Periodontal Bone-Loss, Sinus Pathology, Ethnicity predict Posterior Maxillary Ridge Height

Abstract

Objectives: To study residual ridge dimensions at edentulous maxillary first molar sites and periodontal bone loss among cohorts of partially edentulous Asian Indian(I) and Hong Kong Chinese(C) subjects seeking tooth replacement. Methods: 628 edentulous first molar sites were analyzed retrospectively on Cone Beam Computed Tomography scans of 225 I and 232 C partially edentulous adults seeking tooth replacement. Age, ethnicity, gender, tooth loss, presence or absence of adjacent teeth, categories of periodontal status defined according to radiographic alveolar bone loss (P0: periodontal health, P1: incipient to moderate disease, P2: advanced periodontal disease), sinus membrane abnormalities, alveolar ridge height (RH), widths at 1mm and 3mm from crest (RW1; RW3) and relative position of the bone crest (RR) were determined. RH was categorized into 8 categories; 0-2mm; 2-3mm; 3-4mm; 4-5mm, 5-6mm; 6-7mm; 7-8mm; >8mm. Descriptive statistics, univariate analyses with outcomes; RH categories and RW1, binary logistic regression analyses with outcomes; RH<5mm and RH <8mm, were performed.

Results: Prevalence of P2 status was most frequent in both cohorts(C: 50.4% I: 49.2%). P2 had lowest ridge heights; 13.1% C P2 and 14%I P2 had RH<2mm, sites with both RH<8mm and RW1<6mm occurred at 59%C P2 and 68%I P2. Sinus membrane abnormalities were most frequent in P2. Periodontal status P2 and sinus membrane abnormality increased more than 2 fold the odds (O.R) of both RH<5mm (O.R; 3.117 and 2.035, respectively) and RH <8mm (O.R; 2.592 and 2.823, respectively). Female gender and Indian ethnicity also significantly increased odds of RH<8mm (O.R; 1.843 and 1.985, respectively). Gender (p=0.031) and adjacent tooth status (p<0.001) significantly affected RW1.

Conclusions: Incident advanced periodontal bone loss affected about half among two Asian cohorts seeking tooth replacement and increased odds of lower bone heights in the sub-sinus region, in addition to; sinus membrane abnormality, Indian ethnicity and female gender.