The presence of a prosthesis may lead to the underestimation of periodontal probing depth (PPD), according to a study summarised in the latest issue of the EFP’s JCP Digest.
A cross-sectional study, carried out at the implant-maintenance unit of the University of Barcelona in Spain, evaluated PPD differences with and without prosthesis in single posterior implants without interproximal bone loss. A secondary aim was to evaluate the effect of diagnosis (healthy vs. mucositis) and implant location (premolar vs. molar) on differences in PPD.
Probing depth was measured before and after the temporary removal of the prosthesis. The study, summarised as JCP Digest 88, found that the PPD values were identical in 23.6% of sites, were overestimated by up to 1mm in 12.9% of sites, and were underestimated in 63.5% of sites, with the underestimation exceeding 2mm in 38% of the sites.
Researchers concluded that the presence of a prosthesis may alter the PPD recording, leading to a mean underestimation of -1.15mm (±1.24mm). Furthermore, this underestimation may be more pronounced in healthy implants compared to implants with mucositis.
They also found that the implant location (molar/premolar) did not affect PPD measurements whether with or without prosthesis and said that future studies were warranted to evaluate the possible impact of the prosthesis on PPD measurements over time as well as on implants where bone loss is already present.
The research was summarised for JCP Digest by students of the EFP-accredited postgraduate programme in periodontology at Rothschild Hospital, Paris University in Paris, France.