Objective: MELAS (Mitochondrial Encephalomyopathy, Lactic Acidosis and Strokelike episodes) is one of maternally inherited mitochondrial diseases, which are biochemically characterized by a decreased capacity to produce adenosine triphosphate in the cell. The most common cause of MELAS is the m.3243A>G mutation in mitochondrial DNA. It leads to disturbed synthesis of the subunits of the respiratory chain. Clinically MELAS is characterized by multiorgan involvement. Organs with high aerobic energy metabolism are often affected, including nervous system, muscle and heart. Many adult patients are small in height and low in weight. The aim was to find out, whether crown-root ratios describing relative root length of mature permanent teeth in children of m.3243A>G -mothers differ from those in unaffected children.
Subjects and Methods: Subjects were nine children (5 girls, 4 boys) born to mothers harbouring the m.3243A>G mutation. The median age was 11.6 years (range 9.4-15.3 years). The controls were an age- and sex- matched group of school children with normal craniofacial structures. Root-crown ratios of mature permanent teeth were measured on panoramic radiographs by using the method of Lind (1972).
Results: Root-crown ratios of lower left mandibular molars differed between children of mothers with m.3243A>G differed and the control children (p=0.038, Wilcoxon test).
Conclusions: Root-crown ratios of mature permanent teeth in children of mothers with m.3243A>G are mainly similar to those in control children. We suggest that a mitocondrial mutation causing changes in mitochondrial energy metabolism do not affect morphological dental development, which is a strictly genetically determined process.