case_images: PMC11178403_01
case_images: (a) Preoperative front and lateral profile. (b) Extraoral examination: face analysis. (c) Intraoral examination: shorter clinical crown. (d) Lip analysis. (e-f) Radiographic examination: collum angle (the supplementary angle of the crown-root angle).
case_images: CRID2024-6500762.001.jpg
case_images: PMC11178403_01_CRID2024-6500762.001.jpg
case_images: fig1
case_images: There was no relevant medical or family history.  Figure 1(a) shows the preoperative front and lateral profiles of the patient. The extraoral examination (Figure 1(b)) revealed vertical maxillary excess with larger measurements in the lower 1/3 of the face. Lip analysis (Figure 1(d)) revealed a hyperactive upper lip with 10 mm of muscular activity, along with an 8 mm gingival display from one side of the maxillary molar to the opposite side during smiling. Intraoral examination (Figure 1(c)) did not reveal any soft tissue abnormalities. Radiographic examination (Figures 1(e) and 1(f)) showed a positive collum angle between alveolar bone plateau and central incisors.
case_images: Digital planning: (a) computed tomography (CT) scan; (b) virtual planning to plan position, size, and shape of PMMA block; (c) prototype of cropped maxillary segment for test fit; (d) prototype of mould for fabrication of PMMA block; (e) parts of 3D printed mould. Surgical intervention: (f) bleeding points are marked using Chu's aesthetic gauge; (g) gingivectomy is performed; (h) full thickness flap elevated; (i) passive adaptation of PMMA block checked by placing over printed maxillary segment; (j) screw positions are marked, and two holes are drilled of 2 mm diameter using bone drills; (k) extraoral placement of titanium screw over the prepared PMMA block; (l-m) PMMA block placement; (n) fixation of PMMA block using titanium screws; (o) flap adaptation using sling sutures; (p) postoperative CBCT to confirm the position of PMMA block; (q) pre- and postoperative intraoral photographs.
case_images: CRID2024-6500762.002.jpg
case_images: PMC11178403_01_CRID2024-6500762.002.jpg
case_images: fig2
case_images: Additionally, a computed tomography (CT) scan (Figure 2(a)) was performed to evaluate alveolar bone anatomy and for virtual planning of a PMMA block. The prototypes developed included (i) a cropped maxillary segment for test fitting and (ii) a mould for the fabrication of the PMMA block (Figures 2(b), 2(c), 2(d), and 2(e)). T-bar tip of the proportion gauge was then replaced with the Biologic Periogauge (BLPG) tip. This assists in achieving the desired biologic crown length and allows for osteoplasty where necessary using spherical burs at high speed under copious saline irrigation (Figures 2(f), 2(g), and 2(h)). Later, at the predetermined position (i.e., one drill between teeth 12 and 13 and the other between teeth 22 and 23), two holes were placed in the PMMA block using bone drills (Figures 2(i), 2(j), 2(k), 2(l), and 2(m)). The flap was repositioned with sling sutures (Figures 2(n) and 2(o)). Immediately after surgery, a CBCT was taken to check the final screw position (Figure 2(p)).
case_images: (a) PMMA bone cement properties. (b-f) Bone cement manipulation and adaptation in the 3D printed mould.
case_images: CRID2024-6500762.003.jpg
case_images: PMC11178403_01_CRID2024-6500762.003.jpg
case_images: fig3
case_images: When the mixture reached the dough stage, indicated by no longer sticking to the gloves and becoming easily adaptable, it was transferred into the 3D printed mould (Figures 3(b), 3(c), 3(d), 3(e), and 3(f)).
case_images: (a) Pre- and (b) postoperative front and lateral profile of the patient.
case_images: CRID2024-6500762.004.jpg
case_images: PMC11178403_01_CRID2024-6500762.004.jpg
case_images: fig4