• The Journal of Korean Academy of Prosthodontics
• /
• v.39 no.1
• /
• pp.58-70
• /
• 2001

For the successful treatment of complete denture, obtaining a good retention is essential. There are lots of factors affecting denture retention. Denture material, one of those factors affecting denture retention, was the subject of this study, and internal surface treatment also considered for the method of enhancing denture retention. Two resin(Lucitone $199^{(R)}$(heat cured resin) Vertex $CP^{(R)}$(self cured resin)) and two metal($Biosil^{(R)}$(Co-Cr alloy), $Vitallium^{(R)}$(Co-Cr alloy)) denture base materials were used for making test denture base. Newly developed device was used for measuring denture retention. After the retention was measured. We treated internal surface of test denture base with $50{\mu}m\;Al_2O_3$ powder, under 90psi, for 1 minute. Then the retention was measured again. The result was analyzed with K-S test, one-way ANOVA test and independent t-test to deter mine the significant differences as the 95% level of confidence. The results are as follows : In cases of without internal surface treatment, the retention was increased in order of $Vitallium^{(R)},\;Biosil^{(R)},\;Vertex CP^{(R)}$ and Lucitone $199^{(R)}$. Except between Vertex $CP^{(R)}$ and $Biosil^{(R)}$, retention of the other materials was significantly different (p<0.05). After the treatment of internal surface, the retention was increased in order of $Vitallium^{(R)},\;Biosil^{(R)},\;Lucno\;199^{(R)},\;Vertex\;CP^{(R)}$. Except between Lucitone $199^{(R)}$ and Vertex $CP^{(R)}$, $Vitallium^{(R)}$ and $Biosil^{(R)}$ the retention of remaining groups was significantly different each other (p<0.05). In the matter of each material, after the internal surface treatment the retention was increased with Vertex $CP^{(R)},\;Biosil^{(R)}\;and\;Vitallium^{(R)}$ and the value of differences were statistically significant. When we compare the retention of resin and metal denture base, the retention of both denture bases increased significantly with internal surface treatment, and resin denture base showed better retention. As the results show, selecting denture base material could be an important choice of complete denture treatment. To increase denture retention, internal surface treatment can be considered as a possible method.

• The Journal of Korean Academy of Prosthodontics
• /
• v.57 no.4
• /
• pp.389-396
• /
• 2019

In patients with severely resorbed alveolar bone, it is difficult to gain retention in denture. Lack of retention makes denture unstable and lead to trouble in using denture. Suction denture seals the entire denture border with movable mucosa and this sealing mechanism forms negative pressure beneath the denture and produce higher retention and stability to denture. In this case, 4 edentulous patients visited for lack of retention with dentures. Considering their high expectation with retention, suction denture concept was used to fabricate retentive and stable denture. The purpose of this case report is to compare and analyze the considerations of suction denture restorations in edentulous patients.

• The Journal of Korean Academy of Prosthodontics
• /
• v.9 no.1
• /
• pp.79-83
• /
• 1969

1) 가능(可能)한한 조직(組織)이 변형(變形)되지 않아야 한다. 2) Atmospheric pressure를 이용(利用)하기 위(爲)하여 peripheral border 에 있어서의 조직변형(組織變形)이 필요(必要)한 경과(境過)는 그 정도(程度)가 eiastic force가 retentive force 보다 크지 않도록 최소한(最小限)으로 해야 한다. 3) Denture base와 조직(組織)의 원형간(原形間)에는 접촉(接觸)이 밀접(密接)해야 한다. 그래야 saliva의 film 균일(均一)하고 얇게 될 수 있다. 4) Atmospheric pressure는 denture의 retention과 중요(重要)한 연관성이 있으므로 physiologic seal area를 형성(形成)해 주는 것이 유리(有利)하다. 5) Ridge의 형태(形態)도 denture의 retention 대(對)한 하나의 중요(重要)한 인자(因子)이다. 6) Denture에 의(依)해서 피개(被蓋)되는 면적(面積)은 retention에 관계(關係)되는 한 인자(因子)로써 피개면적(被蓋面積)이 클수록 유지력(維持力)이 커진다. 7) Saliva의 viscosity도 retention의 한 인자(因子)가 된다. 8) Friction은 retention의 한 인자(因子)가 될수는 있으나 병인적(病因的)인 증상(症狀)을 유발(誘發)할수 있으므로 이용(利用)해서는 않된다.

• The Journal of the Korean dental association
• /
• v.12 no.9
• /
• pp.667-677
• /
• 1974

A testing machine was devised and constructed for the purpose of measuring the retentive forces of maxillary complete denture bases in subjects. Forth complete denture bases were made for ten subjects with three different denture base materials, following the usual denture construction technique. Retentive forces of the forty dentures were determined at seven locations. The tests on each base were repeated three times at intervals of 5 minutes. Differences in retention values were evaluated statistically. 1) Differences in retention values were found by the differences of the denture base materials, but acrylic resin was similar to chromium cobalt alloy. 2) The chromium cobalt alloy and acrylic resin bases from master models revealed the best retention values, the gold alloy base from master model was the poor second and the acrylic resin base from snap model was the third. 3) The retention values for hook-1 revealed higher than that for hook-2 and the retention values for hook-3 revealed the lowest value.

• The Journal of Korean Academy of Prosthodontics
• /
• v.22 no.1
• /
• pp.23-32
• /
• 1984

The effects between preexisting four types and one that author had designed of posterior palatal seal on the retention of denture base were compared and observed from six systemically healthy edentulous subjects. Using one without posterior palatal seal as the control, the retention of each type was measured and analyzed six times with cantilever type Load cell after adaptation of denture base, which were constructed with usual manner. The following results wear obtained. 1. Morphological and positional changes of posterior palatal seal effected on denture retention. 2. No specific type showed most desirable effect in every experimental subject. 3. Experimental subject I, II, VI showed higher retention on the control in every type. 4. In five types of posterior palatal seal, for subject III, VI F types and for subject II, V C types were most effective. 5. In each experimental subject F type showed higher retention than the control.

• The Journal of Korean Academy of Prosthodontics
• /
• v.48 no.2
• /
• pp.87-93
• /
• 2010

Purpose: The purpose of this study was to compare the retention of the two denture adhesives with a silicone edentulous model and a resin denture base in vitro study. Material and methods: The experimental groups were used two denture adhesives and classified into 5 subgroups each. Subgroups were divided by the number of times the saliva sprayed. The control group was used synthetic saliva only. Dislodging tensile strengths were applied to the resin denture base using Instron in 3 directions ; vertical, lateral, and anterior-posterior. Results: The retention of two denture adhesives was increased significantly than saliva alone (P <.05). In each denture adhesives, the retention of saliva sprayed first was decreased than denture adhesive alone, but it didn't have significant differences. Whenever saliva sprayed repeated, the retention was decreased significantly than saliva sprayed first (P <.05). In each denture adhesives, vertical retentive force was highest than lateral and anterior-posterior retentive forces, and anterior-posterior retentive force was higher than lateral retentive force. This results were significantly different (P < .05). Significant differences of the retentive ability among two denture adhesives were not observed. Conclusion: From the results, use of the denture adhesives resulted in improved retentive ability of denture. Especially retentive force was highest in vertical direction.

• The Journal of Korean Academy of Prosthodontics
• /
• v.32 no.4
• /
• pp.515-525
• /
• 1994

Impression taking is a very important procedure in complete denture fabrication for reproduction of the tissue surface from which obtain retention and support of denture base. Therefore, we can not construct retentive denture without precise impression taking. Retention in complete denture can be obtained by the closest contact between denture base and underlying tissue, maximum coverage and proper displacement of the border tissue for peripheral sealing. Therefore, it is very important to take impression of the border tissue displaced properly. Nowadays, impression of the border tissue is mainly taken by the border molding techniques by means of manual muscle trimming, but due to various muscle trimming methods as clinicians, it is difficult to select proper method. This technique is also bodersome to do and time-consuming procedure. Retention is also likely reduced, because of the recording excessive muscle movement than actural physiological border tissue movement. Therefore, the impression technique that records actual physiologic functional muscle movement is helpful to increase denture retention and easy to do. We named this technique a functional border molding technique. This technique is originally introduced by D. J. Neill and R. I. Nairn in 1968. We tried to fabricate complete denture by the impression by means of functional border molding technique for better retention and the convenience, and obtained good results.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.17 no.2
• /
• pp.107-112
• /
• 2001

The prosthodontic treatment of severely resorbed edentulous patients has been one of the frustrating areas due to extensive loss of tissues. The integrated neuromuscular balance among tongue, lip, and cheek is compromised. The retention, stability, and support are the three major factors to influence the clinical outcome. Fish described a denture as having three surface, with each surface playing an independent and important role in the over all fit, stability, and comfort of the denture. He recommended that the polished surface should be a series of inclines so that pressure from muscular activity will retain dentures. Within the denture space there is an area that has been termed the neutral zone. The neutral zone is that area in the mouth where, during function, the forces of the tongue pressing outward are neutralized by the forces of the cheeks and lips pressing inward. According to Jacobson and Krol, neuromuscular control interacts to provide retention and the relationship of polished surface of denture base to the surrounding muscular structure of orofacial capsule facilitates the stability and retention. This neutral zone concept has been demonstrated with various modification by a number of authors. The theory used to develop the denture base contours is based on the belief that the muscle should functionally mold not only the border but the entire polished surface. Lott and Walsh reported the clinical success on complete mandibular dentures with application of neutral zone concept. A number of studies demonstrated that denture stability and retention are more dependent on correct position of the teeth and correct contour of external surfaces of the denture in a severely resorbed alveolar ridge. This article presents a prosthodontic approach to treatment of a edentulous patient using neutral zone technique to improve the retention and stability of the prosthesis.

• The Journal of Korean Academy of Prosthodontics
• /
• v.33 no.3
• /
• pp.440-452
• /
• 1995

A success of complete denture prosthesis can be determined by the satisfaction degree of the dentist and the patient. There are many factors influencing on the satisfaction of the complete denture patients. The purpose of this study is to analyze the correlation between the masticatory satisfaction and clinical evaluation, and the speech satisfaction and clinical evaluation in complete denture patients. 79 patients(total 119 complete dentures) were examined in this study who were treated in Seoul National University Dental Hospital. Through clinical evaluation, 2 examiners evaluated sex, age, edentulous period, the years of having used present complete denture, the number of the previous dentures, the state of the opposite arch, retention, stability, support, occlusion, vertical dimension of the complete denture and the condition of the residual alveolar ridge. Through questionnaires concerned with mastication and speech, examiners evaluate the satisfaction degree of the patients. This study led to the conclusion that : 1. The satisfaction degree of the mastication was lower in older patients(p<0.001) and in patients whose present complete denture period was shorter(p<0.05). The satisfaction degree of the mastication in male was higher than in female patients(p<0.01). 2. The satisfaction degree of the mastication was high when the retention of the complete denture was good(p<0.05), and when the condition of the residual alveolar ridge was good(p<0.05). 3. The satisfacion degree of the speech was high when the retention of the complete denture was good(p<0.01). 4. The satisfaction degree of the mastication was higher in patients with upper and lower complete denture than in patients with single complete denture whose oppsite arch was unilateral partial denture(p<0.05).

• Journal of Dental Rehabilitation and Applied Science
• /
• v.28 no.2
• /
• pp.163-169
• /
• 2012

Denture adhesive is the material using for enhancing retention and function of the denture. For a long time, denture adhesive was regarded as a repulsive material for dentist. However, it seems that the needs for using this is increasing. This study was planned to recognize the denture adhesive about kinds, components, and action mechanisms through literature review, and also evaluate its clinical effects and implications.