Prosthetic rehabilitation of intraoral defects in patients with rhino-orbital-cerebral-mucormycosis: A systematic review.

AIM: This study aimed to systematically review the frequency and type of intraoral prosthetic rehabilitation in patients with rhino-orbital-cerebral-mucormycosis (ROCM). SETTINGS AND DESIGN: Systematic review following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. MATERIALS AND METHODS: An electronic search was conducted in databases including PubMed, Web of Science, Scopus, and Google Scholar. Case reports that documented prosthetic rehabilitation following surgery in patients with ROCM were included. This review was registered under the International Prospective Register of Systematic Reviews CRD42021262284. Assessment of the quality of the included studies was done using the Joanna Briggs Institute Critical Appraisal Checklist for Case reports, which comprised of an eight-item checklist. The recorded observations were organized and subjected to analysis. STATISTICAL ANALYSIS USED: Qualitative analysis was used. RESULTS: Among the 25 case reports, type IId defect was the most common. Three types of prosthetic treatments were rendered, with the obturator being the most common choice of rehabilitation, followed by implant-retained obturator overdenture and fixed implant-supported prosthesis. Patients undergoing implant-based rehabilitation exhibited a 100% survival rate for implants, with follow-up periods spanning from 6 months to 3 years. No prosthetic complications were reported in any of the included case reports. CONCLUSIONS: The prevailing defect type identified was IId (48%), while the treatment of choice most frequently employed was an obturator (84%). However, with limited evidence available at present, further research is required to draw more definitive conclusions.

Digital superimposition of scans for recording and transferring vertical relation from provisional restorations when rehabilitating worn-out dentition: A dental technique.

Excessive wear of the natural dentition results in the loss of tooth anatomy and the vertical dimension of occlusion (VDO) which may necessitate full mouth rehabilitation. Successful full-mouth rehabilitation with increased VDO requires accurate recording and transfer of the newly raised VDO with provisional restorations. Conventional bite registration can incur errors during the recording and transfer of vertical dimensions. This article introduces a digital approach-the superimposition of scans using an intraoral scanner (IOS) to transfer VDO, occlusion, and aesthetic data from provisional restorations for designing and fabricating indirect restorations in the management of worn-out dentition.

Surface trueness and precision of interim restorations fabricated by digital light processing and CAD-CAM milling systems.

STATEMENT OF PROBLEM: The development of digital dental technologies has enabled clinicians to use additive and subtractive manufacturing techniques to fabricate interim restorations. However, knowledge of the trueness and precision of such restorations fabricated using digital light processing (DLP) and computer-aided design and computer-aided manufacturing (CAD-CAM) methods is limited. PURPOSE: The purpose of this in vitro study was to assess and compare the accuracy of interim crowns fabricated using DLP and CAD-CAM methods. MATERIAL AND METHODS: A typodont mandibular first molar was prepared for a ceramic crown, and a digital scan (Medit T500) was obtained to design interim crowns by using the CAD software program. The CAD data were designated as the reference data. A total of 20 crowns were fabricated by DLP and CAD-CAM technology. The fabricated interim crowns were further scanned using a laboratory scanner and were superimposed with the CAD data by using a 3-dimensional (3D) point cloud assessing software program (CloudCompare) for the evaluation of trueness and precision. Root mean square values (RMS) were obtained for the evaluation of discrepancies. The Student t test was used to compare data as the Shapiro-Wilk test confirmed the normal distribution. RESULTS: RMS values for the trueness values of the external and intaglio surfaces of the 3D printed and milled interim crown displayed no statistically significant differences (P>.05). Precision for the external surface reported significance (P<.05), whereas that for the intaglio surface reported no significance (P>.05). CONCLUSIONS: The accuracy of interim crowns fabricated by using DLP was comparable with that of milled crowns. Both manufacturing systems produced a true reproduction of the CAD. As for precision, the external surface of the DLP interim crown was statistically different from that of the milled group as it relates to the CAD.

A clinical study to evaluate the reliability of light-correcting devices in clinical shade selection.

Background: Visual and advanced instrumental methods are the most common tools for shade selection. The instrumental methods are considered reliable and provide quantifiable values, but the high cost puts them out of the reach of most dentists. Light-correcting devices provide an economical alternative for clinical shade selection. The aim of this study was to assess the reliability of the light-correcting device in clinical shade selection. Materials and Methods: The in vivo experimental prospective study sample included 60 volunteers aged 18-25 years, with no severe enamel pigmentation or anomaly in anterior maxillary teeth. Two observers performed visual shade matching of the maxillary right central incisor without a light-correcting device and later with a light-correcting device at the same time of the day at an interval of 1 week. The shades were confirmed with the control value obtained by using a spectrophotometer. Each observer was blinded to the shade color selected by the other examiner. The data collected were subjected to the statistical analysis. The shade measured with the light-correcting device and without its use was compared with the control shade obtained by the spectrophotometer. The value closer to the control shade value was considered accurate, and the method used for shade matching would be considered reliable. The Fleiss kappa statistical test was used to assess the reliability of each method. P ≤ 0.05 was considered statistically significant. Results: Using a light-correcting device significantly increased the reliability of the visual shade selection method. When compared to the shades recorded by the spectrophotometer (control), the use of a light-correcting device as an aid in visual shade selection showed more accurate and reliable results as compared to the visual shade selection without a light-correcting device (P < 0.05). Conclusion: Light-correcting devices can assist in reliable shade selection and allow better communication with the dental laboratory technician to provide predictable esthetic results.

Three-dimensional finite element analysis of zygomatic implants for rehabilitation of patients with a severely atrophic maxilla.

STATEMENT OF PROBLEM: Stresses applied to zygomatic implants have been determined to be transferred mainly to the zygomatic bone; however, consensus regarding the stress distribution pattern in the bone surrounding zygomatic implants has not yet been reached. PURPOSE: The purpose of this 3-dimensional (3D) finite element analysis (FEA) study was to visually compare the stress distribution pattern in 2 different zygomatic implant treatment modalities and evaluate the effect of masseter musculature involvement. MATERIAL AND METHODS: A 3D FEA craniofacial model was constructed from the computed tomography (CT) data of a selected patient with a severely atrophic edentulous maxilla. Modeled zygomatic and conventional implants were inserted into the craniofacial model supporting a prosthesis superstructure. Two types of treatment were considered in the study: 2 zygomatic implants placed bilaterally or 2 zygomatic implants placed in conjunction with at least 2 conventional implants at the anterior maxilla. The models were loaded with a vertical force of 150 N, a lateral force of 50 N, and a distributed occlusal force of 300 N applied to the insertion area of the masseter muscle. The stresses on and deformations of the bones and implants were then observed and compared with and without the involvement of the musculature component. RESULTS: The stresses were distributed efficiently along the vertical and horizontal facial buttresses, as in the dentate skull; however, a difference in distribution pattern was observed when the models were loaded without applying the muscle component. The maximum deformation of bones surrounding the implants occurred in the abutment connection of the conventional anterior implant in the model with an additional conventional anterior implant. CONCLUSIONS: The FEA revealed the stresses were distributed efficiently along the vertical and horizontal facial buttresses, as in the dentate skull. However, the stresses in both models were concentrated in the zygomatic bone when incorporating the muscle component. Therefore, incorporating muscular force into FEA studies could affect the analysis result.

A smartphone application with a gray card for clinical shade selection: A technique.

Shade selection is an inherently complex procedure, and its accurate reproduction in the definitive restoration involves an in-depth understanding of color science and its effective communication with the dental laboratory technician. A technique is presented that uses a smartphone application (Snapseed; Google LLC) and a gray card for clinical shade selection.

A User-Friendly Technique for Replacing Nylon Inserts of a Locator Attachment.

Rehabilitation of edentulous patients with implant-supported overdentures has gained prominence over the use of conventional dentures because of the improved quality of life it provides patients. Various attachment systems are available that facilitate the insertion and removal of prostheses, and among them, the Locator attachment system has become popular due to its self-aligning property, simplicity of use, and minimal space requirement of male inserts within the denture. However, the loss of retention of nylon inserts over time requires their removal from the metal housing and subsequent replacement. This article describes an easy alternative technique for replacing the nylon inserts in the denture cap using a simple dental explorer and mirror head.