Objectives: Evaluation of an ex vivo porcine model to investigate the influence of periodontal instrumentation on soft tissue.
Material and methods: In each of 120 pig mandibles, one molar tooth was chosen at random and instrumented. For subgingival debridement, two different low abrasive airpolishing powders (glycine d90 = 25 μm, erythritol d90 = 14 μm, n = 30 teeth each), curets, and a piezoelectric ultrasonic scaler were used (n = 30 teeth each). Thirty teeth in 30 other mandibles served as the untreated control. Gingival biopsies were histologically assessed for destruction using a four-graded scale.
Results: The porcine model was deemed suitable for the planned investigation. Hand instrumentation and ultrasonic scaling caused higher tissue damage than both low abrasive airpolishing modes (Fisher's exact test, p = 0.0025). Glycine powder led to less, yet non-statistical noticeable gingival changes compared to erythritol-based powder (Fisher's exact test, p = 0.39).
Conclusion: An animal model using pig jaws may be used as a preliminary model to analyze histological effects of periodontal instrumentation in advance of studies performed in human tissues. Among the techniques assessed, low abrasive airpolishing (LAA) caused the smallest tissue damage.
Clinical relevance: To avoid gingival damage using LAA, histological observations of gingival tissue are needed. Since numerous powders for LAA have been developed and it may be expected that additional products will follow, it appears to be useful to establish ex vivo animal models to prove the powders safety.
Keywords: Erythritol; Glycine; Low abrasive airpolishing; Periodontal instrumentation; Porcine model.