Modeling Plastic Impression Compound Research Articles

The effect of bioelectric and manual impressions on quality of complete dentures and quality of life: A cross over pilot study

PurposeTo compare the quality of complete dentures and quality of life of participants rehabilitated by using TENS (Transcutaneous electric nerve stimulation) facilitated impression making with manual impressions. Material and methodsTen completely edentulous participants were enrolled in the crossover, pilot study. Participants were randomized in 2 groups. Five participants in each group were rehabilitated by dentures fabricated with TENS facilitated definitive impression technique (group T) and conventional impression technique (group C). In group T, Bioelectric border molding was done for the participants, that uses electric stimulation of the nerves supplying the muscles. In group C, incremental border molding using modeling plastic impression compound was carried out. Participants in each group used the dentures for 3 months. After 3 months, OHIP-EDENT questionnaire responses were obtained from the participants to observe the oral health related quality of life. A dental specialist recorded denture quality by Kapur scoring criteria. After one month wash period, the treatment was swapped between the groups. OHIP-EDENT scores and Kapur score were recorded for the alternate dentures after 3 months of use. Descriptive analysis was followed by Mann Whitney test to compare the overall scores between group T and group C for OHIP-EDENT, the scores for individual domains of OHIP-EDENT, and Kapur score for denture evaluation (α = 0.05). ResultsThe overall OHIP-EDENT scores within each domain were less in group T when compared with the scores in group C and Kapur score for group T was more than group C. The difference was statistically significant i.e. P = 0.002 & 0.003 respectively. ConclusionsLess OHIP-EDENT scores in group T imply better perception of quality of life of individuals due to better performance of stomatognathic system. The higher Kapur scores in group T signifies better quality of dentures when TENS was used for definitive impression making.

Aluminum barrier laminate or plastic tube as a dispenser for modeling plastic impression compound for border molding

Aluminum barrier laminate or plastic tube as a dispenser for modeling plastic impression compound for border molding

Fabrication of a Feeding Obturator for Infants.

Large clefts in the lip and palate are common congenital anomalies. If the cleft palate is large enough, conventional feeding techniques may not provide proper nutrition for the infant. Feeding obturators will aid in the ability of the infant to attain suction and help the infant to feed adequately. It is necessary for the infant to have sustained weight gain prior to surgery to correct the cleft lip and/or palate. Fabrication of an infant feeding obturator is a simple technique using materials found in every dental office. An impression is made using modeling plastic impression compound. This impression is relined using irreversible hydrocolloid, and the resulting cast is used to enable a vacuum-formed obturator to be fabricated. The vacuum-formed obturator is smoothed and adjusted in the infant's mouth to ensure closure of the palate but allows pace posteriorly to allow normal breathing. The resulting obturator is well retained in the infant's mouth, allowing feeding.

An investing technique for the obturator section of a pharyngeal speech aid prosthesis

A pharyngeal speech aid prosthesis is used to separate the nasopharynx and oropharynx during speech and deglutition, and represents a prosthetic solution for palatopharyngeal insufficiency. The conventional prosthesis consists of an oral section composed of a cast partial dental prosthesis framework with a perforated palatal extension to support the obturator section. This perforated palatal extension facilitates the placement and retention of high-fusing modeling plastic impression compound and, subsequently, added mouth temperature wax to form the obturator section.

A Complete Denture Impression Technique Survey of Postdoctoral Prosthodontic Programs in the United States

The purpose of the study was to survey program directors of postdoctoral prosthodontic programs in the United States regarding their programs' complete denture impression techniques. The key objectives of the survey were to identify the current trends in complete denture impression making and to determine which techniques and materials are taught in US postdoctoral prosthodontic programs. An online survey was sent to all program directors of US postdoctoral prosthodontic programs. The survey comprised two sections: preliminary impressions and final impressions. The survey contained 22 questions that would take approximately 5 minutes to complete. All responses remained anonymous throughout the survey. The response rate for the survey was 87%. A majority of the programs did not separately border mold the tray prior to making the preliminary impressions (82%). The impression material of choice for the preliminary impression was irreversible hydrocolloid (88%). Selective pressure was the predominantly used impression philosophy (80%). All programs border molded the custom tray, and 95% recorded the borders in sections. The material of choice for border molding the custom tray was modeling plastic impression compound (71%). The most commonly used impression material for the final impressions was polyvinylsiloxane (PVS) (42%), and the second most commonly used impression material was polysulphide (32%). The most common technique for locating the posterior palatal seal was marking intraorally and transferring onto the final impression (65%). Most programs routinely advised their patients not to wear their existing dentures for at least 24 hours before the final impressions were made (83%). Based on the results of this study, the following conclusions can be drawn: (1) The most commonly used material for the preliminary impression was irreversible hydrocolloid and for the final impression was PVS. (2) Modeling plastic impression compound was used by most programs to border mold the custom trays. (3) Selective pressure was the predominantly used impression philosophy. (4) A majority of the programs made a special consideration for excessive movable (flabby) tissue. (5) Most programs routinely advised their patients to not wear their existing dentures for at least 24 hours before the final impressions were made.

Predoctoral Prosthodontic Curricula on Removable Partial Dentures: Survey of Turkish Dental Schools

This study was conducted to evaluate the predoctoral removable partial denture (RPD) curricula in Turkish dental schools in regards to materials, techniques, and approaches. A questionnaire consisting of eighteen multiple-choice questions was sent by e-mail to the senior members of the prosthodontic departments of seventeen long-established dental schools in Turkey. The response rate was 100 percent. All schools (100 percent) used custom trays for making final impressions of partially dentate arches, taught border molding of the custom tray for the edentulous areas, used modeling plastic impression compound in border molding the final impression trays, and used base metal alloys for RPD frameworks. None of the schools had an in-house laboratory that fabricates RPD frameworks, and none of the students cast the frameworks of their own RPDs. The majority of schools used irreversible hydrocolloid as a final impression (70.6 percent) and dental surveyor (76.5 percent) in the designing of RPDs. The majority of schools did not flask their own RPDs (64.7 percent), did not treat patients using RPDs with attachments (76.5 percent), and did not perform the altered cast technique in bilateral and unilateral distal extension RPD cases (76.5 percent). Six teen schools (94.1 percent) had a minimum number of RPD arches that a student must complete in order to graduate. It was found that predoctoral RPD curricula in Turkish dental schools were both variable and similar.

Temperature modification of a hot glue gun for use with modeling plastic impression compound

Temperature modification of a hot glue gun for use with modeling plastic impression compound

Modified fluid wax impression for a severely resorbed edentulous mandibular ridge

This article describes a technique for making a definitive impression for highly displaceable residual ridges. The technique is especially applicable for mandibular edentulous ridges. The choice of the impression materials, as well as the design of the impression tray, focuses on preventing distortion of the displaceable residual ridges during impression making. Using an impression tray with an opening, modeling plastic impression compound and impression wax are used to accurately capture the shape of the residual ridge and place pressure onto denture load-bearing areas. Low-viscosity vinyl polysiloxane impression material is then used over the window opening to capture the surface details of the residual ridge without distorting the displaceable tissues. The use of this technique helps in maintaining the contour and capturing the detail of the tissues, as well as in accurately determining the extent of the muccobuccal denture extensions.

Morphologic comparison of two neutral zone impression techniques: A pilot study

Several studies have compared dentures fabricated using neutral zone and conventional techniques. However, studies comparing swallowing and phonetic techniques for assessing the location and shape of the neutral zone could not be identified in the literature. The purpose of this pilot study was to compare the outline form of the phonetic and swallowing neutral zone impression techniques for the same subjects. Nine denture wearers with advanced mandibular ridge resorption were included in this study. For each subject 2 trays were prepared in autopolymerizing acrylic resin. One method used phonetics and tissue conditioner to shape the neutral zone; the second method used swallowing and modeling plastic impression compound. The resulting neutral zone impressions were leveled to the same occlusal height by gently grinding the occlusal surface on sandpaper until it corresponded with landmarks (corners of the mouth, two thirds of the height of the retromolar pads, bilaterally) noted on the cast. The impression was inverted onto graph paper, and the contour was outlined with a lead pencil. One impression was made for each subject, for each technique. The buccal contours of both neutral zones coincided at the median line. The maximum distance between the zones was measured in a buccolingual direction in the anterior, premolar, and molar regions bilaterally. When the location of the phonetic neutral zone in relation compared to the swallowing neutral zone was buccally oriented, a plus score was given. When the phonetic neutral zone was lingually located, a minus score was given. When the 2 lines coincided, a score of 0 was given. Measurements were made from direct readings on the graph paper. Statistical analysis was performed using the Sign test (alpha=.05). Significant differences were noted buccally in the left molar (P =.031) and right molar (P =.003) regions and also in the left and right premolar regions (P =.007), where the swallowing neutral zone was found to be located buccal to the phonetic neutral zone. Significant differences were also noted lingually, in the right premolar region (P =.015), where the swallowing neutral zone was found to be located lingual to the phonetic neutral zone. There was no significant difference between the techniques for the anterior region. Within the limits of this study, the phonetic neutral zone appears to be narrower posteriorly compared to the swallowing neutral zone, thus limiting premolar and molar positioning.

Current concepts and techniques in complete denture final impression procedures.

In 2001, a survey of U.S. dental schools was conducted to determine which concepts, techniques and materials are currently prevalent in the teaching of final impression procedures for complete dentures in the predoctoral clinical curriculum. The questionnaire was mailed to the chairperson of the prosthodontic/restorative departments of 54 U.S. dental schools. Of these, 44 schools returned the completed survey resulting in a response rate of 82%. Results from this survey show that the majority of schools (71%) teach the selective-pressure technique for final impression making; the majority of the schools (64%) use modeling plastic impression compound for border molding the final impression tray; 39% of the schools do not place vent holes in the final impression tray, 30% of schools place more than one hole and 27% place one hole only; the majority of the schools (98%) are using custom trays for final impressions. Ninety-eight percent of the schools are border molding the custom tray and 70% of schools are using a visible light-cured (VLC) composite resin material to make the trays. Thirty-six percent of the schools are teaching the Boucher impression technique and 34% are teaching the modified Boucher impression technique. Predoctoral clinical complete denture educational programs agree on many aspects of final impression making, however, there is variability in their teachings regarding the impression philosophy and the materials used.

Using the neutral zone to obtain maxillomandibular relationship records for complete denture patients

A technique for obtaining maxillomandibular registration for complete denture patients is presented. The maxillary rim is formed with the use of conventional techniques. The mandibular rim is made from modeling plastic impression compound on a record base formed by the patient into the neutral zone. The mandibular rim then is reheated, and the patient determines the occlusal vertical dimension by swallowing. An imprint of the maxillary rim is made on the mandibular rim at the occlusal vertical dimension. The posterior extent of the mandibular rim is relieved 1 mm. Orientation notches are placed in both rims, and centric relation is recorded with a fast-setting vinyl polysiloxane material. (J Prosthet Dent 2001;85:621-3.)

A technique for border molding edentulous impressions using vinyl polysiloxane material.

A technique for making selective tissue placement final impressions for complete dentures using vinyl polysiloxane and custom trays with peripheral relief is presented. This technique is an alternative to the conventional method of border molding using modeling plastic impression compound.

The results of a brief survey of complete denture prosthodontic techniques in predoctoral programs in North American dental schools.

A brief mail survey of North American dental schools was undertaken to ascertain the current techniques in complete denture prosthodontics regarding preliminary and final impressions, record bases, and denture teeth. Of the 64 schools surveyed, 54 responded (84%). Seventy-four percent of the respondents used only irreversible hydrocolloid (alginate) for their preliminary impressions; 15% used only modeling plastic impression compound. Eighty-one percent used only modeling plastic impression compound for border molding of the final impression tray; 7% used only polyether impression material. Forty-eight percent used only polysulfide rubber (PR) impression material for their final impression material; 4% used only polyether impression material. Only 1 school still used shellac as one of its materials for record bases. Thirty-five percent used only Triad; 35% used only acrylic resin; 24% used both of these materials. Thirteen percent of responding schools used only nonanatomic teeth. The majority (54%) used all three options (nonanatomic, semianatomic, and anatomic). Eleven percent used lingualized occlusion. As compared with a survey performed in 1985, the use of irreversible hydrocolloid as a preliminary impression material, the use of visible light-cured resins for record bases, and the use of anatomic teeth have increased. The use of plastic impression compound for border molding and PR as the final impression material has largely remained the same.