Table 2 Characteristics of the 6 studies included in the current systematic review
From: Long-term effectiveness of non-surgical open-bite treatment: a systematic review and meta-analysis
| Â | Article | Study Design | Setting | Characteristics of patients | Interventions | No of patients (M/F) | Age in years (SD) | Tx time (SD)a (y) | Follow-up time (SD) (y) | Outcomes | Conclusions | Risk of bias |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
1 | Cozza et al. [37] | rCCT | University; Italy | Presence of thumb-sucking habits before treatment, constricted maxillary arch, negative overbite, fully erupted permanent first molars and permanent incisors, no permanent teeth extracted prior to or during treatment, two consecutive lateral cephalograms of good quality obtained before treatment and again approximately 2 years after the completion of treatment, pre-treatment value for mandibular plane angle (MPA) relative to Frankfort horizontal of 25° or greater | Quad-helix/Crib | Exp: 21 (6/15) Ctr: 21 (10/11) | Exp: 8.4 (1.5) Ctr: 8.6 (0.9) | Exp: 1.5 (0.6) Ctr: total observation time was 3.0 (1.1) years | Exp: 2.0 (NR) Ctr: total observation time was 3.0 (1.1) years | Skeletal Dental Soft tissue | The appliance was effective in correcting dental open bite in 85% of the growing subjects with thumb-sucking habits and dentoskeletal open bites, with a clinically significant improvement in maxillomandibular vertical skeletal relationships | Low |
2 | Defraia et al. [38] | rCCT | University; Italy | Initial mandibular plane angle relative to the Frankfort horizontal (MPA) 25° or greater, 2 consecutive lateral cephalograms of good quality with adequate landmark visualization and minimal or no rotation of the head, taken before treatment and after therapy and retention, no permanent teeth extracted before or during treatment | Open-bite Bionator | Exp: 20 (11/9) Ctr: 23 (10/13) | Exp: 8.3 (0.8) Ctr: 9.1 (1.6) | Exp: 1.5 (NR) Ctr: total observation time was 2.8 (1.1) years | Exp: 1 (NR) Ctr: total observation time was 2.8 (1.1) years | Skeletal Dental Soft tissue | Early treatment e with the open-bite bionator mainly consists of significant improvement in intermaxillary divergence, without favorable effects on the extrusion of posterior teeth | Low |
3 | Ferreira et al. [39] | RCT | University; Brazil | Previous treatment of Angle’s Class I malocclusion and AOB, for 12 months, upper permanent first molars in occlusion, no dental agenesis or permanent teeth loss, no dental extractions | Removable appliance with palatal crib associated with high-pull chincup therapy | Exp: 19 (6/13) Ctr: 19 (2/17) | Exp: (NR) Ctr: (NR) | Exp: 1 Ctr: 1 | 1.3 (NR) | Skeletal Dental Soft tissue | The early open-bite treatment with a removable appliance and palatal crib associated with high-pull chincup therapy provided stability of 95% | High |
4 | Fränkel and Fränkel [40] | rCCT | University; Germany | Hyperdivergent skeletal pattern, large interlabial distance and postural weakness of the orofacial muscles, skeletal development in the craniofacial complex observed in approximately analogous growth periods, from the first stage of the mixed dentition through the pubertal growth spurt | Functional regulators developed by Fränkel | Exp: 30 (NR) Ctr: 11 (NR) | NR | NR |  > 4 (NR) | Skeletal Dental | Some dentofacial deformities in the skeletal open-bite cases were corrected to the average norms and a considerable change in the soft tissue profile occurred | Moderate |
5 | Mucedero et al. [41] | rCCT | University; Italy | No sucking habits, overbite < 0 mm, posterior transverse interarch discrepancy ≥ 3 mm, Frankfort horizontal to mandibular plane angle > 26°, full eruption of first permanent molars and of maxillary and mandibular incisors, no permanent teeth extracted | RME and Posterior bite block and fixed appliances | Exp: 16 (2/14) Ctr: 16 (2/14) | Exp: 8.1 (1.1) Ctr: 8.3 (1.2) | Exp: 1.6 (0.5) Ctr: 1.3 (0.8) | Exp: 3.9 (1.7) Ctr: 3.7 (1.7) | Skeletal Dental | This protocol led to successful and stable positive overbite in 100% of the patients and it was associated with reduced extrusion of maxillary and mandibular molars and a significant improvement in vertical skeletal relationships | Low |
6 | Mucedero et al. [42] | rCCT | University; Italy | Thumb-sucking habit before treatment, negative overbite, constricted maxillary arch as consequence of thumb sucking, full eruption of first permanent molars and permanent incisors, no permanent teeth extracted, postpubertal skeletal maturity at T3 (CS 4–6) | Quad-Helix/crib appliances and fixed appliances | Exp: 28 (11/17) Ctr: 20 (10/10) | Exp: 8.2 (1.3) Ctr: 8.1 (0.4) | Exp: 1.5 (0.4) Ctr: 1.7 (0.4) | Exp: 4.9 (1.3) Ctr: 4.7 (0.6) | Skeletal Dental | In the long term, the use of this appliance led to successful outcomes in about 93% of the patients and it was associated with significant downward rotation of the palatal plane | Low |