Accuracy of digital planning in zygomatic implants

Abstract Background Zygomatic implants have been described as a therapeutic alternative for patients with severe maxillary atrophy in order to avoid bone augmentation procedures. Taking that into account, in these treatments, the key factor is the position of the implant, the virtual surgical planning (VSP) is widespread among most clinicians before surgery on the patient. However, there are no studies which evaluate the clinical relevance of these VSP. The aim of this study is to determine whether digital planning on zygomatic implants has any influence on the implant dimensions and position, even when performing conventional surgery afterwards. Results Fourteen zygomatic implants were placed in four patients. Pre-operative and post-operative helicoidal computed tomography were performed to each patient to allow the comparison between the digital planning and the final position of implants. Tridimensional deviation (TD), mesio-distal deviation (MDD), bucco-palatine deviation (BPD), and apico-coronal deviation (ACD) were evaluated as well as angular deviation (AD). Significative differences in apical TD were observed with a mean of 6.114 ± 4.28 mm (p < 0.05). Regarding implant position, only implants placed in the area of the first right molar reported significant differences (p < 0.05) for ACD. Also, implant length larger than 45 mm showed BPD significative differences (p < 0.05). Conclusions Zygomatic implant surgery is a complex surgical procedure, and although VSP is a useful tool which helps the clinician determine the number and the length of zygomatic implants as well as its proper position, surgical experience is still mandatory.

Download Full-text

Dynamic Navigation for Zygomatic Implants: A Case Report about a Protocol with Intraoral Anchored Reference Tool and an Up-To-Date Review of the Available Protocols

Methods and Protocols ◽

10.3390/mps3040075 ◽

2020 ◽

Vol 3 (4) ◽

pp. 75

Author(s):

Gerardo Pellegrino ◽

Giuseppe Lizio ◽

Francesco Basile ◽

Luigi Vito Stefanelli ◽

Claudio Marchetti ◽

...

Keyword(s):

Navigation Systems ◽

Radiological Anatomy ◽

Implant Placement ◽

Zygomatic Implants ◽

Dynamic Navigation ◽

Operative Planning ◽

Placement Accuracy ◽

Zygomatic Implant ◽

Maxillary Atrophy ◽

Reference Tool

Dynamic Navigation is a computer-aided technology that allows the surgeon to track the grip instruments while preparing the implant site in real time based on radiological anatomy and accurate pre-operative planning. The support of this technology to the zygoma implant placement aims to reduce the risks and the errors associated with this complex surgical and prosthetic treatment. Various navigation systems are available to clinicians currently, distinguished by handling, reliability, and the associated economic and biological benefits and disadvantages. The present paper reports on the different protocols of dynamic navigations following a standard workflow in correlation with zygomatic implant supported rehabilitations and describes a case of maxillary atrophy successfully resolved with this technology. An innovative and minimally invasive dynamic navigation system, with the use of an intraoral anchored trust marker plate and a patient reference tool, has been adopted to support the accurate insertion of four zygomatic implants, which rapidly resolved maxillary atrophy from a 75-year-old male system. This approach provided an optimal implant placement accuracy reducing surgical invasiveness.

Download Full-text

Immediate implant-retained prosthetic obturation after maxillectomy based on zygomatic implant placement by 3D-guided surgery: a cadaver study

International Journal of Implant Dentistry ◽

10.1186/s40729-021-00335-w ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

N. Vosselman ◽

H. H. Glas ◽

S. A. H. J. de Visscher ◽

J. Kraeima ◽

B. J. Merema ◽

...

Keyword(s):

Surgical Planning ◽

Immediate Loading ◽

Virtual Surgical Planning ◽

Implant Placement ◽

Ablative Surgery ◽

Zygomatic Implants ◽

Immediate Implant ◽

The Mean ◽

Obturator Prosthesis ◽

Zygomatic Implant

Abstract Background The aim of this study was to introduce a complete 3D workflow for immediate implant retained prosthetic rehabilitation following maxillectomy in cancer surgery. The workflow consists of a 3D virtual surgical planning for tumor resection, zygomatic implant placement, and for an implant-retained prosthetic-obturator to fit the planned outcome situation for immediate loading. Materials and methods In this study, 3D virtual surgical planning and resection of the maxilla, followed by guided placement of 10 zygomatic implants, using custom cutting and drill/placement-guides, was performed on 5 fresh frozen human cadavers. A preoperatively digitally designed and printed obturator prosthesis was placed and connected to the zygomatic implants. The accuracy of the implant positioning was obtained using 3D deviation analysis by merging the pre- and post-operative CT scan datasets. Results The preoperatively designed and manufactured obturator prostheses matched accurately the per-operative implant positions. All five obturators could be placed and fixated for immediate loading. The mean prosthetic point deviation on the cadavers was 1.03 ± 0.85 mm; the mean entry point deviation was 1.20 ± 0.62 mm; and the 3D angle deviation was 2.97 ± 1.44°. Conclusions It is possible to 3D plan and accurately execute the ablative surgery, placement of zygomatic implants, and immediate placement of an implant-retained obturator prosthesis with 3D virtual surgical planning.The next step is to apply the workflow in the operating room in patients planned for maxillectomy.

Download Full-text

Accuracy Evaluation of Computed Tomography–Derived Stereolithographic Surgical Guides in Zygomatic Implant Placement in Human Cadavers

Journal of Oral Implantology ◽

10.1563/aaid-joi-d-09-00074 ◽

2010 ◽

Vol 36 (5) ◽

pp. 345-355 ◽

Cited By ~ 25

Author(s):

Bruno R. Chrcanovic ◽

Davidson R. Oliveira ◽

Antônio L. Custódio

Keyword(s):

Computed Tomography ◽

Computer Aided Design ◽

Accuracy Evaluation ◽

Angular Deviation ◽

Implant Placement ◽

Surgical Guides ◽

Zygomatic Implants ◽

Computer Aided ◽

Human Cadavers ◽

Zygomatic Implant

Abstract Presurgical planning is essential to achieve esthetic and functional implants. For implant planning and placement, the association of computer-aided design (CAD) and computer-aided manufacturing (CAM) techniques furnishes some advantages regarding tridimensional determination of the patient's anatomy and fabrication of both anatomic models and surgical guides. The goal of this clinical study was to determine the angular deviations between planned and placed zygomatic implants using stereolithographic surgical guides in human cadavers. A total of 16 zygomatic implants were placed, 4 in each cadaver, with the use of stereolithographic (SLA) surgical guides generated by computed tomography (CT). A new CT scan was made after implant insertion. The angle between the long axis of the planned and actual implants was calculated. The mean angular deviation of the long axis between the planned and placed implants was 8.06 ± 6.40 (mean ± SD) for the anterior-posterior view, and 11.20 ± 9.75 (mean ± SD) for the caudal-cranial view. Use of the zygomatic implant, in the context of this protocol, should probably be reevaluated because some large deviations were noted. An implant insertion guiding system is needed because this last step is carried out manually. It is recommended that the sinus slot technique should be used together with the CT-based drilling guide to enhance final results. Further research to enhance the precision of zygomatic implant placement should be undertaken.

Download Full-text

Digital planning and guided surgery in oral rehabilitation

Clinical and Laboratorial Research in Dentistry ◽

10.11606/issn.2357-8041.clrd.2020.172078 ◽

2020 ◽

Author(s):

Larissa Braga dos Santos ◽

Adriano Relvas Barreira de Oliveira ◽

Mauro Lefrançois ◽

Marcos Venício Azevedo ◽

Pablo Sotelo ◽

...

Keyword(s):

Surgical Planning ◽

Three Dimensional ◽

Oral Rehabilitation ◽

Digital Workflow ◽

Surgical Guide ◽

Surgical Guides ◽

Digital Planning ◽

Cad Cam ◽

Correct Understanding ◽

Plaster Model

Digital planning of the prosthesis associated with surgical planning increased predictability, since surgical guides indicate the best place for implant installation, thus reducing the number of complications, and the CAD/CAM system provides predictability in the preparation of final restorations, according to the procedure previously planned. Our study reported a digital workflow used for the guided installation of two dental implants in regions 14 and 16, extraction of tooth 15 and installation of a fixed prothesis over implants. After anamnesis and clinical evaluation, intra- and extra-oral photographs of the patient were performed, molding the upper arch with polyvinylsiloxane (2-step putty/light-body technique) and requesting computed tomography. The plaster model obtained was sent to the laboratory and scanned. The generated file (STL) was used to create a diagnostic wax-up that was aligned to the tomography (in DICOM format), enabling the three-dimensional planning of the implants, which generated a partial printed surgical guide after approval of the dentist. After six months, the patient received the provisional fixed prosthesis printed in PMMA (polymethylmethacrylate) on an intermediate in PEEK (polyetheretherketone) aiming to condition an emergency profile to receive a definitive prosthesis two months later, with zirconia-milled infrastructure on a ti-base. The correct understanding of the operator about the steps of the digital workflow (diagnosis, prosthetic planning, surgical planning, guide preparation, temporary and final restorations) gives the operator improved predictability at the time of surgery as well as satisfactory aesthetic and functional result of definitive restorations.

Download Full-text

Rehabilitation of Maxillary Defect Using Zygomatic Implant Retained Obturator

Case Reports in Dentistry ◽

10.1155/2021/2391331 ◽

2021 ◽

Vol 2021 ◽

pp. 1-5

Author(s):

Mounika Ayinala ◽

Gautam Shetty

Keyword(s):

Hard Palate ◽

Odontogenic Myxoma ◽

Prosthetic Rehabilitation ◽

Implant Placement ◽

Heat Cure ◽

Maxillary Defect ◽

Zygomatic Implants ◽

And Function ◽

Zygomatic Implant

Tumors involving the hard palate, maxillary sinus, or nasal cavity require maxillectomy based on the extent of the lesion. Lack of these boundaries affects the speech, esthetics, and masticatory function. Prosthetic rehabilitation of these defects can be done utilizing zygomatic implants. This present case describes the use of a zygomatic implant to retain a maxillary obturator in a 22-year-old male patient following partial maxillectomy (Brown’s Class 2b) due to odontogenic myxoma. A surgical obturator was secured in position subsequent to the implant placement. Following the healing period, an interim obturator using heat cure acrylic was fabricated. Mechanical retention for the definitive obturator was obtained through the ball attachment suspended from the multiunit abutment of the zygomatic implant. The case was followed up closely for a year to evaluate the function of the prosthesis. The prosthetic rehabilitation not only promoted esthetics and function but also improved the patient’s quality of life.

Download Full-text

Neuronavigation as a Tool for Pre-Surgical Planning in Refractory Epilepsy Surgery

Neuroscience and Neurological Surgery ◽

10.31579/2578-8868/095 ◽

2019 ◽

Vol 5 (2) ◽

pp. 01-10

Author(s):

Carlos Valencia Calderón

Keyword(s):

Epilepsy Surgery ◽

Surgical Planning ◽

Refractory Epilepsy ◽

Surgical Experience ◽

Surgical Time ◽

Cross Sectional ◽

Guided Surgery ◽

Image Guided ◽

Eloquent Areas ◽

High Incidence

Summary Epilepsy is one of the most frequent chronic neurological pathologies, with high incidence and prevalence worldwide. A third of these patients are resistant to treatment, which is known as refractory epilepsy. Most of these patients suffer epilepsy secondary to epileptogenic lesions, where the surgery is the only treatment that could cure epilepsy. The goal of epilepsy surgery is to remove the epileptogenic area with preservation of eloquent areas, and here the surgical experience, the neuroimaging technology and the availability of image-guided surgery systems known as a neuronavigator plays a key role. Objectives: To demonstrate the usefulness of neuronavigation in pre-surgical planning and in the surgery of refractory epilepsy. Method: A cross-sectional and analytical descriptive study was conducted based on 47 surgeries performed (12 resective, 32 palliative and 3 diagnostic) in patients with refractory epilepsy and mean age of 9.93 years (SD 4.1). In 27 patients (57.44%) the neuronavigator was used. In the group of patients operated with neuronavigation, the surgical time decreased by 47.17 minutes (p = 0.022), the amount of bleeding by 111.41 milliliters (p = 0.011) and the days of hospitalization by 6.68 days (p = 0.005), compared with the group operated without neuronavigation. Complications in the neuronavigation group were 29.63% compared to 65% in the group operated without neuronavigation (p = 0.034). Conclusions: In our series, the use of the neuronavigator in the planning and development of the surgery had a significant impact by reducing the amount of bleeding lost, the surgical time, the days of hospitalization, and the post-surgical complications.

Download Full-text

Oral Rehabilitation with Zygomatic Implants in a Patient with Cleft Palate

Case Reports in Dentistry ◽

10.1155/2019/6591256 ◽

2019 ◽

Vol 2019 ◽

pp. 1-5 ◽

Cited By ~ 1

Author(s):

Guilherme José Pimentel Lopes de Oliveira ◽

Mariana Schaffer Brackmann ◽

Larissa Carvalho Trojan ◽

Paulo Domingos Ribeiro Júnior ◽

Luis Eduardo Marques Padovan

Keyword(s):

Cleft Palate ◽

Fibrous Tissue ◽

Oral Rehabilitation ◽

Atrophic Maxilla ◽

Zygomatic Implants ◽

Fixed Prosthesis ◽

Edentulous Patients ◽

The Right ◽

Zygomatic Implant

Edentulous patients with an atrophic maxilla associated with lip-palate fissures have unpredictable results after undergoing grafting procedures. In situations where the atrophic maxilla does not adequately allow reconstruction, the use of zygomatic implants has been indicated, and probably these implants can be indicated for the rehabilitation of patients with lip-palate fissures. This case report describes the oral rehabilitation treatment of a patient with a lip-palate cleft treated with zygomatic implants and implant-supported fixed prosthesis with two years of follow-up. A 65-year-old female patient had a lip-palate cleft and previously underwent surgery to close the cleft. The patient had a severely atrophic maxilla and had difficulty adapting to a removable total prosthesis. Due to the small amount of bone remaining and extensive fibrous tissue in the palate region, a rehabilitation with conventional implants associated with zygomatic implants was chosen. Two zygomatic implants and a conventional implant were placed on the right side, and a zygomatic implant and conventional implant were placed on the left side; these implants were later activated by a protocol-type prosthesis. The zygomatic implants provided an adequate aesthetic and functional outcome of the prosthesis in a patient with cleft palate.

Download Full-text

Computer-designed selective laser sintering surgical guide and immediate loading dental implants with definitive prosthesis in edentulous patient: A preliminary method

European Journal of Dentistry ◽

10.4103/1305-7456.126257 ◽

2014 ◽

Vol 08 (01) ◽

pp. 100-106 ◽

Cited By ~ 10

Author(s):

Giovanni Di Giacomo ◽

Jorge Silva ◽

Rodrigo Martines ◽

Sergio Ajzen

Keyword(s):

Dental Implants ◽

Computer Aided Design ◽

Manufacturing Systems ◽

Surgical Planning ◽

Selective Laser Sintering ◽

Laser Sintering ◽

Angular Deviation ◽

Surgical Guide ◽

Computer Aided

ABSTRACT Objective: The aim of this study was to analyze a preliminary method of immediately loading dental implants and a definitive prosthesis based on the computer-aided design/computer-aided manufacturing systems, after 2 years of clinical follow-up. Materials and Methods: The study comprised one patient in good general health with edentulous maxilla. Cone beam computer tomography (CBCT) was performed using a radiographic template. The surgical plan was made using the digital imaging and communications in medicine protocol with ImplantViewer (version 1.9, Anne Solutions, Sao Paulo, SP, Brazil), the surgical planning software. These data were used to produce a selective laser sintering surgical template. A maxilla prototype was used to guide the prosthesis technician in producing the prosthesis. Eight dental implants and a definitive prosthesis were installed on the same day. A post-operative CBCT image was fused with the image of the surgical planning to calculate the deviation between the planned and the placed implants positions. Patient was followed for 2 years. Results: On average, the match between the planned and placed angular deviation was within 6.0 ± 3.4° and the difference in coronal deviation was 0.7 ± 0.3 mm. At the end of the follow-up, neither the implant nor the prosthesis was lost. Conclusions: Considering the limited samples number, it was possible to install the dental implants and a definitive prosthesis on the same day with success.

Download Full-text

Computer-Aided Rehabilitation Supported by Zygomatic Implants: A Cohort Study Comparing Atrophic with Oncologic Patients after Five Years of Follow-Up

Journal of Clinical Medicine ◽

10.3390/jcm9103254 ◽

2020 ◽

Vol 9 (10) ◽

pp. 3254 ◽

Cited By ~ 1

Author(s):

Gerardo Pellegrino ◽

Francesco Basile ◽

Daniela Relics ◽

Agnese Ferri ◽

Francesco Grande ◽

...

Keyword(s):

Quality Of Life ◽

Clinical Success ◽

Clinical Success Rate ◽

Zygomatic Implants ◽

Oncologic Patients ◽

Computer Aided ◽

Prosthetic Complications ◽

Maxillary Atrophy

The aim of this study was to evaluate the survival and clinical success rate, complications, and patients’ quality of life after computer-aided rehabilitation supported by zygomatic implants in cases of severe maxillary atrophy (ten patients) and in bone defects in oncologic patients (ten patients). All patients underwent computer-aided planning and surgery. Seventy-three zygomatic implants were placed. The mean follow-up period was 39.9 months. Implant survival and clinical success rate, the effectiveness of planning the implant length, biological and prosthetic complications, and the quality of life were evaluated. The five-year implant survival rate for patients with maxillary atrophy and oncologic patients was 97.4% and 96.7%, respectively. The prosthetic survival rate was 100%. Two implant failures occurred in the first year. One implant failure was observed in each group. Minor biological and prosthetic complications occurred in both groups without significant differences. All complications were managed without affecting the treatment. The quality of life increased by 71.3% in the atrophic group and by 82.9% in the oncologic group. Zygomatic implant rehabilitation seems to be a reliable technique for patients with maxillary atrophy and for oncologic patients. The three-dimensional computer-aided approach allows the surgeon to plan the surgery and increase its predictability. Early prosthesis loading certainly allows for better functional outcomes.

Download Full-text

Fully Digital Workflow for Planning Static Guided Implant Surgery: A Prospective Accuracy Study

Journal of Clinical Medicine ◽

10.3390/jcm9040980 ◽

2020 ◽

Vol 9 (4) ◽

pp. 980 ◽

Cited By ~ 1

Author(s):

Chia-Cheng Lin ◽

Ching-Zong Wu ◽

Mao-Suan Huang ◽

Chiung-Fang Huang ◽

Hsin-Chung Cheng ◽

...

Keyword(s):

Fiducial Marker ◽

Surface Registration ◽

Digital Data ◽

Angular Deviation ◽

Digital Workflow ◽

Implant Surgery ◽

Surgical Guides ◽

Digital Planning ◽

Clinical Accuracy ◽

Edentulous Patients

The accuracy of static guided implant surgery (sGIS) using conventional planning workflow has been extensively examined; however, more information is required to justify the application of fully digital planning protocol. The purpose of this study was to investigate the clinical accuracy of sGIS with a fully digital planning workflow. Twenty-one partially edentulous patients were enrolled in this prospective study. Cone-beam computed tomography (CBCT) and intraoral scans were taken and superimposed by matching the dental surface images directly (surface registration protocol) or by matching fiducial markers on a stereolithographic (SLA) radiographic template fabricated from the digital data of the intraoral scan (fiducial marker registration protocol). Virtual implant treatment plans were then determined, and tooth-supported SLA surgical guides were fabricated according to the plans. Twenty-six implant surgeries were performed via the surgical guide by one surgeon. Pre- and post-operative CBCT images were superimposed, and the positional and angular deviations between placed and planned implants were measured with metrology software. A total of 43 fully guided implants were placed, in which 25 implants were planned with the surface registration protocol. Implants planned based on the surface registration protocol had a larger mean angular deviation than the fiducial marker registration protocol. No significant differences were found for any deviations of the examined variables. Within the limits of this study, we concluded that the clinical accuracy of the sGIS planned with a fully digital workflow was consistent with the conventional workflow for partially edentulous patients.

Download Full-text