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Design concept to facilitate the positioning of a custom abutment on an implant
With the development of computer-aided design and computer-aided manufacturing (CAD-CAM) technology, implant abutments have been fabricated with nearly unlimited design options.1,2 When an implant indexing device has not been fabricated or is not available, additional chair time for placing a custom abutment on a hexagonal connection implant is needed, especially for multiple implant restorations, as the abutment can be positioned in 6 different orientations.3,4 This article describes a design concept for fabricating a custom abutment with a mark.Chairside fabrication of a tooth reduction guide to ensure adequate occlusal clearance
Adequate tooth preparation is essential for the long-term success of a crown.1,2 Occlusal reduction must be conservative of tooth structure but provide adequate space for the restorative material.1,2 Insufficient occlusal reduction, especially on the lingual surface of molars, may occur because of limited access and visibility.3Fabricating an altered cast to facilitate intraoral processing of the LOCATOR attachment
The LOCATOR attachment (Zest Anchors LLC) has been widely used for implant-retained overdentures (IODs),1,2 with several techniques for incorporating the attachment into the IOD proposed.3-6 When the indirect method is used, a strong bond between the matrix and acrylic resin can be achieved, and staining or porosities on the intaglio surface of the IOD are prevented.3 However, the method requires additional laboratory procedures and expense, LOCATOR impression posts (Zest Anchors LLC) and the LOCATOR analog (Zest Anchors LLC) are needed, and distortion during denture processing may occur.An alternative topical anesthesia technique for prosthetic implant procedures
Time-dependent change of the peri-implant mucosal profile occurs after the removal of healing abutments.1 Nissan et al1 reported that the peri-implant mucosa shrinkage was 31% in 1 minute after the removal of healing abutments, regardless of the gingival biotype. Repeated connection of prosthetic implant components may be painful because of peri-implant mucosal shrinkage, especially when the implant-abutment connection is located apical to the free gingival margin.2Improved digital impressions of edentulous areas
Intraoral scanners (IOSs) are widely used in the fabrication of fixed dental prostheses, in that their accuracy compares well with traditional impression making.1 Recently, IOSs have been successfully used in the fabrication of removable dental prostheses.2-5 Digital impressions are useful for patients with a gag reflex and sensitivity to impression materials.2-4 Moreover, IOSs can register excessively movable tissue in a passive state to achieve a mucostatic impression.2,3,6,7 However, scanning edentulous area with IOSs may be difficult and time-consuming, because edentulous sites are smooth and devoid of features.An extended guide pin for a direct implant impression
A precise implant impression is essential for the passive fit of an implant superstructure.1-3 Although digital impressions are becoming more popular,4,5 conventional impression techniques are still frequently used. A direct (pick-up) open tray impression technique uses a guide pin.6 When an implant is deeply placed, the guide pin may not extend through the hole of the open tray.7 Therefore, wiping off excessive impression materials through the hole with a gloved finger may be necessary.8 However, this is messy, and the gloves may inhibit the polymerization of polyvinyl siloxane materials.Completely digital approach to an ovate pontic
When a missing maxillary incisor is replaced with a fixed dental prosthesis (FDP), an ovate pontic can be applied for esthetics and less plaque accumulation.1-10 The established tissue beneath an interim ovate pontic may collapse when an interim FDP is removed and an impression is made.10,11 To ensure positive contact and support of the pseudopapillae with a definitive pontic, a stone cast is scraped in this area.10 However, reshaping or porcelain additions to a definitive pontic may be necessary at the evaluation phase, because the scraping is done arbitrarily.Modified interrupted suturing technique for preventing suture irritation
Even though a continuous suturing technique is less time consuming, the failure of any part of the suture may result in loosening along its whole length.1,2 Therefore, horizontal mattress and interrupted suturing techniques are recommended for a guided bone regeneration procedure.3-7 A polypropylene suture (PPS) is also used to avoid wound dehiscence, because a PPS can resist muscle pull with prolonged high tensile strength, knot security, expansion due to swollen soft tissue, and minimal tissue reaction.Technique to provisionally maintain the periimplant soft tissue profile
To reproduce the periimplant soft tissue morphology in a definitive cast, an interim restoration is temporarily removed and used extraorally.1-10 If prosthodontic complications such as ceramic fracture occur during function, a definitive restoration is removed for repair or replacement.11-13A technique for recording the abutment screw angulation of cement-retained implant prostheses
Determining the abutment screw channel of a cement-retained implant restoration with 2 dimensional, photographic, or radiographic records is difficult because of limited information on the abutment screw angulation.1-10 This article describes a technique for registering the abutment screw angulation with 2 digital photographs.Alternative antireflection substance for a digital impression
Obtaining a complete scanned image of a cast metal crown is difficult because of reflection. Therefore, a nonreflecting scan spray is applied in a dental laboratory.1-3An alternative technique for transferring denture-related soft tissue irritation to the denture
The most critical time in the success or failure of a denture is the adjustment period, and the most common complaint is pain caused by soft tissue irritation.1-3 The clinician is responsible for the care of the patient throughout this period; however, detecting and transferring the irritated area to the denture is difficult because the irritated soft tissue is frequently located in the posterior area.1,4 As Loney and Knechtel5 emphasized, pressure-indicating paste is useful for improving the diagnosis and correction of denture-related problems.Altered polyurethane cast for a partial removable dental prosthesis
When a polyurethane cast is used to fabricate a partial removable dental prosthesis, a layer of tinfoil is placed on the edentulous area to prevent chemical bonding between the cast and heat polymerizing resin during processing.1 Even though the soft tissue morphology is accurately reproduced in the polyurethane cast with a digital scanner and rapid prototyping machine, tinfoil easily crumples on the cast, resulting in a rough denture base and occlusal error. This article introduces an altered polyurethane cast to overcome these limitations and facilitate separation from the cast after processing.
