• The Journal of Korean Academy of Prosthodontics
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• v.34 no.2
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• pp.373-383
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• 1996

In order to compare the accuracy of impression method using addition silicone putty impression material, metal master die was fabricated with 4 cylindrical abutments that were similar in shape to mandibular arch. Among the 4 abutments, two(A, D) with 8mm width and 7mm height were formed in the 2nd molar regions and the other two(B, C) with 6mm width and 7mm height were on the canine regions. Impressions were taken using one-step putty wash impression technique and two-step putty wash impression technique by three different types of impression materials(Perfect, Express, Exaflex). Upon measuring the distance between the abutments on the model by three dimensional measuring machine, the percent of devitaion of the materials were obtained, rendering the following results. The results obtained are as follows : 1. There was no significant difference in accuracy in regard with the impression method between one-step putty wash impression technique and two-step putty wash impression technique using addition silicone putty impression material. 2. There were no difference in accuracy among with three different addition silicone putty impression materials. 3. All the distances between abutments on improved stone models increased in comparison with those on the metal master model.

• Journal of Korean society of Dental Hygiene
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• v.1 no.2
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• pp.171-180
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• 2001

The purpose of this study was to compared with the properties of commercial polyvinyl siloxane impression materials on the Korean product and the other country one. The materials used in this study were 5 hydrophilic polvinyly siloxane impression materials of light body automixing type (Perfect-F, Handae Chemical, Korea; Examix, GC, Japan; Contrast, VOCO, Germany; Express, 3M, U.S.A; Extrude, Kerr, U.S.A.). Specimens of each impression material were fabricated from a mold with dimensions identical to that specified in ASTM D624-91 and were subjected to tensile lode at 500 mm/min until failure for tear strength. Properties of consistency, strain in compression, recovery from deformation, detail reproduction and linear dimensional change were tested according to the testing methods of the ISO specification no.4823(1992). From this study, the follow ing results were obtained 1. The tear strength values were high ET(3.4kN/m), EP(3.4kN/m), PF(3.0kN/m), CT(3.0kN/m), but the lowest was EM(2.2kN/m)(p<0.05). 2. In the consistency, CT(47 mm) had the highest value, followed by PF(42.1 mm), ET(41.2 mm), and EM(39.6 mm), EP(39.2 mm)(p<0.05). It means more flow that the consistency value is high. 3. The strain in compression values were high followed by EM(5.8%), PF(52%), CT(4.6%), ET(4.1%), EP(2.9%)(p<0.05). 4. In the recovery from deformation, ET(99.95%) and PF(99.90%) had the highest value, followed by EP(99.75%), EM(99.74%) without statistical signification, CT(99.64%) had the lowest value(p<0.05). 5. Detail reproduction reappeared to line $20{\mu}m$ all products. 6. The linear dimensional change was a little shrinked all products. and there were not statistical signification (p>0.05). All products were satisfied the ISO specification.

• Journal of Dental Rehabilitation and Applied Science
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• v.23 no.3
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• pp.239-248
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• 2007

The accuracy and dimensional stability of rubber impression materials are very important for the fitness of the final restoration. The purpose of this investigation was to evaluate the effects of the storage time and pouring frequency of the additional silicone materials on dimensional stability. Total 30 impressions were made of tooth prepared single crown. The dies had 1 buccolingual, 1 mesiodistal and 1 occlusogingival lines. Two additional silicone materials(examixfine, aquasil) were included. 15 specimens were made of each impression material and poured by type IV stone over times(1hour, 24hours, 72hours) after mixing. 5 impressions poured after 1 hour were used for second pouring after 24hours and third pouring after 72hours. The same examiner measured each specimen 3 times after lazer scanning. All statistical tests were performed with the level of significance set at 0.05. The results indicated that significant difference at any measuring point of stone dies except the buccolingual and mesiodistal lines of the specimen made at 1hour after mixing with examixfine when measurements at 1hour, 24hours and 72hours were campared. There were significant difference between two impression materials and at every measuring point of stone dies made at second and third pouring. The length of measuring point increased significantly as time passed by and increase of the pouring frequency. However, this results are clinically acceptable except the dies of the third pouring. Under the conditions of this study, the shrinkage rate of the additional silicone rubber impression materials significantly increased as time passed by and increase of the pouring frequency.

• The Journal of Korean Academy of Prosthodontics
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• v.54 no.4
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• pp.445-450
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• 2016

Piezography, prosthetic space recorded by pronunciation, can be used as a reference for arrangement of artificial teeth and polishing surface of a denture. In this case, a 67 year old female patient was presented for new dentures. Old dentures had class II relationship and poor retention. For fabrication of stable dentures, using piezography and lingualized occlusion was planned. After taking impressions with conventional method, conventional denture bases with wax rim were fabricated. Then, additional mandibular denture base was fabricated for piezography. With fast setting silicon impression material, piezography was recorded by using six pronunciations, 'si', 'so', 'me', 'te', 'de', and 'mu'. According to the piezographic space, mandibular artificial teeth were arranged and modified for lingualized occlusion. As a result, the patient was satisfied with new dentures functionally and esthetically.

• Journal of Dental Rehabilitation and Applied Science
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• v.39 no.3
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• pp.158-167
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• 2023

As digital technology has advanced in the field of dentistry, the use of computer-aided design/computer-aided manufacturing (CAD/CAM) has brought changes to the stages of dental treatment. The use of CAD/CAM technology in dental restoration offers clinical efficiency and convenience by reducing production time and appointment intervals, while also simplifying the fabrication process to reduce errors. In this case, digital replication and printing of temporary teeth were used to aid a patient with complex medical histories and physical disabilities. The final impression obtained with silicone impression material included information on the vertical dimension, centric relation, and the angle and length of the anterior teeth, which shortened the production time and appointment intervals and increased patient satisfaction. The final restoration was fabricated using milling and monolithic disc techniques, demonstrating appropriate stability, retention, and support, resulting in functional and aesthetic satisfaction.

• The Journal of the Korean dental association
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• v.41 no.1 s.404
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• pp.35-41
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• 2003

Wettability of addition silicone impression material is very important property for making an accurate restoration. This study examined theimpression quality in clinical condition and the wettability of impression material. Three commercially available addition silicone impression material (Imprint; 3M, USA, Examix; GC, Japan, Perfect; Handae, Korea) were studied. A total of 90 putty/wash impressions of semi-dried premolars and wet molar teeth were examined for void production in impression body. The percentae of the sulcus reproduction ability of each material was calculated from the sulcus depths of cross-sectioned casts from the impressions with stereomicroscope. Three impression materials were used to produce die stone casts from vcid entrapment die. Voids in the stone casts were counted with the stereomicroscpe. From the experiment, the following results were obtained: 1. In direct observation, Imprint showed greatest numbers of void in impression body (P<.001).However, correlations were not found between sulcus reproduction and void production. 2. Sulcus reproduction ability of additional silicone impression material was diminished in order of Imprint, Examix, Perfect. The significant difference was found between Imprint and other material (P<.001). 3. In void entrapment laboratory test, void productions was diminished in order of Examix, Imprint, Perfect. All voids in casts were less in delayed poured cast than immediately poured cast. 4. Especially, the stone pouring time of Perfect impression material should be delayed.

• The Journal of Korean Academy of Prosthodontics
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• v.30 no.2
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• pp.233-245
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• 1992

The purpose of this study was to evaluate the demensioal stability and wettability of several rubber impression materials. Impressions were made from a metal master die machined to stimulate five full veneer crown preparations symmetrically placed in an arch form. Cast from impressions were measured about ; 1) intrapreparation distance 2) lower base diameter 3) length. For comparing materials were formed against a smooth surface. The advancing contact angle of a saturated aqueous solution of $CaSO_4$ on the impression materials was measured after 1 minute. Mean contact angle were calculated and results were analyzed. Results were as follows : 1. As the intrapreparation distance, hydrophilic addition-cured silicone had the smallest change and condensation-cured silicone had the largest one. 2. As the lower base diameter, traditional addition-cured silicone had the smallest change and polyether had the largest one. 3. As the height, traditional addition-cured silicone had the smallest change and polyether had the largest one. 4. As the contact angle, polyether had the smallest change and condensation-cured silicone had the largest one.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.24 no.2
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• pp.371-379
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• 1994

본 연구는 비규격화시켜 촬영한 두장의 방사선 사진을 일반 영상처리 프로그램으로 기하학적 보정을 하여 디지탈 공제 촬영술을 시행한 결과를 개인별로 제작된 필름유지장치를 이용하여 규격화 시켜 촬영한 두장의 방사선사진을 디지탈 공제 촬영술을 시행한 결과와 비교하여 일반 영상처리 프로그램의 임상적 유용성을 평가해보고자 시행하였다. 19명의 자원자를 대상으로 하여, 각 환자에서 4매의 하악구치부 치근단 사진을 촬영하였다. 그중 2매는 XCP 필름 유지장치만으로 평행촬영법으로 촬영하였고, 나머지 2매는 교합제에 인상재를 부가하여 개인별로 제작된 XCP필름 유지장치를 이용하여 표준화시켜 역시 평행촬영법으로 촬영하였다. 기하학적 보정은 "Adobe Photoshop"과 "NIH Image" 프로그램으로 시행하였다. 특히 "Adobe Photoshop"의 임의영상회전 기능과 "IH Image"의 공제시술시 중첩된 사진을 투명하게 보여주는 기능, 병진기능을 활용하였다. 두 사진의 유사성을 측정하기 위해 공제된 사진의 계조도의 표준편차를 구하였다. 표준화군의 평균 표준편차가 기하학적 보정군의 평균 표준편차보다 약간 낮았으나, 통계적으로 유의성이 있는 차이를 보이지는 않았다. 위의 결과로 미루어보아, 하악구치부 에서 XCP필름 유지장치로 평행촬영한 비표준화방사선사진을 "Adobe Photoshop"과 "NIH Image" 프로그램을 이용하여 기하학적 보정을 할 수 있으리라 사료된다.

• The Journal of Korean Academy of Prosthodontics
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• v.31 no.2
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• pp.207-218
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• 1993

The purpose of this study was to evaluate the reproducing accuracy of stone casts made from complete arch impressions using different impression materials. The impression materials studied were 1) polyether, 2) polysulfide, 3) polyvinyl siloxane, and 4) irreversible hydrocolloid. Impressions were made from a partially edentulous acrylic resin model with metal inserts in canine, first molar region bilaterally and mid palatal vault region. Each distance between 2 out of 5 meauring points was measured by using 3dimensional measuring machine. Impressions were poured at once with a type IV dental stone. Data were analyzed using t-test with a sample size of six. The results were as follow : 1. Polysulfide and polyether were significantly superior to polyvinyl siloxane and irreversible hydrocolloid in reproducing full arch model(p<0.05), but there were no statistical differences in amount of dimensional reproducing accuracy for full arch impression between polysulfide and polyether(p>0.05). 2. There were statistical differences in amount of dimensional reproducing accuracy between edentulous area and tooth bound area for polysulfide and polyether(p<0.05). but no statistical differences were observed for polyvinyl siloxane and irreversible hydrocolloid(p>0.05).

• The Journal of Korean Academy of Prosthodontics
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• v.37 no.1
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• pp.134-138
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• 1999

연구개는 그 주위조직과 더불어 생리적 기능에 있어 음성, 연하, 및 호흡 등에 중요한 역할을 한다. 종양등의 이유로 인한 연구개의 외과적 절제는 그 해부학적 크기와 모양의 영구적인 변화로 인해 여러기능의 상실을 초래한다. 이에 따른 결함은 과도한 비음, 연하중 음식물이나 유동물의 비관으로의 누출 등을 들 수 있다. 연구개와 그 주위조직의 생리적인 기능의 숙지 및 이를 응용한 보철물(Palatopharyngeal Obturator)의 적절한 제작은 이러한 기능적 결함을 수복하는데 이용되어진다. 본 증례에서는 종양으로 인해 연구개를 절제한 환자의 보철적 수복에 있어, 구강내 온도에 따라 그 형상이 변화하는 인상재를 이용하여, 측-후 인두벽의 운동을 기능적으로 인기하는 방법을 이용하였다. 이러한 방법으로 제작된 보철물은 종양으로 인한 연구개의 절제 후 생리적인 기능의 장애를, 올바른 Palatopharyngeal 폐쇠를 유도함으로써 음질의 향상, 연하등의 기능을 회복시키는데 큰 도움이 될 수 있음을 보여준다.