Evaluation of the Accuracy of a New Geometric Approach to Implant Guidance.

PURPOSE: Implant surgical guides are often fabricated using CBCT technology. In this study, an alternative technique is proposed. The aim of this in vitro study was to compare the accuracy of the guide sleeve corrections of a geometric approach to guided surgery to the accuracy of in vitro studies of stereolithographic guides. MATERIALS AND METHODS: Four arch forms were milled from acrylic blocks each with 12 root form sites. Root form inserts were made. Holes were milled in the inserts at arbitrary angles. Guide posts were placed in these sites. Guide sleeves were placed on the posts and connected with light-cured resin to form verification jigs. The goal was to correct the angles of the guide sleeves to a vertical position 90 degrees from the base of the arch forms. The initial angles from the vertical and horizontal positions of the center of each guide sleeve were determined radiographically and geometrically. Horizontal and angle corrections were made using two-piece guide posts. Guide sleeves placed over the corrected guide posts were connected with light-cured resin, forming new verification jigs. The accuracy of the angle correction and the coronal horizontal and apical horizontal deviations of the 3-mm guide sleeves were determined. The experimental sites were divided into two groups to determine if the size of the initial angles of the guide sleeves had any effect on the accuracy of the corrections. RESULTS: The initial angles of the guide sleeves before corrections revealed the mean difference between the two methods of measurements in groups 1 and 2 as 0.36 degrees (P = .14) and 0.69 degrees (P = .07), respectively. A comparison of the angle error measurements from 90 degrees after corrections between the two groups in the mesiodistal and buccolingual planes was not significant. The coronal and apical horizontal deviations after corrections revealed a significant difference between the two groups at the coronal level (P = .005) but not at the apical level (P = .14). In comparison of the methods of the two measurements of the angle error from vertical after corrections, the mean difference was 1.23 degrees (P = .01) and 0.69 degrees (P = .02). CONCLUSION: The in vitro accuracy of the guide sleeve corrections made with the geometric approach for implant guidance was compared to the results of the meta-analyses of in vitro studies of implant placement with stereolithographic guides. The mean errors were smaller and within the recommendations of the EAO Consensus Conference of 2012.

An alternative approach for vestibular extension using temporary coverage of epithelialized palatal grafts.

An alternative approach was used to increase the buccal vestibular depth of two edentulous patients, using free epithelialized palatal grafts. Two edentulous patients presented with shallow vestibules and inadequate keratinized tissue width in the mandibular anterior region. These sites were treated with vestibuloplasty followed by placement of an epithelialized palatal graft. In order to minimize graft movement and possible mechanical trauma to the area, the graft was covered with the buccal flap during the initial stages of healing. The patients maintained an increase in the vestibular depth as well as the keratinized tissue width at 14 months and 5 years postoperatively. Successful outcomes in terms of increase in vestibular depth can be achieved with the use of epithelialized palatal graft that is covered during the initial stage of healing. The dental practitioner fabricating the complete denture should be aware of the advantages offered by this alternative surgical technique.

Implant periapical lesions: etiology and treatment options.

Implant failures due to apical pathology are conditions that have not been extensively studied nor reported in the literature. The implant periapical lesion (IPAL) has different symptoms, and several etiologies have been proposed in the literature. This article reviews cases of IPAL reported in peer-reviewed journals and presents possible treatment options. Analysis of the data collected was performed based on diagnosis, cause of extraction of the natural tooth, location, period of implant placement, implant surface, and treatment approach. Even the data presented in this review are based on few reported cases the etiology of these lesions seems to be multifactorial or with an unknown origin. Contamination of the implant surface, bone overheating during surgery, excessive torquing of the implant, poor bone quality, perforation or thinning of the cortical bone, premature or excessive load over the fixture, fracture of the bone inside the hollow portion of the hollow implant, and an implant placement in an infected maxillary sinus have been discussed. In general, areas around endodontically compromised teeth should be carefully analyzed prior to implant placement to prevent implant failures.

Use of imaging guides in preimplant tomography.

OBJECTIVES: The objective of this study was to quantify the variation in use and type of imaging guides used by community-based specialists and general practitioners during dental implant treatment planning phases. The specific aim of this study was to test the hypothesis that specialists are more likely to use some form of cross-sectional imaging in conjunction with imaging guides during the preoperative assessment of dental implant procedures. STUDY DESIGN: Records from 630 patients with implants (1640 implants) referred for cross-sectional tomography were reviewed. Imaging guide type and implant sites were noted. RESULTS: The distribution of referring dentists by specialty was as follows: general practitioners (42.2%), periodontists (35.1%), oral and maxillofacial surgeons (13.3%), and prosthodontists (7%). Of patients referred for tomograms, 52% were referred without a surgical guide. CONCLUSION: Specialists ordered tomograms in conjunction with imaging guides more often than did general practitioners. Prosthodontists and periodontists preferred to use more restrictive guides than did general practitioners or oral and maxillofacial surgeons.