Management of mandibular incisors crowding by using passive lower lingual holding arch: a case series and literature review.

Mandibular incisor crowding is a frequently encountered problem in daily orthodontic treatment. Success of the treatment greatly depends on the orthodontist's ability to manage the factors contributing to the existing crowding and implementing the proper interceptive means. The passive lower lingual holding arch (LLHA) helps maintain the position of the permanent first molars after the exfoliation of primary molars and canines. Thus, relieving the mandibular incisor crowding during transitional dentition. Four case reports age ranged from 11-13.5 years old were used to report the effect of using LLHA on mandibular incisor crowding. Little's Irregularity Index (LII) was used to assess the severity of mandibular incisors crowding as well as to compare the severity of the crowding before and after the use of LLHA. Passive LLHA could be considered the appliance of choice for space maintenance during the mixed dentition. Mandibular incisor crowding was reduced as measured by LII after the use of the passive LLHA over a duration of twenty months.

Do the various interceptive treatment modalities improve the position of palatally displaced permanent canines? A meta-analysis.

BACKGROUND: Removal of maxillary primary canines and other interceptive treatment modalities in the mixed dentition have been suggested as methods used to increase the rate of normal eruption of palatally displaced permanent canines (PDCs). However, the information on the overall effect on PDCs' position has been inconclusive. OBJECTIVE: To assess whether this practice improves the position of PDCs and to investigate the quality of the evidence. SEARCH METHODS: Unrestricted searches in 7 databases and manual searching of the reference lists in relevant studies were performed up to June 2022 (Medline via PubMed, CENTRAL, Cochrane Database of Systematic Reviews, Scopus, Web of Science, ClinicalTrials.gov, ProQuest Dissertations, and Theses Global). SELECTION CRITERIA: We looked for data on the positional changes of PDCs (mesial inclination, vertical position, canine crown cusp tip to midline) from randomized controlled trials assessing the various interceptive treatment modalities. DATA COLLECTION AND ANALYSIS: Following study retrieval and selection, relevant data were extracted, and the risk of bias was assessed using the Cochrane Risk of Bias 2 Tool. Exploratory synthesis and meta-regression were conducted using the random effects model and the overall quality of the available evidence was assessed with the Grades of Recommendation, Assessment, Development, and Evaluation approach. RESULTS: Five studies (3 at low risk of bias) were identified, involving 238 individuals, followed for up to 18 months post-intervention with OPG (orthopantomogram) or CBCT (cone-beam computed tomography). Exploratory data synthesis showed that PDCs' position improved more in the extraction sites compared to non-extraction. Analysis of the studies at low risk confirmed the above observations (6- and 12-month). Improvements were observed in patients using headgear after extraction of primary canines compared to extraction alone, but not in patients with double extraction of primary canines and first molars. The quality of available evidence was rated at best as moderate. CONCLUSIONS: Interceptive treatment modalities in the mixed dentition may improve the position of PDCs. However, more studies are necessary in order to determine the clinical significance of the changes. REGISTRATION: PROSPERO (CRD42015029130).