What do systematic reviews say?

Bilateral extraction of compromised mandibular first permanent molars vs Age- and gender-matched non-extraction controls

Bilateral lower first permanent molar extraction was associated with lingual tipping and retrusion of the lower incisors in one case-control study; ungraded.

• Consequences of early extraction of compromised first permanent molar: a systematic review. 2018 All outcomes

  Private clinics (Brazil)
  Normando and Cavacami: lower incisor lingual tipping (1.NB mean 23.2 vs 28.4 degrees, P = 0.004) and retrusion (P = 0.03) after bilateral lower FPM loss. Table 3: Category III, Class C.
  1 study
  GRADE not reported

Bilateral extraction of compromised mandibular first permanent molars vs Age- and gender-matched non-extraction controls

Bilateral lower first permanent molar extraction was associated with counter-clockwise rotation of the occlusal plane and a mild decrease in lower anterior face height in one case-control study; ungraded.

• Consequences of early extraction of compromised first permanent molar: a systematic review. 2018 All outcomes

  Private clinics (Brazil)
  Normando and Cavacami: decreased GnSN angle (P = 0.05), counter-clockwise rotation of the occlusal plane (mean 5.6 vs 12.6 degrees, P = 0.0001), and decreased lower anterior face height (P = 0.048). Table 3: Category…
  1 study
  GRADE not reported

Unilateral cleft lip and palate (UCLP) vs Bilateral cleft lip and palate (BCLP)

Plaque index does not differ significantly between unilateral and bilateral cleft lip and palate (MD -0.13, 95% CI -0.38 to 0.12; ungraded).

• Oral health in patients with cleft lip and palate: a systematic literature review and meta-analysis of periodontal and… 2025 All outcomes

  Clinical dental examination (Thailand and USA)
  MD -0.13 [-0.38, 0.12]
  2 studies · 117 participants
  GRADE not reported

Unilateral extraction of the mandibular first permanent molar vs Bilateral extraction of the mandibular first permanent molars

One study found midline deviation more likely after unilateral than bilateral extraction (OR 11.6; single study; not GRADE-rated).

• Spontaneous space closure after extraction of permanent first molars in children and adolescents: a systematic review… 2024 All outcomes

  Until eruption of the permanent second molar (median follow-up 4.0 years) · University clinics and hospitals in 8 countries (children/adolescents <18 years) · Mandible
  OR 11.6 [1.9, 70.3]
  1 study
  GRADE not reported

Maxillary distraction osteogenesis vs Orthognathic surgery (conventional Le Fort I osteotomy)

It is very uncertain whether maxillary distraction osteogenesis changes long-term skeletal relapse/stability (horizontal movement of A-point) compared with orthognathic surgery (conventional Le Fort I osteotomy) (very low certainty).

• Maxillary distraction osteogenesis versus orthognathic surgery for cleft lip and palate patients 2018 · Cochrane All outcomes

  5 years (long-term)
  MD 4.80 [0.41, 9.19]
  1 study · 16 participants
  Very low

Maxillary distraction osteogenesis vs Orthognathic surgery (conventional Le Fort I osteotomy)

It is very uncertain whether maxillary distraction osteogenesis changes speech: resonance (hypernasality) (deterioration/improvement) compared with orthognathic surgery (conventional Le Fort I osteotomy) (very low certainty).

• Maxillary distraction osteogenesis versus orthognathic surgery for cleft lip and palate patients 2018 · Cochrane All outcomes

  17 months (mean)
  RR 0.11 [0.01, 1.85]
  1 study · 22 participants
  Very low

Maxillary distraction osteogenesis vs Orthognathic surgery (conventional Le Fort I osteotomy)

• Maxillary distraction osteogenesis versus orthognathic surgery for cleft lip and palate patients 2018 · Cochrane All outcomes

  12 months
  SoF (Very Low): Clinical morbidities assessed with questionnaires, follow-up 12 months; risk with orthognathic surgery 3/14; risk with maxillary distraction osteogenesis 3/15; relative effect -; 29 participants (1…
  1 study · 29 participants
  Very low

Maxillary distraction osteogenesis vs Orthognathic surgery (conventional Le Fort I osteotomy)

• Maxillary distraction osteogenesis versus orthognathic surgery for cleft lip and palate patients 2018 · Cochrane All outcomes

  up to 2 years (significant at 3 months)
  Results text (Ungraded; not in SoF): social self-esteem (subset of the Culture-Free Self-Esteem Inventory, CFSEI) - DO participants had lower social self-esteem in the first three months postoperatively, with a…
  1 study · 30 participants
  GRADE not reported

Maxillary distraction osteogenesis vs Orthognathic surgery (conventional Le Fort I osteotomy)

Maxillary distraction osteogenesis showed no clear difference in midfacial soft tissue changes (facial profile landmarks: pronasale,… compared with orthognathic surgery (conventional Le Fort I osteotomy); GRADE not reported.

• Maxillary distraction osteogenesis versus orthognathic surgery for cleft lip and palate patients 2018 · Cochrane All outcomes

  2 years
  Results text (Ungraded; not in SoF): both groups showed notable positive soft tissue changes of the upper lip and nose after maxillary advancement (39 participants). Between-group soft tissue differences at 2 years…
  1 study · 39 participants
  GRADE not reported

Maxillary distraction osteogenesis vs Orthognathic surgery (conventional Le Fort I osteotomy)

It is very uncertain whether maxillary distraction osteogenesis changes velopharyngeal function (complete velopharyngeal closure;… compared with orthognathic surgery (conventional Le Fort I osteotomy) (very low certainty).

• Maxillary distraction osteogenesis versus orthognathic surgery for cleft lip and palate patients 2018 · Cochrane All outcomes

  17 months (mean)
  RR 1.28 [0.65, 2.52]
  1 study · 21 participants
  Very low

Maxillary distraction osteogenesis vs Orthognathic surgery (conventional Le Fort I osteotomy)

It is very uncertain whether maxillary distraction osteogenesis changes psychological status: satisfaction with life (Satisfaction With Life… compared with orthognathic surgery (conventional Le Fort I osteotomy) (very low certainty).

• Maxillary distraction osteogenesis versus orthognathic surgery for cleft lip and palate patients 2018 · Cochrane All outcomes

  2 years
  MD 2.95 [0.14, 5.76]
  1 study · 30 participants
  Very low

Maxillary distraction osteogenesis vs Orthognathic surgery (conventional Le Fort I osteotomy)

It is very uncertain whether maxillary distraction osteogenesis changes maxillary advancement (midfacial hard tissue change; Subspinale… compared with orthognathic surgery (conventional Le Fort I osteotomy) (very low certainty).

• Maxillary distraction osteogenesis versus orthognathic surgery for cleft lip and palate patients 2018 · Cochrane All outcomes

  2 years
  MD 4.40 [0.24, 8.56]
  1 study · 39 participants
  Very low

Maxillary distraction osteogenesis vs Orthognathic surgery (conventional Le Fort I osteotomy)

Maxillary distraction osteogenesis showed no clear difference in speech: nasal emission compared with orthognathic surgery (conventional Le Fort I osteotomy); GRADE not reported.

• Maxillary distraction osteogenesis versus orthognathic surgery for cleft lip and palate patients 2018 · Cochrane All outcomes

  17 months
  RR 3.00 [0.14, 66.53]
  1 study · 22 participants
  GRADE not reported

Pre-radiotherapy extraction of healthy molar teeth vs Conservative treatment (leaving the teeth in place during radiotherapy, with oral health education and disease prevention: oral hygiene, fluoride, diet advice)

The review found no eligible studies for this question.

• Dental extractions prior to radiotherapy to the jaws for reducing post‐radiotherapy dental complications 2013 · Cochrane All outcomes
  no estimate extracted
  0 studies
  No studies found

Pre-radiotherapy extraction of diseased molar teeth vs Conservative treatment (restoration of the teeth and leaving them in place during radiotherapy, with oral health education and disease prevention: oral hygiene, fluoride, diet advice)

The review found no eligible studies for this question.

• Dental extractions prior to radiotherapy to the jaws for reducing post‐radiotherapy dental complications 2013 · Cochrane All outcomes
  no estimate extracted
  0 studies
  No studies found

Pre-radiotherapy extraction of healthy molar teeth vs Conservative treatment (leaving the teeth in place during radiotherapy, with oral health education and disease prevention: oral hygiene, fluoride, diet advice)

The review found no eligible studies for this question.

• Dental extractions prior to radiotherapy to the jaws for reducing post‐radiotherapy dental complications 2013 · Cochrane All outcomes
  no estimate extracted
  0 studies
  No studies found

Pre-radiotherapy extraction of diseased molar teeth vs Conservative treatment (restoration of the teeth and leaving them in place during radiotherapy, with oral health education and disease prevention: oral hygiene, fluoride, diet advice)

The review found no eligible studies for this question.

• Dental extractions prior to radiotherapy to the jaws for reducing post‐radiotherapy dental complications 2013 · Cochrane All outcomes
  no estimate extracted
  0 studies
  No studies found

Pre-radiotherapy extraction of diseased molar teeth vs Conservative treatment (restoration of the teeth and leaving them in place during radiotherapy, with oral health education and disease prevention: oral hygiene, fluoride, diet advice)

The review found no eligible studies for this question.

• Dental extractions prior to radiotherapy to the jaws for reducing post‐radiotherapy dental complications 2013 · Cochrane All outcomes
  no estimate extracted
  0 studies
  No studies found

Pre-radiotherapy dental extraction vs Post-radiotherapy dental extraction

The review found no eligible studies for this question.

• Dental extractions prior to radiotherapy to the jaws for reducing post‐radiotherapy dental complications 2013 · Cochrane All outcomes
  no estimate extracted
  0 studies
  No studies found

Pre-radiotherapy extraction of healthy molar teeth vs Conservative treatment (leaving the teeth in place during radiotherapy, with oral health education and disease prevention: oral hygiene, fluoride, diet advice)

The review found no eligible studies for this question.

• Dental extractions prior to radiotherapy to the jaws for reducing post‐radiotherapy dental complications 2013 · Cochrane All outcomes
  no estimate extracted
  0 studies
  No studies found