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Journal of Peking University (Health Sciences) ›› 2025, Vol. 57 ›› Issue (1): 65-72. doi: 10.19723/j.issn.1671-167X.2025.01.010

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Influence of emergence profile designs on the peri-implant tissue in the mandibular molar: A randomized controlled trial

Juan WANG, Lixin QIU, Huajie YU*()   

  1. Fourth Clinical Division, Peking University School and Hospital of Stomatology & National Center of Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices & Beijing Key Laboratory of Digital Stomatology, Beijing 100081, China
  • Received:2023-10-09 Online:2025-02-18 Published:2025-01-25
  • Contact: Huajie YU E-mail:yuhuajie666@163.com
  • Supported by:
    the Beijing Natural Science Foundation(J230032);the Program for New Clinical Techniques and Therapies of Peking University School and Hospital of Stomatology(PKUSSNCT-21A10)

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Abstract:

Objective: To compare the influence of different emergence profile of implants in mandibular molar on the peri-implant soft tissue. Methods: Forty-four implants were divided into two equal groups by mucosal thickness, ≥2 mm (group A) or < 2 mm (group B), and were randomly included in the test group and the control group. In the control group, the patients were treated by a prosthesis with no transmucosal modifications (subgroups A1 and B1). In groups A1 and B1, the prostheses maintained the original emergence profile of the healing abutment. In the test group, the prostheses were designed based on a width-to-height ratio (W/H) of 1.3 ∶ 1 (subgroups A2 and B2). In group A2, the buccal transmucosal configuration design was slightly concave, and in group B2, the prostheses were designed with convex buccal transmucosal configuration. Assessments were made before delivery of the definitive restoration (T0), one month (T1) and 12 months (T2) after loading. The soft tissue and prosthesis information were obtained by intraoral scan and were converted to digital models. The digital models of different time were superimposed together. Buccal mucosal W/H, emergence angle (EA) and buccal mucosal margin recession (ΔGM) were measured. Results: One year after loading, the buccal mucosal margin recession in the test group (groups A2 and B2) was significantly lower than that in the control group (groups A1 and B1). The ΔGM in group A2 was significantly lower than that in group A1 (P=0.033), but in groups B1 and B2, it was not significantly different. The W/H in group A2 increased significantly one month after loading, but remained stable at one year. In the A1 group, the W/H changed little from initial to one month, but increased significantly at one year after loading. The W/H in group B2 remained stable from the beginning to one year, while in group B1, it changed little one month after loading, but increased significantly by one year. Conclusion: When the initial mucosal thickness was ≥2 mm, the slightly concave prosthesis designed based on the biological W/H significantly maintained the level of buccal mucosa. When the mucosal thickness was < 2 mm, the slightly convex prosthesis design maintained a more stable W/H over one year.

Key words: Emergence profile, Dental implants, single-tooth, Gingival recession, Mouth mucosa

CLC Number: 

  • R783.6

Figure 1

Measurement of the supracrestal soft tissue thickness A, supracrestal soft tissue thickness ≥2 mm in the thick mucosal group (group A); B, supracrestal soft tissue thickness < 2 mm in the thin mucosal group (group B)."

Figure 2

Prostheses with different emergence profile designs A, group A1: prosthesis with the original emergence profile of the healing abutment in the control group with thick mucosal; B, group A2: prosthesis with a slightly convex buccal emergence profile based on W/H ratio in the test group with thick mucosal; C, group B1: prosthesis with the original emergence profile of the healing abutment in the control group with thin mucosal; D, group B2: prosthesis with a concave buccal emergence profile based on W/H ratio in the test group with thin mucosal. W/H ratio, width-to-height ratio."

Figure 3

Digital model align and management plane establish A, the digital model at T0 was aligned with the digital model of healing abutment; B, the digital models at T1 and T2 were aligned with digital model of prosthesis; C, the measurement plane was established by central axis of analog (line O) and the buccal zenith of the implant site (point A); D, the measurement plane of original state; E, the measurement plane after loading. T0, before loading; T1, one month after loading; T2, one year after loading."

Figure 4

Measurement diagram of buccal mucosal W/H, emergence angle and buccal mucosal margin recession A, examination of the buccal soft tissue width (W) and height (H); B, measurement of the initial emergence angle. Point B, the most coronal point of the buccal mucosa; Line O, the implant long axis; Line B, the tangent line of the restoration at point B; C, the measurement of the change in buccal mucosal margin recession (ΔGM)."

Table 1

Patient and intervention characteristics"

ItemsThick mucosal group (group A)Thin mucosal group (group B)
Control group (group A1)Test group (group A2)Control group (group B1)Test group (group B2)
Female, n (%)5 (55)5 (50)9 (82)7 (58)
Mean age/years41.741.847.835.9
Inserted implant number11101112
Patients number10101010

Table 2

Measurements of height and width of mucosal and the W/H"

ItemsT0T1T2
H/mm, ${\bar x}$±sW/mm, ${\bar x}$±sW/HH/mm, ${\bar x}$±sW/mm, ${\bar x}$±sW/HH/mm, ${\bar x}$±sW/mm, ${\bar x}$±sW/H
Group A
Group A13.45±0.393.42±1.020.993.08±0.483.15±0.561.032.55±0.563.15±0.741.26*
Group A23.35±0.432.73±0.470.82#2.70±0.463.37±0.621.252.57±0.573.08±0.681.20
Group B
Group B12.13±0.532.43±0.561.182.00±0.552.63±0.521.381.55±0.372.60±0.571.73*
Group B22.25±0.712.65±1.021.222.01±0.722.56±0.691.351.87±0.792.46±0.631.48

Figure 5

Changes of the W/H at various time points A, the W/H in the thick mucosal group (group A); B, the W/H in the thin mucosal group (group B). * the W/H at T2 in the control group was significantly different from those at T0 and T1 in both thick and thin mucosal group. # the W/H at T0 in the test group was significantly different from those at T1 and T2 in the thick mucosal group. W/H, width-to-height ratio; T0, before loading; T1, one month after loading; T2, one year after loading."

Table 3

Emergence angle (EA) and buccal mucosal margin change (ΔGM) over one year"

ItemsEA/(°)，${\bar x}$±sΔGM/mm, ${\bar x}$±s
Group AGroup A144.03±11.50*0.63±0.38*
Group A231.06±9.78*0.13±0.32*
Group BGroup B134.44±12.180.45±0.50
Group B237.83±11.160.17±0.37
Control groupGroups A1 and B139.46±12.820.54±0.45#
Test groupGroups A2 and B234.63±11.130.15±0.34
1 吴敏杰, 张相皞, 邹立东, 等. 临时冠成型术后1年牙龈稳定性的临床观察[J]. 北京大学学报(医学版), 2014, 46 (6): 954- 957.
doi: 10.3969/j.issn.1671-167X.2014.06.027
2 Linkevicius T , Puisys A , Linkeviciene L , et al. Crestal bone stability around implants with horizontally matching connection after soft tissue thickening: A prospective clinical trial[J]. Clin Implant Dent Relat Res, 2015, 17 (3): 497- 508.
doi: 10.1111/cid.12155
3 Kim S , Oh KC , Han DH , et al. Influence of transmucosal designs of three one-piece implant systems on early tissue responses: A histometric study in beagle dogs[J]. Int J Oral Maxillofac Implants, 2010, 25 (2): 309- 314.
4 Lee YM , Kim DY , Kim JY , et al. Peri-implant soft tissue level secondary to a connective tissue graft in conjunction with imme-diate implant placement: A 2-year follow-up report of 11 consecutive cases[J]. Int J Periodontics Restorative Dent, 2012, 32 (2): 213- 222.
5 Linkevicius T , Puisys A , Steigmann M , et al. Influence of vertical soft tissue thickness on crestal bone changes around implants with platform switching: A comparative clinical study[J]. Clin Implant Dent Relat Res, 2015, 17 (6): 1228- 1236.
doi: 10.1111/cid.12222
6 Linkevicius T , Apse P , Grybauskas S , et al. The influence of soft tissue thickness on crestal bone changes around implants: A 1-year prospective controlled clinical trial[J]. Int J Oral Maxillofac Implants, 2009, 24 (4): 712- 719.
7 Zhang Z , Shi D , Meng H , et al. Influence of vertical soft tissue thickness on occurrence of peri-implantitis in patients with periodontitis: A prospective cohort study[J]. Clin Implant Dent Relat Res, 2020, 22 (3): 292- 300.
doi: 10.1111/cid.12896
8 Spinato S , Stacchi C , Lombardi T , et al. Biological width establishment around dental implants is influenced by abutment height irrespective of vertical mucosal thickness: A cluster randomized controlled trial[J]. Clin Oral Implants Res, 2019, 30 (7): 649- 659.
doi: 10.1111/clr.13450
9 Borges T , Leitao B , Pereira M , et al. Influence of the abutment height and connection timing in early peri-implant marginal bone changes: A prospective randomized clinical trial[J]. Clin Oral Implants Res, 2018, 29 (9): 907- 914.
doi: 10.1111/clr.13343
10 Wennstrom JL . Mucogingival considerations in orthodontic treatment[J]. Semin Orthod, 1996, 2 (1): 46- 54.
doi: 10.1016/S1073-8746(96)80039-9
11 Bengazi F , Wennstrom JL , Lekholm U . Recession of the soft tissue margin at oral implants: A 2-year longitudinal prospective study[J]. Clin Oral Implants Res, 1996, 7 (4): 303- 310.
doi: 10.1034/j.1600-0501.1996.070401.x
12 Nozawa T , Enomoto H , Tsurumaki S , et al. Biologic height-width ratio of the buccal supra-implant mucosa[J]. Eur J Esthet Dent, 2006, 1 (3): 208- 214.
13 Farronato D , Manfredini M , Mangano F , et al. Ratio between height and thickness of the buccal tissues: A pilot study on 32 single implants[J]. Dent J (Basel), 2019, 7 (2): 40.
14 Wang J , Tang Y , Qiu L , et al. Influence of buccal emergence profile designs on peri-implant tissues: A randomized controlled trial[J]. Clin Implant Dent Relat Res, 2022, 24 (3): 329- 338.
doi: 10.1111/cid.13088
15 Du JK , Li HY , Wu JH , et al. Emergence angles of the cementoenamel junction in natural maxillary anterior teeth[J]. J Esthet Restor Dent, 2011, 23 (6): 362- 369.
doi: 10.1111/j.1708-8240.2011.00471.x
16 Katafuchi M , Weinstein BF , Leroux BG , et al. Restoration contour is a risk indicator for peri-implantitis: A cross-sectional radiographic analysis[J]. J Clin Periodontol, 2018, 45 (2): 225- 232.
doi: 10.1111/jcpe.12829
17 Yi Y , Koo KT , Schwarz F , et al. Association of prosthetic features and peri-implantitis: A cross-sectional study[J]. J Clin Periodontol, 2020, 47 (3): 392- 403.
doi: 10.1111/jcpe.13251
18 González-Martín O , Lee E , Weisgold A , et al. Contour management of implant restorations for optimal emergence profiles: Guidelines for immediate and delayed provisional restorations[J]. Int J Periodontics Restorative Dent, 2020, 40 (1): 61- 70.
doi: 10.11607/prd.4422
19 王鹃, 尉华杰, 邱立新. 前牙种植修复体穿龈形态设计的研究进展[J]. 中华口腔医学杂志, 2020, 55 (6): 417- 420.
20 Rompen E , Raepsaet N , Domken O , et al. Soft tissue stability at the facial aspect of gingivally converging abutments in the esthetic zone: A pilot clinical study[J]. J Prosthet Dent, 2007, 97 (Suppl 6): S119- S125.
21 Su H , Gonzalez-Martin O , Weisgold A , et al. Considerations of implant abutment and crown contour: Critical contour and subcritical contour[J]. Int J Periodontics Restorative Dent, 2010, 30 (4): 335- 343.
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