Teeth vary in size and shape, particularly the wisdom teeth and the upper lateral incisors.
Wisdom teeth may have one, two, three or four roots. They may be rhomboidal, oblong or rounded in shape. Their cusp pattern also presents considerable variation. Grooves lying in the valleys between the cusps may be deep and impenetrable to the tooth brush, making the tooth prone to decay.
Upper lateral incisors may be reduced in overall size, or peg-shaped when the tooth width is extremely reduced. Often, the roots of the affected incisors will be shortened as well. Instead of being flat and shovel shaped like typical incisors, the peg-shaped lateral incisors may present with a rounded outline when seen from the occlusal end (i.e. looking at it from the tip). Orthodontic braces do not bond so well to peg-shaped teeth because the bracket bases do not fit the shape of the these teeth.
Peg-shaped teeth being so small do not blend in well with the adjacent teeth, and present an aesthetic challenge for the dentist or orthodontist. Often, there are gaps next to the peg-shaped incisor teeth. When there are gaps between the front teeth, saliva may be accidentally ejected out during speech. The gaps may be closed using orthodontic braces, Invisalign, composite resin fillings, or veneers, depending on the individual circumstances.