title: Non-Invasive Periodontal Probing Through Fourier-Domain Optical Coherence Tomography.
abstract: BACKGROUND
  Periodontitis is a multifactorial and infectious disease that may result in significant debilitation. The aim of this study is to exploit two optical coherence tomography (OCT) systems operating in the Fourier domain at different wavelengths, 930 and 1,325 nm, for structural analysis of periodontal tissue in porcine jaws.
  
  
  METHODS
  Five fresh porcine jaws were sectioned and stored in formalin before OCT analysis. Two- and three-dimensional OCT images of the tooth/gingiva interface were performed, and measurements of the gingival structures were obtained. The 930-nm OCT system operates in the spectral domain, whereas the 1,325-nm system is a swept-source model. Stereomicroscope images, the gold standard, were used for direct comparison.
  
  
  RESULTS
  Through image analysis, it is possible to identify the free gingiva and the attached gingiva, the calculus deposition over tooth surfaces, and the subgingival calculus that enables the enlargement of the gingival sulcus. In addition, the gingival thickness and the gingival sulcus depth can be non-invasively measured, varying from 0.8 to 4 mm.
  
  
  CONCLUSIONS
  Regarding the ability of the two OCT systems to visualize periodontal structures, the system operating at 1,325 nm shows a better performance, owing to a longer central wavelength that allows deeper tissue penetration. The results with the system at 930 nm can also be used, but some features could not be observed due to its lower penetration depth in the tissue.
authors: Graduate Program in Dentistry, Federal University of Pernambuco, Recife, Brazil.|Faculty of Dentistry, Caruaruense Association of Technical and Higher Education, Caruaru, Brazil.
authors: Cláudia C B O
authors: CC
authors: Mota
authors: Graduate Program in Dentistry, Federal University of Pernambuco, Recife, Brazil.
authors: Luana O
authors: LO
authors: Fernandes
authors: Graduate Program in Dentistry, Federal University of Pernambuco, Recife, Brazil.
authors: Renata
authors: R
authors: Cimões
authors: Graduate Program in Dentistry, Federal University of Pernambuco, Recife, Brazil.|Department of Physics, Federal University of Pernambuco.
authors: Anderson S L
authors: AS
authors: Gomes
mesh_terms: D000818:Animals; D003238:Connective Tissue / Q000000981:diagnostic imaging / Q000473:pathology; D003728:Dental Calculus / Q000000981:diagnostic imaging / Q000473:pathology; D003743:Dental Enamel / Q000000981:diagnostic imaging / Q000473:pathology; D003804:Dentin / Q000000981:diagnostic imaging / Q000473:pathology; D004846:Epithelial Attachment / Q000000981:diagnostic imaging / Q000473:pathology; D005583:Fourier Analysis; D005881:Gingiva / Q000000981:diagnostic imaging / Q000473:pathology; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D007180:Incisor / Q000000981:diagnostic imaging / Q000473:pathology; D008334:Mandible / Q000000981:diagnostic imaging / Q000473:pathology; D008853:Microscopy; D008963:Molar / Q000000981:diagnostic imaging / Q000473:pathology; D010514:Periodontal Pocket / Q000000981:diagnostic imaging* / Q000473:pathology; D013552:Swine; D041623:Tomography, Optical Coherence / Q000379:methods*
keywords: Diagnostic imaging; gingiva; optical coherence; periodontal index; periodontics; periodontium; tomography