Technique for cementing screwmentable implant crowns to prevent misalignment.

The purpose of this article is to describe a technique to accurately cement implant crowns on an abutment extraorally and prevent misalignment that might change the desired position of the crown on the abutment when delivered. An implant-retained crown was tried-in and occlusal and interproximal contacts were adjusted for delivery. The cementation verification aid was fabricated using a polyvinylsiloxane bite registration material (Blu Mousse) to cement the crown onto the abutment extraorally to ensure proper alignment of the crown on the abutment. Cementation of the prosthesis occurred with no adjustments required to the interproximal or occlusal contacts during final delivery. This article provides a technique that aims to increase accuracy in the placement of the crown on the abutment when cementing screwmentable crowns.

Expedited Provisionalization of a Missing Crown: A Case Report.

Provisional restorations are required in fixed prosthodontics to protect a prepared tooth until a definitive restoration can be delivered. A patient sought treatment at a prosthodontics practice to replace a missing provisional crown until definitive treatment could be performed once the patient returned from a field exercise. This case report describes a novel way to provide a provisional restoration when other techniques are not feasible, which can be utilized in the clinic or in an austere environment.

Printed abutment model to limit residual cement: A dental technique.

Preventing retained cement around implant-retained crowns is crucial for the long-term health and success of the implant. Residual subgingival cement is strongly associated with peri-mucositis and can lead to peri-implantitis. This clinical technique utilizes a 3D printed model of a custom abutment to seat the implant crown on before cementing intra-orally to extrude excess cement. The technique aims to limit the amount of retained cement at the crown-abutment margin and also takes into consideration the cement space already designed into the crown-abutment complex.

Gradated silicone shade guide utilized for shade matching extraoral prostheses.

Shade matching of extraoral prostheses is completed by mixing pigments and rayon flocking into medical-grade silicone and using a carrier to evaluate the color match. This process does not account for how material thickness affects the appearance of the silicone. This clinical case report discusses an innovative way to match the patient's skin tone using a digitally designed gradated silicone carrier and how this device allows for the assessment of shade from the thin marginal edge to 5 mm thickness.

Restoration of a nonideally placed anterior implant: A clinical report.

This article describes a restorative solution for implants placed at an insufficient depth and in a patient with limited interarch space, making the esthetics, emergence profile, and retention of a cemented restoration problematic. These challenges were overcome by adhesively bonding a pressed lithium disilicate veneer to a custom cast metal abutment veneered with a thin layer of feldspathic porcelain. The ceramic veneer with the attached core engaged a facially located screw-access channel, which increased retention and resistance form and facilitated seating of the veneer. Adhesive bonding via the application of a thin layer of feldspathic porcelain on the custom dental implant abutment was also used to overcome the lack of resistance form with a veneer preparation.

Human Gingival Epithelial Growth In Vitro on a Polymer-Infiltrated Ceramic Network Restorative Material.

PURPOSE: To investigate the growth of primary human gingival epithelial (HGE) cells on polymer-infiltrated ceramic network (PICN) material (Vita Enamic) with different surface roughnesses. MATERIALS AND METHODS: PICN material specimens were polished with either silica carbide paper (grit-polished) or the manufacturer's polishing wheels (wheel-polished), and the surface roughness (Ra ) measured. HGE cells were seeded and grown for 1, 3, or 6 days. Growth on tissue culture plastic was used as a control. Non-linear regression analysis was used to examine the effect of surface roughness on cell growth. RESULTS: HGE cell growth on tissue culture plastic fitted an exponential growth model over the 6-day experimental period (R2 = 0.966). Through day 6, cell density on PICN decreased with increasing surface roughness, with a fit to an exponential decay model (R2 = 0.666). A threshold Ra value of 0.254 µm (95% CI 0.177-0.332) was determined as an upper limit for exponential growth. Cell growth was greatest on the group of specimens with Ra value below 0.127µm. Specimens polished by the manufacturer's method produced surface roughness of 0.118 µm and below. CONCLUSIONS: PICN material polished to a smooth surface (Ra < 0.254 µm) resulted in exponential growth of HGE cell growth compared to rough surfaces. Polishing PICN material as smooth as possible (below a Ra of 0.127 µm) was found to maximize epithelial cell growth on the PICN material surface. The manufacturer's polishing method achieved a sufficiently smooth surface. These results are contrary to previous research regarding surface roughness of transgingival implant restoration components. The study results suggest that smoother restorative material surfaces could improve peri-implant soft tissue health.

Total Auricular Rehabilitation: Combined Cosmetic and Functional Lateral Temporal Bone Reconstruction.

OBJECTIVE: The aim of the study was to describe 3 cases of total auricular rehabilitation, including the novel use of iliac crest bone grafts to support bone-anchored auricular prostheses. STUDY DESIGN: This study is a retrospective case series from a single institution. RESULTS: Three cases with large lateral temporal bone and soft tissue defects were successfully treated with total auricular rehabilitation. Rehabilitation included the following: soft tissue coverage with an anterolateral thigh microvascular free flap, iliac crest-free bone graft with staged placement of a bone-anchored auricular prosthesis into the bone graft, and audiologic rehabilitation with a bone-anchored hearing aid (BAHA). All of the cases with grafts and flaps survived and were without significant donor site morbidity. Bone-anchored hearing aid abutment skin overgrowth was seen in 2 cases and was revised under local anesthesia. All of the patients had expected functional recovery on postoperative audiologic testing. Each patient continues to consistently wear his/her auricular prosthesis and BAHA during 3 years of follow-up. CONCLUSIONS: Total auricular rehabilitation is a complex task involving reconstruction of extensive soft tissue defects, bony defects, and the hearing apparatus. Acceptable cosmetic and functional outcomes and high patient satisfaction is possible in committed patients.

Digital image capture and rapid prototyping of the maxillofacial defect.

In order to restore an extraoral maxillofacial defect, a moulage impression is commonly made with traditional impression materials. This technique has some disadvantages, including distortion of the site due to the weight of the impression material, changes in tissue location with modifications of the patient position, and the length of time and discomfort for the patient due to the impression procedure and materials used. The use of the commercially available 3dMDface™ System creates 3D images of soft tissues to form an anatomically accurate 3D surface image. Rapid prototyping converts the virtual designs from the 3dMDface™ System into a physical model by converting the data to a ZPrint (ZPR) CAD format file and a stereolithography (STL) file. The data, in conjunction with a Zprinter(®) 450 or a Stereolithography Apparatus (SLA), can be used to fabricate a model for prosthesis fabrication, without the disadvantages of the standard moulage technique. This article reviews this technique and how it can be applied to maxillofacial prosthetics.