Non-Cochrane · prognostic · PM39380531
Spontaneous space closure after extraction of permanent first molars in children and adolescents: a systematic review and meta-analysis.
Hamza Blend, Papageorgiou Spyridon N, Patcas Raphael, et al. · European journal of orthodontics · 2024 · PubMed · doi:10.1093/ejo/cjae054
Full textEvery question was extracted from the full text, figures and supplements by two independent LLM extractors, disagreements adjudicated. Rows cite where in the review the value comes from.
Questions
31
current version
GRADE rated
7
No studies
0
Included studies
18
linked below
No studies 0 · 0%Ungraded 24 · 77.4%Very low 0 · 0%Low 7 · 22.6%Moderate 0 · 0%High 0 · 0%
Ungraded means an effect was reported without a GRADE rating; it is not a gap. No studies means the review found nothing to answer the question. The six categories are a display order, not a score.
Review question
| Element | Planned (methods) | Found (results) |
|---|---|---|
| Population | Children/adolescents (<18 years), any sex/ethnicity, with at least one permanent first molar extracted (either jaw) for any reason before emergence of the permanent second molar and followed to complete eruption of the second molar | 1159 patients (n=15 studies; ages 5.5-15.0 y, mean 10.0 y; 45% male) with 2310 permanent second molars assessed |
| Intervention | Extraction of the permanent first molar before eruption of the permanent second molar | Extraction of the permanent first molar (14 retrospective, 1 prospective cohort study) |
| Comparison | Prognostic-factor contrasts (jaw, patient age, second-molar developmental [Demirjian] stage, third molar presence, sex); no untreated/no-extraction control | Prognostic-factor contrasts meta-analyzed: maxilla vs mandible; age bands; Demirjian stages; third molar presence; sex; second-molar inclination |
| Outcomes | Prevalence of spontaneous space closure (primary); eruption, position, inclination and rotation of the second molar and premolars; second-molar developmental stage; third molar presence | Spontaneous space closure prevalence (overall 61.6%, n=13; maxilla 85.3%, n=9; mandible 48.1%, n=11); mandibular second-molar and premolar rotations; pairwise ORs for prognostic factors (14 studies meta-analyzed) |
| Study designs | Any clinical setting | University clinics and hospitals in 8 countries (Belgium, Canada, England, Norway, Palestine, Sweden, Turkey, USA) |
| Timing | Follow-up to complete eruption of the permanent second molar | Median follow-up 4.0 years |
Search date: February 2024. Databases: Five electronic databases searched from inception to February 2024 (database names in Supplementary Appendix 2); reference and citation lists (Google Scholar) hand-searched
Questions and results
Extraction of the permanent first molar vs None (single-group prevalence)
Population: Children and adolescents (<18 years) after extraction of a permanent first molar before eruption of the permanent second molar
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Spontaneous space closure Until eruption of the permanent second molar (median follow-up 4.0 years) · Maxilla In the maxilla, spontaneous space closure occurred in about 85% of cases (9 studies; prevalence not GRADE-rated). Source: Table 3; Fig. 2; Results 'Data synthesis' · same question in other reviews | Prevalence 85.3 [73.7, 92.3] | 9 studies · 665 participants | Ungraded |
Spontaneous space closure Until eruption of the permanent second molar (median follow-up 4.0 years) · Mandible In the mandible, spontaneous space closure occurred in about 48% of cases (11 studies; prevalence not GRADE-rated). Source: Table 3; Fig. 2; Results 'Data synthesis' · same question in other reviews | Prevalence 48.1 [34.5, 62.0] | 11 studies · 1095 participants | Ungraded |
Spontaneous space closure Until eruption of the permanent second molar (median follow-up 4.0 years) · Overall (both jaws) Spontaneous space closure occurred in about 62% of cases overall after permanent first molar extraction (13 studies; prevalence not GRADE-rated). Source: Table 3; Fig. 2; Results 'Data synthesis' · same question in other reviews | Prevalence 61.6 [50.2, 71.9] | 13 studies · 1787 participants | Ungraded |
Extraction of the mandibular permanent first molar vs None (single-group prevalence)
Population: Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar)
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Rotation of the mandibular second premolar Until eruption of the permanent second molar (median follow-up 4.0 years) · Mandible After mandibular first molar extraction, the second premolar was rotated in about 60% of cases (2 studies; very imprecise; not GRADE-rated). Source: Table 3; Results 'Data synthesis' · same question in other reviews | Prevalence 60.0 [10.7, 95.0] | 2 studies · 105 participants | Ungraded |
Rotation of the mandibular second permanent molar Until eruption of the permanent second molar (median follow-up 4.0 years) · Mandible After mandibular first molar extraction, the second molar was rotated in about 77% of cases (2 studies; very imprecise; not GRADE-rated). Source: Table 3; Results 'Data synthesis' · same question in other reviews | Prevalence 76.9 [15.5, 98.4] | 2 studies · 108 participants | Ungraded |
Rotation of the mandibular first premolar Until eruption of the permanent second molar (median follow-up 4.0 years) · Mandible After mandibular first molar extraction, the first premolar was rotated in about 38% of cases (2 studies; very imprecise; not GRADE-rated). Source: Table 3; Results 'Data synthesis' · same question in other reviews | Prevalence 37.8 [0.7, 98.2] | 2 studies · 109 participants | Ungraded |
Extraction of a maxillary permanent first molar vs Extraction of a mandibular permanent first molar
Population: Children and adolescents (<18 years) after extraction of a permanent first molar before eruption of the permanent second molar
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Spontaneous space closure Until eruption of the permanent second molar (median follow-up 4.0 years) · Overall Spontaneous space closure is much more likely in the maxilla than the mandible (OR 7.77; low certainty). Source: Table 4; Table 5 (SoF); Fig. 3 · same question in other reviews | OR 7.77 [4.99, 12.11] 395 [340, 434] per 1000 teeth (more) | 9 studies · 1349 participants | Low Downgraded: risk of bias |
Second molar at Demirjian stage E at extraction vs Second molar at Demirjian stage F-H at extraction
Population: Children and adolescents after extraction of a maxillary permanent first molar (before eruption of the second molar)
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Spontaneous space closure Until eruption of the permanent second molar (median follow-up 4.0 years) · Maxilla In the maxilla, extraction at Demirjian stage E (vs later F-H) increases odds of space closure (OR 4.78; low certainty). Source: Table 4; Table 6 (SoF) · same question in other reviews | OR 4.78 [1.56, 14.66] 73 [32, 87] per 1000 teeth (more) | 3 studies · 252 participants | Low Downgraded: risk of bias |
Age 8-10 years vs Age >10 years
Population: Children and adolescents with maxillary permanent first molar extraction
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Spontaneous space closure Follow-up to complete eruption of the permanent second molar · Maxilla In the maxilla, age 8-10 years was not associated with a statistically significant difference in space closure odds. Source: Table 4; Results, Data synthesis · same question in other reviews | OR >100.00 [0.01, >100.00] | 3 studies | Ungraded Downgraded: risk of bias |
Spontaneous space closure Until eruption of the permanent second molar (median follow-up 4.0 years) · Mandible Population: Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar) In the mandible, extraction before age 8 (vs after 10) increases odds of space closure (OR 5.01; low certainty). Source: Table 4; Table 7 (SoF) · same question in other reviews | OR 5.01 [1.45, 17.30] 226 [73, 283] per 1000 teeth (more) | 2 studies · 15 participants | Low Downgraded: risk of bias |
Extraction at patient age 8-10 years vs Extraction at patient age >10 years
Population: Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar)
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Spontaneous space closure Until eruption of the permanent second molar (median follow-up 4.0 years) · Mandible In the mandible, extraction at age 8-10 (vs after 10) increases odds of space closure (OR 3.32; low certainty). Source: Table 4; Table 7 (SoF) · same question in other reviews | OR 3.32 [1.73, 6.36] 179 [98, 252] per 1000 teeth (more) | 3 studies · 109 participants | Low Downgraded: risk of bias |
Spontaneous space closure Follow-up to complete eruption of the permanent second molar · Maxilla Population: Children and adolescents with maxillary permanent first molar extraction In the maxilla, M2 Demirjian stages A-D were not associated with a statistically significant difference in space closure odds. Source: Table 4; Results, Data synthesis · same question in other reviews | OR >100.00 [0.02, >100.00] | 3 studies | Ungraded Downgraded: risk of bias |
Extraction at patient age 11-12 years vs Extraction at patient age 8-10 years
Population: Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar)
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Spontaneous space closure Until eruption of the permanent second molar (median follow-up 4.0 years) · Mandible In the mandible, extraction at 11-12 vs 8-10 years showed no significant difference in one analysis (OR 0.82; not GRADE-rated). Source: Table 4 · same question in other reviews | OR 0.82 [0.35, 1.88] | 2 studies | Ungraded |
Spontaneous space closure Until eruption of the permanent second molar (median follow-up 4.0 years) · Mandible In the mandible, a second Table 4 analysis suggested lower odds at 11-12 vs 8-10 years (OR 0.29; not GRADE-rated; source labeling ambiguous). Source: Table 4 · same question in other reviews | OR 0.29 [0.11, 0.81] | 2 studies | Ungraded |
M2 Demirjian stages F-G vs M2 Demirjian stages E-D
Population: Children and adolescents with maxillary permanent first molar extraction
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Spontaneous space closure Follow-up to complete eruption of the permanent second molar · Maxilla In the maxilla, M2 Demirjian stages F-G were not associated with a statistically significant difference in space closure odds. Source: Table 4; Results, Data synthesis · same question in other reviews | OR >100.00 [0.01, >100.00] | 3 studies | Ungraded Downgraded: risk of bias |
Spontaneous space closure Until eruption of the permanent second molar (median follow-up 4.0 years) · Mandible Population: Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar) In the mandible, mean patient age was not significantly associated with space closure odds (OR 0.59 per year; not GRADE-rated). Source: Table 4 · same question in other reviews | OR 0.59 [0.20, >100.00] | 3 studies | Ungraded |
Male sex vs Female sex
Population: Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar)
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Spontaneous space closure Until eruption of the permanent second molar (median follow-up 4.0 years) · Mandible In the mandible, sex was not significantly associated with space closure (OR 1.38; not GRADE-rated). Source: Table 4 · same question in other reviews | OR 1.38 [0.37, 5.14] | 2 studies | Ungraded |
Second molar at Demirjian stage A-D at extraction vs Second molar at Demirjian stage F-H at extraction
Population: Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar)
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Spontaneous space closure Until eruption of the permanent second molar (median follow-up 4.0 years) · Mandible In the mandible, earlier Demirjian stage A-D (vs F-H) increases odds of space closure (OR 3.11; low certainty). Source: Table 4; Table 7 (SoF) · same question in other reviews | OR 3.11 [1.25, 7.72] 202 [49, 285] per 1000 teeth (more) | 3 studies · 95 participants | Low Downgraded: risk of bias |
Second molar at Demirjian stage A-D at extraction vs Second molar at Demirjian stage G-H at extraction
Population: Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar)
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Spontaneous space closure Until eruption of the permanent second molar (median follow-up 4.0 years) · Mandible In the mandible, Demirjian stage A-D vs G-H was not significantly associated with space closure (OR 2.75; not GRADE-rated). Source: Table 4 · same question in other reviews | OR 2.75 [0.50, 15.10] | 3 studies | Ungraded |
Second molar at Demirjian stage E at extraction vs Second molar at Demirjian stage F-H at extraction
Population: Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar)
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Spontaneous space closure Until eruption of the permanent second molar (median follow-up 4.0 years) · Mandible In the mandible, extraction at Demirjian stage E (vs later F-H) increases odds of space closure (OR 3.81; low certainty). Source: Table 4; Table 7 (SoF) · same question in other reviews | OR 3.81 [1.85, 7.83] 226 [125, 286] per 1000 teeth (more) | 3 studies · 94 participants | Low Downgraded: risk of bias |
Second molar at Demirjian stage E-F at extraction vs Second molar at Demirjian stage G-H at extraction
Population: Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar)
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Spontaneous space closure Until eruption of the permanent second molar (median follow-up 4.0 years) · Mandible In the mandible, Demirjian stage E-F vs G-H was not significantly associated with space closure (OR 4.44; not GRADE-rated). Source: Table 4 · same question in other reviews | OR 4.44 [0.43, 46.10] | 3 studies | Ungraded |
Second molar at Demirjian stage F-G at extraction vs Second molar at Demirjian stage D-E at extraction
Population: Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar)
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Spontaneous space closure Until eruption of the permanent second molar (median follow-up 4.0 years) · Mandible In the mandible, Demirjian stage F-G vs D-E was not significantly associated with space closure (OR 0.68; not GRADE-rated). Source: Table 4 · same question in other reviews | OR 0.68 [0.28, 1.66] | 4 studies | Ungraded |
Second molar distally inclined at extraction vs Second molar upright at extraction
Population: Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar)
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Spontaneous space closure Until eruption of the permanent second molar (median follow-up 4.0 years) · Mandible In the mandible, distal inclination of the second molar vs upright was not significantly associated with space closure (OR 1.18; not GRADE-rated). Source: Table 4 · same question in other reviews | OR 1.18 [0.43, 3.21] | 3 studies | Ungraded |
Second molar mesially inclined at extraction vs Second molar upright at extraction
Population: Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar)
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Spontaneous space closure Until eruption of the permanent second molar (median follow-up 4.0 years) · Mandible In the mandible, mesial inclination of the second molar vs upright was not significantly associated with space closure (OR 0.68; not GRADE-rated). Source: Table 4 · same question in other reviews | OR 0.68 [0.27, 1.71] | 3 studies | Ungraded |
Mandibular third molar present vs Mandibular third molar absent
Population: Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar)
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Spontaneous space closure Until eruption of the permanent second molar (median follow-up 4.0 years) · Mandible In the mandible, presence of the third molar increases odds of spontaneous space closure (OR 2.28; low certainty). Source: Table 4; Table 7 (SoF); Fig. 4 · same question in other reviews | OR 2.28 [1.67, 3.09] 195 [126, 256] per 1000 teeth (more) | 4 studies · 467 participants | Low Downgraded: risk of bias |
Dental crowding present vs Dental spacing present
Population: Children and adolescents (<18 years) after extraction of a permanent first molar before eruption of the permanent second molar
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Spontaneous space closure Until eruption of the permanent second molar (median follow-up 4.0 years) · Overall One study found space closure more likely with crowding than spacing (OR 5.9; single study; not GRADE-rated). Source: Results 'Data synthesis' (Supplementary Appendix 8) · same question in other reviews | OR 5.9 [1.3, 27.7] | 1 study | Ungraded |
Second molar at Nolla developmental stage 6-7 at extraction vs Second molar at later Nolla stages at extraction
Population: Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar)
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Spontaneous space closure Until eruption of the permanent second molar (median follow-up 4.0 years) · Mandible One study found mandibular Nolla stage 6-7 associated with better space closure (OR 55.1; single study; not GRADE-rated). Source: Results 'Data synthesis' (Supplementary Appendix 8) · same question in other reviews | OR 55.1 [3.0, at least 100.0] | 1 study | Ungraded |
Unilateral extraction of the mandibular first permanent molar vs Bilateral extraction of the mandibular first permanent molars
Population: Children and adolescents after extraction of a mandibular permanent first molar (before eruption of the second molar)
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Midline deviation of the mandibular arch Until eruption of the permanent second molar (median follow-up 4.0 years) · Mandible One study found midline deviation more likely after unilateral than bilateral extraction (OR 11.6; single study; not GRADE-rated). Source: Results 'Data synthesis' (Supplementary Appendix 8) · same question in other reviews | OR 11.6 [1.9, 70.3] | 1 study | Ungraded |
Comparison
| Outcome | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Spontaneous space closure Maxilla: M2 Demirjian A-D vs G-H | OR >100.00 | 1 study | Ungraded |
Spontaneous space closure Mandible: M2 Demirjian E-F vs G-H | OR 42.0 | 1 study | Ungraded |
Spontaneous space closure Maxilla: M2 Demirjian E-F vs G-H | OR 8.0 | 1 study | Ungraded |
Included primary studies 18
Open as a trial list| Study | Also included by | Outcomes it informs here | Trial PICO | Results |
|---|---|---|---|---|
| Patel 2017 matched by author and year (probable) | 1 other review | not stated | not extracted yet | not extracted yet |
| Rahhal 2014 matched by author and year (probable) | 1 other review | not stated | not extracted yet | not extracted yet |
| Aldahool 2024 matched by author and year (probable) | this review only | not stated | not extracted yet | not extracted yet |
| Aldahool 2024 Spontaneous space closure in patients treated with early extraction of the first permanent molar: a retrospective cohort study using… PMID:38381800 | this review only | not stated | not extracted yet | not extracted yet |
| Brusevold 2022 matched by author and year (probable) | this review only | not stated | not extracted yet | not extracted yet |
| Brusevold 2022 Extraction of first permanent molars severely affected by molar incisor hypomineralisation: a retrospective audit. PMID:34170497 | this review only | not stated | not extracted yet | not extracted yet |
| Canpolat 2020 matched by author and year (probable) | this review only | not stated | not extracted yet | not extracted yet |
| Ciftci 2021 matched by author and year (probable) | this review only | not stated | not extracted yet | not extracted yet |
| Ciftci 2021 Spontaneous space closure following the extraction of the first permanent mandibular molar. PMID:34657009 | this review only | not stated | not extracted yet | not extracted yet |
| Ertugrul 2022 matched by author and year (probable) | this review only | not stated | not extracted yet | not extracted yet |
| Gaudreau 2022 matched by author and year (probable) | this review only | not stated | not extracted yet | not extracted yet |
| Jalevik 2007 matched by author and year (probable) | this review only | not stated | not extracted yet | not extracted yet |
| Lenaker 2022; 2023 Radiographic Evaluation of Predictors for Spontaneous Space Closure and Supereruption After the Loss of Permanent First Molars in Yup'ik… PMID:37381127 | this review only | not stated | not extracted yet | not extracted yet |
| Mouroutsou 2018 matched by author and year (probable) | this review only | not stated | not extracted yet | not extracted yet |
| Nordeen 2022 Radiographic Evaluation of Permanent Second Molar Substitution After Extraction of Permanent First Molar: Identifying Predictors for… PMID:35484777 | this review only | not stated | not extracted yet | not extracted yet |
| Patel 2017 Radiographic prognostic factors determining spontaneous space closure after loss of the permanent first molar. PMID:28364895 | this review only | not stated | not extracted yet | not extracted yet |
| Serindere 2019 matched by author and year (probable) | this review only | not stated | not extracted yet | not extracted yet |
| Thilander 1970 Orthodontic sequelae of extraction of permanent first molars. A longitudinal study. PMID:5287509 | this review only | not stated | not extracted yet | not extracted yet |
Overlap with other reviews
Reviews that include the same primary studies are not independent evidence. Shared counts match studies by PMID, DOI or NCT, and otherwise by author and year (a probable match).