Evaluation of the relationship between maxillary posterior teeth and the maxillary sinus floor using cone-beam computed tomography

Abstract

BackgroundMaxillary posterior teeth have close anatomical proximity to the maxillary sinus floor (MSF), and the race, gender, age, side and presence/absence of adjacent teeth may influence the mean distances between the root apices and the MSF. This study aimed to evaluate both the relationship between the maxillary posterior teeth and MSF, and the influence of adjacent teeth loss on the distance between the maxillary posterior roots and MSF.MethodsCone-beam computed tomography images were collected from 1011 Chinese patients. The relationship between the maxillary posterior teeth and the MSF was divided into three types: Type OS (the root apex extending below/outside the MSF), Type CO (the root apex contacting with the MSF), Type IS (the root apex extending above/inside the MSF). The minimum vertical distances between the maxillary posterior roots apices and the MSF were recorded. The correlations of the distances with gender and age were analyzed. The distances between the maxillary posterior root apices and the MSF with different types of adjacent teeth loss was evaluated.ResultsType OS was the most common relationship of all posterior root apices (P<0.05). Type IS was highest in the palatal roots (PRs) of the maxillary first molars (MFMs) and the mesiobuccal roots (MBRs) of the maxillary second molars (MSMs) (24.8% and 21.6%) (P<0.05). The frequency of Type IS decreased with age except the premolar roots and PRs of the MSMs (P<0.05). The MBRs of the MSMs had the lowest distances to the MSF (0.8 ± 2.5 mm), followed by the distobuccal roots of the MSMs (1.3 ± 2.7 mm) and the PRs of the MFMs (1.4 ± 3.4 mm) (P<0.05). Age was an important influencing factor to the mean distances while gender had little effects. The distance between the maxillary second premolar root apices and the MSF decreased with the absence of adjacent teeth (P<0.05).ConclusionsThe maxillary molars showed greater proximity to the MSF than premolars. Age had significant impacts on the relationship between maxillary posterior roots and MSF. The absence of maxillary first molars will influence the proximity of maxillary second premolar root apices to MSF.

Assessment of Proximity of Maxillary Molars Roots to the Maxillary Sinus Floor in a Sample from the Egyptian Population using Cone-beam Computed Tomography (Hospital Based Study)

“…36 both found that only buccal roots of maxillary 1 st molars had the highest prevalence of being distant from the MSF with the 1 st study conducted on 30 maxillary 1 st molar& 30 maxillary 2 nd molar in 17 CBCT scans, while the last one conducted on 2488 molars in 849 CBCT scans of Turkish subjects. This result was partly contradicting our findings as they found that the palatal root of maxillary 1 st molar had the highest prevalence of being inside the sinus, a finding that was also reported by Gu et al 2018 38 and Estela et al 2016 31 unlike us.…”

“…The highest prevalence of MSF penetration 'type 3' in the current study was recorded for buccal roots of maxillary 2 nd molars and this finding was matching those of Kilic 2010 5 , Pagin 2013 41 , Jung 2012 33 , Asthana 2015 42 & Tian 2016 37 . However , partial correspondence was found between our finding in this point and those of Gu 2018 38 and Estela 2016 31 as both of them found that the palatal root of 1 st maxillary molar is sharing the buccal roots of 2 nd maxillary molars in the highest prevalence of MSF penetration. Yet, Shokri et al 2014 34 reported that both maxillary 1 st molar & 2 nd molar had the highest prevalence of MSF penetration without differentiating the roots affection.…”

“…Comparing this finding to the previously conducted studies, we found only six studies addressing this issue in their results, where a similar inverse correlation between age and maxillary sinus approximation was reported by Didilescu et al 2012 39 in maxillary 1 st molars also which were solely examined in this paper. Furthermore, Tian et al 2016 37 & Gu et al 2018 38 reported the same correlation but not exclusive in maxillary 1 st molars. However, a partial coincidence was found between our results and those of Shokry et al 2016 40 & Ok et al 2014 36 , as the 1 st study concluded that the distance between the buccal roots only of maxillary 1 st molars and the MSF is increased in higher age groups, while the palatal roots of these molars are more commonly approximating MSF in older age subjects.…”

“…Later on, in 2016 Tian et al 37 . utilized the same vertical relationship types of Kilic 35 in Chinese population CBCT, but they named these types by letters (IS), (CO) & (OS) which corresponds to types 1, 2 & 3 respectively, and again the same way of classification was used in 2018 by Gu et al 38 . on CBCT of Chinese population also.…”

“…There was a consensus from all the studies that assessed the vertical relationship between all maxillary posterior teeth (including the premolars) and MSF that the premolars' roots were more distant from the MSF than those of the molars 17,31,32,33,35,38 .…”