Dental and alveolar consonants are usually represented by the same symbol. Otherwise I use a colon as the standard IPA length mark. This will result in some inconsistencies where a vowel symbol lacks a form with a circumflex. If you're using IE 5.x click here to see the chart using a phonetic font. See the Transcription chart below for further details of the first two.
Vowels pattern in a number of ways.
Front vowels are usually unrounded, while non-low back vowels are usually rounded. Front rounded vowels are more common than back, unrounded ones. Central vowels usually pattern with back vowels. Such languages tend to have large numbers of vocalic allophones which are conditioned by adjacent consonants. If a representation is faithful to what constitutes the output of a language, it is said to be well-formed.