Galgali Sushama R, Gontiya Gauri
Department of Periodontics, VS Dental College and Hospital, Bangalore, Karnataka, India.
Indian J Dent Res. 2011 Mar-Apr;22(2):237-41. doi: 10.4103/0970-9290.84294.
Maintenance of gingival health is a key factor for longevity of the teeth as well as of restorations. The physiologic dentogingival unit (DGU), which is composed of the epithelial and connective tissue attachments of the gingiva, functions as a barrier against microbial entry into the periodontium. Invasion of this space triggers inflammation and causes periodontal destruction. Despite the clinical relevance of the determination of the length and width of the DGU, there is no standardized technique. The length of the DGU can be either determined by histologic preparations or by transgingival probing. Although width can also be assessed by transgingival probing or with an ultrasound device, they are either invasive or expensive
This study sought to evaluate an innovative radiographic exploration technique--parallel profile radiography--for measuring the dimensions of the DGU on the labial surfaces of anterior teeth.
Two radiographs were made using the long-cone parallel technique in ten individuals, one in frontal projection, while the second radiograph was a parallel profile radiograph obtained from a lateral position. The length and width of the DGU was measured using computer software. Transgingival probing (trans-sulcular) was done for these same patients and length of the DGU was measured. The values obtained by the two methods were compared. Pearson product correlation coefficient was calculated to examine the agreement between the values obtained by PPRx and transgingival probing.
The mean biologic width by the parallel profile radiography (PPRx) technique was 1.72 mm (range 0.94-2.11 mm), while the mean thickness of the gingiva was 1.38 mm (range 0.92-1.77 mm). The mean biologic width by trans-gingival probing was 1.6 mm (range 0.8-2.2 mm). Pearson product correlation coefficient (r) for the above values was 0.914; thus, a high degree of agreement exists between the PPRx and TGP techniques.
We conclude that the biologic width of the DGU in humans can be measured with the PPRx technique. The values obtained agree with the values obtained by transgingival probing, a technique considered standard so far. Thus, the PPRx technique offers a simple, concise, noninvasive, and reproducible method that can be used in the clinical setup to measure both the length and thickness of the DGU with accuracy.
维持牙龈健康是牙齿及修复体长期留存的关键因素。生理性牙-牙龈单位（DGU）由牙龈的上皮和结缔组织附着组成，其功能是作为防止微生物侵入牙周组织的屏障。该区域受到侵犯会引发炎症并导致牙周组织破坏。尽管确定DGU的长度和宽度具有临床相关性，但目前尚无标准化技术。DGU的长度可通过组织学切片或经龈探诊来确定。虽然宽度也可通过经龈探诊或超声设备进行评估，但这些方法要么具有侵入性，要么成本高昂。
本研究旨在评估一种创新的影像学检查技术——平行轮廓X线摄影术，用于测量前牙唇面DGU的尺寸。
对10名个体采用长锥平行技术拍摄两张X线片，一张为正位投照，另一张为从侧位获得的平行轮廓X线片。使用计算机软件测量DGU的长度和宽度。对这些患者进行经龈探诊（跨龈沟）并测量DGU的长度。比较两种方法获得的值。计算Pearson积差相关系数以检验平行轮廓X线摄影术（PPRx）和经龈探诊获得的值之间的一致性。
采用平行轮廓X线摄影术（PPRx）技术测得的平均生物学宽度为1.72mm（范围为0.94 - 2.11mm），而牙龈的平均厚度为1.38mm（范围为0.92 - 1.77mm）。经龈探诊测得的平均生物学宽度为1.6mm（范围为0.8 - 2.2mm）。上述值的Pearson积差相关系数（r）为0.914；因此，PPRx技术和经龈探诊技术之间存在高度一致性。
我们得出结论，人类DGU的生物学宽度可用PPRx技术测量。获得的值与经龈探诊（一种迄今为止被视为标准的技术）获得的值一致。因此，PPRx技术提供了一种简单、简洁、无创且可重复的方法，可在临床环境中准确测量DGU的长度和厚度。
