The differences among Roth, MBT and Edgewise brackets

Orthodontic brackets are essential components in fixed appliance therapy, used to align teeth by holding archwires. The main differences lie in their "prescriptions" – built-in values for torque (third-order rotation), tip (angulation), and other features.

• Edgewise Brackets: The original "standard" edgewise system introduced by Edward Angle in the 1920s. These have no pre-built torque or tip; all corrections require manual wire bending. Slot sizes are typically 0.022" or 0.018".
• Roth Brackets: A pre-adjusted edgewise system developed by Ronald Roth in the 1970s. Based on Andrews' Straight Wire Appliance (SWA) but with modifications for overcorrection, especially in torque and tip for better finishing and gnathologic goals.
• MBT Brackets: McLaughlin-Bennett-Trevisi system (introduced 1997). A further evolution of Roth, with adjustments for better torque control, reduced tip in anteriors, and lower posterior torque to minimize wire bending and improve sliding mechanics.

Key differences include higher palatal root torque in upper central incisors for MBT (17°) vs Roth (12°) vs Andrews/Edgewise (7°). MBT generally has less tip than Roth. Studies show no clinically significant differences in treatment outcomes between Roth and MBT.

Comparison Table: Key Features

General Differences

Feature	Edgewise (Standard)	Roth	MBT
Type	Non-pre-adjusted (requires wire bends)	Pre-adjusted	Pre-adjusted
Introduced	1920s (Edward Angle)	1970s (Ronald Roth)	1997 (McLaughlin, Bennett, Trevisi)
Common Slot Size	0.022" or 0.018"	0.018" or 0.022"	0.022" (preferred for sliding mechanics)
Torque/Tip	None built-in	Higher torque/tip for overcorrection	Adjusted torque (higher upper incisor, lower posterior), reduced anterior tip
Clinical Outcome	Similar if bends applied correctly	No significant difference vs MBT	No significant difference vs Roth

Example Torque Values (Upper Anterior Teeth)

Torque in Degrees (Palatal Root Torque)

Tooth	Edgewise/Andrews Base	Roth	MBT
Upper Central Incisor	+7°	+12°	+17°
Upper Lateral Incisor	+3° to +7°	+8°	+10°
Upper Canine	-7°	-7°	-7°