Putty Index for Tripoding.

Precise orientation and transfer of the selected path of insertion and removal is a critical step in cast removable partial denture prosthesis design. An easy technique for registering the same is described using addition silicon putty and a used diamond disk.

Customized Cheek Plumper with Friction Lock Attachment for a Completely Edentulous Patient to Enhance Esthetics: A Clinical Report.

Prosthetic rehabilitation of a completely edentulous patient should never be restricted to the replacement of missing teeth. The ultimate aim of complete denture treatment should be restoration of the full range of oral functions and esthetics. Slumped cheeks are always a concern for esthetically demanding complete denture patients. This article describes a simple, scientific, cost-effective technique to improve facial esthetics in a completely edentulous patient with the help of a cheek plumper. The technique used here implements the concept of neutral zone to precisely determine the amount of space available for the cheek plumper. The simple friction lock attachments that retained the cheek plumpers on the prosthesis were also fabricated after determining the space available in the appropriate areas. Thus an effort was made to keep the cheek plumpers unobtrusive yet effective to ensure complete integration of the prosthesis into the stomatognathic system.

Design of Complete Dentures by Adopting CAD Developed for Fixed Prostheses.

The demand for complete dentures is expected to increase worldwide, but complete dentures are mainly designed and fabricated manually involving a broad series of clinical and laboratory procedures. Therefore, the quality of complete dentures largely depends on the skills of the dentist and technician, leading to difficulty in quality control. Computer-aided design and manufacturing (CAD/CAM) has been used to design and fabricate various dental restorations including dental inlays, veneers, crowns, partial crowns, and fixed partial dentures (FPDs). It has been envisioned that the application of CAD/CAM technology could reduce intensive clinical/laboratory work for the fabrication of complete dentures; however, CAD/CAM is seldom used to fabricate complete dentures due to the lack of suitable CAD software to design virtual complete dentures although the CAM techniques are in a much advanced stage. Here we report the successful design of virtual complete dentures using CAD software of 3Shape Dental System 2012, which was developed for designing fixed prostheses instead of complete dentures. Our results demonstrated that complete dentures could be successfully designed by the combination of two modeling processes, single coping and full anatomical FPD, available in the 3Shape Dental System 2012.

A modified indirect method for fabricating silicone soft-lined complete dentures.

A method is described of polymerizing silicone soft lining materials with a hard acrylic resin base by using a photoactivated spacer. The use of a photoactivated spacer is convenient because of the ease in determining the correct location covering the attached mucosa but not extending to the border margins. By using this method, the optimum shape and thickness of the spacer can also be ensured. Thus, the long-term durability of soft lining dentures is achieved without invasion by microorganisms or peeling away from the denture margin.

Positioning handle and occlusal locks for the Teeth-in-a-Day protocol.

Positioning handles and occlusal locks have evolved as improvements to the Teeth-in-a-Day protocol. These improvements have enabled a more accurate alignment of the removable dental prosthesis during the conversion prosthesis technique. These improvements can be easily incorporated through computer-aided design and computer-aided manufacturing digital denture fabrication process.

[Quantitative evaluation of fabricating complete denture by computer numerical control in manufacturing dentition and baseplate separately plus adhesive molding].

OBJECTIVE: To quantitatively evaluate the assembly precision of fabricating complete denture by computer numerical control (CNC) in manufacturing dentition and baseplate separately plus adhesive molding. METHODS: The 3D surface data of a standard edentulous maxilla plaster cast model and the temporary base-plate were obtained using an Activity 880 3D scanner. The data (data1) of a complete denture were designed using a set of computer aided design (CAD) software developed by the research group of this study. The pins without undercut were designed as 3D shape of the joining area of the dentition and the baseplate by using the software of Imageware 13.2 and Geomagic Studio 2013. Zero in the top and 0.05 mm in the rest surfaces of the retention pins were set for adhesive clearance. Zenotec T1 (5-axis milling machine) was employed to manufacture polymethyl methacrylate (PMMA) dentition and baseplate. Double sides posterior and one anterior "union teeth" were got. The teeth were inserted into the retention pins in the baseplate and cemented with self-curing resin (Huge Dental Material Co., Ltd). The denture was scanned with the 3D scanner to obtain dataset Data4. Data2 and Data3 registration was set in Data4, Data2 and Data3 were united to gain Data 5. The adhesive clearance on the top of the retentional pins was measured, which was originally designed into 0 mm, and the assembly precision of dentition and baseplate obtained. RESULTS: The average clearance measurements between the dentition and the baseplate: left molar teeth (0.44±0.04) mm, max 0.52 mm, min 0.29 mm; right molar teeth (0.52±0.07) mm, max 0.64 mm, min 0.28 mm; anterior teeth (0.60±0.10) mm, max 0.81 mm, min 0.40 mm; total average clearance (0.52±0.10) mm. CONCLUSION: The adhesive clearance can be controlled to the level of 0.5 mm when the joining part of the artificial teeth and the base was designed into the shape of retentional pins and the artificial dentition divided into 3 parts. We succeeded in using the CAD/ computer aided manufacturing (CAM) technology to fabricate the complete denture. Although the assembly precision of the dentition and the baseplate is not perfect, the results have proved that the technical routes are workable.

Comparison of the linear dimensional accuracy of the maxillary denture teeth by three flask closure methods. An in vitro study.

PURPOSE: This laboratory study conducted to evaluate and compare the influence of different flask closure methods on linear dimensional changes of standardized simulated maxillary complete dentures. MATERIALS AND METHODS: Thirty casts were made from a silicone mold representing an edentulous maxillary arch. Thirty identical maxillary dentures were made and randomly assigned to 3 test groups (A, B, C). In Group A, flasks were placed directly in pressure clamp after trial closure. Group B: The final closure was done in a hydraulic press then transferred to pressure clamp. Group C: After trial closure flask was positioned between the two iron plates of the Restriction System flask closure (RSFC) method. Then linear distances were measured three times before and after polymerization: right incisor to left incisor (RI-LI), right premolar to left premolar (RPM-LPM), right molar to left molar (RM-LM) and left incisor- to- left molar (LI-LM) and right incisor- to- right molar (RI-RM) with the help of digital caliper with an accuracy of 0.01mm. ANOVA and Tuckey's test were used to compare the groups (p < 0.05). RESULTS: Inter molar (LM-RM) width showed the greatest dimensional change after processing and Linear dimensions were not significantly influenced by the packing procedure. CONCLUSION: Within the limitations of this study, Restriction System flask closure (RSFC) method demonstrated a similar performance in reducing the tooth movement when compared with other flask closure methods. The posterior region of the denture may present changes in the tooth position after processing, which need to be clinically adjusted.

Experimental study on the use of spacer foils in two-step putty and wash impression procedures using silicone impression materials.

STATEMENT OF PROBLEM: The 2-step putty and wash impression technique is commonly used in fixed prosthodontics. However, cutting sluiceways to allow the light-body material to drain is time-consuming. A solution might be the use of a spacer foil. PURPOSE: The purpose of this study was to evaluate the influence of spacer foil on the margin reproduction and dimensional accuracy of 2-step putty and wash impressions. MATERIAL AND METHODS: Two methods of creating space for the wash material in a 2-step putty and wash impression were compared: the traditional cutout technique and a spacer foil. Eleven commercially available combinations of silicone impression materials were included in the study. The impressions and the cast production were carried out under standardized conditions. All casts were measured with a 3-dimensional (3D) coordinate measuring machine. Preparation margin reproduction and the diameters and spacing of the stone cast dies were measured (α=.05). RESULTS: The 2 methods showed significant differences (P<.05) in the reproduction of the preparation margins (complete reproduction cutout, 90% to 98%; foil, 74% to 91%). The use of a foil resulted in greater dimensional accuracy of the cast dies compared to the cutout technique. Cast dies from the cutout technique were significantly smaller than the metallic original cast (cutout median, 4.55 mm to 4.61 mm; foil median, 4.61 to 4.64). Spacing between the dies revealed only a few additional significant differences between the techniques. CONCLUSIONS: When spacer foils were used, dies were obtained that better corresponded to the original tooth.

Position of Occlusal Plane in Dentate Patients with Reference to the Ala-Tragal Line Using a Custom-Made Occlusal Plane Analyzer.

PURPOSE: The purpose of this study was to determine which of the three positions on the tragus, (superior, middle, inferior) when joined with the ala of the nose for the ala-tragal line was most parallel to the natural occlusal plane in dentate patients. MATERIAL AND METHODS: This study was carried out on 500 individuals, selected randomly and who agreed to participate in the study. A custom-made occlusal plane analyzer was used to check the parallelism between the ala-tragal line and the occlusal plane. The tragus was divided into three parts: superior, middle, and inferior. The instrument was placed in the participant's mouth, and the posterior points on the tragus were determined. RESULTS: For the 500 dentate participants in this study, the most common location of the posterior point on the tragus was the inferior part of the tragus (50.8%). The second most common location of the tragus was the middle part (24.7%), followed by the superior location (12.1%). CONCLUSION: The results of this study indicated that the occlusal plane was found parallel to a line joining the ala of the nose and the inferior part of the tragus in a slight majority of the participants.

An Efficient and Cost-Effective Technique to Construct an Intraoral Central Bearing Tracing Device.

Intraoral central bearing tracing has been shown to be a predictable way of recording and verifying centric relation position for patients. Existing tracing devices are challenging to use due to several significant clinical limitations. In comparison to commercially available counterparts, this article presents a technique that simplifies instrumentation and clinical steps to make an intraoral tracer for making centric relation records, determining occlusal vertical dimension, and detecting deflective occlusal contacts in edentulous patients.

[COMBINED ACRYLIC-POLYPROPYLEN REMOVABLE PROSTHESES FOR PROSTHODONTIC TREATMENT].

The article deals with the development of methods to prevent complications with prosthetic dentures patients with psychiatric status. The authors developed a method of manufacturing the denture using modern thermoplastic materials, the use of which in practice does not cause prosthetic stomatitis in patients with psychiatric status. The proposed methodology has been tested clinically. Based on Schiller- Pisarev and study fixation of prostheses has been shown the advantage of the prosthesis used for prosthetics partial dentition defects that can not be fixed prosthetics in this category of patients.

Prosthetic procedure for simultaneous immediate loading of opposing edentulous arches.

For patients with complete edentulism, a significant problem is the transfer of diagnostic data to the definitive casts when an immediate loading technique is used. This article presents a prosthetic procedure to allow simultaneous treatment of opposing edentulous arches with immediate implant loading. This technique uses 2 occlusal acrylic resin devices to transfer the diagnostic cast information to the definitive casts. Esthetic and functional fixed dental prostheses are fabricated from diagnostic information acquired in the presurgical phase without any impression or recording of the maxillomandibular relationship during or after surgery. This methodology is applicable when the simultaneous immediate loading of implants in 2 edentulous arches is indicated.

A method for fabrication of implant-supported fixed partial dentures.

When restoring a partially edentulous arch with an implant-supported fixed partial denture, the optimal fit and function of the final restoration depend on the fabrication of an accurate impression and the registration of the interocclusal relationship. The present case report presents a method for the fabrication of impressions and the registration of the interocclusal relationship for implant-supported partial dentures. The described method allows the accurate transfer of the implant position and the registration of the interocclusal relationship using transfer key and electroformed gold copings. The key and copings were used to transfer the intraoral implant position to the cast, to position the abutments intraorally, and to facilitate the fabrication of the final partial denture.

A comparison of the accuracy of three removable die systems and two die materials.

The purpose of this study was to evaluate the dimensional shift of three commonly used die systems (Conventional system, Pindex system, Di-Lok tray system) with two commercially available type IV die stones (Ultra rock and Pearl stone). Under controlled conditions, ten casts, each with two removable dies, were constructed for each system for a total of 30 casts and 60 removable dies. Before and after sectioning measurements to within 0.01 mm in horizontal and vertical planes were recorded and differences calculated. Data were analyzed with 't' tests, one way analysis of variance and post hoc Tukey test. The results demonstrated that among the die systems compared, no single system was superior to the others in all respects. But among the die materials, dies poured in Pearl stone exhibited more dimensional changes than Ultra rock (p<0.05). Selection of die material is as critical as selection of any particular die system for successful fabrication of fixed partial denture and implant prosthesis.

Direct custom implant impression copings for the preservation of the pontic receptor site architecture.

The direct custom implant impression coping technique is designed to record the periimplant gingiva and pontic receptor site after the tissues have been shaped with a provisional restoration. The technique prevents inaccurate recording of the gingival architecture by using a dual polymerizing composite resin placed into the sulcus and pontic receptor sites and adapted to the open tray implant impression copings. This technique may improve soft tissue accuracy between the clinical condition and the laboratory cast.

Effect of double flasking and investing methods on artificial teeth movement in complete dentures processing.

PURPOSE: The aim of this study was to evaluate linear dimensional alterations of artificial teeth for complete dentures when using different investment and flasking techniques. BACKGROUND: Dimensional changes in the vertical dimension may occur owing to changes in artificial teeth positioning caused by different investing and flasking techniques. MATERIALS AND METHODS: Thirty pairs of the complete dentures were manufactured and randomly divided into three groups (n = 10): (1) invested with type III stone in monomaxillary PVC flask; (2) invested with type III stone in bimaxillary PVC flask; and (3) invested with laboratory silicone in bimaxillary PVC flask. Dentures were polymerised by microwave, and 12 linear distances were measured before and after denture processing. Data were analysed by one-way anova, considering manufacturing technique as the study factor. Tukey's HSD was used as post hoc ANOVA (p = 0.05). RESULTS: Most of the linear distances were comparable for all groups. All transversal maxillary and mandibular distances were higher for group 1 compared with groups 2 and 3 (p < 0.05), except the distance 3-6 for mandibular arch, in which no difference was found between groups (p < 0.05). Both maxillary diagonal distances were higher in group 1 (p < 0.05), and no differences were found among all groups for mandibular measurements. CONCLUSIONS: Double flasking technique independent on the investment material is shown to be the most effective method to reduce changes in artificial teeth positioning.

A functional open-tray impression technique for implant-retained overdenture prostheses.

Several implant impression techniques with different materials have been described in the literature. Generally, border molding, functional, and final impressions have been made with 3 different materials, which makes the procedure technique-sensitive and time-consuming. A combination of open-tray and functional impression techniques is described in this technical report. Border molding and functional impression procedures are made at the same time using a vinyl polysiloxane impression material, which makes this technique a simple and time-efficient alternative for clinicians.

Simple method of record base fabrication for a bar-retained implant overdenture.

A record base should be stable and accurately transferable from the cast to the mouth. This article describes a simple and practical method of fabricating a record base for mounting a master cast used to fabricate an implant connecting bar for an implant-retained overdenture.

A new intraoral device to facilitate preparation of the guide plane for removable dental prostheses.

This article presents a prototype of an intraoral device that facilitates preparation of parallel guide planes with accuracy and minimal occlusal divergence. The design of this device facilitates transfer of the desired path of insertion from the diagnostic cast to the mouth quickly and efficiently.

A starter's guide to preclinical teeth arrangement: simplified clinometer.

UNLABELLED: Arrangement of artificial teeth in a bilaterally symmetrical fashion with proper inclinations of teeth had been a challenging task for beginners. A variety of tools and guiding equipment have been developed to help students to learn teeth arrangement. Unfortunately, those tools were either costly or unsuitable for use with mean value articulators. This article attempts to introduce a simplified clinometer which can be attached to mean value articulator and can be used as a guide to arrange teeth in a bilaterally symmetrical manner by the undergraduates in both clinical and preclinical set-up. CLINICAL SIGNIFICANCE: Training of the future dentists in sound esthetic principles in a preclinical environment, using this device, will increase the final clinical efficacy of their work. AIM: The aim of this article is to provide a simple but effective device to undergraduate students to help them learn teeth arrangement easily and systematically.