Comparison of Vertical Magnification Ratio among Various Areas in Panoramic Radiographs

PURPOSE: The objective of the present article is to determine whether there are differences in vertical enlargement ratio among various sites within both jaws in a panoramic radiograph. MATERIALS AND METHODS: Two hundred and seventy-threeimplant sites in panoramic radiographs were evaluated by two observers. Magnification ratios at various sites in both jaws were calculated and compared with each other. RESULT: The average vertical enlargement ratio in the panoramic radiograph was 1.264 and this value was larger than original ratio 1.250. Although vertical magnification ratio of maxillary molar area was higher than that of mandibular molar area, every group showed similar magnification ratio in clinical respect. CONCLUSION: Vertical magnification ratio of the maxillary molar area is statistically higher than that of the mandibular molar area in the panoramic radiograph, but it is clinically negligible.

Relationship between The Shape of Palatal Vault and Tooth and The Thickness of Palatal Masticatory Mucosa / 대한치주과학회지

The aim of present investigation was to clinically measure the thickness of palatal masticatory mucosa in the hard palate as potential donor site for mucogingival surgery, to determine the relation to shape of palatal vault, form of tooth, gender, and to serve the clinical criteria to choose the proper surgical technique. 84(mean age:25yrs) systemically and periodontally healthy volunteers participated in this study and 18 standard measurement points were defined in the hard palate, located on 3 lines which ran at different distances parallel to the gingival margin. 6 positions were designated on each of these 3 lines between the level of canine and 2nd molar and a bone sounding technique using a periodontal probe with minimal local anesthesia was utilized to assess the thickness of palatal masticatory mucosa. Student t-test was used to determine the difference in mucosal thickness between 2 groups gender, shape of palatal vault (high palatal vault vs. low palatal vault), tooth form (short-wide vs. long narrow) The result of this study were as follows: 1. Soft tissue thickness progressively increased in sites further away from the gingival margin (p<0.01). 2. Depending on position, in line a and line c the masticatory mucosal thickness increased from Ca to M2(p<0.01), but in line b the thickness increased from Ca to P2, and decreased to M1 and increased again to M2. 3. Gender did not influence the thickness of masticatory mucosa. 4. Palatal vault shape was associated with the thickness of masticatory mucosa. Thickness of low palatal vault group was thicker than high palatal group between P2 and M2 position. 5. Form of tooth did not influence the thickness of masticatory mucosa. In conclusion, palatal vault shape was associated with the thickness of masticatory mucosa. So, mucogingival surgery can be considered as a treatment modality in high palatal vault group. But, Gender and tooth form did not influence the thickness of masticatory mucosa.