Relationship between crown form of upper central incisors and papilla filling in Chinese Han-nationality youth / 北京大学学报(医学版)

Objective:To explore a crown form classification method for upper central incisor which is more objective and scientific than traditional classification method based on the standardized photography technique.To analyze the relationship between crown form of upper central incisors and papilla filling in periodontally healthy Chinese Han-nationality youth.Methods:In the study,180 periodontally healthy Chinese youth (75 males,and 105 females )aged 20 -30 (24.3 ±4.5)years were included.With the standardized upper central incisor photography technique,pictures of 360 upper central incisors were ob-tained.Each tooth was classified as triangular,ovoid or square by 13 experienced specialist majors in prothodontics independently and the final classification result was decided by most evaluators in order to ensure objectivity.The standardized digital photo was also used to evaluate the gingival papilla filling situation.The papilla filling result was recorded as present or absent according to naked eye observation. The papilla filling rates of different crown forms were analyzed.Statistical analyses were performed with SPSS 19.0.Results:The proportions of triangle,ovoid and square forms of upper central incisor in Chinese Han-nationality youth were 31.4% (113 /360),37.2% (134 /360)and 31.4% (113 /360 ), respectively ,and no statistical difference was found between the males and females.Average κvalue be-tween each two evaluators was 0.381.Average κvalue was raised up to 0.563 when compared with the final classification result.In the study,24 upper central incisors without contact were excluded,and the papilla filling rates of triangle,ovoid and square crown were 56.4% (62 /110),69.6% (87 /125 ), 76.2% (77 /101)separately.The papilla filling rate of square form was higher (P =0.007 ).Conclu-sion:The proportion of clinical crown form of upper central incisor in Chinese Han-nationality youth is obtained.Compared with triangle form,square form is found to favor a gingival papilla that fills the inter-proximal embrasure space.The consistency of the present classification method for upper central incisor is not satisfying,which indicates that a new classification method,more scientific and objective than the present one,is to be found.

Preliminary study on measuring interdental papilla height and thickness of the maxillary anterior teeth based on cone-beam computed tomography / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the features of the fill of interdental spaces by gingival papillae and the associated factors.</p><p><b>METHODS</b>Fifteen volunteers with healthy gingiva were involved in this study. The height and thickness on the alveolar crest level of 62 maxillary anterior papilla were measured radiographically with cone-beam computed tomography (CBCT) scans. A standardized periodontal probe with Williams markings was used for measurements of the papilla width on the alveolar crest level.</p><p><b>RESULTS</b>When the papilla was complete fill interdentally, the mean height of papillary tissue on the alveolar crest level (equal to contact point-bone crest) was (3.67 ± 0.51) mm. The mean thickness of papilla on the alveolar crest level was (8.38 ± 0.75) mm. The papilla height had a positive correlation with papilla thickness (r = 0.433, P < 0.001).</p><p><b>CONCLUSIONS</b>The cone-beam computed tomography can be used for clear visualization of the papilla profile and the measurements of papilla height and thickness. Thicker and wider tissue was associated with an increased likelihood of having a complete papilla fill.</p>

Preliminary study on gingival biotype by periodontal probing / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To establish a convenient, objective and applicable method to assess gingival biotype using periodontal probing.</p><p><b>METHODS</b>A total of 66 maxillary anterior teeth from 14 volunteers (6 males, 8 females) with healthy gingiva, aged from 20 to 30 years, were recruited in this study. The gingival biotypes were evaluated by whether or not the outline of the periodontal probe was clear inside the gingiva. Gingival thickness of the cemento-enamel junction (CEJ) in upper anterior teeth was measured by cone-beam CT (CBCT).</p><p><b>RESULTS</b>The method of periodontal probing-assessed gingival biotype had good consistency and repeatability. The result of probing-assessed gingival biotype was consistent with that obtained by CBCT. The mean thickness of gingiva in thin, compromised and thick gingival biotype was (1.02 ± 0.20), (1.28 ± 0.25) and (1.46 ± 0.25) mm. These differences were significant for all three comparisons (P = 0.001, respectively).</p><p><b>CONCLUSIONS</b>Periodontal probing-assessed gingival biotype is a simple, relatively objective and suitable method for clinical examination.</p>

Development of the remote hydraulic pressure control injection / 中国医疗器械杂志

This paper introduced the work principle, execution, use and major characteristics of the remote hydraulic pressure control injection. Using Pascal principle, it is more accurate, convenient, cheap and safe. It could be used in all the fields of the medicine.