The International Journal of Oral & Maxillofacial Implants, 1/2020
Online OnlyDOI: 10.11607/jomi.7668, PubMed-ID: 31923302Seiten: e15-e20, Sprache: Englisch
This case report describes a digital workflow for a computer-aided design/computer-assisted manufacturing (CAD/CAM) healing abutment used in immediate implant placement in the esthetic zone. The design of the healing abutment was based on the existing tooth anatomy in order to provide anatomical support to the gingival tissues and to preserve the gingival contours of the natural tooth. This approach enhances the esthetic outcome of the definitive implant restoration. The surgical procedure including the guided bone regeneration is simplified, postoperative morbidity is reduced, and excessive occlusal loading during healing is limited.
Schlagwörter: CAD/CAM healing abutment, computer-guided surgery, immediate implant placement
QZ - Quintessenz Zahntechnik, 9/2019
Seiten: 1114-1120, Sprache: Deutsch
In der dargestellten In-vitro-Studie wurde die Genauigkeit von Implantatschablonen untersucht, die mit drei unterschiedlichen 3-D-Druckverfahren hergestellt wurden. Dabei wurden jeweils zehn identische Implantatschablonen mit vier 3-D-Druckern (Hersteller und Modell zweier Drucker identisch) gedruckt. Alle Implantatschablonen wurden mit einem Referenz-Scanner gescannt und anschließend in die Darstellungssoftware importiert. Die Software berechnete über eine Best-fit-Überlagerung automatisch die dreidimensionalen Abweichungen aller Punkte. Es zeigte sich, dass alle getesteten Drucker ein hohes Maß an Genauigkeit erreichten, was den versuchsweisen Einsatz kostengünstiger Drucker bei der klinischen Herstellung von Implantatschablonen rechtfertigt.
Schlagwörter: additive Fertigung, 3-D-Druck, Stereolithografie, Genauigkeit, Implantatschablone
The International Journal of Prosthodontics, 1/2019
DOI: 10.11607/ijp.5975, PubMed-ID: 30677120Seiten: 97-100, Sprache: Englisch
Purpose: This in vitro study aimed to evaluate the accuracy of surgical templates fabricated using three different 3D printing technologies.
Materials and Methods: Ten identical surgical templates were printed using four 3D printers (two of an identical make and model). Each of the surgical templates was scanned by a reference scanner and then imported into the inspection software. Inspection software utilized a best-fit alignment to automatically calculate the 3D variation at all points.
Results: Statistically significant differences were found among the three groups (χ2 = 12.880, P = .0016). Mean 3D deviation was also significantly different between the two printers of an identical make and model (χ2 = 8.251, P = .0041).
Conclusion: All of the tested printers had a high level of accuracy in the fabrication of surgical templates, which would justify the trial of cost-effective printers for clinical fabrication of surgical implant templates.
The International Journal of Oral & Maxillofacial Implants, 4/2017
DOI: 10.11607/jomi.5546, PubMed-ID: 28708910Seiten: 801-806, Sprache: Englisch
Purpose: The purpose of this study was to examine the anatomy of the mandibular posterior region to develop an anatomical categorization for implant-prosthodontic planning.
Materials and Methods: Using cone beam computed tomography scans, 313 cross-sectional views of edentulous posterior mandibular sites were evaluated with respect to the anatomical ridge morphology. Virtual implant planning was performed, and the need for bone grafting was assessed. The level of complexity for planning implants in those positions was assessed. Sites were classified as straightforward, advanced, or complex sites based on the need for bone grafting.
Results: Five well-defined cross-sectional configurations were observed: straight (53.6%), oblique (26.2%), s-shape (7.4%), hourglass shape (1.9%), and basal bone (10.8%). There was a statistically significant association between the ridge shape and the feasibility of placing an implant with or without bone grafting; the straight and oblique ridge shapes were more likely to be associated with a favorable anatomy for implant placement.
Conclusion: The ridge shape significantly influenced the ease or difficulty of placing an implant. The s-shape, hourglass, and basal bone posterior mandibular cross-sectional shapes were associated with a higher degree of difficulty.
Schlagwörter: dental implants, mandibular classification, posterior edentulous mandible, ridge morphology, virtual implant planning
The International Journal of Oral & Maxillofacial Implants, 7/2016
Supplement Online OnlySeiten: 192-197, Sprache: Englisch
Purpose: This review was conducted to provide information to support the establishment of clinical guidelines for the treatment of maxillary edentulism using implant-supported fixed dental prostheses.
Materials and Methods: Initial efforts were directed toward a systematic review with a defined PICO question: "For maxillary edentulous patients with dental implants treated using a fixed prosthesis, what is the impact of prosthesis design on prosthesis survival and complications?" Following a title search of more than 3,000 titles identified by electronic search of PubMed, 180 articles were identified that addressed the clinical evaluation of maxillary dental implant prostheses. The broad methodologic heterogeneity and clinical variation among reports precluded this approach for a systematic review. The information was extracted using a standardized extraction table by two pairs of investigators, and the reported outcomes were then summarized according to reported outcomes for implant prostheses supported by four, six, or eight implants using unitary or segmented prostheses.
Results: This review indicated that high prosthetic survival is observed using all approaches. The advantages of using fewer implants and a unitary prosthesis are revealed in the surgical phases, and complications commonly involve the fracture or detachment of acrylic teeth and reduced access for proper oral hygiene and related biologic complications. Using six implants typically involved grafting of posterior regions with advantages of reduced cantilevers and redundancy of implant support. Reduced prosthesis survival in these cases was associated with poor implant distribution. Segmented prostheses supported by six or more implants offered greater prosthetic survival, perhaps due to posterior implant placement. Advantages of a segmented prosthesis included pragmatic issues of accommodating divergent implants, attaining passive fit, combining prosthetic materials, and relative simplicity of repair.
Conclusion: The existing literature demonstrated that maxillary edentulism may be treated successfully using alternative approaches involving four, six, or more implants. The procedural diagnostics, treatment, and maintenance for these different approaches all require advanced knowledge and careful communication among the therapeutic team. The prosthetic therapeutic success requires maintenance, repair, and possible multiple replacements within the patient's lifetime.
The International Journal of Oral & Maxillofacial Implants, 2/2015
DOI: 10.11607/jomi.3817, PubMed-ID: 25830401Seiten: 403-410, Sprache: Englisch
Purpose: The objectives of this case series are to describe a novel clinical approach to treat completely edentulous patients and determine its viability. Computer-guided implant planning was used to create a screwretained surgical template (ST) supported by transitional implants and a fixed screw-retained provisional prosthesis supported by the transitional implants at the time of definitive implant placement.
Materials and Methods: Five patients with at least one edentulous arch were treated. After the diagnostic tooth setup was performed, a duplicate with radiopaque acrylic resin was fabricated to serve as a surgical template (ST) for the placement of screw-form transitional implants and a radiographic guide (RG). Four transitional implants were strategically placed through the guide where they would not interfere with the future definitive implants. The transitional implants were used to support the RG during computed tomographic scanning. Subsequently, the RG was converted into a second ST based on three-dimensional virtual planning. Eight implants were placed by the computer-guided system, and an immediate prefabricated fixed provisional was connected to the transitional implants.
Results: All the implants included in the study achieved primary stability and osseointegrated successfully. For 4 months, the transitional implants served successfully as abutments for the provisional prosthesis.
Conclusion: This innovative clinical approach overcomes the limitations of a mucosa/ bone-supported ST by offering fixed, reproducible support for the RG and ST by means of transitional implants. The delivery of a prefabricated screw-retained provisional on transitional implants allows for passive healing and minimum chairside adjustments.
Schlagwörter: computer-guided surgery, dental implants, full-arch implant rehabilitation, full-arch fixed provisionalization, transitional implant
The International Journal of Oral & Maxillofacial Implants, 7/2014
SupplementDOI: 10.11607/jomi.2014suppl.g4.2, PubMed-ID: 24660201Seiten: 239-255, Sprache: Englisch
Purpose: The aim of this study was to systematically review the evidence for immediate implant loading in partially edentulous patients with extended edentulous sites and evaluate potential treatment modifiers.
Materials and Methods: An electronic search was performed in Medline, Embase, and Central to identify studies investigating the outcome of implants subjected to immediate loading (IL) (less than 1 week), early loading (EL) (1 week to 2 months), or conventional loading (CL) (more than 2 months) with implant-supported fixed dental prostheses (IFDPs) in partially edentulous patients with extended edentulous sites, ie, at least two adjacent teeth are missing. Only human studies with at least 10 cases and a minimum follow-up time of 12 months, reporting on solid-screw-type implants with rough surfaces and a diameter of at least 3 mm, were included. Weighted means of implant survival rates and risk ratios for implant survival at 1 year using meta-analytic tools were calculated to perform the following comparisons: IL vs EL, IL vs CL, and IL in the maxilla vs mandible. Noncomparative studies reporting on IL and EL protocols were summarized through descriptive methods.
Results: The search provided 3,872 titles, 837 abstracts, and 444 full-text articles. A total of 24 publications that comprised six comparative studies (five randomized controlled trials, one nonrandomized controlled trial) and 18 noncomparative studies were included for analysis. The comparison of weighted mean survival rates revealed no statistically significant difference between IL (97.9%) and EL (97.8%, P = .9405), and between IL (100%) and CL (99.3%, P = .3280). Meta-analysis showed no statistically significant difference in implant survival at 1 year between IL and EL (RR 0.90; 95% CI 0.30, 2.70; P = .502). A meta-analysis comparing IL and CL could not be performed due to the low number of failures. No statistically significant difference was found for IL implants placed in the maxilla vs the mandible (RR 1.55; 95% CI 0.49, 4.84; P > .05). Due to the small number of IL implants placed in the anterior, a comparison between implant survival in anterior vs posterior zones was not performed. Treatment modifiers were bone quality, primary stability, insertion torque, ISQ values, implant length, the need for substantial bone augmentation, the timing of implant placement, and the presence of parafunctional and smoking habits.
Conclusions: IL presents similar implant survival rates as EL or CL for partially edentulous patients with extended edentulous sites in the posterior zone, as long as strict inclusion/exclusion criteria are followed. There is a lack of evidence for IL of multiple implants in the anterior zone of partially edentulous patients. Preliminary evidence suggests that IL may be equally successful in either the maxilla or mandible. Further research is needed before IL in partially edentulous patients with extended edentulous sites can be recommended in everyday practice.
Schlagwörter: conventional loading, dental implants, early loading, fixed dental prostheses, immediate loading, meta-analysis, partial edentulism, systematic review
The International Journal of Oral & Maxillofacial Implants, 7/2014
SupplementDOI: 10.11607/jomi.2013.g4, PubMed-ID: 24660204Seiten: 287-290, Sprache: Englisch
The International Journal of Oral & Maxillofacial Implants, 4/2014
DOI: 10.11607/jomi.3625, PubMed-ID: 25032763Seiten: 836-845, Sprache: Englisch
Purpose: To compare the accuracy of digital and conventional impression techniques for partially and completely edentulous patients and to determine the effect of different variables on the accuracy outcomes.
Materials and Methods: An electronic and manual search was conducted to identify studies reporting on the accuracy of implant impressions. Pooled data were descriptively analyzed. Factors affecting the accuracy were identified, and their impact on accuracy outcomes was assessed.
Results: The 76 studies that fulfilled the inclusion criteria featured 4 clinical studies and 72 in vitro studies. Studies were grouped according to edentulism; 41 reported on completely edentulous and 35 on partially edentulous patients. For completely edentulous patients, most in vitro studies and all three clinical studies demonstrated better accuracy with the splinted vs the nonsplinted technique (15 studies, splint; 1, nonsplint; 9, no difference). One clinical study and half of the in vitro studies reported better accuracy with the open-tray vs the closed-tray technique (10 studies, open-tray; 1, closed-tray; 10, no difference). For partially edentulous patients, one clinical study and most in vitro studies showed better accuracy with the splinted vs the nonsplinted technique (8 studies, splint; 2, nonsplint; 3, no difference). The majority of in vitro studies showed better accuracy with the open-tray vs the closed-tray technique (10 studies, open-tray; 1, closed-tray; 7, no difference), but the only clinical study reported no difference.
Conclusion: The splinted impression technique is more accurate for both partially and completely edentulous patients. The open-tray technique is more accurate than the closed-tray for completely edentulous patients, but for partially edentulous patients there seems to be no difference. The impression material (polyether or polyvinylsiloxane) has no effect on the accuracy. The implant angulation affects the accuracy of implant impressions, while there are insufficient studies for the effect of implant connection type. Further accuracy studies are needed regarding digital implant impressions.
Schlagwörter: accuracy, dental implants, digital impressions, edentulous, implant impressions, impression techniques
The International Journal of Prosthodontics, 4/2014
DOI: 10.11607/ijp.3791, PubMed-ID: 25010874Seiten: 320-327, Sprache: Englisch
Purpose: This study aimed to develop a classification of edentulous jaws for use as a diagnostic tool during implant-prosthodontic treatment planning.
Materials and Methods: The morphology of 200 fully edentulous alveolar ridges (100 maxillae, 100 mandibles) was assessed with cone beam computed tomography. Generic implants (length: 8 mm; diameter: 4.1 mm) were used. To develop the classification system, the feasibility of virtually placing the implants without vertical ridge augmentation was considered. Potential implant sites were evaluated in terms of ridge width and described as either type A (no horizontal augmentation required) or type B (horizontal augmentation required). A descriptive statistical analysis of subjects' age, sex, and arch classification was performed.
Results: In total, 880 implants were virtually planned. Based on alveolar ridge height, four arch patterns were identified (C1 to C4), providing a basis for prosthodontic planning with either removable or fixed implant-supported restorations. The frequencies of each category were as follows: C3 (n = 62, 62%), C4 (n = 16, 16%), C2 (n = 12, 12%), and C1 (n = 10, 10%) for the maxilla and C3 (n = 36, 36%), C4 (n = 31, 31%), C1 (n = 24, 24%), and C2 (n = 9, 9%) for the mandible.
Conclusion: The proposed classification of the edentulous arch represents a useful tool for communication between clinicians when planning implantsupported rehabilitations.