Hard and soft tissue regeneration of severe peri-implantitis defects with the laser-assisted peri-implant defect regeneration technique: 3-year results

Abstract

Purpose: This retrospective cohort study evaluates the regeneration of severe peri-implantitis deficiencies treated with the laser-assisted peri-implant defect regeneration (LAPIDER) approach within a 3-year follow-up.

Methods: Twenty-four implants with severe peri-implantitis in 18 patients were treated according to the LAPIDER technique. In contrast to classic techniques for reconstructive peri-implantitis surgery with a marginal incision, a buccal split-flap preparation avoiding papillae separation was used. After a coronal flap elevation and a laser-assisted peri-implant defect cleaning, connective tissue and autogenous bone grafting was performed. Primary outcomes were the changes of the marginal bone levels (MBL) and the buccal bone thickness. Secondary outcomes included implant survival, peri-implant probing depths (PPD), bleeding on probing (BOP), recession, width of keratinized mucosa (KMW), thickness of keratinized mucosa (KMT), soft tissue esthetics (PES), and implant success.

Results: MBL improved interproximal by 3.10 ± 2.02 mm (p < 0.001), buccal by 3.49 ± 2.89 mm (p < 0.001), and lingual by 1.46 ± 1.98 mm (p = 0.003); buccal bone thickness by 0.55 ± 0.60 mm (p = 0.005), and 1.01 ± 1.25 mm (p = 0.001) at 1 and 3 mm below reference level. Two implants were removed; 22 implants were still in function at a mean follow-up of 36 months. PPD changed from 5.05 ± 1.39 to 3.08 ± 0.71 mm (p < 0.001); recession was reduced from 2.07 ± 1.70 to 0.91 ± 1.13 mm (p = 0.001); KMW increased from 2.91 ± 1.81 to 4.18 ± 1.67 mm (p = 0.006); KMT improved from 1.73 ± 0.50 to 2.44 ± 0.43 mm (p < 0.001); PES changed from 7.7 ± 2.8 to 10.7 ± 1.9 (p < 0.001). 45.8% to 54.2% of the implants met the criteria of implant success.

Conclusions: The favorable results document the proof of principle for the regeneration of severe peri-implant hard and soft tissue deficiencies by the LAPIDER treatment approach.

Keywords: Bone graft; Bone regeneration; Dental implant; Keratinized mucosa; Peri-implantitis; Recession; Reconstructive therapy; Soft tissue graft; Surface decontamination.

Fig. 1

Illustration of the LAPIDER treatment approach. a Presence of a severe peri-implantitis defect. b Split-flap preparation from mucogingival border in apical direction. c Apical separation of the periosteum and subperiosteal coronal flap elevation. d Peri-implant defect cleaning and decontamination of the implant surface by the Er:YAG laser. e Subperiosteal connective tissue grafting. f Peri-implant defect augmentation with autogenous bone chips. g Periosteal mattress suturing with resorbable suturing material. h Mucosal suturing for a bilaminar wound closure

Fig. 2

a Severe peri-implantitis lesion with suppuration and bleeding on probing. b Access to the severe buccal peri-implant bony lesion by the LAPIDER approach. c Hard and soft tissue defect grafting and bilaminar wound closure. d At 3-year follow-up examination no signs of a peri-implant infection are left. e The baseline radiograph reveals a severe interproximal bone loss. f A radiograph at 2-year follow-up examination shows the complete interproximal regeneration. g The pre-operative CB-CT shows a severe buccal bone loss. h At 3-year follow-up a CB-CT reveals the complete bone regeneration to the implant shoulder level

Fig. 3

a Severe peri-implantitis lesion with suppuration and an insufficient width of the keratinized mucosa. b Implant surface decontamination with the Er:YAG laser. c Hard and soft tissue grafting according to the LAPIDER technique. d Periosteal suturing to cover the autogenous grafts. e Uneventful healing 9 months after LAPIDER surgery, but still without a sufficient zone of attached mucosa. f 3-year follow-up examination after an additional apically positioned flap with FGG. g Severe interproximal bone loss at pre-operative examination. h Radiograph at 3-year follow-up examination reveals significant vertical bone regeneration. i Severe buccal and lingual bone loss at baseline. j CB-CT at 3-year follow-up examination shows a pronounced buccal and lingual bone regeneration

Fig. 4

Interproximal marginal bone-level changes from pre-operative examination to 1-year, to 2-year, and to 3-year follow-up examinations

Fig. 5

Survival function according to Kaplan–Meier for all 24 implants treated by the LAPIDER concept