Bruxism more than the periodontal ligament is biologically designed to handle, and so inflammation may result. A tooth may become sore to bite on, and further, tooth wear may reduce the insulating width of enamel and dentin that protects the pulp of the tooth and result in hypersensitivity, e.g. to cold stimuli. The relationship of bruxism with temporomandibular joint dysfunction (TMD, or temporomandibular pain dysfunction syndrome) is debated. Many suggest that sleep bruxism can be a causative or contributory factor to pain symptoms in TMD. Indeed, the symptoms of TMD overlap with those of bruxism. Others suggest that there is no
Habitual aspect Italian, and Portuguese do not have a grammatical form that is specific to the habitual aspect. In the past tense, they have a form called the imperfect, which combines the past tense with the imperfective aspect; it is used to indicate that a past ongoing process was habitual or continuous. Cantonese, a Sinitic language, has a dedicated particle to express the habitual aspect, 開 "hoi1", which follows the verb. This is unlike Mandarin and some other Sinitic languages, which have no grammatical indicators of the habitual aspect, but may express habituality via circumlocution. Habitual aspect In linguistics, the aspect of