Background and Aim: Premature birth and low birth weight are regarded as two risk factors for impaired language development. Hence, information about primary period of language development in these children is important for early detection of children&aposs needs during their language development period. The goal of this study was to determine the expressive lexicon size in 18 to 36 month-old premature children with low birth weight and to compare them with their full-term peers.
Methods: In this prospective historical survey, using form II of the MacArthur-Bates Communicative Development Inventories (CDI), expressive lexicon size of 42 premature children with low birth weight who were 18 to 36 month- old and 42 full-term peers in three age groups with six month-intervals is evaluated. Forms were completed individually by mothers of children.
Results: Data analysis showed that the difference in expressive lexicon between the two groups was significant (p=0.025). Nonetheless, in each group the difference in expressive lexicon size between the three age groups was not significant.
Conclusion: The results of this study suggest that expressive lexicon size in premature children with low birth weight was smaller than their full-term matches and the development of lexicon size is delayed in these children. However, by increasing age, these children follow a similar development pattern in terms of lexicon size and eventually catch up with their full term counterparts. This study shows the importance of early intervention to expedite this compensatory mechanism in these children.

Background and Aim: Oral stereognosis is the ability to recognize the objects placed in the mouth this plays a significant role in speech sounds production. Since the children with hearing loss have articulation disorders, this study aimed to clear the relation of hearing loss degrees and oral stereognosis in 5-year-old children.
Methods: In this cross-sectional non-invasive study, 40 children of 5-year-old (30 children with different degrees of hearing loss and 10 normal children) were involved. Oral steriognostic test was done for all of them and the Mann-Whitney U was used for statistical analysis.
Results: There were significant differences between the mean of oral stereognostic ability between the normal children and the children with severe (p<0.01) or profound hearing loss (p=0.05). There was no significant difference between the mean of oral stereognostic ability among the children with moderate, severe and profound hearing loss compared with together. Besides, there was no significant difference between the mean of the time of diagnosis among all of hearing loss and normal children.
Conclusion: The study shows that the children with moderate, severe and profound hearing loss have inefficient oral stereognosis in comparison with the normal children.