Does residual bone thickness apical to periodontal defect play a major role in maxillary sinus mucous membrane thickness?: A cone‑beam computed tomography‑assisted retrospective study

Abstract

Background: The mucous membrane of the maxillary sinus is very sensitive to foreign bodies
and infections. Any triggering may lead to mucous membrane thickening (MMT). Residual bone
thickness (RBT) is the remaining bone apical to the periodontal defect until the floor of the maxillary
sinus acts as a barrier for the periodontal infections to reach the sinus. The aim of our current
study was to evaluate the minimal RBT to prevent periodontal infection to reach Schneiderian
membrane using cone‑beam computed tomography (CBCT).
Materials and Methods: In this descriptive study, 144 maxillary sinus exposure records of
100 patients were collected retrospectively. Patients with minimum one sinus exposure were
considered. MMT and RBT were calculated with the CBCT assistance. Statistical analysis was done
using Mann–Whitney U‑test , Kruskal–Wallis and Chi‑square test. (P < 0.05) was considered as
statistically significant.
Results: Significant difference (P < 0.001) was observed in MMT among three RBT groups.
Significantly, higher mean MMT was observed with <2 mm and 2–4 mm RBT groups. The prevalence
of MMT with >4 mm group is less (7%) compared to <2 mm group and 2–4 mm RBT groups (91.2%
and 90.2%, respectively). Furthermore, there is no significant difference in MMT between angular
and furcation defects (P = 0.890).
Conclusion: Probability of MMT was increased if RBT is <4 mm. Early detection and prompt
periodontal treatments associated with regenerative procedures can be instituted wherever
possible to improve RBT and to reduce MMT. Further, microbiological studies are required to
confirm the analysis.
Key Words: Cone‑beam computed tomography, furcation defects, maxillary sinus, mucous
membrane, periodontal diseases, periodontitis