Influence of antiresorptive/antiangiogenic therapy on the extension of experimentally induced peri-implantitis lesions

Implant presence-triggered osteonecrosis: A scoping review

Unlike medication-related osteonecrosis of the jaw (MRONJ), implant presence-triggered osteonecrosis of the jaw (IPTO) is not well appreciated. Recent reports have suggested a mechanical aetiology unique to osseointegrated dental implants that may be responsible for this phenomenon. A scoping review was performed to consolidate the available evidence. Two reviewers independently searched the PubMed, EMBASE, CINAHL, and Cochrane Library databases. The study was performed according to the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) extension for scoping reviews. Studies that described or evaluated the development of IPTO in osseointegrated implants, which were placed prior to the commencement of anti-resorptive or anti-angiogenic agents, were included. Twenty-three (23) articles were included in this study. Patient characteristics, aetiopathogenesis, presentation, and treatment of the disease were evaluated. Most studies suggested a 6-month period between dental implant insertion and the commencement of anti-resorptive therapy as a criterion for IPTO. Both infective and mechanical processes were reported to be involved in the pathogenesis of IPTO. Most patients required surgical intervention to achieve resolution. While there are several knowledge gaps regarding IPTO, the evidence points towards a continuum in the pathogenesis of the disease, whereby there is a mechanical cause followed by secondary infection. Similar to typical MRONJ, the severity and treatment required also vary. Persistent peri‑implantitis features around a dental implant should alert the clinician to the possibility of IPTO in patients taking anti-resorptive or anti-angiogenic agents. Prompt identification of the disease may play a role in timely management or appropriate referrals.

Influence of antiresorptive/antiangiogenic therapy on changes in periodontal and oral tissue structures: a histomorphometrical analysis in rats

OBJECTIVE

The objective of this study was to investigate the influence of various antiresorptive and antiangiogenic medications on morphological changes in periodontal and oral tissue structures.

MATERIALS AND METHODS

Fifty-five Wistar rats randomly received dual application (i.e., at baseline and after 12-weeks) one of the following medications: (1) amino-bisphosphonate [zoledronate (Zo)], (2) RANKL inhibitor [denosumab (De)], (3) antiangiogenic [bevacizumab (Be)], (4) Zo + Be, (5) De + Be or (6) no medication [Control (Co)]. Periodontal and oral tissue biopsies were obtained at 17 (n = 21 animals, Phase 1, (De = 3, De + Be = 3, Zo = 5, Be = 3, Zo + Be = 2, Co = 5) and 29 (n = 34 animals, (De = 8, De + Be = 6, Zo = 2, Be = 7, Zo + Be = 4, Co = 7, Phase 2) weeks after the second drug application. The following outcomes were histomorphometrically assessed: periodontal space width in the coronal (PLS-C, mm) and apical sections (PLS- A), number of empty alveolar bone lacunae in the coronal, apical sections and at the apex at respective tooth sites (EL - C, EL- A, EL- Ap), mucosal thickness at edentulous alveolar ridge areas (MT, mm), and, when present, associated areas of inflammatory cell infiltrates (ICI, mm2).

RESULTS

Comparable mean PLS-C, PLS-A, ET-A, ET-C, ET-Ap, and MT values were observed in all experimental groups after Phases 1 and 2. The presence of ICI was identified in 3 animals in the Co group (Phase 1: 1, Phase 2: 2), and 17 animals in the test groups (Phase 1: 4; Phase 2: 14). The estimated ICI surface area was significantly higher in the Zo + Be group, followed by the Zo and Be groups compared to that measured in the Co group. The time (i.e., Phases 1 and 2) was not found to be a predictor for the extent of the ICI area. In all groups, the EL-C, EL-A, and EL-Ap values were significantly higher after Phase 2 compared to those assessed after Phase 1. The MT values were significantly reduced in all groups after Phase 2 compared to those measured after Phase 1.

CONCLUSIONS

The present evaluation was not able to find any morphological effects of different antiresorptive and antiangiogenic medications on periodontal and oral tissue structures. The presence of inflammatory cell infiltrates was more frequently observed in the animals administered with antiresorptive and antiangiogenic medications as well as combinations thereof.

CLINICAL RELEVANCE

Administration of antiresorptive and antiangiogenic medications may be capable of inducing inflammatory reactions in periodontal tissues.

Influence of antiresorptive/antiangiogenic therapy on the surgical treatment outcomes of experimentally induced peri-implantitis lesions

OBJECTIVE

To investigate the influence of various antiresorptive and antiangiogenic medications on the resolution of experimentally induced peri-implantitis lesions after different surgical treatment approaches.

MATERIALS AND METHODS

Forty-eight albino rats randomly received a dual application of the following medications: (1) amino-bisphosphonate (zoledronate (Zo)) (n = 8), (2) RANKL inhibitor (denosumab (De)) (n = 8), (3) antiangiogenic (bevacizumab (Be)) (n = 8), (4) Zo + Be (n = 8), (5) De + Be (n = 8), or (6) no medication (control (Co)) (n = 8). Ligature-induced peri-implantitis lesions were established at 2 maxillary implants over 16 weeks. Afterward, animals were randomly treated either with open flap debridement (OFD) or reconstructive therapy (RT). Treatment procedures were followed by a 12-week healing period. The histological outcomes included residual defect length (DL); defect width (DW) at the bone crest (BC-DW); 25%, 50%, and 75% of the DL; and areas of inflammatory cell infiltrate (ICT). When present, areas of bone sequester (BS) were assessed considering the animal as a statistical unit.

RESULTS

A total of 21 animals were analyzed (Zo: RT = 3, OFD = 1; De: RT = 3, OFD = 2; Be: OFD = 1; Zo + Be: RT = 2, OFD = 2; Co: RT = 3, OFD = 2). Implant loss rates were comparable among the experimental groups. Except for the 25% and 75% DW values that were significantly higher in the Zo + Be group compared to the Co group (p = 0.04 and p = 0.03, respectively), no significant differences were found among the experimental groups for the DL (lowest-Be: 0.56 mm; highest-Co: 1.05 mm), BC-DW (lowest-De: 0.86 mm, highest-Co: 1.07 mm), 50% DW (lowest-De: 0.86 mm; highest-Be + Zo: 1.29 mm), and ICT (lowest-Be: 0.56 mm2; highest-Be + Zo: 1.65 mm2). All groups, except for the Zo and Be following RT, showed presence of BS.

CONCLUSIONS

The present findings did not reveal a marked effect of various antiresorptive/antiangiogenic medications on the resolution of experimentally induced peri-implantitis lesions, regardless of the surgical approach employed (OFD and RT).

CLINICAL RELEVANCE

Resolution of peri-implantitis lesions may not be affected by the investigated antiresorptive/antiangiogenic medications.