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原文題目(出處)： Triad of bilateral duplicated permanent teeth, persistent open apex, and tooth malformation : A case repor. J Contemp Dent Pract 2007;8:94-100
原文作者姓名： Ramin Mostofi Zadeh Farahani, Ali Taghavi Zonuz 通訊作者學校： School of Dentistry at the Tabriz University of Medical
Sciences
報告者姓名(組別)： Intern C組 陸德恩
報告日期： 96-12-10
Abstract：
1. Aim : a case of bilateral multiple impacted supernumerary teeth possible mechanisms of development
2. Background : multiple supernumerary teeth很少見，尤其缺乏引起multiple supernumerary teeth的相關
syndrome or disease時
3. Report : Bilateral multiple supernumerary teeth localized to the mandibular premolar area.
Some of the supernumerary teeth as well as erupted premolars had persistent open apices.
Coronal malformation of the R’t maxillary first premolar was another interesting finding.
這個案例沒有任何相關的症候群
Introduction：
1. 多生牙無論在乳齒或恆齒都是正常齒列外的產物，而且可能發生在任一arch 2. 多生牙有0.8%的機率發生在乳牙，有2.1%的機率發生在恆牙
3. 乳牙的多生牙沒有性別上的差異；恆牙的話，男性比女性有多生牙的機率高 上兩倍
4. 這些多生牙有可能是單一性的或多發性的；單側或雙側；萌發或阻生；單顎 或雙顎
5. 多發性多生牙很少被刊登出來，而多生牙卻沒有伴隨常見的症候群是更為少 見
6. 常見伴隨多生牙的症候群：Gardner’s syndromes, cleidocranial dysostosis 7. 非症候群引起的多生牙好發在下顎，尤其是下顎前牙區域
Case Report Diagnosis
伊朗13 y/o female：
Chief complaint : severe pain in the R’t lower jaw
Clinical examination : several caries on the distal side of R’t lower 2nd premolar hot & cold test Î positive lasting for 30~40 seconds physical examination Î no special abnormalities
Radiographic examination :
a. 5 impacted supernumerary teeth in the mandible b. I.L, I.R and both 2nd premolars are open apex c. the follicular space of these teeth was enlarged
d. II.L and II.R axial rotation toward mesial and complete formed roots
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e. III.L was smaller than other impacted teeth and portion of its root was formed f. R’t maxillary 1st premolar exhibited a marked deviation from normal and greater
M-D width than the left
g. no similar finding in her parents and sister
Treatment
Suggest surgical removal Î the patient decided to retain these tooth and perform periodic follow-ups
Discussion
1. supernumerary teeth的形成目前並沒有定論，但是有許多假說：
a. 隔代遺傳 Î 但異位生長(ectopic development)及單獨發生(solitary occurrence)
否定了這項假說
b. dental lamina hyperactivity Î 最被接受的假說，遺傳似乎最可以解釋這 個現象的產生，
但主要還是環境跟基因的共同影響 所產生的現象
2. 可以由morphology跟location來判定是否是supernumerary teeth：
a. primary dentition : 外型是normal或者conical
b. permanent dentition : conical (small peg-shaped tooth)
tuberculate (barrel-shaped with incomplete root formation and
often paired)
supplemental (duplicated tooth, locate at the end of a tooth
series and seldom impacted) odontoma…等，共17, 18種分類
Î this case：tuberculate type with characteristics bilateral development and incomplete root formation
3. supernumerary teeth的臨床特徵：
a. failure of eruption
b. permanent teeth displacement or rotation c. crowding
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d. abnormal diastema or premature space closure
e. dilaceration, delayed or abnormal root development of the permanent teeth f. cystic formation
g. eruption into nasal cavity h. cleft lip or palate
i. compromised implant site preparation
Î this case：bilateral displacement of mandibular canine and 1st premolars with diastema.
May compromise future placement of implants：
a. delayed eruption or displacement b. associated pathology
c. impediment to orthodontic alignment of permanent teeth d. compromised alveolar bone grafting or implant placement e. spontaneous eruption
以上情形都尚未發生，故先不拔除，保持f/u
Summary
此病例先前沒有報告過，基於對稱性，我們認為可能是在發育過程中有其他因素 造成局部dental lamina hyperactivity
題號 題目
1 Which one of the following pathology does not have supernumerary teeth?
(A) cleft palate
(B) Gardner syndrome
(C) cemento-osseous dysplasia (D) Cleidocranial dysplasia
答案(C) 出處： Oral & Maxillofacial Pathology P.2 & 537 & 567
題號 題目
2 Which one of the following is wrong?
(A) Asian populations have a higher prevalence of hyperdontia than Caucasian.
(B) The prevalence of single-tooth hyperdontia is lower than multiple-tooth hyperdontia.
(C) Accessory tooth of the newborns called natal teeth
(D) The supernumerary teeth in the superior anterior incisor region called mesiodens
答案(B) 出處： Oral & Maxillofcial Pathology P.71
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