Orthodontic Management of Residual Spaces of Missing Molars: Decision Factors

Abstract

In the daily practice, the orthodontist may be confronted with particular clinical situations with one or more missing teeth. This can complicate the therapeutic plan and influence the choice of possible extractions imposed by treatment requirements. In case of permanent molar absence, making decision becomes even more delicate. The practitioner must use his/her critical sense and clinical common sense to make the right choice between closing and redeveloping the residual spaces. Its choice must meet the patient's expectations and correct the clinical problem without risking overtreatment, or extending duration care. Several factors guide the therapeutic decision, ranging from the patient's age to economic factors, not to mention the technical complexity, therapeutic predictability, and patient comfort, which determine proper compliance and therefore success. In this chapter, we will focus on these decision-making factors by determining the scientific evidence level in terms of success, survival, and patient-centered outcomes (quality of life and functional efficiency).

The impact of the loss of first permanent molars on the duration of treatment in patients treated with orthodontic space closure and without skeletal anchorage

“…Although relatively important in the posterior region, the vertical growth of the face, which can lead to tooth eruption, in young patients rehabilitated with implants can cause a progressive infraocclusion of the implant. [19] On average, treatment time in women was 11.2 months longer than in men (p = 0.045) in the univariate analysis. However, women had an average of 1.37 missing molars, while for men the average was 0.57.…”

“…The loss of the first permanent molars can cause several changes to the occlusion, such as the movement of antagonist and adjacent teeth to the edentulous area, which can lead to occlusal and periodontal problems [19]. In these cases, orthodontists have two treatment options: opening or closing the remaining spaces, and little is known about the duration of orthodontic treatment comparing these cases.…”

“…% PARLoss (n =19) 34.9 (± 13.0) 44.7 (± 17.3) 4.42 (± 3.49) 3.79 (± 3.65) 21.9 (± 5.94) 5.63 (± 2.63) 73.5 (± 11.9) 36.1 months (± 8.45), and 52.5 (± 19.9) when in both arches (n = 10) (Table 2). Regarding dental classification, 24 patients had a Class I canine relationship, with a mean treatment time of 32.0 months (± 19.8), 15 patients were Class II, with a mean time of 33.1 months (± 13.8), and only four patients were Class III, with a mean treatment time of 31.5 months (± 11.1).…”

Molar space closure: To do or not to do?

“…Hence, molar space closure is appropriate in cases of anterior protrusion or crowding. [9,10] If the incisor position is favorable and only pure molar protraction is needed, the treatment time will be lengthened and side effects such as the tilt and rotation of molars are likely.…”

“…[16] Second molar protraction is time-consuming, making this option viable only when the periodontal health of the second molar is not compromised and patients have good oral hygiene. [10] [Figure 4] shows that although no bony defect was observed at the mandibular left second molar before orthodontic treatment, after its protraction toward the extraction socket, a vertical bony defect was found at the mesial root of the mandibular left second molar resulting from the longer treatment time and inadequate oral hygiene in this area.…”