Narja Sahm

Impact of the method of surface debridement and decontamination on the clinical outcome following combined surgical therapy of peri-implantitis: a randomized controlled clinical study

OBJECTIVES The study aimed at investigating the impact of two surface debridement/decontamination (DD) methods on the clinical outcomes of combined surgical treatment of peri-implantitis. MATERIAL AND METHODS Thirty-two patients suffering from advanced peri-implantitis (n=38 combined supra- and intra-bony defects) were treated with flap surgery, granulation tissue removal, and implantoplasty at buccally and supracrestally exposed implant parts. The intra-bony aspects were randomly allocated to surface DD using either (i) an Er:YAG laser (ERL) device, or (ii) plastic curets+cotton pellets+sterile saline (CPS). In both groups, the intra-bony component was augmented with a natural bone mineral and covered with a collagen membrane. Clinical and radiographic parameters were recorded at baseline and after 6 months of non-submerged healing. RESULTS Two patients were lost during follow-up. At 6 months, ERL-treated sites failed to reveal higher reductions in mean bleeding on probing (ERL: 47.8 ± 35.5 versus CPS: 55.0 ± 31.1%) and CAL values (ERL: 1.5 ± 1.4 versus CPS: 2.2 ± 1.4 mm) when compared with the CPS group. Both groups exhibited a comparable radiographic bone fill at the intra-bony defect component. CONCLUSION The study failed to demonstrate a significant impact of the method of surface DD on the clinical outcome following combined surgical therapy of advanced peri-implantitis lesions.

Impact of defect configuration on the clinical outcome following surgical regenerative therapy of peri-implantitis.

OBJECTIVES The present study aimed at investigating the impact of defect configuration on the clinical outcome of surgical regenerative therapy of peri-implantitis lesions using a natural bone mineral in combination with a collagen membrane (NBM+CM). MATERIALS AND METHODS Twenty-seven patients (n=27 defects) exhibited three different types of peri-implantitis lesions including either Class Ib (buccal dehiscence+semicircumferential), Class Ic (buccal dehiscence+circumferential), or Class Ie (circumferential) intra-bony defects (n=9 defects per group). All defects were treated with access flap surgery and the application of NBM+CM. RESULTS At 6 and 12 months, Class Ie defects tended to reveal higher changes in the mean probing depth (PD) and clinical attachment level (CAL) values when compared with Class Ib and Class Ic groups. However, significant differences were only observed at 6 months (PD: 2.9 +/- 0.3 versus 1.4 +/- 0.5 versus 1.3 +/- 0.7 mm; CAL: 2.5 +/- 0.5 versus 0.9 +/- 0.8 versus 0.9 +/- 0.7 mm). Site-level analysis has pointed to lowest PD and CAL changes at the midbuccal aspect of Class Ib and Class Ic groups. CONCLUSION Defect configuration may have an impact on the clinical outcome following surgical regenerative therapy of peri-implantitis lesions. While Class Ie defects seem to be promising in conjunction with NBM+CM, Class Ib and Class Ic may be considered as unfavourable.

Surgical regenerative treatment of peri‐implantitis lesions using a nanocrystalline hydroxyapatite or a natural bone mineral in combination with a collagen membrane: a four‐year clinical follow‐up report

OBJECTIVES The present case series aimed at investigating the 4-year clinical outcomes following surgical regenerative therapy of peri-implantitis lesions using either a nanocrystalline hydroxyapatite (NHA) or a natural bone mineral in combination with a collagen membrane (NBM+CM). MATERIALS AND METHODS Twenty patients suffering from moderate peri-implantitis (n=20 intrabony defects) were randomly treated with (1) access flap surgery (AFS) and the application of NHA (n=9), or with AFS and the application of NBM+CM (n=11). Clinical and radiographic (R) parameters were recorded at baseline (R) and after 36 and 48 (R) months of non-submerged healing. RESULTS One patient from the NBM+CM group was discontinued from the study due to severe pus formation at 36 months. Compared with NHA, the application of NBM+CM resulted in higher mean PD reductions (NBM+CM: 2.5 +/- 0.9 mm versus NHA: 1.1 +/- 0.3 mm) and clinical attachment-level gains (NBM+CM: 2.0 +/- 1.0 mm versus NHA: 0.6 +/- 0.5 mm) at 48 months. A radiographic bone fill was observed for five sites in the NHA group, and eight sites in the NBM+CM group. CONCLUSION While the application of NBM+CM resulted in clinical improvements over a period of 4 years, the long-term outcome obtained with NHA without barrier membrane must be considered as poor.

Non‐surgical treatment of peri‐implantitis using an air‐abrasive device or mechanical debridement and local application of chlorhexidine: a prospective, randomized, controlled clinical study

OBJECTIVES The aim of this prospective, parallel group designed, randomized controlled clinical study was to evaluate the effectiveness of an air-abrasive device (AAD) for non-surgical treatment of peri-implantitis. MATERIAL AND METHODS Thirty patients, each of whom displayed at least one implant with initial to moderate peri-implantitis, were enrolled in an oral hygiene program (OHI) and randomly instrumented using either (1) AAD (amino acid glycine powder) or (2) mechanical debridement using carbon curets and antiseptic therapy with chlorhexidine digluconate (MDA). Clinical parameters were measured at baseline, 3 and 6 months after treatment [e.g. bleeding on probing (BOP), probing depth (PD), clinical attachment level (CAL)]. RESULTS At 6 months, AAD group revealed significantly higher (p<0.05; unpaired t-test) changes in mean BOP scores when compared with MDA-treated sites (43.5 ± 27.7%versus 11.0 ± 15.7%). Both groups exhibited comparable PD reductions (AAD: 0.6 ± 0.6 mm versus MDA: 0.5 ± 0.6 mm) and CAL gains (AAD: 0.4 ± 0.7 mm versus MDA: 0.5 ± 0.8 mm) (p>0.05; unpaired t-test, respectively). CONCLUSIONS Within its limitations, the present study has indicated that (i) both treatment procedures resulted in comparable but limited CAL gains at 6 months, and (ii) OHI+AAD was associated with significantly higher BOP reductions than OHI+MDA.

Combined surgical therapy of peri‐implantitis evaluating two methods of surface debridement and decontamination. A two‐year clinical follow up report

OBJECTIVES The study aimed at evaluating the 2-year results obtained following combined surgical resective and regenerative treatment of advanced peri-implantitis defects comparing two methods of surface debridement/decontamination (DD). MATERIAL & METHODS Twenty-four patients (n = 26 combined supra- and intrabony defects) completed the 24 months follow-up observation following access flap surgery, granulation tissue removal and implantoplasty at bucally and supracrestally exposed implant parts. The remaining aspects were randomly allocated to surface DD using either (i) an Er:YAG laser (ERL) device, or (ii) plastic curets + cotton pellets + sterile saline (CPS) were augmented with a natural bone mineral and covered with a collagen membrane. RESULTS At 24 months, ERL treated sites failed to reveal significantly higher reductions in mean BOP (ERL: 75.0 ± 32.6% versus CPS: 54.9 ± 30.3%) and CAL values (ERL: 1.0 ± 2.2 mm versus CPS: 1.2 ± 2.2 mm) when compared with the CPS group. In both groups, mean CAL values were not significantly different when compared with baseline. CONCLUSION The long-term stability of clinical outcomes obtained following combined surgical therapy of advanced peri-implantitis may be influenced by factors other than the method of surface debridement/decontamination.

Stability of crestal bone level at platform-switched non-submerged titanium implants: a histomorphometrical study in dogs.

OBJECTIVES To investigate the influence of platform switching on crestal bone level changes at non-submerged titanium implants over a period of 6 months. MATERIAL AND METHODS Titanium implants (n=72) were placed at 0.4 mm above the alveolar crest in the lower jaws of 12 dogs and randomly assigned to either matching or non-matching (circumferential horizontal mismatch of 0.3 mm) healing abutments. At 4, 8, 12, and 24 weeks, dissected blocks were processed for histomorphometrical analysis. Measurements were made between the implant shoulder (IS) and the apical extension of the long junctional epithelium (aJE), the most coronal level of bone in contact with the implant (CLB), and the level of the alveolar bone crest (BC). RESULTS At 24 weeks, differences in the mean IS-aJE, IS-CLB, and IS-BC values were 0.2 +/- 1.2, 0.3 +/- 0.7, and 0.3 +/- 0.8 mm at the buccal aspect, and 0.2 +/- 0.9, 0.3 +/- 0.5, and 0.3 +/- 0.8 mm at the lingual aspect, respectively. Comparisons between groups revealed no significant differences at either the buccal or the lingual aspects. CONCLUSIONS It was concluded that (i) bone remodelling was minimal in both groups and (ii) platform switching may not be of crucial importance for maintenance of the crestal bone level.

Four‐year follow‐up of combined surgical therapy of advanced peri‐implantitis evaluating two methods of surface decontamination

OBJECTIVES To investigate the impact of two surface decontamination methods on the long-term outcomes following combined surgical resective/regenerative therapy of advanced peri-implantitis lesions. MATERIAL AND METHODS Seventeen patients (n = 17 combined supra- and intrabony-defects) completed the 48 months follow-up observation following access flap surgery, granulation tissue removal and implantoplasty at bucally and supracrestally exposed implant parts. The remaining unmodified implant surface areas were randomly treated using either (i) an Er:YAG laser (ERL), or (ii) plastic curets + cotton pellets + sterile saline (CPS), and augmented with a natural bone mineral + collagen membrane. RESULTS At 48 months, CPS-treated sites tended to reveal higher reductions in mean BOP (CPS: 85.2 ± 16.4% versus ERL: 71.6 ± 24.9%) and CAL values (CPS: 1.5 ± 2.0 mm versus ERL: 1.2 ± 2.0 mm) when compared with the ERL group. In both groups, clinical outcomes were not directly influenced by the initial defect configuration. CONCLUSION The 4-year clinical outcomes obtained following combined surgical resective/regenerative therapy of advanced peri-implantitis were not influenced by the method of surface decontamination.

Surgical therapy of advanced ligature‐induced peri‐implantitis defects: cone‐beam computed tomographic and histological analysis

OBJECTIVES To evaluate radiological bone level (RBL) (i.e. cone-beam computed tomography) and histological bone levels (HBL) as well as re-osseointegration [bone-to-implant contact (BIC)] after surgical resective (i.e. implantoplasty) and/or regenerative therapy of advanced ligature-induced peri-implantitis in dogs. MATERIAL AND METHODS At all defect sites (n=6 dogs, n=48 implants), the intrabony component was filled with a particulate bovine-derived natural bone mineral (NBM). The supracrestal component was treated by either the application of an equine bone block (EB) or implantoplasty. In a split-mouth design, NBM and EB were soak-loaded with recombinant human bone morphogenetic protein (rhBMP)-2 or sterile saline. All sites were covered by a native collagen membrane and left to heal in a submerged position for 12 weeks. RESULTS A premature wound exposure was observed at nine defect sites. Mean RBL and HBL values were lowest in the P+rhBMP-2 group, reaching statistical significance when compared with the EB group. Mean BIC values were comparable in all groups. Within-group comparisons commonly revealed a close correlation between RBL and HBL values. CONCLUSIONS It was concluded that (i) in all groups the investigations failed to predictably obtain complete defect resolution, (ii) the surgical procedure was associated with high exposure rates, and (iii) RBL was closely correlated with HBL.

Impact of the outcome of guided bone regeneration in dehiscence‐type defects on the long‐term stability of peri‐implant health: clinical observations at 4 years

OBJECTIVES To investigate the impact of residual defect height (RDH) following guided bone regeneration (GBR) in dehiscence-type defects on the long-term stability of peri-implant health after a period of 4 years. MATERIAL AND METHODS The RDH values in dehiscence-type defects at titanium implants were clinically assessed after 4 months of submerged healing following augmentation using a natural bone mineral (NBM) and a randomized application of either a cross-linked- (VN) or a native collagen membrane (BG) (n=12 patients each). The RDH values were classified as absent (0 mm, control; n=8), minimal (1 mm, test 1; n=8), or advanced (>1 mm, test 2; n=8). Clinical parameters (i.e. bleeding on probing [BOP], probing pocket depth [PD], mucosal recession [MR]) were recorded (mesio-, mid-, and disto-buccal aspects) at 4 years after prosthesis installation. RESULTS The mean PD (2.9±0.7, 2.8±0.7, 2.7±0.8 mm) values at 4 years were comparable in all the groups investigated. The mean MR values tended to be increased in both the test groups (0.5±0.7, 0.4±0.6 mm, respectively), when compared with the control group (0.2±0.3 mm) (P>0.05, respectively). The mean BOP values were also increased in both the test groups (45.8±30.5%, 54.1±24.8%, respectively), even reaching statistical significance when comparing test 2 and control (29.1±21.3%) groups (P=0.02). CONCLUSION The present study indicated that (i) implants exhibiting RDH values >1 mm are at a higher risk of developing peri-implant disease and (ii) positive RDH values may be associated with an increase in MR and may therefore compromise the overall esthetic outcome of implant therapy.

Combined surgical therapy of advanced peri‐implantitis lesions with concomitant soft tissue volume augmentation. A case series

OBJECTIVES Mucosal recessions are a common finding following surgical treatment of peri-implantitis, thus compromising the overall esthetic outcome of implant therapy. This case series aimed at evaluating the clinical outcome of a combined surgical therapy of advanced peri-implantitis lesions with concomitant soft tissue volume augmentation. MATERIAL AND METHODS Ten patients (n = 13 implants exhibiting combined supra- and intrabony defects) underwent access flap surgery, implantoplasty at bucally and supracrestally exposed implant parts, and augmentation of the intrabony components using a natural bone mineral and a native collagen membrane after surface decontamination. A subepithelial connective tissue graft was harvested from the palate and adapted to the wound area to support transmucosal healing. Clinical parameters (i.e. bleeding on probing--BOP; probing depths--PD; mucosal recession--MR; clinical attachment level--CAL) were recorded at baseline and after 6 months. RESULTS At 6 months, the combined surgical procedure was associated with a significant reduction in mean BOP (74.39 ± 28.52%), PD (2.53 ± 1.80 mm), and CAL (2.07 ± 1.93 mm) values. Site-level analysis has pointed to a slight increase in mean mucosal height (0.07 ± 0.5 mm) at the buccal aspects (i.e. mb, b, db). CONCLUSION The combined surgical procedure investigated may be effective in controlling advanced peri-implantitis lesions without compromising the overall esthetic outcome in the short term.