The Difference of the Thickness of Mouthguard Sheet Material after Vacuum Forming Process Depending on the Color of Mouthguard Sheet

Abstract

抄 録 目的：スポーツ時の顎口腔領域の外傷予防には，マウスガードの装着が有効である．本研究は，吸引成形 後のシート各部の厚みについて，色の異なる 2 種のシートを用いて比較検討した． 方法：マウスガードシートに 10 mm 四方の格子を印記し，各格子の厚さをメジャリングディバイス Ⓡ を用 いて測定した．マウスガードシートは白色(MG-W)および紫色(MG-P)のものを用いた．作業用模型 は上顎有歯顎模型をシリコンラバー複製印象材を用いて印象採得後，硬質石膏を注入して作製し，上顎中 切歯切縁で 20 mm，上顎第一大臼歯近心頬側咬頭で 15 mm になるようトリミングしたものを使用した． 加熱条件は，基底面からの垂れ下がり距離が 15 mm のもの(条件 A) ，30 mm のもの(条件 B) ，45 mm のもの(条件 C)の 3 条件とした．2 色のマウスガードシート各部の厚みの違いを t 検定および Wilcoxon 符号付順位和検定を用いて分析を行った． 結果：シートの模型圧接部は，すべての部位で厚みが減少した．前歯部および口蓋部では，すべての加熱 条件において MG-W のほうが MG-P に比較して厚みの変化率が大きかった (p<0.

Shape change in mouthguard sheets during thermoforming – part 2: effect of the anteroposterior position of the model on mouthguard thickness

“…The model was left to dry for over 48 h at about 20.5°C in an air-conditioned room (8)(9)(10)(11)(12)(13)(14)(15)(16). A working model was fabricated using a silicone rubber (Correcsil Ò ; Yamahachi Dental Mfg., Co., Aichi, Japan) impression taken from a maxillary dental model (D16FE-500A-QF; Nissin Dental Products Inc., Kyoto, Japan), into which gypsum (New Plastone Ò ; GC Co., Tokyo, Japan) was poured.…”

“…A laser pointer was fixed to a three-dimensional coordinate measuring machine (192-201; Mitutoyo Co., Kanagawa, Japan) and used to measure the sagging distance (8)(9)(10)(11)(12)(13)(14)(15)(16). A separating medium was applied (at varnish TF; Shofu Inc.) to the model in preparation for pressure molding.…”

“…Measurement points for the thickness of the incisal portion were defined at the left and right central incisor positions as follows: five equally spaced points from the proximal to the distal end of the incisal edge; 10 points on the labial surface (including five equally spaced points from the cervical to incisal edge along a line located one-third of the distance from the proximal edge corresponding to the five points along a line located one-third of the distance from the distal edge). Significance was set to P < 0.05, and the power was set to 0.8 for all analyses (9,(13)(14)(15)(16). Measurements were taken once for each sample and were used in the analysis to determine the mean thickness and to calculate the reduction rate.…”

Influence of continuous use of a vacuum‐forming machine for mouthguard thickness after thermoforming

“…The timing for forming is conventionally judged by the sagging distance, the sheet's softening temperature or the heating time. [13][14][15][16][17] Forming machines have either a single-sided or double sided heating mechanism. 15 Judging the timing from the sagging distance is simple, so it is used for many vacuum-forming machines.…”

“…[13][14][15][16][17] Forming machines have either a single-sided or double sided heating mechanism. Factors that affect shape change during this stage include the heater shape, molding machine heat source 15,22 and the sheet thickness, [23][24][25][26] color, 16,27 and material. 15,[17][18][19] The temperature was constantly higher on the heated surface than on the non-heated surface.…”