総義歯が頭部姿勢・頭蓋底角度に及ぼす影響に関する臨床的検討

A Clinical Study to Examine the Effect of Complete Denture on Head Posture/Craniovertical Angle.

抄録

はじめに:

無歯顎患者は、歯槽骨稜の吸収により稜線関係に大きな変化が見られる。この変化は、下顎の上方回転、下顎前突症の増加、そして最終的には自然な頭部姿勢の変化をもたらすことが特徴である。

INTRODUCTION: Edentulous patients show some significant changes in ridge relationship caused by resorption of alveolar ridge. The changes are characterized by an upward rotation of mandible, increase in mandibular prognathism that ultimately results in change of natural head posture.

研究目的:

本研究は、インドの無歯顎患者を対象に、様々な年齢層で総義歯を装着した後、様々な時間間隔で総義歯が頭部姿勢に与える影響を知るために計画されたものである。

AIM: This clinical study was planned to know the effect of complete denture on head posture in different age groups of Indian completely edentulous population, after placement of complete denture at various time intervals.

材料と方法:

対象は、義歯を使用した経験のない完全無歯顎患者である。彼らは2つの年齢群に分けられた。A群（45-60歳）とB群（61-75歳）に分けた。総義歯装着時に頭頂角を特注の定規保護具を用いて測定した．測定は，義歯装着前，義歯装着直後，30分後，24時間後，30日後に行った．

MATERIALS AND METHODS: The sample consisted of completely edentulous patients without previous experience of the dentures. They were divided into 2 age groups: Group A (45-60) and Group B (61-75). During placement of complete denture craniovertical angle was measured with the help of custom made ruler protector device. Readings were taken before denture placement, immediately after denture placement, 30 minutes, 24 hours and 30 days after dentures placement.

結果:

本研究の結果、年齢が高いにもかかわらず、ほとんどの患者（90％）で義歯装着直後に頭部姿勢の変化（伸展）が生じていることがわかった。その後，装着30分後，24時間後の測定においても，測定値は変化しなかった．しかし，30日後の観察では，すべての症例で頭頂角の減少（屈曲）が認められた．両群ともベースラインより頭頂角は大きくなっているが，A群のみ有意な変化が認められた．

RESULTS: The results of this study indicated that in most of the patients (90%) despite their age, change in head posture (extension) occurred immediately after the denture placement. Thereafter reading remains same for measurement at 30 minutes and 24 hours of denture placement. However after 30 days, observation revealed that all the patients showed reduced craniovertical angle (flexion). Even though the values of craniovertical angle remain higher than its baseline in both groups, significant changes were noticed only in Group A.

結論:

全顎無歯顎患者の頭部姿勢は，義歯装着により大きく変化することが明らかになった．30分後と24時間後では，頭部姿勢の伸展はわずかな変化で一定であった．30日後においても，A群では有意な変化が認められたが，B群では有意な変化は認められなかった．

CONCLUSION: Findings revealed that head posture was significantly altered by the placement of dentures in completely edentulous patients. Within the time interval of 30 minutes and 24 hours extension of head posture remained constant with slight variation. Although after 30 days, changes remained significant for group 'A', but no significant changes were observed in the subjects of group 'B'.