Mayada F.doc J Bagh College Dentistry Vol. 25(4), December 2013 Evaluation of tissue Restorative Dentistry 17 Evaluation of tissue displacement in posterior palatal seal area with different impression techniques with varying palatal forms Mayada Q. Abdul Khafoor, B.D.S., M.Sc. (1) Rafah A. Ibrahim, B.D.S., M.Sc. (2) Ilham H. Al-abdulla, B.D.S., M.Sc. (3) ABSTRACT Background: This study was designed to measure the displacement pattern of posterior palatal seal (pps) area in different forms of the palate and with different impression techniques. Materials and method: This study was used to measure the displacement pattern of (pps)in different palatal shapes by using different impression materials Korrecta wax No.4,Green compound and design of House for pps for each palatal forms by using a 3D Scanner of CAD/CAM and measuring the distance between 2 points in pps area by using Caural Threw. Result: The results show highly significant differences between these techniques and the control group (impression with light body) Conclusion: The physiological impression technique of pps with Korecta wax no.4 and design of House for each palatal forms give less displacement than the physiological impression with green compound. Keywords: Maxillary complete dentures, posterior palatal seal. (J Bagh Coll Dentistry 2013; 25(4):17-25). INTRODUCTION The security of maxillary complete denture depends primarily on close peripheral contact between the denture and its supporting tissue. 1 The pps area has been defined as an area that is located at the junction of hard and soft palate and which is composed of a soft tissue, along which pressure will be applied by a denture, within the physiological limits of the tissue, to aid in denture retention2. A well fitting and retentive maxillary complete denture requires : a well fitting surface, a peripheral border compatible with the muscles and tissues which make up the muco-buccal and muco-labial space, so that a peripheral seal is created by soft tissues draping over them and finally by a pps3 . Brian and Robert discussed different materials for achieving a PPS of a maxillary complete denture which include arbitrary scraping of the cast prior to denture processing, the physiological impression technique and the selective pressure impression technique.4 Laney and Gonzales5 discussed the need for knowledge of the oral cavity anatomy so that the static surface of the denture base can be balanced against one dynamic tissue surface. In the pps area, the tissues are displaceable and the degree of displacement can be sensitized by palpation with “T” burnisher6, by closing both nostrils of the patient and make him blow gently7 (1)Assistant Professor, Department of Prosthodontics, College of Dentistry, University of Baghdad. (2)Lecturer, Department of Prosthodontics’, College of Dentistry, University of Baghdad. (3) Assistant Lecturer, Department of Prosthodontics, College of Dentistry, University of Kerbala. or by noticing the vibrating line when the patient says “ah” 8. The anterior and posterior vibrating lines are considered as two separate lines of flexion 9. Also by measuring the tissue with various impression materials, a functional or physiological pps can be made as early as the maxillary final impression10. The posterior border of the maxillary denture extends into and through the pterygo-maxillary notches and along the vibrating line. The pterygo- maxillary notch is bounded posteriorly by the hamular process of the sphenoid bone and the lateral pterygyoid plate and anteriorly by the maxillary tuberosity 11. The tensor palati muscle wraps around the hamular process and attaches to the posterior nasal spine to form the palatal aponeurosis12. The pterygo-mandibular ligament extends from the hamular process to the lingula of the mandible. Pendleton’s13 anatomic dissections and histological and clinical examination have shown this area to vary greatly in size, form and character. The shape of palatal vault is related to the activity of the soft palate .The flat vault has the least movable soft palate and the widest area of displaceable tissue. In contrast, the high vault or “V” shaped palate often has a soft palate virtually at right angles to the hard palate and is extremely mobile. Thus, the area of tissue displaceability is very narrow .The intermediate palatal vault lies between these two extremes so that House classified the palatal form to class I flat palatal vault in the hard palate and class III a high vault and class II intermediate between them14,15. Nikoukari16measured the dimension and J Bagh College Dentistry Vol. 25(4), December 2013 Evaluation of tissue Restorative Dentistry 18 displacement of pps in different palatal shapes, he used different impression materials and found that the tissue displacement caused by ZOE was less than that caused by other materials. This study was designed to detect the displacement pattern of pps in different palatal shapes with different impression techniques. MATERIALS AND METHODS A. Selection of patient: Twenty one (21) patients with different palatal form (deep, medium and flat), were selected visually by a team of prosthodontics to determine the palatal form , from Prosthodontic Clinic , College of Dentistry , University of Baghdad ,seven for each group. The age ranges between 60-70 years without any posterior under cut. B. Impression techniques: The primary impressions were made with alginate. Then impressions were poured with stone (zeta, selensor, industriazingardi, Italy) Three closed fit special tray and one spaced special tray were fabricated for different impression techniques. I. Final impression (control group) by using spaced special tray and taking impression with light body (elastic impression material ) ,then poured with stone .The cast considered as control was marked 1,as shown in fig (1). II. Physiological pps impression technique by using Korecta wax No.4 and another one by using low –fusing modeling compound with the following steps: 1. The posterior border of the special tray should be trimmed and adjusted one to two mm distal to the vibrating line. 2. Border molding should be done and the final impression was taken by using zinc oxide eugenol (ZOE) paste. 3. The vibrating line should be marked in the mouth with indelible pencil by asking the patient to say “ah” with nose blowing and using the fovea palatine in locating the vibrating line (anterior and posterior vibrating line) and transferring the location to the ZOE impression17. 4. Kerr Korecta wax No.4 and low fusing modeling compound were used to record the pps by painting it on pps area of impression. 5. The impression should be returned to patient mouth and held it in place for about 3 minutes. Patient is guided to tip its head forward to approximately 30o from the vertical position and place his tongue against tray handle 18-20. 6. Impression is removed and excess material removed with Bard-parker blades. Then impression is reseated for 5 to 8 minutes. 7. Impression is carefully beaded and boxed and poured with stone .These 2 castes were marked 2 with Korrecta wax and 3with modeling compound as shown in fig (2) and (3). III. Ordinary impression technique with ZOE 1. The same steps 1, 2 and 3 which were done in the previous technique are done here. 2. The impression then was poured with stone and the master cast was marked 4. 3. Scraping cast 4 for incorporation of pps to carve certain design by using No.4 round bur with lacron carver21 .The patients were classified (visually) into groups according to House’s classification of palatal form. Group A (deep palatal form) A1=control group with light body impression. A2=physiological impression of pps with Kerr Korrecta wax No.4 A3=physiological impression of pps with low – fusing molding compound. A4=scraping casts No.4 in pps area according to House- single bead 1mm depth and width22. Group B (intermediate palatal form) B1=control group with light body impression. B2= physiological impression of pps with Kerr Korrecta wax No.4 B3=physiological impression of pps with low – fusing molding compound. B4=scraping casts No.4in pps area according to House –modified butterfly 2-3mm wide and 1mm depth. Group C (Flat palatal form) C1=control group with light body impression. C2=physiological impression of pps with Kerr Korrecta wax No.4. C3=physiological impression of pps with low- fusing modeling compound. C4=scraping casts No.4 in pps area according to House –modified butterfly 3-4mm wide and 1mmdepth22. C. Preparing working casts I. On the working casts (No.1) indicate the incisive papilla and the position of fovea palatine on the midline, 1/3distance between these two points indicated as point 1 near fovea palatine on midline. Indicate the crest of hamular notch on the cast and put a point on the end of hamular notch on the ridge on both sides, which are indicated as points 3 and 7. J Bagh College Dentistry Vol. 25(4), December 2013 Evaluation of tissue Restorative Dentistry 19 Draw a straight line between points 3 and 7 and put point No.5 on the midline .Half the distance between point 3 and 5, put point 4. Half the distance between points 5 and 7 put point 6. Put a point on the location of fovea palatine on the midline indicate as point 9, draw a horizontal straight line from point 9 on the center of crest of ridge on both sides and indicated as points 2 and 8, half the distance between points 9 and 2, put point 10 ,half the distance between points 9 and 8, put point 11 . Also half the distance between points 9 and 10 put point 12 and half the distance between 9 and 11 put point 13 .These points 10, 11, 12, 13 are used to measure the depth of pps area .as shown in fig (4). II. A splint was made on the control casts No.1 by using cold cure acrylic23 (Ivoclar).fig (5), these points were transferred on the cast to the splint by indelible pencil and a hole was made on the splint by using round bur No.4. Then this splint was used on the other casts No.2, 3 and 4 and the location of these points should be transferred to the casts fig (6). III. For measuring the width of tissue displacement in pps area ,scanner of these casts should be made by using three dimension (Laser Denta) of CAD/CAM (Computer-Aided Design/Computer-Aided Manufacture) 3 dimension scanner to take a picture with its original dimensions of the casts as shown in Fig. (7 and 8) ,these pictures were directly evaluated and measured through data analyzed in the computer by using Caural Threw program to measure the distance between points 1-3, 1-4, 1-5, 1-6, and 1-7 and distance between points 2-9 and 8-9 to show the displacement pattern in post dam area for each impression technique in millimeters 24,25. IV. Measuring the depth of pps at different points. The acrylic splint which is used for transferring the points was put on the cast No. 1 (control) and pins were put on both sides of points 2 and 8 to fix the split on the cast. Then by using a pin like (reamer which is used for endodontic treatment) with stopper to determine the length of pins which were inserted inside points 10, 11, 12 and 13 to measure the depth of pps in this area and then should be measured by vernier .This procedure should be repeated on casts No. 2, 3 and 4 to measure the depth of pps for all the patients for each group as shown in fig 9. RESULTS 1. Measurement of width of pps area: Group A (deep palatal vault) The mean values, SD and ANOVA of the statistical analysis for the data of the distance between the 2 points for group A were shown in table 1. Whereas the result of LSD (multiple comparison) between the four groups (A1, A2, A3 and A4) were shown in table 2. The results show that there were highly significant differences in data between the groups A1, A2, A3 and A4 except for the data of distance 1-5 between A1 and A4 which show that there were non significant differences. The mean differences for each distance for group A2,A3 and A4 with the control A1 show that the least tissue displacement were in group A4 (design of House single bead )followed by A2 (physiological impression with Korecta wax)also show the least displacement while A3(low-fusing compound )which show more displacement. Group B (intermediate palatal vault). The mean values, SD and ANOVA of statistical analysis for the data of distance between 2 points for group B were shown in table 3.Whereas the result of LSD between the 4 groups B1, B2, B3 and B4 were shown in table 4. The results explained that there were very highly significant differences between the data of each group (B1, B2, B3 and B4). The mean differences for the data of each distance between the groups ( B2, B3, and B4) with the control group B1 show the least displacement were in groups B2 (Korrecta wax ) and B4 (design of House).While the most displacement was in group B3 (low-fusing compound ). Group C (Flat palatal vault) The mean values, SD and ANOVA of statistical analysis for the data of distance between 2 points for group C were shown in table 5. Whereas the result of LSD between the four groups is shown in table 6. The result explained that there were highly significant differences between the four groups C1, C2, C3 and C4 for each distance except that there was a non significant difference for data of distance 1-4 points between C2 and C3 groups. The mean difference between groups C2, C3 and C4 with C1 for the result shows that the least displacement were in groups C2 (Korrecta Wax) and C4 (design of House) and more displacement was in group C3 (Low-fusing Compound). 2. Measurements of the depth of points in pps area: Tables 7 , 8 , 9 , 10 , 11 and 12 give readings for deep , medium and flat palates respectively J Bagh College Dentistry Vol. 25(4), December 2013 Evaluation of tissue Restorative Dentistry 20 with ANOVA and LSD multiple comparison , Which show highly significant differences between these groups. The results indicated that the tissue displacement caused by elastic materials (control group) was less than that caused by other materials in all three types of palatal shape. The casts in which the pps area was obtained with modeling compound had the highest displacement readings; this result was found for all three types of palatal shapes; while the measurements obtained from Korecta Wax and design of House were between those readings of control group and modeling compound. DISCUSSION The pps area has been defined as an area that is located at the junction of hard and soft palat and which is composed of a soft tissue, along which pressure will be applied by a denture within the physiological limits of the tissue to aid in denture retention2. The results of all groups indicated that the tissue displacement caused by Kerr Korecta wax No.4 was less than the green compound tracing impression technique this due to the fact that this wax is a fluid and the mouth temperature wax is more preferable for this procedure .It flows sufficiently at mouth temperature to avoid displacement of tissues, and as the wax continues to exhibit its property of flow in the mouth ,it permits the tissues in the area of pps to rebound ,establishing a degree of displacement that is physiologically acceptable18 .This result agrees with Nikoukari 16.,who stated that casts in which the pps area obtained with modeling compound had a higher displacement than that obtained by Korrecta wax No.4. The scraping method according to House classification of palatal vault of pps for each group showed that the best result (the lowest displacement ) approximately nearer to the result of Kerr korecta wax .This result occurred because in group C (flat palatal vault )the vibrating line was further posteriorly, resulting in the broadest pps area ,so that the design of House is 3-4 mm butterfly .Where as in the deep vault ( group A), the posterior extension of pps area was less than in group B (medium vault )so the design of House in deep vault single bead is 1 mm in depth and width. This result agrees with the observation of Swenson and Terkla who observe that the direction of vibrating line differ with the shape of the palate .The higher the vault the more abrupt and forward is the vibrating line. In a mouth with a flat vault, the vibrating line is usually further posteriorly and has a gradual curvature affording a broader pps area 26,27. As conclusions; one of the most important problems that associated with poor retention of the maxillary complete denture is a faulty pps It can be concluded from this study the following: 1- The physiological impression with Korecta wax No.4 for pps area gives less tissue displacement than other materials. 2- The palatal form aids in the selection of the type of posterior palatal seal needed .The House design of pps for each type of palatal forms gives less displacement in this area. REFERENCES 1. Lamb DJ, Samara R, Johnson A. Palatal discrepancies and post dam. J Oral Rehabil 2005; 32:188-92 2. Ronald LE, Forrest RS. The posterior palatal seal .A review. Aust Dent J 1980; 25(4):197-200. 3. Avants WE. Comparison of the retention of complete denture bases having different types of posterior palatal seal. J Prosthet Dent 1973; 29(50): 484-93 4. Brain W, Robert F. Accurate location of Posterior palatal seal area on the maxillary complete denture cast. J Prosthet Dent 2006; 96(6): 454-5. 5. Laney WR, Gonzales JB. The maxillary denture: Its palatal relief and posterior palatal seal. J Am Dent Assoc 1967; 75: 1182-7. 6. Bylicky HS. Variable approaches in obtaining a posterior palatal seal: description of technique. NYJ Dent 1966; 36: 280-2. 7. Heart Well GM, Rhn AO. Syllabus of complete dentures. 1st ed. Philadelphia: Lea and Febiger publishers; 1968. 8. Hardy IR, Kapur KK. Posterior border seal, it’s rational and importance. J Prosthet Dent 1958; 8(3): 386-7. 9. Vernie AF, Chitrev, Aras M. A study to determine whether the anterior and posterior vibrating lines can be distinguished as two separate lines of flexion by unbiased observer: A pilot study. Indian J Dent Researcher 2008; 19(4): 335-9 [IVSL]. 10. House MM. Full dentures techniques study club No.1, 1950. 11. Edwards LF, Boucher CO. Anatomy of the mouth in relation to complete denture. JADA 1942; 29(3): 331- 43. 12. Boucher CO, Hickey JC, Zarb GA. Prosthetic treatment for edentulous patients. 11th ed. St. Louis. The C.V Mosby Company. 1997. pp.118-20. 13. Pendleton EC. Influence of biological factors in retention of artificial dentures. JADA 1936; 23(7): 1233-51. 14. Sudhakara VM, Sudhakara UM, Karthik KS, Vdita SM. A review on diagnosis and treatment planning for completely edentulous patients. JIADS 2010; 1(2):15- 22. 15. Watt DM, Mac Greagor AR. Designing complete dentures. Philadelphia: W.B. Saunders Company; 1976. pp. 83-6. 16. Nikoukari H. A study of posterior palatal seal with varying palatal forms. J Prosthet Dent 1975; 34: 605- 13. J Bagh College Dentistry Vol. 25(4), December 2013 Evaluation of tissue Restorative Dentistry 21 17. Behnoush R, Vicki CP. Current concept for determining the posterior palatal seal in complete denture. J Prosth Dent 2003; 12(4): 265-70. 18. Gerald SW. Establishing the posterior palatal seal during the final impression procedure: a functional approach. J Am Dent Assoc 1977; 94; 505-10. 19. Silverman SI. Dimension and displacement patterns of posterior palatal seal. J Prosth Dent 1971; 25: 470. 20. Aaron Yu-Jen and Terry E. Donovan.Engaging the physiological PPS with the frame work of a maxillary over denture. J Pros Dent 2009; 101: 214-5 21. Mohammed AA, et al. Comparing required dislodging forces between different types of posterior palatal seal. Must Dent J 2006; 3(1): 97-101. 22. Sudhakara VM, Karthik K.S. A review on posterior palatal seal. JIADS 2010; 1(1): 16-21. 23. Aljudy HJ. Measurement of the extension ridges tissue displacement on the cast obtained from various impression techniques. College of Dentistry – University of Baghdad 2001. 24. Reem A. Surface area measurement of upper dental arch with different final impressions. J Bagh Coll Dentistry 2013; 25(2): 36-41. 25. Andrea E, Albert M. Accuracy of complete – Arch dental impressions: A new method of measuring trueness and precision. J.P.D 2013; 109: 121-8. 26. Swenson MG, TerklaL G. Complete denture. 6th ed. St. Louis: the C.V. Mosby company: 1970. pp. 65-70, 372-6. 27. Mayada Q. A comparison of the retention of complete denture base having different types of posterior palatal seal with different palatal forms. J Bagh Coll Dentistry 2012; 24(2): 11-5. Table 1: Means, standard deviation (SD) and ANOVA of each distance between 2 points of group A (deep palatal vault) width of pps in (mm) Distance between 2 points A1 Control A2 Korrectawa A3 Tracing compound A4 Single bead Sig. Mean SD Mean SD Mean SD Mean SD 1-3 31.21 .0283 32.68 .01582 33.6 .00708 32.3 .0079 .000 1-4 27.24 .01225 30.2 .0083 31.1 .01581 29.25 .0077 .000 1-5 22.86 .0100 23.18 .00707 23.6 .01581 22.86 .0592 .000 1-6 27.24 .0173 32.95 .00707 33.3 .01582 28.24 .01732 .000 1-7 31.84 .0100 33.52 .01581 34.56 .0083 32.82 .0158 .000 9-2 21.6 .0123 24.0 .012 24.3 .0273 22.78 .00708 .000 9-8 22.0 .0255 24.53 .00707 24.63 .02236 23.11 .01000 .000 Table 2: LSD multiple comparisons between the groups of each distance between 2 points for group A( for width of pps ) Groups 1-3 1-4 1-5 1-6 1-7 9-2 9-8 Mean diff sig Mean diff sig Mean diff Sig Mean diff sig Mean diff sig Mean diff Sig Mean diff Sig A1 A2 -1.47 .000 -2.96 .000 -.32 .000 -5.71 .000 -1.68 .000 -2.4 .000 -2.53 .000 A1 A3 -2.39 .000 -3.86 .000 -.74 .000 -6.06 .000 -2.72 .000 -2.7 .000 -2.63 .000 A1 A4 -1.09 .000 -2.01 .000 .00 1.00 -1.0 .000 -.98 .000 -1.18 .000 -1.11 .000 A2 A3 -.92 .000 -.90 .000 -.42 .000 -.35 .000 -1.04 .000 -.30 .000 -.10 .000 A2 A4 .38 .000 .95 .000 .320 .000 4.71 .000 .70 .000 1.22 .000 1.42 .000 A3 A4 1.3 .000 1.85 .000 .74 .000 5.06 .000 1.74 .000 1.52 .000 1.52 .000 The mean differences are significant at the .05 level Table 3: Means, standard deviation (SD) and ANOVA of each distance between 2 points of group B (intermediate palatal vault) width of pps in (mm) Distance between 2 points B 1 control B2 Korrecta wax B3 Tracing compound B4 Butterfly 2-3mm Sig. Mean SD Mean SD Mean SD Mean SD 1-3 30.68 .0282 31.1 .1000 32.66 .01581 30.9 .00707 .000 1-4 23.4 .00707 23.85 .03803 23.95 .0308 24.12 .0187 .000 1-5 18.22 .0158 18.44 .0169 19.02 .01000 18.32 .00707 .000 1-6 23.38 .0173 23.6 .00707 23.95 .01581 24.12 .01581 .000 1-7 30.56 .010101 31.32 .0123 31.93 .01225 30.77 .0123 .000 9-2 22.11 .01225 24.08 .01581 24.98 .00837 23.02 .01000 .000 9-8 24.23 .0255 26.2 .00707 26.45 .02236 25.99 .01000 .000 J Bagh College Dentistry Vol. 25(4), December 2013 Evaluation of tissue Restorative Dentistry 22 Table 4: LSD multiple comparisons between the groups of each distance between 2 points for group B (for width of pps in (mm)) Groups 1-3 1-4 1-5 1-6 1-7 2-9 9-8 Mean diff sig Mean diff sig Mean diff sig Mean diff sig Mean diff sig Mean diff Sig Mean diff Sig B1 B2 -.42 .000 -.45 .000 -.22 .000 -.22 .000 -.76 .000 -1.97 .000 -1.97 .000 B1 B3 -1.98 .000 -.55 .000 -.80 .000 -.57 .000 -1.37 .000 -2.87 .000 -2.22 .000 B1 B4 -.22 .000 -.72 .000 -.10 .000 -.74 .000 -.21 .000 -.91 .000 -1.76 .000 B2 B3 -1.56 .000 -.10 .000 -.58 .000 -.35 .000 -.61 .000 -.902 .000 -.25 .000 B2 B4 .20 .000 -.27 .000 .12 .000 -.52 .000 .55 .000 1.06 .000 .21 .000 B3 B4 1.76 .000 -.17 .000 .70 .000 -.17 .000 1.16 .000 1.962 .000 .46 .000 The mean difference is significant at the .05 level. Table 5: Means, standard deviation (SD) and ANOVA of each distance between 2 points of group C (flat palatal vault ) for width of pps in (mm) Distance between 2 points C 1 control C2 Korrecta wax C3 Tracing compound C4 Butterfly 3-4mm Sig. Mean SD Mean SD Mean SD Mean SD 1-3 33.38 .01581 34.28 .01581 35.06 .02074 33.98 .01225 .000 1-4 25.1 .07071 26.74 .03162 26.78 .01581 26.57 .05148 .000 1-5 18.50 .02236 18.8 .01871 18.95 .02915 18.6 .03536 .000 1-6 24.72 .01582 25.1 .00707 25.92 .01581 25.32 .01581 .000 1-7 35.07 .03391 35.79 .01225 36.28 .01581 35.95 .03162 .000 9-2 25.32 .01581 26.33 .01671 26.92 .01591 26.8 .02345 .000 9-8 27.71 .0133 28.63 .0123 28.93 .0273 28.42 .0122 .000 Table 6: LSD multiple comparison between the groups of each distance between 2 points for group C (for width of pps in (mm)) Groups 1-3 1-4 1-5 1-6 1-7 2-9 9-8 Mean diff sig Mean diff sig Mean diff Sig Mean diff sig Mean diff sig Mean diff Sig Mean diff Sig. C1 C2 -.90 .000 -1.64 .000 -.30 .000 -.38 .000 -.72 .000 -1.01 .000 -.92 .000 C1 C3 -1.68 .000 -1.68 .000 -.45 .000 -1.2 .000 -1.21 .000 -1.6 .000 -1.22 .000 C1 C4 -.60 .000 -1.47 .000 -.10 .000 -.60 .000 -.88 .000 -1.48 .000 -.71 .000 C2 C3 -.784 .000 -.04 .199 -.150 .000 -.82 .000 -.49 .000 -.59 .000 -.30 .000 C2 C4 .30 .000 .17 .000 .20 .000 -.22 .000 -.16 .000 -.47 .000 .21 .000 C3 C4 1.084 .000 .21 .000 .35 .000 .60 .000 .33 .000 .12 .000 .51 .000 The mean difference is significant at the .05 level. Table 7: Means, standard deviation and ANOVA of depth of points in pps area in (mm) of Group A (deep palatal vault) Points A1 control A2 Korecta wax A3 tracing comp. A4 single beed ANOVA Sig. Mean SD Mean SD Mean SD Mean SD 10 5 .30 7.6 .37 9.5 .30 6.5 .38 .000 11 5 .36 7.3 .58 8.9 .74 6.8 .6 .000 12 6.2 .2 7.9 .6 8.2 .3 7.5 .32 .000 13 6.5 .38 8.2 .31 9 .41 7.6 39 .000 Table 8: LSD multiple comparison between the groups of group A (deep palatal vault) for depth of pps Groups 10 point 11 12 13 Mean diff. Sig. Mean diff. Sig. Mean diff. Sig . Mean diff. Sig. A1 A2 -2.6 .000 -2.3 .000 -1.7 .000 -1.7 .000 A1 A3 -4.5 .000 -3.9 .000 -2.0 .000 -2.5 .000 A1 A4 -1.5 .000 -1.88 .000 -1.3 .000 -1.1 .000 A2 A3 -1.9 .000 -1.5 .001 -.30 .269 -.80 .004 A2 A4 1.1 .000 .44 .265 .4 .146 .6 .023 A3 A4 3.0 .000 2.02 .000 .70 .017 1.4 .000 The mean differences are significant at the .05 level J Bagh College Dentistry Vol. 25(4), December 2013 Evaluation of tissue Restorative Dentistry 23 Table 9: Means, standard deviation and ANOVA of depth of points in pps area in (mm)of group B (intermediate palatal vault ) Points B1 control B2 Korecta wax B3 tracing comp. B4 butterfly 2-3 mm ANOVA Sig. Mean SD Mean SD Mean SD Mean SD 10 5.7 .18 7.9 .53 8.9 .6 7.2 .46 .000 11 5.5 .33 7.5 .53 8.9 .6 6.9 .34 .000 12 6.2 .67 7.9 .25 8.7 .3 7.7 .18 .000 13 6.2 .38 7.8 .3 8.9 .25 7.8 .29 .000 Table 10: LSD multiple comparisons between the groups of group B (intermediate palatal vault) for depth of pps Groups 10 point 11 12 13 Mean diff. Sig. Mean diff. Sig. Mean diff. Sig . Mean diff. Sig. B1 B2 -2.2 .000 -2.0 .000 -1.7 .000 -1.5 .000 B1 B3 -3,2 .000 -3.4 .000 -2.5 .000 -2.6 .000 B1 B4 -1.5 .000 -1.4 .000 -1.5 .000 -1.52 .000 B2 B3 -1.0 .005 -1.4 .000 -.80 .006 -1.1 .000 B2 B4 .7 .038 .60 .068 .20 .444 .000 1.0 B3 B4 1.7 .000 2.0 .000 1.0 .001 1.1 .000 The mean differences are significant at the .05 level Table 11: Mean, standard deviation and ANOVA of depth of points in pps area in (mm) of group C (flat palatal vault) Points C1 control C2 Korecta wax C3 tracing comp. C4 Butterfly 3-4mm ANOVA Sig. Mean SD Mean SD Mean SD Mean SD 10 5.0 .30 7.2 .29 7.8 .36 6.5 .38 .000 11 5.3 .18 7.3 .14 7.9 .122 6.6 .46 .000 12 5.4 .10 7.0 .37 7.4 .32 6.3 .44 .000 13 5.5 .12 7.0 .37 7.3 .17 6.4 .41 .000 Table 12: LSD multiple comparisons between the groups of group c (flat palatal vault) for depth of pps Groups 10 point 11 12 13 Mean diff. Sig. Mean diff. Sig. Mean diff. Sig. Mean diff. Sig. C1 C2 -2.2 .000 -2.0 .000 -1.6 .000 -1.5 .000 C1 C3 -2.8 .000 -2.6 .000 -2.0 .000 -1.8 .000 C1 C4 -1.5 .000 -1.3 .000 -.9 .001 -.9 .000 C2 C3 -.6 .013 -.6 .003 -.4 .079 -.3 .133 C2 C4 .7 .005 .70 .001 .70 .005 .6 .006 C3 C4 1.3 .000 1.3 .000 1.1 .000 .9 .000 The mean differences are significant at the .05 level J Bagh College Dentistry Vol. 25(4), December 2013 Evaluation of tissue Restorative Dentistry 24 Fig. 1: Final impression with Fig. 2: Final impression with Korecta wax Spaced special tray by using light body Fig. 3: Final impression with Modeling Compound Fig. 4: Selection of 13 point for measuring Tissue displacement J Bagh College Dentistry Vol. 25(4), December 2013 Evaluation of tissue Restorative Dentistry 25 Fig. 6: Casts No. 2, 3 and 4 after transferring the points by the splint Fig. 5: Acrylic splint of cast No. 1 Fig. 7: 3D Three Dimension Scanner Laser Dent of CAD/CAM Fig. 8: 3D Three Dimensions Image of Stone Cast Fig. 9: Using reamer on the splint to measure the depth of PPS65