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.

Dental professions recommend that mandibular impacted third molar be extracted for the prevention of osteomyelities crneoplasm or for the treatment of halitosis. Even the possibility of emergence of unexpected halitosis after the preventive extraction exists, there are few studies describing the unexpected halitosis. This study intended to measure the emergence of halitosis after extraction of mandibular impacted third molar. Thirty-eight patients who visited Daejin Medical Center participated in this study. Halitosis was objectively measured using Halimeter in 3 intervals-before, after I day, after 7 days. Third factors, scaling and gender, which may influence the halitosis were analyzed with stratification. This study finds that in general halitosis decreased after 1 day but increased after 7 days. Scaling was helpful in decreasing halitosis and women have less severe halitosis than men. The effects of time interval(p<0.05), gender(p=0.836), and scaling(p=0.7929) on the severity of halitosis were not statistically significant. However, since this study's patients are neither a representative sample nor a random sample, all data interpretation was focused on clinical significance instead of conventional statistical significance. Clinical significance of this study's findings are: 1) scaling should be conducted in advance, 2) men should be notified of the higher possibility of halitosis.

The purpose of this study is to report a clinical case of a patient whose vertical dimension of occlusion was lost. There are many reasons for the loss of vertical dimension and one of those can be a tooth wear problem. Thus in this article we will review shortly types of tooth wear: attrition, abrasion, and erosior. And layour the basic philosophy and principles in regaining the esthetics and function of a patient's oral condition with a history of psychological wear, through full mouth restorations.