That is, when the phoneme /h/ precedes a vowel, /h/ may be realized as a voiceless version of the subsequent vowel. For example the word ⟨hit⟩, /hɪt/ is realized as [ɪ̥ɪt]. H is the eighth most frequently used letter in the English language (after S, N, I, O, A, T, and E), with a frequency of about 4.2% in words. When h is placed after certain other consonants, it modifies their pronunciation in various ways, e.g. for ch, gh, ph, sh, and th. Other languages
In the German language, the name of the letter is pronounced /haː/. Following a vowel, it often silently indicates that the vowel is long: In the word erhöhen (heighten), the second ⟨h⟩ is mute for most speakers outside of Switzerland. In 1901, a spelling reform eliminated the silent ⟨h⟩ in nearly all instances of ⟨th⟩ in native German words such as thun (to do) or Thür (door). It has been left unchanged in words derived from Greek, such as Theater (theater) and Thron (throne), which continue to be spelled with ⟨th⟩ even after the last German spelling reform. In Spanish and Portuguese, ⟨h⟩ ("hache" in Spanish, pronounced [atʃe], or agá in Portuguese, pronounced [aˈɣa] or [ɐˈɡa]) is a silent letter with no pronunciation, as in hijo [ˈixo] (son) and húngaro [ˈũɡaɾu] (Hungarian). The spelling reflects an earlier pronunciation of the sound /h/.
Commonly known as a dental cyst, the periapical cyst is the most common odontogenic cyst. It may develop rapidly from a periapical granuloma, as a consequence of untreated chronic periapical periodontitis.Periapical is defined as "the tissues surrounding the apex of the root of a tooth" and a cyst is "a pathological cavity lined by epithelium, having fluid or gaseous content that is not created by the accumulation of pus. "Most frequently located in the maxillary anterior region, the cyst is caused by pulpal necrosis secondary to dental caries or trauma. Its lining is derived from the epithelial cell rests of Malassez which proliferate to form the cyst. Such cysts are very common. Although initially asymptomatic, they are clinically significant because secondary infection can cause pain and damage. In radiographs, the cyst appears as a radiolucency (dark area) around the apex of a tooths root. Signs and symptoms
Periapical cysts begin as asymptomatic and progress slowly. Subsequent infection of the cyst causes swelling and pain. Initially, the cyst swells to a round hard protrusion, but later on the body resorbs some of the cyst wall, leaving a softer accumulation of fluid underneath the mucous membrane.Secondary symptoms of periapical cysts include inflammation and infection of the pulp causing dental caries. This infection is what causes necrosis of the pulp.Larger cysts may cause bone expansion or displace roots. Discoloration of the affected tooth may also occur. Patient will present negative results to electric and ice test of the affected tooth but will be sensitive to percussion.