Single-Appointment Fabrication of Interim Immediate Denture: A Clinical Report

Objective: An immediate complete denture is fabricated before the extraction of all teeth. It has several advantages such as preservation of esthetics, muscular tone, normal speech and reduction of post-operative pain. This report describes a method of using patient’s current fixed partial denture (FPD) for single-appointment construction of interim immediate denture.Case: We used patient’s existing maxillary FPD for single-appointment fabrication of an interim immediate denture; which was delivered to the patient after the extraction of his remaining maxillary teeth.Conclusion: Within a short time, an interim immediate denture can be fabricated for patients to preserve occlusion, vertical facial height and facial appearance until the fabrication of final prosthesis

Report of a Case of Hypodontia due to Ectodermal Dysplasia: Early Rehabilitation with Overdenture

Alveolar ridge is underdeveloped in ectodermal dysplasia (ED). The available treatment plans include fixed, removable or implant-supported prostheses, alone or in combination.A 5 year-old boy was referred for treatment to the Department of Prosthodontics, Tehran University of Medical Sciences with the chief complaint of missing teeth. Prosthodontic treatment was performed to improve mastication, esthetics, phonetics, and psychological support. Altering the alveolar height also provided a more pleasant musculocutaneous profile. Series of overdentures were fabricated in the same conventional manner to compensate for the patient’s growth.Early treatment had a major impact on self-esteem, masticatory function, speech and facial esthetics of our patient. However, long-term success depends on regular recall appointments.

Simple Method for Converting Conventional Face-bow to Postural Face-bow for Recording the Relationship of Maxilla Relative to the Temporomandibular Joint.

A fundamental assumption in prosthetic dentistry is that the axis-orbital plane will usually be parallel to the horizontal reference plane. Most articulator systems have incorporated this concept into their designs and use orbitale as the anterior reference point for transferring the vertical position of the maxilla to the articulator. Clinical observations of Cantonese patients suggest that in some individuals the Frankfort plane may not be horizontal, thus the orientation of the casts in the articulator is incorrect with respect to the horizontal plane. The purpose of this study was to introduce a simple method for converting the conventional face-bow to postural face-bow to reproduce the orientation of the occlusal plane relative to the true horizontal plane with the patient in Natural Head Posture (NHP)

Effects of Length and Inclination of Implants on Terminal Abutment Teeth and Implants in Mandibular CL1 Removable Partial Denture Assessed by Three-Dimensional Finite Element Analysis

Objectives: This study sought to assess the effects of length and inclination of implants on stress distribution in an implant and terminal abutment teeth in an implant assisted-removable partial denture (RPD) using three-dimensional (3D) finite element analysis (FEA).   Materials and Methods: In this in vitro study, a 3D finite element model of a partially dentate mandible with a distal extension RPD (DERPD) and dental implants was designed to analyze stress distribution in bone around terminal abutment teeth (first premolar) and implants with different lengths (7 and 10 mm) and angles (0°, 10° and 15°). Results: Stress in the periodontal ligament (PDL) of the first premolar teeth ranged between 0.133 MPa in 10mm implants with 15° angle and 0.248 MPa in 7mm implants with 0° angle. The minimum stress was noted in implants with 10mm length with 0° angle (19.33 MPa) while maximum stress (25.78 MPa) was found in implants with 10mm length and 15° angle. In implants with 7 mm length, with an increase in implant angle, the stress on implants gradually increased. In implants with 10 mm length, increasing the implant angle gradually increased the stress on implants. Conclusion: Not only the length of implant but also the angle of implantation are important to minimize stress on implants. The results showed that vertical implant placement results in lower stress on implants and by increasing the angle, distribution of stress gradually increases. Keywords: Dental Implants, Single-Tooth; Dental Stress Analysis; Finite Element Analysis

8186266913Determination of Incisal Point as Anterior Guide to Transfer Maxillary Casts to Articulator: A Pilot Study

Objectives Despite the importance to use face-bow record for transferring maxillary cast to articulator some dentists use average points to avoid the time taken and ease of use. The location of incisal point could help to set the maxillary cast or denture in an appropriate position in mounting stage. This study was designed to determine the incisal point location in antero-posterior and vertical dimensions in different facial forms and genders.Methods Dental casts were obtained from the maxillary jaw of 44 dental students (male and female) and subsequently transferred to the articulator using an ear bow. The three dimensional location of the incisal point in relation to condylar axis was determined using a Coordinated Measuring Machine (CMM).Collected data were compared between male and female participants as well as those of oval, squared and tapered faces. For data analysis Student t test was employed to make the comparisons.Results The mean distance between the incisal point and the center of the condylar axis in antero-posterior and vertical dimensions was 81.28 mm and 42.85 mm respectively. The mean antero-posterior distance was significantly higher among male students (Ρ<0.05). The mean vertical dimensions did not show any significant difference between male and female students (P>0.05). In square facial form, the mean antero-posterior distance was significantly higher compared to the ovoid facial form (P<0.05).Conclusion The differences on incisal points were significant between the two genders only in antero-posterior dimension. A similar finding was noted on square facial form when compared to ovoid facial form.  The incisal point was more consistent with the Frankfurt mounting platform compare to Bonwill index

Influence of Implant Position on Stress Distribution in Implant-Assisted Distal Extension Removable Partial Dentures: A 3D Finite Element Analysis.

Distal extension removable partial denture is a prosthesis with lack of distal dental support with a 13-fold difference in resiliency between the mucosa and the periodontal ligament, resulting in leverage during compression forces. It may be potentially destructive to the abutments and the surrounding tissues. The aim of this study was to assess the effect of implant location on stress distribution, in distal extension implant assisted removable partial dentures.Three-dimensional models of a bilateral distal extension partially edentulous mandible containing anterior teeth and first premolar in both sides of the arch, a partial removable denture and an implant (4×10mm) were designed. With the aid of the finite element program ANSYS 8.0, the models were meshed and strictly vertical forces of 10 N were applied to each cusp tip. Displacement and von Mises Maps were plotted for visualization of results.When an implant was placed in the second premolar region, the highest stress on implant, abutment tooth and cancellous bone was shown. The lowest stress was shown on implant and bone in the 1(st) molar area.Implants located in the first molar area showed the least distribution of stresses in the analyzed models