Table 1 Summary of the articles on the medical history and clinical characteristics of patients with MRIM

Witt et al., 2014 [1]

8-year-old boy

At the age of 9 months, osteomyelitis of the left femur was successfully treated with antibiotics (cephalosporine, penicillin, lincosamide and glycopeptide).

In both cases, the roots of all four PFMs were malformed, with barely visible or very short roots and narrow appearance of the pulp cavities.

All PFMs extracted.

10.5-year-old girl

Premature delivery (36th week) due to astrocytoma of the pregnant mother was reported. The mother was treated with corticosteroids and breastfed the newborn for two months.

The girl had frequent middle ear infections from 2 years of age, which were treated with amoxicillin and clavulanic acid.

Lee et al., 2014 [2]

N = 12

Male: 6

Female: 6

Aged 4–13 years

Ten of the patients had at age 1 to 2 years meningitis (3), brain injury by dystocia (1), hydrocephalus (1), spina bifida (1), cerebral cyst (1), cephalohematoma (1), or seizure (2).

In all patients, both mandibular PFMs were affected. Seven patients also had affected maxillary PFMs.

Affected PFMs had thin, divergent or short roots and normal contour and surface strength of the crowns.

Mandibular deciduous second molars: 5 patients.

Maxillary incisors (wedge-shaped defect at the cervical portion): 7 patients.

Additional pathology reported: impaction of the PFMs, space loss due to early exfoliation of the deciduous second molar, impaction, hypo-occlusion, dental caries, adjacent tooth eruption disorder, periodontitis, spontaneous pain.

Lee et al., 2015 [5]

6-year-old girl

Premature birth (28th week, birth weight of 1.1 kg) was reported; at 8 weeks, she was diagnosed with perinatal asphyxia.

At the age of 17 months, she was diagnosed with frontal intracerebral hemorrhage and a zygomaticomaxillary fracture.

All PFMs had barely developed roots, partly obliterated pulp cavities, constriction in the crown area, thickened pulpal floor, convex appearance of the furcation floor and normal tooth crown contour.

All PFMs extracted at the age of 9 during orthodontic treatment.

Wright et al., 2016 [3]

N = 30

Male: 18

Female: 12

During the neonatal period, patients had meningomyelocele or sacral dimple (7), meningitis (6), preterm birth (4), or chronic renal disease (4).

In individual patients, the following were reported: meconium aspiration, urinary tract infections, hemiplegia (stroke), cerebral thrombosis, possible cerebrovascular accident, or cerebral palsy with placenta previa.

No major problems were reported in 4 patients.

In all patients, all four PFMs were affected; dysplastic root formation and diminished pulp chamber of the PFMs were observed.

Deciduous second molars:

- all four (14 patients)

- both mandibular (one patient)

Maxillary central incisor (12 patients)

Maxillary and mandibular canine (5 patients)

One patient had all PFMs, all permanent incisors and canines, and two premolars affected.

McCreedy et al., 2016 [6]

8-year-old boy

Sacrococcygeal teratoma was diagnosed prenatally and excised the second day after birth.

In both patients, all PFMs were present with abnormal morphology of the roots (hypoplastic and malformed) and narrow pulp canals but normal contour of the crowns.

Ectopic eruption of the mandibular PFMs.

Ectopic eruption of the permanent maxillary second molars (one patient).

9-year-old girl

Premature birth (28th week) was reported; at six months, she was diagnosed with asthma (treated with fluticasone propionate and albuterol).

Yue and Kim, 2016 [4]

13-year-old-boy

A few days after birth, he was hospitalized for 10–12 weeks due to staphylococcus infection.

Mandibular PFMs had malformed roots (thin, narrow, short) and constricted pulp chambers.

Maxillary central incisors with a wedge-shaped defect at the cervical area.

Brusevold et al., 2017 [7]

N = 6

Aged 8–12 years

1. Born with brain blood clot; epileptic seizures until the age of 7 years

2. Abdominal tumor surgically removed at the age 3 months

3. Hydrocephalus, 3 ventricle shunts; hospitalized several times up to 1.5 years of age due to brain abscesses

4. Acute caesarean section, zygomatic cavernous hemangioma

5. Difficult delivery: tight nuchal cord, birth asphyxia, intracranial hemorrhage; cerebral palsy

6. Seizures and ischemic stroke the fifth day after birth

In all patients, all four PFMs were affected.

Mandibular PFMs: deformed, twisted, narrow, tiny wedge-shaped roots or completely missing roots.

Maxillary PFMs: underdeveloped malformed narrow roots.

Deciduous second molars: both mandibular and a right maxillary had no roots; maxillary left was missing (one patient).

Maxillary permanent incisor with cervical constrictions (four teeth in two patients).

Pain, abscess, fever and/or pus in conjunction with five mandibular PFMs.

Choi et al., 2017 [11]

6-year-old-girl

No history of systemic diseases or medical events at birth.

In both cases, roots of the mandibular PFMs were undeveloped, and roots of the maxillary PFMs were short and thin.

In one case, roots of all PFMs were thin and convergent.

Deciduous second molars: one with a slit-shaped pulp cavity and atypical roots, other three missing (one patient).

Maxillary permanent incisor with wedged-shape enamel defects on the crown (one patient).

In the first case, the mandibular PFMs had to be extracted, and in the second case, two years after extraction of the mandibular PFMs, extraction of the maxillary PFMs had to be performed.

9-year-old-girl

Premature birth (30th week, birth weight of 2.2 kg).

8-year-old-boy

Surgery for myelomeningocele immediately after birth.