Abstract
Background: This present study aims to evaluate the type of relationship between roots of maxillary posterior teeth and maxillary sinus.Methods: Cone beam computed tomography images for 148 patients were evaluated (62 males Vs 86 females). A total of 1052 teeth were examined (518 maxillary premolars and 534 maxillary molars). The relation between roots tips and maxillary sinus floor were classified into four types: type 0, type 1, type 2 and type 3, vertical linear distance was measured and distribution of type of relationship in different age groups were evaluated.Results: Most of single rooted maxillary premolars showed (type 0) relationship with maxillary sinus floor (98.1%) for maxillary first premolars and (69.5%) for maxillary second premolars. In buccal roots of double rooted maxillary first premolars, (type 0) represented (98.7%). While for maxillary second premolars occurred in (50%). Type 0 still the most common appearing type in palatal roots of maxillary first premolars (92%) and in maxillary second premolars it appeared in (45.8%). In maxillary first molars, (type 0) was the most common type which appeared in 43.3%, 39.8% and 38.6% for mesiobuccal, distobuccal and palatal roots respectively. The most common appearing type in single rooted and double rooted maxillary second molars, (type 0) appeared in (50%). In mesiobuccal and distobuccal roots (type 1) appeared in 48.1% and 45.5%, respectively (most common), whereas (type 0) was seen most frequently in palatal roots (39.7%). There was increased appearance of (type 0) in older age group (>45) in maxillary molars roots with statistically significant difference (P-value < 0.001).Conclusions: Most of maxillary premolars, maxillary first molars and palatal roots of maxillary second molars were separated from maxillary sinus floor (type 0). Most of the mesiobuccal and distobaccal roots of maxillary second molars were in contact with the sinus floor (type1).