Today's orthodontists have a multitude of treatment pathways from which to choose. One-phase or two-phase; extraction, expansion, or fixed distalization; functional, fixed or both appliances; nonsurgical or surgical; space closure or implants, “this-bracket” or “that-bracket”: these are but a few of the choices we may face routinely.

The scientific and professional literature today is packed with more reports than an active specialist in orthodontics can possibly read. For each treatment approach, articles can probably be found that would validate or invalidate the method, depending on one's point-of-view. So where can one turn for sound, unbiased direction? The bad news is

Abstract

This study evaluates the long-term stability of maxillary expansion achieved by widening the inner bow of a facebow, with or without concurrent rapid maxillary expansion (RME) (Haas type), followed by treatment with fixed edgewise appliances. The parent sample included 154 nonextraction patients who started their orthodontic treatment during a defined time period. The exclusion criteria reduced the number of patients to 61 in the cervical-pull facebow group (CFB) and 41 in the RME-CFB group. All subjects were in the late-mixed to early-permanent dentition stage at the start of treatment. Dental casts were measured using a digital imaging system at four different times: start of treatment (T₁), end of active treatment (T₂), end of retention (T₃), and postretention follow up (T₄). The RME-CFB protocol produced a greater increase in maxillary arch width (6.1 mm) than did the CFB protocol (4 mm). The RME-CFB protocol provided greater net maxillary arch perimeter increase than did expansion with an inner bow of a cervical facebow. The RME-CFB group had three mm more arch perimeter 10 years after treatment completion than did the CFB group. The stability of expansion achieved with an inner bow of a facebow was equal to that achieved with a Haas-type RME appliance. Both expansion protocols retained 90% of the initial intermolar expansion 15 years after expansion.

Abstract

The slots of five upper left central incisor brackets from 11 commercially available bracket systems (3M Unitek, Monrovia, Calif: Twin Torque Roth, Clarity MBT, and Victory Series MBT; Dentarum, Pforzheim, Germany: Discovery Roth (0.56 mm) and Elegance Plastic Roth; Forestadent, Pforzheim, Germany: Mini Mono MBT; TP LaPorte, Indiana: Nu-Edge Roth and Mxi Advant-Edge Roth; Ormco Corp., Orange, Calif: Damon II SL Roth; Ortho Organizers, San Marcos, Calif: Elite Mini Opti-MIM Roth and Elite Mini Opti-MIM MBT) were measured in the 0.022-inch (0.5588 mm) dimension. Measurements were taken after operator calibration, and a digital readout was produced. Results indicate that all bracket slots are oversized. Three bracket systems slots (Twin Torque, Clarity, and Mini Mono) were within 5% (±1.08, 1.655, 1.75) of their stated dimensions with essentially parallel slot walls. The Elegance Plastic slot was parallel sided but oversized by 12% (±1.15). The geometry of bracket slots was also variable. The Victory Series slot was slightly divergent with the top oversized by 6% (±1.035). The Nu-Edge slot was divergent and slot top oversized by 14% (±1.32). The Mxi Advant-Edge, Damon II SL, Elite Mini Opti-MIM Roth, and MBT were all convergent, and the base of the Damon slot was oversized by 17% (±1.79). The Discovery bracket was convergent, and the slot base was oversized by 24% (±1.255), which was the largest recorded variance. This bracket also had a 7% difference between the widths of the slot top and the base. Inaccurate machining of bracket slot dimensions and the use of undersized archwires may directly and adversely affect three-dimensional tooth positioning.

Abstract

The treatment of the hyperdivergent phenotype and/or anterior openbite is one of the common problems facing orthodontists. The purpose of this study is to present a new appliance (Molar Intruder) for molar intrusion and to determine its effects in the treatment of anterior openbite. The study group comprised 14 patients (eight girls and six boys), with a mean age of 10 years and 7 months. All presented anterior open bite malocclusions between the second premolars. The study was carried out on lateral head films taken before (T1) and after (T2) molar intrusion. Periapical radiographs, study models, and standard photographs of all the patients were also obtained before and after molar intrusion. The paired sample t- test was used to determine the differences between the parameters. The average treatment time with the Molar Intruder was five months. The mean intrusion of maxillary and mandibular molars was 1.86 mm and 1.04 mm, respectively. Maxillary incisors extruded 0.54 mm with a labial tipping of 1.46° and overbite increased by 4.00 mm. The mandibular plane angle was decreased by 1.57°, and the anterior face height was decreased by 1.86 mm on average. The mandible showed a counterclockwise rotation, the chin moved forward, and the posterior facial height/anterior facial height ratio was increased. Anterior openbites of the patients were significantly rehabilitated at the end of the intrusion period, simplifying further orthodontic treatment.

Lip incompetence resolved by active vertical control in nonsurgical treatment of a protrusion case with vertical maxillary excess

Johnny JL Liaw,

Jae Hyun Park,

Fang Fang Tsai,

Betty MY Tsai, and

Wendy WT Liao