures. All scans were taken from November 2007 to March 2020. One board certified oral and maxillofacial radiologist systemically read all scans and reported all findings in the maxilla and mandible, condyles and TMJ, paranasal sinuses, nasal fossa, pharyngeal airway, skull base and temporal bone, neck soft tissues, and cervical spine. The incidental findings, variation of normal anatomy, or pathology reported in these structures were categorized based on anatomic location and significance and the incidence was investigated. RESULTS: Pathologies ranged from innocuous sinusitis, to more serious atherosclerotic calcification of the carotid arteries, narrowed airways, and neoplastic lesions. Fifty-one different findings were noted, of which 36 were pathologies that required referral or follow-up. CONCLUSIONS: Incidental findings can be detected in CBCT scans for dental implants. The clinician must be familiar with the radiographic diagnosis of head and neck pathology, and/or must refer these images to an appropriate specialist for the radiographic interpretation of the full volume.

Decision Process in Treatment of Reduced Periodontium: A Case Report.

The relationship between attachment loss and occlusal trauma has been debated for many years. When a patient presents with advanced periodontal disease, a decision has to be made on whether the teeth can be saved or extracted. In this treatment example, the decision process in therapeutic planning for a patient with stage IV periodontal disease is discussed. The main dilemma is whether the patient should receive a prosthodontic reconstruction supported by osseointegrated implants or by periodontally compromised natural teeth. It is assumed that implants do better than teeth over the long term based on firm documentation in the literature, but this article describes why a periodontal prosthesis is still a viable treatment option.

Management of Maxillary Cluster Implant Failures with Extra-Maxillary Implants: A Clinical Report.

Late cluster implant failures can be one of the most devasting outcomes of implant therapy for patients. It can have anatomic, functional, psychological and financial consequences for patients, and sometimes the loss of residual bone can preclude subsequent implant placement. Fortunately, management of cluster implant failures in the maxilla can be mitigated by using implant anchorage from remote sites like zygomatic and pterygoid regions. Few reports exist in the literature that have described the management of cluster implant failure using extra-maxillary implants such as zygomatic and pterygoid implants. This case report describes the management of a female patient with bruxism who experienced late cluster implant failure in the maxilla after 9 years of function with an overdenture. Due to the loss of residual bone, subsequent implant therapy involved the use of bilateral zygomatic, pterygoid and anterior maxillary implants, which were immediately loaded and thereafter used to support a complete arch fixed implant-supported zirconia prosthesis.

Evolution of Full-Arch Implant Prosthodontics: From Analog Protocols to Digital Workflows.

Ever since orthopedic research emanating from Sweden revealed that human bone could consistently fuse to titanium, forward-thinking prosthodontists have pursued the enormous possibilities for restoring patients with implant-supported prosthodontics. Applications for osseointegration in full-arch prosthetic dentistry have evolved, with the chronologic development of technique and technology progressing from multi-step complex analog procedures to streamlined digital production of immediately loaded prosthetic dentitions that predictably deliver restorative excellence. This article presents a historical perspective that describes how dental implant prosthodontic materials and methods have advanced and are effectively keeping pace with other medical disciplines while remaining entrenched in scientifically based methodology. The article discusses current methods available for producing desirable prosthodontic treatment results to provide patients healthy, esthetic, enduring rehabilitations. The authors conclude that a wealth of research and experience has contributed to the progress of implant prosthodontics and that, based on current technological advances, this area of dentistry is only at the cusp of further development.

Management of Biotechnical Complications Associated with a Full-Arch Implant Restoration Using Digital and Conventional Workflows: A Clinical Report.

Full-arch implant-supported restorations using a metal-acrylic resin design have had a high success rate but are also associated with frequent technical complications including framework misfit due to casting errors, debonding of denture teeth, and fracture of the acrylic from the metal framework. This clinical report describes a case of maxillary and mandibular full-arch implant-supported rehabilitation associated with technical and biological complications and use of digital technology for fabricating monolithic restorations. The use of a bio-functional try-in and its subsequent use as a conversion prosthesis for fabricating a master cast is described. The use of the patient's existing metal bar to fabricate a retread type prosthesis is also described along with using digital technology for fabricating a new metal bar and a monolithic type of restoration. The integration of digital and conventional workflows to obtain an increased level of accuracy and simplicity is also discussed.

A 30-Year Follow-Up of a Patient with Mandibular Complete-Arch Fixed Implant-Supported Prosthesis on 4 Implants: A Clinical Report.

Mandibular complete-arch fixed implant-supported prostheses are recognized as one of the earliest and most popular prostheses in implant dentistry. This prosthesis was the main focus in the early era of osseointegration. Despite its widespread popularity, few clinical reports have described long-term follow-up greater than 10 years for this type of prosthesis. This report describes a 30-year follow-up of a patient who underwent treatment for a mandibular complete-arch fixed implant-supported prosthesis with 4 machined surfaced implants, opposing a maxillary complete denture. This report documents a variety of photographs and radiographs taken over a period of 30 years to compare bone levels at various stages of care and maintenance, including de novo bone formation underneath the distal cantilevers due to functional loading. The biologic and biomechanical response to this treatment protocol and long-term clinical observations and prosthodontic outcome and maintenance needs are also addressed.

Thirty-Two-Year Success of Dental Implants in Periodontally Compromised Dentition.

Osseointegrated dental implants have become an integral factor in the replacement of missing teeth. These implants have demonstrated long-term success for periodontally compromised patients, who require a high level of success to maintain a sense of optimism. This case report offers 32-year results of implant treatment in the maxilla and 25-year results in the mandible. Some maxillary implants suffered a few threads of bone loss, but all seven mandibular implants met Albrektsson's definition of success after 25 years. The purpose of this case report is to provide evidence that further supports the findings of osseointegrated implant treatment's longevity and success, as reported in other studies.

The Retread: A Definition and Retrospective Analysis of 205 Implant-Supported Fixed Prostheses.

PURPOSE: Acrylic resin teeth on fixed implant prostheses are subject to time-dependent wear. The purpose of this retrospective analysis is to evaluate and describe the management of such wear in the context of selected variables--patient gender and age, dental arch location, and opposing dentition. The clinical and dental laboratory process to replace the worn teeth is defined as a retread. MATERIALS AND METHODS: A retrospective database review from a single private prosthodontic practice was carried out on all patients who had undergone a retread procedure. The patient pool included 205 arches in 194 patients (70 in men, 135 in women) with a mean age of 57.4 years (range: 19.9 to 80.5 years). The retread procedure is described. RESULTS: The mean time between final prosthesis delivery and retread was 7.8 years (range: 1.1 to 22.9 years). Statistical analysis was significant according to dental arch and opposing dentition. A statistical difference was also noted in patients undergoing multiple retread procedures, with a reduction in time between the subsequent procedures. CONCLUSION: Acrylic resin components of implant-supported hybrid prostheses wear over time and are influenced by a combination of the nature of the opposing dentition and patient habits. The dental laboratory process to retread the implant-supported framework is important for long-term patient care and maintenance of an appropriate vertical dimension of occlusion.

Positioning handle and occlusal locks for the Teeth-in-a-Day protocol.

Positioning handles and occlusal locks have evolved as improvements to the Teeth-in-a-Day protocol. These improvements have enabled a more accurate alignment of the removable dental prosthesis during the conversion prosthesis technique. These improvements can be easily incorporated through computer-aided design and computer-aided manufacturing digital denture fabrication process.

A long-term retrospective analysis of survival rates of implants in the mandible.

PURPOSE: To retrospectively analyze the survival rate of endosseous dental implants placed in the edentulous or partially edentulous mandible over a long-term follow-up period of 10 years or more. MATERIALS AND METHODS: The charts of patients who underwent mandibular implant placement at a private prosthodontics practice and received follow-up care for 10 years or more were included in this study. Implants were examined according to the following study variables: patient sex, patient age, degree of edentulism (fully vs partially edentulous), implant location, time of loading (delayed vs immediate), implant size and type, bone quality, prosthesis type, and the presence of other implants during placement. RESULTS: The study sample was composed of 2,394 implants placed in 470 patients with 10 to 27 years of follow-up. Of these 2,394 implants, 176 failed, resulting in an overall cumulative survival rate (CSR) of 92.6%. A total of 1,482 implants were placed in edentulous mandibles, and 912 implants were placed in partially edentulous mandibles, with CSRs of 92.6% and 92.7%, respectively. Comparisons of the study variables with respect to CSR were largely nonsignificant. However, there were significant differences in CSRs between anterior vs posterior locations and rough- vs smooth-surfaced implants in addition to some prosthesis types, ages, and bone qualities. The overall CSR of 92.6% in the present study is high and comparable to survival rates observed in previous long-term analyses of mandibular implants. The significant differences observed between implant locations, patient age groups, bone qualities, and prostheses were not suggestive of any remarkable trends. CONCLUSION: Patient sex, age, degree of edentulism, implant location, time of loading, implant size and type, bone quality, prosthesis type, and the presence of multiple implants did not result in any significant effect on long-term implant survival. The CSR observed after 10 to 27 years of follow-up in a single private prosthodontic center was high (92.6%) and supports the use of endosseous dental implants as a long-term treatment option for the rehabilitation of the edentulous and partially edentulous mandible.

Fabricating an Accurate Implant Master Cast: A Technique Report.

The technique for fabricating an accurate implant master cast following the 12-week healing period after Teeth in a Day® dental implant surgery is detailed. The clinical, functional, and esthetic details captured during the final master impression are vital to creating an accurate master cast. This technique uses the properties of the all-acrylic resin interim prosthesis to capture these details. This impression captures the relationship between the remodeled soft tissue and the interim prosthesis. This provides the laboratory technician with an accurate orientation of the implant replicas in the master cast with which a passive fitting restoration can be fabricated.

Oral rehabilitation and psychosocial evaluation of a patient with bulimia nervosa following Teeth in a Day® immediate loading protocol.

PURPOSE: The purpose of this patient report is to accurately portray the clinical experience of treating an active bulimic patient by employing an immediately loaded dental implant protocol to provide the patient with an expedited esthetic and functional result. Implementation of a psychometric component statistically quantifies the psychological effects of the oral rehabilitation. MATERIALS AND METHODS: A 34-year-old woman presented with severe dental perimolysis (erosion) resulting from a 28-year history of bulimic behaviors. Clinical and radiographic evaluation of the existing dentition indicated advanced dental erosion and previous restoration attempts in a state of failure. The patient's existing teeth were extracted and treated with full maxillary and mandibular implant-supported prostheses, following the Teeth in a Day® (TIAD) immediate functional loading protocol. Psychometric assessment was conducted through administration of a 20-item questionnaire, as seen in previous literature. RESULTS: Radiographic and clinical analysis suggested all implant fixtures to be viable and accompanied by normal levels of alveolar bone 7 months into treatment. Questionnaire results at the new-patient presentation (T1) resulted in a composite score of 4.0 (SD = 2.9; P = 0.004), indicating severe body-image dysphoria. At 3 months postoperative (T2), the questionnaire score was 0.4 (SD = -1.7; P = 0.09). The final psychometric questionnaire at 7 months (T3) resulted in a score of 0.5 (SD = -1.5; P = 0.12). The patient was followed for a total of 7 years following implant placement. CONCLUSION: In this patient report, oral rehabilitation using the TIAD protocol provided an expedited and predictable alternative method for restoring functional abilities, esthetics, and self-esteem to a severely depressed bulimic patient. Psychometrically, at the postoperative (T2) and final testing period (T3), the patient's body image profile was no longer considered to be significantly different from established normative values.

Management of soft tissue irritation around exposed zygomatic implant in a hemimaxillectomy patient: a technical report.

Patients missing portions or all of the maxillary alveolar bone who are restored with zygomatic implants frequently have threads exposed that can be a mucosal irritant. If such irritation is reported, covering the threads with a highly polished titanium sleeve is recommended. The technique of placing said custom sleeve is described. This adjunctive treatment method has eliminated mucosal irritation.

Etiology and treatment of periapical lesions around dental implants.

The widespread use of oral implants in recent years has resulted in various types of complications. One of those complications is the periapical implant lesion. Different factors have been proposed to play a role in the development and emergence of a periapical implant lesion. To date, there is no consensus on the etiology and therefore periapical lesions around dental implants are considered to have a multifactorial etiology. The diagnosis of an implant periapical lesion should be based on both clinical and radiological findings. Additionally, in order to apply the best treatment strategy the evolution of the lesion should be taken into account. The treatment of this kind of lesion, however, is still empiric. Data, primarily from case reports, seem to indicate that the removal of all granulation tissue is a first step to arrest the progression of the bone destruction. The removal of the apical part of the implant seems a valuable treatment strategy.

Zygomatic implants as a rehabilitation approach for a severely deficient maxilla.

A gunshot injury is one of the main trauma injuries that affect the head and neck region. Severe esthetic, functional, and psychologic deficiencies are consequences of gunshot injuries. The use of implants anchored in the zygomatic bone has been advocated as an approach to the prosthetic rehabilitation of a severely deficient maxilla. This approach provides the patient with an immediate, high-quality, esthetic, and functional complete fixed prosthesis and eliminates the need for bone grafting. In this case report, a patient with a severely deficient maxilla caused by a gunshot injury was rehabilitated by placement of four zygomatic and two pterygomaxillary implants, which were immediately loaded with a complete fixed all-acrylic resin interim prosthesis. The definitive CM Prosthesis (CM Prosthetics) was constructed using computer-aided design/computer-assisted manufacture (CAD/CAM) technology.