Comparison of Tooth Size Measurements in Orthodontics Using Conventional and 3D Digital Study Models.

(1) Background: The objective of this study was to assess which digitization method produces the biggest deviation in the 3D images of tooth size from plaster models made using alginate impressions, which are considered the gold standard in orthodontics. (2) Methods: The sample used in this study included 30 subjects (10 males and 20 females). Measurements were made on four types of models: (1) digital models obtained through intraoral scanning and digitized models of plaster cast made from (2) alginate impressions, (3) silicone impressions, and (4) conventional plaster models. Mesio-distal (MD) and buccal/labial-lingual/palatal (BL) dimensions were measured on the reference teeth of the right side of the jaw (central incisor, canine, first premolar, and first molar). Comparisons of tooth size between the methods were conducted using a repeated measurement analysis of variance and the Friedman test, while the intraclass correlation coefficient was used to determine agreement between the different methods. (3) Results: The results showed a similar level of agreement between the conventional and digital models in both jaws and the anterior, middle, and posterior segments. Better agreement was found for the MD measurements (r = 0.337-0.798; p ≤ 0.05) compared to the BL measurements (r = 0.016-0.542), with a smaller mean difference for MD (0.001-0.50 mm) compared to BL (0.02-1.48 mm) and a smaller measurement error for MD (0.20-0.39) compared to BL (0.38-0.89). There was more frequently a better level of agreement between 3D images than measurements made using a digital caliper on the plaster models with 3D images. (4) Conclusions: The differences in measurements between the digital models and conventional plaster models were small and clinically acceptable.

Bone Shell Technique with Relocated Crestal Ridge Segment for Anterior Horizontal Mandibular Ridge Atrophy: A Case Series.

Horizontal and vertical ridge augmentation via the bone shell technique provides predictable outcomes. The external oblique ridge is the most-used donor site for bone plate harvesting, followed by the mandibular symphysis. The lateral sinus wall and the palate have also been described as alternative donor sites. This preliminary case series reports a bone shell technique that used the coronal segment of the knife-edge ridge as a bone shell in five consecutive edentulous patients (20 sites) with severe mandibular horizontal ridge atrophy and adequate ridge height. The follow-up period was 1 to 4 years. The average horizontal bone gains at 1 mm and 5 mm below the newly formed ridge crest were 3.6 ± 0.76 mm and 3.4 ± 0.92 mm, respectively. Ridge volume was sufficiently restored in all patients to enable implant placement in a staged approach. In 2 of the 20 sites, additional hard tissue grafts were required at implant placement. The advantages of utilizing the relocated crestal ridge segment are as follows: The donor and recipient sites are the same, no major anatomical structures are compromised, periosteal releasing incisions and flap advancement are not required for primary wound closure, and the risk of wound dehiscence is minimized due to reduced muscle tension.

VISTA Approach in Conjunction with Enamel Matrix Derivative, Corticocancellous Bone, and Connective Tissue Graft for Periodontal Defect Surgery: A Case Series.

The biggest challenge during periodontal regeneration in the anterior region is the prevention of soft tissue recession. Minimally invasive surgeries, particularly papilla preservation techniques and soft tissue augmentation, may significantly reduce such postoperative soft tissue recession. This article presents the vestibular incision subperiosteal tunnel access (VISTA) approach for periodontal regeneration in the anterior region. A subperiosteal tunnel prepared from a single vertical vestibular incision adjacent to the defect is used for debridement, application of enamel matrix derivative, defect grafting with corticocancellous tuberosity bone, and insertion of the connective tissue graft. Evaluation of six cases with up to 6 years of follow-up showed improvements in all clinical parameters. The probing pocket depth improved from 8.2 ± 0.75 mm initially to 2.7 ± 0.52 mm at follow-up, clinical attachment level improved from 8.5 ± 0.83 mm initially to 2.7 ± 0.52 mm at follow-up, and midfacial gingival recession of 1 mm at two sites was corrected. The papillae were stable at all sites, with an average distance of 4.8 mm from the incisal edge to the papilla tip. This technique seems to be a promising approach for achieving both esthetic and functional goals of periodontal regenerative surgery. However, experience in performing microsurgeries and harvesting tuberosity tissues may be a limitation.

The socket shield technique with proximal extensions for single-rooted teeth.

The conventional socket shield (SS) design extends from the mesiolabial to the distolabial line angle. C-shaped SS, L-shaped SS, and proximal SS designs have proximal extensions that help to maintain the hard and soft tissue in the interproximal areas. This is beneficial for implant sites adjacent to an existing implant or an edentulous space. The most common complication of the socket shield technique (SST) is internal shield exposure. Due to anatomical features such as a scalloped ridge shape and an oval socket shape of some teeth, the risk of complications such as internal shield exposure, inadvertent SS displacement, and fracture of the SS during implant insertion is greater in proximal shield areas. The present article describes guidelines for case selection for proximal shield extensions, along with SS preparation and the selection of implant and prosthetic components.