• The Journal of Advanced Prosthodontics
• /
• 제4권2호
• /
• pp.76-83
• /
• 2012

PURPOSE. Zirconia has been used in clinical dentistry for approximately a decade, and there have been several reports regarding the clinical performance and survival rates of zirconia-based restorations. The aim of this article was to review the literatures published from 2000 to 2010 regarding the clinical performance and the causes of failure of zirconia fixed partial dentures (FPDs). MATERIALS AND METHODS. An electronic search of English peer-reviewed dental literatures was performed through PubMed to obtain all the clinical studies focused on the performance of the zirconia FPDs. The electronic search was supplemented by manual searching through the references of the selected articles for possible inclusion of some articles. Randomized controlled clinical trials, longitudinal prospective and retrospective cohort studies were the focuses of this review. Articles that did not focus on the restoration of teeth using zirconia-based restorations were excluded from this review. RESULTS. There have been three studies for the study of zirconia single crowns. The clinical outcome was satisfactory (acceptable) according to the CDA evaluation. There have been 14 studies for the study of zirconia FPDs. The survival rates of zirconia anterior and posterior FPDs ranged between 73.9% - 100% after 2 - 5 years. The causes of failure were veneer fracture, ceramic core fracture, abutment tooth fracture, secondary caries, and restoration dislodgment. CONCLUSION. The overall performance of zirconia FPDs was satisfactory according to either USPHS criteria or CDA evaluations. Fracture resistance of core and veneering ceramics, bonding between core and veneering materials, and marginal discrepancy of zirconia-based restorations were discussed as the causes of failure. Because of its repeated occurrence in many studies, future researches are essentially required to clarify this problem and to reduce the fracture incident.

• The Journal of Advanced Prosthodontics
• /
• 제6권2호
• /
• pp.115-120
• /
• 2014

PURPOSE. The aim of this in vitro study was to evaluate the effect of aging on the tear strength and cytotoxicity of four soft denture lining materials. MATERIALS AND METHODS. Four commonly used soft denture lining materials, (Coe-Comfort$^{TM}$ GC America Inc., Alsip, IL, USA; Coe-SOFT$^{TM}$ GC America Inc., Alsip, IL, USA; Visco-gel Dentsply Caulk Milford, DE, USA; and Sofreliner Tough M Tokuyama Dental Corporation Tokyo, Japan) were selected. Sixty trouser-leg designed specimens per lining material were fabricated using a stainless steel mold for tear strength testing. The specimens were divided into non-thermocycling and 1000-, and 3000-thermocycling groups. For the cytotoxicity test, twenty-four disk shaped specimens per material were fabricated using a stainless steel mold. The specimens were soaked in normal saline solution for 24 h, 48 h and 72 h. Cytotoxicity was measured by XTT assay in L929 mouse fibroblasts. Data were analyzed by two way analysis of variance and Dunnett's test (P<.05). RESULTS. Before thermocycling, Sofreliner Tough M ($10.36{\pm}1.00N$) had the highest tear strength value while Coe-Comfort$^{TM}$ ($0.46{\pm}0.10N$) had the lowest. After 3000 cycles, Sofreliner Tough M ($9.65{\pm}1.66N$) presented the highest value and Coe-Comfort$^{TM}$ ($0.42{\pm}0.08N$) the lowest. Sofreliner Tough M, in all incubation periods was the least toxic with significant differences compared to all other materials (P<.05). Coe-Comfort$^{TM}$, Coe-$SOFT^{TM}$, and Sofreliner Tough M did not show any significant differences within their material group for all incubation periods. CONCLUSION. This in vitro study revealed that aging can affect both the tear strength and cytotoxicity of soft denture materials depending on the composition.

• Restorative Dentistry and Endodontics
• /
• 제10권1호
• /
• pp.115-126
• /
• 1984

The purpose of this study was to determine the incidence and the degree of interappointment pain and post obturation pain associated with the pretreated clinical factors or conditions, and to examine the correlation between the success or failure and the pretreated clinical factors or conditions and postoperative pain. The author experienced the conventional root canal therapy in one hundred fifty-one teeth after recording the following clinical factors or conditions - sex, age, pulp vitality status, presence or absence of periapical rarefaction, single or multirooted teeth, pretreatment pain, and investigated the pain during and after treatment for seven days. After six months all the cases were re-evaluated through the clinical sign, symptom, and the recalled radiograph. The following results were obtained; 1. Of the 151 teeth (73.5%) had no interappointment pain, 31 teeth (20.5%) slight pain; and 9 teeth (6.0%) moderate to severe pain. 2. The presence of the pretreatment pain significantly increased the incidence and degree of interappointment, and there were no significant relationship between interappointment pain and other clinical factors or conditions. 3. Of the 151 teeth, 142 teeth (4.0%) experienced no post obturation pain, 3 teeth (2.0%) slight pain, 6 teeth (4.0%) moderate to severe pain. 4. There were no statistical correlation between postobturation pain and any of the clinical factor or conditions. 5. 141 teeth (3.4%) of 151 teeth were evaluated as success in this study, and success rate was decreased significantly in the cases of periapical rarefaction before treatment and postobturation pain. But there were no significant relationship between success or failure and other clinical factors or conditions.

• Journal of Periodontal and Implant Science
• /
• 제25권2호
• /
• pp.290-300
• /
• 1995

Tooth mobility is one of the most important clinical parameters in examination, diagnosis, prognosis and treatment planning procedure. In order to determine the differences of tooth mobility according to radiographical bone level, clinical root length, clinical crown/root ratio, and bleeding on probing, 90 male adults with periodontal disease and 10 male adults with periodontal health($25{\sim}45$ years old) were selected through clinical examinations including occlusal relationship, probing depth, attachment level, and bleeding on probing. On the mandibular anterior teeth, standard periapical radiographs were taken, and tooth mobility was measured by Periotest(Siemens Co., Germany). The radiographic bone level of individual tooth was evaluated as coronal 1/3, middle 1/3, and apical 1/3 to anatomical root length, and clinical crown length from incisal edge to bone level and clinical root length from bone level to root apex were measured with Boley gauge, and subsquently clinical crown/root ratio was calculated. The difference of tooth mobility(Periotest value) according to radiographical bone level, clinical root length, clinical crown/root ratio, and bleeding on probing was statistically analyzed by unpaired Student t-test. Tooth mobility was significantly higher in bleeding group than non-bleeding group on probing in the teeth radiographic bone level of middle 1/3, with clinical root length longer than 6mm, and with clinical crown/root ratio over 0.3(p<0.01). But there was no statistical difference in tooth mobility between bleeding group and non-bleeding group on probing in the teeth with radiographic bone level of apical 1/3, with short clinical root length less than 5mm, and with clinical crown/root ratio under 0.2(p>0.05). The results note that the tooth mobility depends on clinical root length, clinical crown/root ratio and gingival inflammation, and in the teeth with relatively good alveolar bone support gingival inflammation is one of the most important factors that affect tooth mobility.

• 대한치과의사협회지
• /
• 제57권3호
• /
• pp.169-174
• /
• 2019

The rapid evolution of CAD/CAM (Computer Aided Design / Computer Aided Manufacture) led to a dramatic impact on all disciplines of dentistry especially in the fields of prosthodontics and restorative dentistry. This article is to examine the history, advantages & disadvantages and some clinical considerations of CAD/CAM restoration.

• 대한치과의사협회지
• /
• 제25권5호통권216호
• /
• pp.495-500
• /
• 1987

• Journal of Periodontal and Implant Science
• /
• 제50권1호
• /
• pp.1-1
• /
• 2020

• 대한치과보존학회:학술대회논문집
• /
• 대한치과보존학회 2007년도 Spring Scientific Meeting(the 127th) of Korean Academy if Conservative Dentistry
• /
• pp.294-294
• /
• 2007

• 대한치주과학회:학술대회논문집
• /
• 대한치주과학회 2009년도 춘계학술대회
• /
• pp.37-37
• /
• 2009

• 대한치과의사협회지
• /
• 제22권10호통권185호
• /
• pp.879-886
• /
• 1984