Supernumerary teeth in premolar and molar area on CBCT: a pictorial review.

Objective: to build a descriptive classification of premolar and molar supernumerary teeth (ST) when preparing the cone beam computed tomography (CBCT) report. The aim is also to share wide range of CBCT images in the open access publishing model. Material and methods: For our review we systematically searched for articles from PubMed with 1) free full texts on ST in molar and premolar area and using CBCT, and 2) articles providing with information on complications related with the presence of ST in molar and premolar area. We also added to our review studies providing with classic ST classifications in premolar and molar area. Results: We found 29 cases of ST, and we freely illustrated them with 84 figures. We separated our pictorial review in: 1) unilateral ST in the mandible, 2) unilateral ST in the maxilla, 3) unilateral undersized ST, 4) bilateral ST, 5) ST with additional features, and 6) cases with major hyperdontia. Conclusions: we build up the classification matrix for premolar and molar ST with 11 descriptors and 50 boxes. The descriptors were: 1) location if the ST crown in axial view, 2) vertical location of the cusp tip in relation with closest erupted tooth in coronal view, 3) shape, 4) distribution, 5) Position (in relation to normal tooth eruption) in sagittal view, 6) State of eruption of the ST in the sagittal view, 7) Follicle size measurement in sagittal view, 8) External root resorption of adjacent teeth by ST and its location in relation to the long axis of the involved tooth, 9) Internal resorption of ST, 10) Adjacent tooth complication, and 11) Damage to surrounding structures if ST removal. The open access figures from the literature illustrated 11 boxes. With our pictorial review we were able to illustrate 45 out of 50 boxes, and freely provide the readership with the most complete description of ST in premolar and molar area on CBCT than in previously published studies.