Preference of technique for measurement of width of attached gingiva in abutment teeth for fixed dental prosthesis -A retrospective study

Attached gingiva is the distance between the mucogingival junction to a projection of the external surface of the sulcus or the periodontal pocket. There are mainly 3 methods for evaluating attached gingiva functional method (roll technique), the visual method with or without histochemical staining, anesthesia method. This retrospective cross-sectional study was conducted to identify the most commonly used technique for measuring the width of attached gingiva among patients. The study group consists of Adult patients who attended the outpatient Department of Prosthodontics from June 2019-March 2020. 86,000 case sheets were reviewed and sampling was done using simple random sampling. A chi-square test was done to evaluate the correlation between age, gender and Profession with Technique for measurement of Attached gingiva. From the study, we can see that most of the students used Roll technique to find Attached gingiva and some used Balloon technique to find attached gingiva. However, there is no significant correlation between age, gender and Profession with Technique of width of attached gingiva.


INTRODUCTION
Orban irst described attached gingiva as a part of the gingiva which is irmly attached to underlying tooth and bone and is stippled on the surface. The width of attached gingiva is the distance between the mucogingival junction to projection of the external surface of the sulcus or the periodontal pocket (Newman et al., 2012).
Functions of Attached Gingiva is it gives support to marginal gingiva. To help understanding the ability to withstand the functional stresses of mastication  & tooth brushing (Subasree et al., 2016) and provide attachment or a solid base for the movable alveolar mucosa for the action of the cheeks, lips, and tongue (Jain et al., 2017;Ajay et al., 2017). Factors affecting the width of attached gingiva are high frenum attachment, recurrent in lammation (Selvan and Ganapathy, 2016), Malpositioned teeth and Osseous dehiscence.
The methods to locate and measure the mucogingival junction are the functional method (Goldman, 1960;Newman et al., 2012), the visual method with or without histochemical staining, Anesthesia method (Sato, 2000). Lugol's iodine solution is used to demarcate mucogingival junction based on the difference in the glycogen content. The alveolar mucosa differs from keratinized gingiva in its glycogen content, acid phosphatase and nonspeci ic esterase content and an increased amount of elastic iber content resulting in an iodo-positive reaction. The Attached gingiva, which is keratinized, has no glycogen in the most super icial layer and gives an iodo-negative reaction (Bhatia et al., 2015).
Gingiva thickness is generally determined and associated with tooth form . Therefore surrounding soft tissue should carefully be considered when tooth form or size has to be altered.
A study says that periodontal health is altered by wearing temporary partial denture (Jyothi et al., 2017). The successful clinical outcome depends on the thickness of attached gingiva covering it. There are numerous studies that assess the different width of Attached gingiva. There are few studies regarding the assessment of Attached gingiva in Abutment selection.

MATERIALS AND METHODS
This retrospective study was done in a university setup in the Chennai, Southern part of India. Ethical clearance was given from Institutional Human Ethical Committee, Saveetha Dental College and Hospital, SIMATS Chennai. A Database of 86,000 Patients undergoing dental treatment from June 2019 to March 2020 was reviewed out of this 784 reports are taken and patients with no relevant data for 421 reports are omitted because of irrelevant data and 363 samples are taken into consideration and accessed for Preference of technique for measurement of width of attached gingiva in abutment teeth for ixed prosthodontics.
Cross veri ication of data for errors and measures are taken to minimise sampling bias while double blinding the Analyser and Reviewer. The internal and external validity of the sample selected and all the samples are selected based on a simple random sample. Descriptive statistics were used to evaluate technique for width of attached gingiva. The correlation between age, gender and technique were evalu-ated and statistics were carried out using SPSS Software version 2 by IBM. The statistical test used is Chi-Square and Crosstabs data is evaluated.

RESULTS AND DISCUSSION
A total of 363 reports are assessed and in the present study 43% of them preferred the balloon test to see attached gingiva and 55.6% of them preferred the roll test and 5% of them preferred the iodine histo-chemical test Table 1. In the correlation of age and use of technique for measuring width of attached gingiva the results showed that Roll technique is most commonly used in the 36 -65 age group Figure 1. In the correlation of profession and use of technique for measuring width of attached gingiva the results showed that Roll technique is most commonly used by Undergraduates Figure 2.
The results also showed that, in the correlation of sex and use of technique for measuring width of attached gingiva the results showed that Roll technique is mostly done in female patients Figure 3. The p-value obtained while Correlation of Age, Sex and Profession with the technique .874, .269, .511 thus making them insigni icant statistically Table 2.

Figure 1: Bar graph depicting the association between different techniques for inding attached gingiva and different age groups
In Figure 1, X axis represents type of technique used for detecting attached gingiva and Y axis represents count of population. The graph depicts that Roll technique is most commonly used in the 36-65 age group. However, in the 18-35 age group the balloon test was more used. Iodine test was minimally used in any of the age groups. Chi-Square test represents no statistical association between technique and age group having p-value -0.511 (p value>0.05) statistically insigni icant.
In Figure 2, X axis represents type of technique used  In Figure 3, X axis represents type of technique used for detecting attached gingiva and Y axis represents count of population. Correlation of sex with technique for attached gingiva measurement. The graph shows roll technique is most commonly used From the above study, we can see that most of the students preferred Roll test to detect attached gingiva and 156 students preferred balloon test and Iodine test was used by very few members, this could be attributed to the reason that it is time taking and very uncomfortable to the patient. On the other hand Roll test is done in most of the population because it is easy to perform and it is a functional test and assessed by running the probe horizon-tally positioned from the vestibule towards the gingival surface using light force and gives more comfort to patient than other methods. Assessment of the width of attached gingiva is vital in assessing the risk of periodontium. In the assessment of width of the gingiva, the mucogingival junction serves as an important anatomical landmark, which can be demarcated by various methods. As suggested by Fasske and Morgenroth the precise location of this junction can be visualized after staining with stains like Lugol's iodine that aid in determining the exact point at which the keratinization ends (Bhatia et al., 2015).
The width of gingiva increases with age as suggested by authors like Ainamo and Talari (1976); Bokadia et al. (2018); Vincent et al. (1976). The width of attached gingiva varies in different areas of mouth and have been given a range of 1-9mm,1-4mm, and 0-5mm (Bhatia et al., 2015). Variations seen in Bower's study, the widest zone of attached gingiva was found in the incisors and the least in the premolar region irrespective of the method used in the assessment. The assessment of width of attached gingiva in different age groups by VM revealed that the width of gingiva increases with age as suggested by authors like Ainamo and Talari and Vincent et al.
In this study, we can evaluate the preference of technique for evaluating the width of attached gingiva and helps to improve esthetic outcome and pink Esthetics while fabricating the Fixed dental prosthesis. Attached gingiva helps to maintain patient comfort and resistance to mechanical trauma (Vijayalakshmi and Ganapathy, 2016) during oral hygiene procedures and also restores gingival health in the tooth which is to be restored. While restoring crown dentists should be aware of the biology of keratinized Gingiva and methods for increasing the attached gingiva for a successful treatment Outcome (Jain and Dhanraj, 2016). Within the limitations of the study there are modern methods to determine the attached gingiva which are also not included

Limitations
More studies are needed to assess which is the ideal method for detecting width of attached gingiva.

CONCLUSION
Within the limitation of this study it can be inferred that most of the students used roll technique to demarcate attached gingiva followed by balloon technique. Very few have used iodine for detection of attached gingiva. There was no difference in the preference of level of education and the technique used to demarcate the muco-gingival junction. Also there was no preference in the type of test among the different age groups.