Table 3: Proposed classification of maxillary sinus septa and clinical recommendation on management.

Septal Classification	Orientation	Clinical Remarks	Surgeon Degree of Experience Needed
Class I	Medial-lateral (Coronal Plane)	The most common orientation Careful surgical manipulation Difficulty of the case depends on the size and number of septa	Early -Moderate experience
Class II	Anterior-posterior (Sagittal Plane)	Second most common orientation Moderate difficultly based on location Higher incidence of membrane perforation	Moderate experience
Class III	Horizontal or shelf-like (Transverse Plane) off one of the medial or lateral walls	Least common orientation Difficultly based on location /size Higher incidence of membrane perforation	Significant experience
Class IV	A combination of Class I, II, or III.	Common incidence Difficult management with high incidence of membrane perforation. Requires modification of the surgical technique and /or special instrument development	Significant experience /advanced technology