Maxillary complete-arch implant-supported restoration: A digital scanning and maxillomandibular relationship workflow

Intraoral scanners are increasingly used as a replacement for conventional impressions, including the capturing of edentulous arches, although their use may be clinically challenging. This technique article describes the fabrication and use of a custom scanning device to scaffold an intraoral complete-arch scan of at least 6 implant scan bodies in the edentulous maxilla while simultaneously capturing the maxillomandibular relationship for the purpose of establishing a digital workflow to fabricate a maxillary complete-arch implant-supported prosthesis.     

Maxillary and mandibular complete-arch implant rehabilitation using a complete digital workflow: A case report

This article summarizes the clinical steps involved in maxillary and mandibular complete-arch implant rehabilitation using a complete digital workflow. The maxillary arch was recorded using the double digital scan technique, and the mandibular arch using the triple digital scan technique. The digital protocol used in this case report allowed the recording of implant positions via scan bodies, soft tissues, and, most importantly, the interocclusal relationship in the same visit. A new technique for mandibular digital scan was described that uses soft tissue landmarks by creating windows in the patient's provisional prostheses to superimpose the three digital scans and consequently fabricate and verify the maxillary and mandibular prototype prostheses and definitive complete-arch zirconia prostheses.     

Complete-arch maxillary rehabilitation using a custom-designed and manufactured titanium framework: a clinical report

Fabrication of a passive framework when restoring multiple implants in an edentulous maxilla may be an important requisite for long-term implant survival. The development of computer-aided design and manufacturing techniques for fabricating custom 1-piece titanium frameworks can simplify that challenge. This article reports on a treatment in which a custom-milled titanium complete-arch maxillary framework was used to restore a compromised maxillary arch. A 4-year follow-up demonstrated a steady state of bone and no prosthodontic complications.     

Designing a complete-arch digital trial tooth arrangement for completely edentulous patients by using an open-source CAD software program: A dental technique

A method for creating a complete-arch digital trial tooth arrangement for completely edentulous patients is described. The technique demonstrates an effective way to reproduce the dental and gingival anatomies by using a free 3D modeling software program. This cost-effective, time-saving, and versatile method allows dental professionals to digitally plan challenging treatments for completely edentulous patients. The technique can also be used to fabricate diagnostic prostheses and implant-supported interim prostheses.     

*"All-on-4"种植即刻修复技术的临床应用研究

目的 评价应用"All-on-4"种植即刻修复技术对牙列缺失患者进行种植即刻修复的临床效果,探讨其技术要点及临床意义.方法 2008年4月至2009年10月共29例患者(男15例,女14例)接受了"All-on-4"种植即刻修复.29例(上颌牙列缺失8例,下颌牙列缺失15例,全口牙列缺失6例)共植入140枚种植体,在种植体植入当天完成即刻修复,一共完成35件"All-on-4"即刻义齿.即刻修复后观察种植体边缘骨吸收情况、修复体功能状况、患者满意度,追踪种植体的存留率.患者平均追踪10个月(6～24个月).结果 140枚种植体中,8枚于植入后6～8周脱落;其余132枚种植体至最后一次复查临床稳定,种植体存留率94.3%;即刻修复义齿的存留率94%(33/35);边缘骨吸收程度为(0.8±0.4)mm.结论 "All-on-4"种植即刻修复技术应用于牙列缺失患者近期效果好,患者满意度高.远期效果需要进一步观察.     

Accuracy analysis of complete-arch digital scans in edentulous arches when using an auxiliary geometric device

Statement of problem

Obtaining reliable digital scans of edentulous patients is challenging because of the absence of anatomic landmarks/geometric variations along the dental arch. Whether adding an auxiliary geometric device (AGD) will improve scanning is unclear.

Use of transitional implants to support a surgical guide: enhancing the accuracy of implant placement

Surgical guides for edentulous patients often lack the stability desired for accurate implant placement. The difficulty is emphasized in the edentulous mandible when implant-supported metal-ceramic restorations, which require precise placement of implants, are planned. A technique is presented for the fabrication of a surgical and radiographic template, supported by transitional implants, that guides the placement of conventional implants. This template can enhance placement accuracy in an efficient way to achieve predictable, esthetic results.     

Cast-free digital workflow for implant-supported rehabilitation in a completely edentulous patient: A clinical report

Digitalization of edentulous areas restored with dental implants is still considered a demanding procedure, mainly because of the lack of fixed reference landmarks, together with an increased interimplant distance. To overcome such limitations, an auxiliary device is introduced with the 3-fold purpose of stretching the soft tissues with a fixed object connected to the scan bodies, creating areas with nonhomogeneous architectures between the implants, and shortening the interimplant distance with the interposition of solid geometric figures. The rationale was to increase the accuracy of digital scans in a cast-free digital implant workflow.     

A Technique to Stabilize Record Bases for Gothic Arch Tracings in Patients with Implant-Retained Complete Dentures

Clinicians have long expressed concern about the accuracy of the Gothic arch tracing for recording centric relation in edentulous patients. With the use of dental implants to assist in retaining complete dentures, the problem of inaccurate recordings, made for patients without natural teeth, can be significantly reduced. This article presents a technique that uses healing abutments to stabilize the record bases so that an accurate Gothic arch tracing can be made.     

Intraoperative computerized navigation for flapless implant surgery and immediate loading in the edentulous mandible

Computerized navigation surgery has evolved to facilitate minimally invasive procedures, the gold standard of surgery today. While flapless implant surgery may be clinically beneficial, it has generally been perceived as a blind procedure limited to straightforward cases that do not pose a risk of cortical plate perforation. The objective of this report is to describe a protocol for flapless implant placement in a completely edentulous mandible using computerized navigation surgery. The Image Guided Implantology system (IGI, DenX Advanced Dental Systems) is described. The IGI system provides real-time imaging of the dental drill and transforms flapless implant surgery into a fully monitored procedure. The highly accurate intraoperative navigation enables precise transfer of the detailed presurgical implant plan to the patient. This is particularly valuable in edentulous jaws lacking any indication of the dental arch. The accurate positioning of the implants, based on the presurgical digital plan, allows fabrication of a provisional fixed prosthesis before the implant surgery for immediate postoperative loading. This innovative protocol can enhance prosthodontic-driven placement of implants in a fully monitored flapless surgery.     

Fabricating Low-Fusing Metal Casts for More Accurate Implant Prosthodontics

An important factor that affects the clinical success of dental implants is the way stresses are transferred to the bone via the implant framework and fixture. An ill-fitting implant framework will contribute to these stresses and may result in catastrophic failure of the prosthesis or one of the components and/or fixtures, in addition to possible alveolar bone loss. Many factors may contribute to the difficulty of achieving a passive fit on a complete-arch implant framework. A technique for producing an accurate master cast by using a low-fusing metal is described. The low-fusing metal is dimensionally more accurate than conventional gypsum products. The technique does not require a significant change from conventional chairside and laboratory procedures for complete-arch master cast impressions, and should result in a more passively fitting framework.     

Orthodontic Treatment and Implant‐Prosthetic Rehabilitation of a Partially Edentulous Patient

This article describes the treatment of a 61‐year‐old man who had a completely edentulous maxillary arch and partially edentulous mandibular arch. The patient was orthodontically treated to correct an anterior crossbite by distalization of the mandibular teeth using a removable prosthesis serving as an anchorage unit. Subsequently, the patient received two zygomatic implants, five conventional implants in the maxillary arch, and six conventional implants in the mandibular arch. By the end of treatment, the convexity of the facial profile improved, and esthetic and functional occlusion was established.     

Five-year results with fixed complete-arch mandibular prostheses supported by 4 implants

This study examined whether it is possible to restore an edentulous mandible with a complete-arch fixed prosthesis retained by only 4 implants without decreasing the survival rate. One hundred nineteen patients received complete-arch mandibular prostheses retained by 4 implants. Most patients were followed for 3 years or more. All patients followed a routine protocol, including annual check-ups and regular radiographic examinations. Twenty-one patients dropped out. Radiographic measurements used the threads of the implants as a basis for comparison. No indication was found that the number of supporting implants could have influenced the observed frequency of technical and surgical complications. Three implants were lost, 2 after 1 year and 1 after 5 years. A statistically significant difference in bone loss between the mesial and distal implants was found. The number of fractured resin teeth in mandibular prostheses was higher when patients had an implant-supported prosthesis in the maxilla. The present study revealed an implant survival rate of 98.6% after 5 years. Therefore, it was concluded that there may not be a need for more than 4 implants to support a fixed mandibular prosthesis, when implants at least 10 mm long can be used.     

Fully digital fabrication of an occlusal device using an intraoral scanner and 3D printing: A dental technique

This dental technique describes a fully digital method for fabricating occlusal devices using a complete-arch intraoral scan and 3D printing. The maxillary and mandibular arches of a healthy, fully dentate volunteer were digitized using an intraoral scanner. A second scan and modified recording of the centric relation enabled a virtual arrangement of the maxillary and mandibular arches, both in centric relation and in the desired vertical dimension of occlusion. An occlusal device was subsequently designed virtually and fabricated from a light-polymerizing acrylic resin using a 3D printer. The occlusal device was tested for fit, occlusion, and patient-friendly handling. As only minor occlusal corrections were required, the fully digital procedure described is suitable for the fabrication of occlusal devices.     

CAD-CAM–fabricated interim fixed complete-arch implant-supported restorations based on the existing dentition

An interim restoration is often used to assess the patient's functional and esthetic needs for implant-supported complete-arch fixed prostheses. A digital protocol for accurately transferring information from the existing dentition to the interim restoration is required. The purpose of this clinical report was to describe a digital workflow to fabricate an interim fixed restoration by using the vertical dimension of occlusion and occlusal relationship from the original dentition to provide an accurate, efficient, and predictable computer-aided design and computer-aided manufacturing (CAD-CAM) interim complete-arch implant-supported restoration.     

Analysis of 164 titanium oxide-surface implants in completely edentulous arches for fixed prosthesis anchorage using the pterygomaxillary region

PURPOSE: The purpose of the article was to evaluate the survival rates of TiUnite implants and then compare them to a previous similar study of machined-surface implants. MATERIALS AND METHODS: This report presents the results of 82 consecutive patients treated since the introduction of Nobel Biocare's TiUnite surface. The patients were treated with complete-arch restorations using bilateral pterygomaxillary implants in edentulous maxillae. A total of 840 implants were placed in immediate extraction or healed sites, with a mean of 10 implants placed per patient. RESULTS: In all, 826 of the 840 implants osseointegrated, for a cumulative survival rate (CSR) of 98.3%. One hundred fifty-eight of 164 pterygomaxillary implants successfully osseointegrated, yielding a 96.3% survival rate. DISCUSSION AND CONCLUSION: The results of this complete-arch maxillary prospective study suggest that Br?nemark System TiUnite implants are more predicable than implants with a machined surface. Compared to a similar 1999 study in which the survival rate for machined-surface implants was 92.1%, the present study had a significantly higher survival rate of 98.6% with the TiUnite surface (P < .001). In the pterygomaxillary region, there was an increase of 8% with the TiUnite surface as opposed to the machined surface (P < .001). In addition, 62% of the implants in the present study were immediately loaded, compared to 0% in the machined-surface implant study. The titanium oxide surface appears to assist the healing response of the bone-implant interface.     

A Novel Approach for Converting a Mandibular Complete Denture to a Fixed Interim,Screw‐Retained Implant Prostheses: A Case Report

For most of the last century, conventional complete dentures have been the standard of care and the most common treatment for edentulous patients. Technological advancements in fabrication techniques may significantly reduce the number of office visits required to fabricate complete dentures. Immediate occlusal loading with mandibular full arch prostheses has been extensively researched and is now one of the standards of care for edentulous patients. A clinical technique for converting a mandibular immediate complete denture to an interim full arch, screw‐retained fixed prosthesis with novel implant restorative components for immediate loading on four implants is described.     

A modified indirect working die technique for fabricating provisional restorations for multiple teeth.

The "modified" indirect working die technique is introduced. The technique expands the capabilities of the indirect working die technique, which features flexible removable dies for fabricating provisional restorations. The modified technique is distinguished by its potential for restoring multiple teeth, up to and including the complete arch, by utilizing a complete-arch impression tray to which a simple modification is made. It is an accurate, timesaving, and laborsaving method for fabricating provisional restorations.     

Early load mandibular hybrid prosthesis using the Ohio State University acrylic frame requiring no final impression

Background:  Although immediate/early loading protocols for dental implants have presented encouraging outcomes, immediate loading procedures may cause discomfort to the patient and may increase the possibility of damage to the surgical site during the impression procedures. The aim of this study was to describe an alternative technique to fabricate a mandibular hybrid prosthesis in three or four days without making any final impression and to evaluate the outcomes of this technique.
Methods:  Seven patients aged 41 to 71 years (mean age, 58 ± 11) were considered for this study. Each patient received five implants for the reconstruction of the edentulous mandible. These implants were placed in the anterior region of an edentulous mandible and restored with a final mandibular hybrid prosthesis in four days using the Ohio State University (OSU) acrylic frame requiring no final impression procedure. The patients were followed up to 19 months after implant placement.
Results:  No implants were lost, no technical complications were observed and only minor marginal bone loss was noted after an average 15 months.
Conclusions:  This clinical study shows that the OSU acrylic frame, which can easily be customized and accommodates variability in arch form, may be an alternative method to restore any edentulous mandible with an early load mandibular hybrid prosthesis.     

Two-step pick-up impression procedure for implant-retained overdentures

This article describes a procedure that permits careful border correction and impression fabrication of an edentulous arch, followed by pick-up of implant impression copings. The resultant master cast is accurate in terms of soft tissue detail, position of implant components, and relationship between soft tissue and implants.