Effectiveness of early orthodontic treatment with the twin-block appliance: A multicenter, randomized, controlled trial. Part 1: Dental and skeletal effects

Objective: To compare the short-term skeletal and dental effects of two-phase orthodontic treatment including either a Twin-block or an XBow appliance. Materials and Methods: This was a retrospective clinical trial of 50 consecutive Class II cases treated in a private practice with either a Twin-block (25) or XBow (25) appliance followed by full fixed orthodontic treatment. To factor out growth, an untreated Class II control group (25) was considered.Results: A MANOVA of treatment/observation changes followed by univariate pairwise comparisons showed that the maxilla moved forward less in the treatment groups than in the control group. As for mandibular changes, the corpus length increase was larger in the Twin-block group by 3.9 mm. Dentally, mesial movement of mandibular molars was greater in both treatment groups. Although no distalization of maxillary molars was found in either treatment group, restriction of mesial movement of these teeth was seen in both treatment groups. Both treatment groups demonstrated increased mandibular incisor proclination with larger increases for the XBow group by 3.3u. The Wits value was decreased by 1.6 mm more in the Twin-block group. No sexrelated differences were observed. Conclusions: Class II correction using an XBow or Twin-block followed by fixed appliances occurs through a relatively similar combination of dental and skeletal effects. An increase in mandibular incisor inclination for the XBow group and an increased corpus length for the Twin-block group were notable exceptions. No overall treatment length differences were seen. (Angle Orthod. 2015;85:997-1002.)

Section: Discussionmentioning

confidence: 99%

Dental and skeletal changes in mild to moderate Class II malocclusions treated by either a Twin-block or Xbow appliance followed by full fixed orthodontic treatment

Ehsani¹,

Nebbe²,

Normando

et al. 2015

“…1,[4][5][6][9][10][11][12] The main aim of this study was to compare the effect on treatment response of incorporating a maxillary labial bow in the core CTB appliance design in a matched sample of Class II division 1 subjects. Both appliance designs were effective in producing complete or partial correction of the overjet during the period of observation.…”

Section: Discussionmentioning

confidence: 99%

“…These findings were in broad agreement with those of previous authors. 1,8,9,11,13 A limitation of this study is that it analyzed only short-term effects of the CTB appliance. Long-term follow-up will be required to ascertain whether the reported changes are permanent.…”

Section: Discussionmentioning

confidence: 99%

“…Skeletal change has been shown to account for approximately one-third of the decrease in overjet that is seen in successful cases, with the remainder predominantly maxillary incisor retroclination. 1 Anterior repositioning of pogonion is desirable when mandibular retrognathia contributes to a Class II malocclusion; 2 however, excessive dentoalveolar and rotational changes may limit this anterior translation of the mandible. The original design of the Clark Twin Block (CTB) appliance incorporated a maxillary labial bow.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Use of the Clark Twin Block functional appliance with and without an upper labial bow: a randomized controlled trial

Yaqoob

DiBiase

Fleming

et al. 2012

Objectives: To compare dentoalveolar and skeletal changes in two groups of Class II division 1 patients treated with different designs of Clark's Twin Block (CTB), with (Group 1) or without (Group 2) an upper labial bow. Materials and Methods: A randomized controlled trial was conducted in the Department of Orthodontics at the East Kent Hospitals University NHS Foundation Trust, UK. Sixty-two white subjects (aged 10-14 years at the start of treatment, minimum overjet . 6 mm, molar relationship at least ½ unit Class II) were recruited. Subjects were divided into age-and sex-matched pairs, were randomly allocated to treatment with either appliance design, and were treated for 12 months, at which time additional data were collected. Results: Sixty participants were available for final data collection. The two groups were well matched with respect to age (mean 12.5 years in Group 1; 12.3 years in Group 2). No statistical difference was noted between groups for any dentoalveolar or skeletal variables measured. Both groups experienced a reduction in overjet as a result of maxillary incisor retroclination, mandibular incisor proclination, and forward positioning of the pogonion. Maxillary molar distalization, mandibular molar mesialization, and ANB reduction also occurred in both groups. Conclusions: The addition of a maxillary labial bow to the CTB has no influence on dentoalveolar or skeletal changes, or on rate of overjet reduction, in relation to appliance therapy. (Angle Orthod.

“…This seems to be in line with the recent findings suggesting that only minor benefits can be obtained by early treatment in Class II patients. [3][4][5][6] However, other studies have reported considerably better results after an early intervention. [7][8][9] A recent clinical trial investigated the occlusal effects of the eruption guidance appliance.…”

Section: Introductionmentioning

confidence: 99%

Dentofacial Changes after Orthodontic Intervention with Eruption Guidance Appliance in the Early Mixed Dentition

Keski-Nisula

Salo

et al. 2008

Objective: To evaluate skeletal and dentoalveolar changes induced by the eruption guidance appliance in the early mixed dentition. Materials and Methods: Pre-and posttreatment cephalometric radiographs of 115 consecutively treated children, 62 boys and 53 girls, were compared with those obtained from a control group of 104 children, 52 boys and 52 girls. Pretreatment radiographs were taken at the deciduousmixed dentition interphase (T1) and after full eruption of all permanent incisors and first molars (T2). The mean age of the children in both groups was 5.1 years at T1 and 8.4 years at T2. Results: A significant difference between the groups at T2 was found in the mandibular length, midfacial length, and maxillomandibular differential. The increase in mandibular length was 11.1 mm in the treatment group and 7.2 mm in the control group. No differences were found in measurements of maxillary position or size. There was a significant shift toward a Class I relationship in the treatment group. Labial tipping and linear protrusion of the mandibular incisors was evident in the treatment group at T2. There was no effect on the inclination or position of the maxillary incisors. Conclusions: Occlusal correction was achieved mainly through changes in the dentoalveolar region of the mandible. In addition, the appliance enhanced condylar growth resulting in a clinically significant increase in mandibular length. No effect was observed on maxillary position, maxillary size, inclination or protrusion of the maxillary incisors, or facial height.