Micrognathism is a condition where the jaw is undersized. It is also sometimes called mandibular hypoplasia. [Source: Wikipedia ]

Small mandible
May Cause
Chronic aspiration pneumonia in a child
May Be Caused by
Absence of tongue
Robin sequence
Severe hypoplasia of tongue
Treacher Collins syndrome
Achard syndrome
Acro-cranio-facial dysostosis
Acrofacial dysostosis Miller type
Acrofacial dysostosis Nager type
Acrofacial dysostosis Weyers type
Acrorenal-mandibular syndrome
Agenesis of the corpus callosum - intellectual deficit - coloboma - micrognathia
Aminopterin fetopathy
Aminopterin-fetopathy-like syndrome
Aniridia-Wilms tumor association
Auricular-condylar syndrome
Bifid epiglottis syndrome
Bloom syndrome
Brachmann-de Lange syndrome
Caffey disease
Calabro syndrome
Campomelic dysplasia
Catel-Manzke syndrome
Cephaloskeletal dysplasia
Cerebro-costo-mandibular syndrome
Cerebro-oculo-facio-skeletal syndrome
CHARGE syndrome
Charlie M syndrome
Chondrodysplasia punctata
Chromosome 18:del(18p) syndrome
Chromosome 4p- syndrome
Chromosome 5:del(5p) syndrome
Cockayne syndrome
Cohen syndrome
Cole-Carpenter syndrome
Contractural arachnodactyly
Cowden syndrome
Crane-Heise syndrome
Diastrophic dysplasia
DiGeorge syndrome
Distal arthrogryposis type 2A
Distal limb deficiencies - micrognathia syndrome
Dubowitz syndrome
Dyssegmental dysplasia
Ehlers-Danlos syndrome
Femoral hypoplasia-unusual facies syndrome
Fetal akinesia deformation sequence
Fetal akinesia sequence
Fetal alcohol syndrome
Fetal isotretinoin syndrome
Fetal trimethadione syndrome
Fetal valproate syndrome
FG syndrome
Fontaine syndrome
Frontometaphyseal dysplasia
Fryns syndrome
GAPO syndrome
Gardner-Silengo-Wachtel syndrome
German syndrome
Glossopalatine ankylosis syndrome
Grant syndrome
Hajdu-Cheney syndrome
Hallermann-Streiff syndrome
Hanhart syndrome
Hersh syndrome
Hurst syndrome
Hydrolethalus syndrome
Hypomandibular faciocranial dysostosis
Idaho syndrome
Johanson-Blizzard syndrome
Kaufman oculocerebrofacial syndrome
Klippel-Feil syndrome
Larsen syndrome
Lenz-Majewski dysplasia
Lethal skeletal dysplasia
Mandibuloacral dysplasia
Mandibulofacial dysostosis and tibial hemimelia
Marden-Walker syndrome
Marshall-Smith syndrome
Meckel syndrome
Melnick-Needles osteodysplasty
Mesomelic dysplasia
Mesomelic dysplasia Langer type
Metaphyseal chondrodysplasia Jansen type
Miller-Dieker syndrome
Möbius syndrome
MURCS association
Nager acrofacial dysostosis
Neu-Laxova syndrome
Noonan syndrome
Oculo-auriculo-vertebral spectrum
Ophthalmomandibulomelic dysplasia
Opitz BBBG syndrome
Opitz trigonocephaly syndrome
Orofaciodigital syndrome type 1
Orofaciodigital syndrome type 2
Oromandibular-limb hypogenesis syndrome
Osteolysis with nephropathy
Otopalatodigital syndrome type 2
Otospondylomegaepiphyseal dysplasia
Pallister-Hall syndrome
Pallister-Killian syndrome
Pfeiffer-type cardiocranial syndrome
Postaxial acrofacial dysostosis syndrome Miller type
Potter sequence
Pterygium syndrome
Roberts syndrome
Robin sequence and oligodactyly
Robinow syndrome
Rubinstein-Taybi syndrome
Rutledge syndrome
Schwartz-Jampel syndrome
Seckel syndrome
Short rib-polydactyly syndrome type 1
Short rib-polydactyly syndrome type 2
Silver-Russell syndrome
Smith-Lemli-Opitz syndrome
Splenogonadal fusion - limb defects - micrognathia
Splenogonadal fusion-limb deformity syndrome
Stickler syndrome
TAR syndrome
Trichorhinophalangeal dysplasia type 1
Trichorhinophalangeal dysplasia type 2
Trisomy 13
Trisomy 18
Trisomy 22
Turner syndrome
Velocardiofacial syndrome
Weaver syndrome
Weissenbacher-Zweymüller phenotype
Williams syndrome
Yunis-Varon syndrome
Zellweger syndrome