Treatment of impacted or retained second molars with the miniscrew-supported pole technique: a prospective follow-up study

Abstract

Background Eruption disturbances of permanent molars are uncommon; however, it is important to treat them as soon as they are diagnosed. The main objective was to analyze the effectiveness of the “miniscrew-supported pole technique,” a surgically assisted orthodontic procedure to force the eruption of impacted/retained second molars (M2s) when there are indicators of complex molar inclusion. An observational prospective study was carried out during a 2-year period. Sociodemographic, clinical and low-dose scanner variables were taken at baseline (T0). Follow-up variables (T1) were the time between surgery and tooth eruption, radiographic measurements, debonding of buttons, failure rate of miniscrews and success rate of eruption. Results A total of 21 patients (mean age of 13.9 years) with 24 retained/impacted M2s were recruited; 13 molars were maxillary (54.2%) and 11 (45.8%) were mandibular. Six (25%) were impacted molars and 18 (75%) primarily retained. At T0, molar angulation was mesial in six molars (25%), distal in five molars (20.8%) and 13 molars were vertically positioned (54.2%). Infraocclusion degree was moderate in four (16.7%) molars and severe in 20 (83.3%). Only three (12.5%) third molars were removed due to lack of space. All M2s managed to erupt, achieving a success rate of 100%; however, two molars of the same patient did not achieve occlusion. The period of eruption after surgery was 126.8 (117.3) days. Anatomical radicular alteration was the only variable independently related to a longer time of treatment (p = 0.027). Conclusions The pole technique, using one mesial miniscrew and simple orthodontic mechanics, applies forces that succeed in erupting complicated retained/impacted M2s in a short period of time and with a low failure rate.

Mandibular Second Molar Impaction: Introducing a Novel and Validated 3D Classification System

“…In terms of therapeutic approaches, many impacted M2Ms underwent successful treatment through a combination of surgical intervention and orthodontic traction [1,6,7,12,16,19,[22][23][24][25][26]. M2M impaction can show a partial or total mucosal coverage, or a bone impaction for the most severe cases.…”

Uprighting horizontally impacted third molars by super-elastic nickel-titanium wire in patients with an extracted first molar

“…Fear of anchorage control in uprighting mesially impacted second or third molars leads to the widespread use of TADs in the uprighting process. For example, Lorente et al [10,21] utilized miniplates in the retromolar region as skeletal anchorage for treating second molar impactions. However, it must be noted that miniplates have high rates of failure and mobility, difficulty with regards to maintaining oral hygiene, discomfort because of the size of the device in the retro-molar region [22].…”

“…Although the widespread use of skeletal anchorage over the last decade has provided orthodontists with precise and efficient anchorage, several complications have been reported in the literature, such as the fracture of mini-screws, root perforation and the death of pulp tissue in adjacent teeth [9]. Furthermore, such placement of skeletal anchorage units in the retromolar region may bring about much discomfort and unwanted side effects, such as irritation and swelling of the mucosa, pain, infection, blood vessel injury, and fracture of the mini-screws during placement [10,11]. In addition, the insertion of skeletal anchorage units in the retromolar region involves considerable surgical procedures which represent a demanding task for orthodontists [12].…”