An evaluation of the relationship of gingival biotype and crown morphology of maxillary incisors.
Brief resume of intended work :
6.1 Need for study :
Dentistry today has moved from a philosophy of only treating the pathology concept, to a concept of providing esthetically driven therapy. A lot of factors are instrumental in influencing dental esthetics. Some of them can be enumerated here as crown dimension1, gingival biotype2, gingival zenith3 and tooth position4. These factors need to be considered in planning of restorative, periodontal, prosthetic, orthodontic, and implant therapy. Gingival morphologic characteristics depend on various factors like the dimension of the alveolar process, form and shape of the teeth, and eventual inclination and position of fully erupted teeth.
Studies have investigated relationship of gingival biotype to the tooth form and shape5, 6, although, only a very few studies are done in the Indian population. Hence the need of this study to analyze the relationship of crown morphology with gingival biotype. This may aid immeasurably in treatment planning and providing treatment options in interdisciplinary therapies.
6.2 Review of Literature: The following are some studies in literature that we have reviewed.
Michael Olsson and Jan Lindhe (1991)5- Performed a study to determine periodontal characteristics in varying forms of maxillary central incisors. Crown length and crown width was determined from colored photographs and position of gingival margin was determined clinically. They found that mean crown width/crown length ratio was 0.88 for short wide crown and 0.56 for long narrow crown. They also found that gingival recession was more associated with long narrow crowns as compared to short wide crowns and thus confirmed the hypothesis that an association exists between crown form and periodontal biotype- short wide crowns have thicker gingival biotype and long narrow crowns have thinner gingival biotype.
B. Savitha, K. L. Vandana (2005)7:- Conducted a study to compare the gingival thickness using transgingival probing and an ultrasonographic method. The gingival thickness was measured at midbuccal of attached gingiva and at the base of the papilla by transgingival probing method using UNC15 probe and an ultrasound A-scan machine. They found that both ultrasound and transgingival probing are dependable, but ultrasound is more reliable in the midbuccal region and the transgingival probing method more in the interdental papilla region. They also concluded that the thickness of gingiva varies according to the morphology of teeth with canine having thicker gingiva than the central incisor and central incisor than the lateral incisor.
Yu-Hsiang Chou, Chi Cheng-Tsai, Jen-Chyan Wang, Ya-Ping Ho, Kun-Yen Ho, Chuen Chvyi Tseng (2008)8- Conducted a study to examine the forms of the crowns in the maxillary anterior segment and corresponding gingival characteristics in Taiwanese subjects. Crown width, crown length, gingival angle and the interdental papilla height were determined from diagnostic casts using a calibrated periodontal probe. Gingival thickness and width of keratinized gingiva was measured clinically in the subjects. They found that subjects having narrow teeth showed thinnest gingiva, minimal width of keratinized gingiva; square teeth have similar gingival thickness, medium width of keratinized gingiva, while compound type of teeth have bulkiest gingival thickness and amplest width of keratinized gingiva. They found that Taiwanese subjects showed lower crown width to crown length ratio as compared to Caucasians.
Lucca Gobbato, Teppei Tsukiyama, Paul A Levi, Terrence J. Griffin (2012)9- conducted a study in the Caucasian population to analyze shape of the maxillary central incisors. They took digital photographs and analyzed them with image processing program. Gingival angle, crown length, crown width, contact surface was determined and ratio of crown width to crown length and contact surface to crown length was determined. They found positive correlation between them; greater the gingival angle greater is the crown width to crown length ratio and contact surface to crown length ratio. They also found that teeth with triangular, square and triangular/square shape have contact surface to crown length ratio of 43%, 57% and 43%-57% respectively.
Vishal Anand, Vivek Govila and Minkle Gulati (2012)10- Performed a randomized clinical trial to determine correlation between gingival biotype and gender and tooth shape. Subjects were divided into three categories; slender tooth form, quadratic tooth form and in-between tooth form. Crown width to crown length ratio, gingival width, papilla height, gingival thickness and probing depth of maxillary central incisors were determined. They found that quadratic tooth form has significantly lower papilla height, mean gingival width, gingival thickness and probing depth was significantly greater, as compare to slender tooth form. They also found that gingival biotype depends on gender; males having thicker gingival biotype as compared to females.
6.3 Objectives of the study:
1) To determine the crown width (CW) to crown length (CL) ratio i.e CW/CL of maxillary
2) To determine the proportion of the length of contact surface(CS) to clinical crown length(CL)
i.e CS/CL ratio of maxillary incisors.
3) To determine the gingival biotype on the labial surfaces of the maxillary incisors by using
Biometric A-scan device.
4) To determine a correlation between CW/CL ratio, CS/CL ratio and the gingival biotype of the
Methods and Materials
7.1 Source of data:
The screening of the patients attending out-patient department at Maratha Mandal’s Nathajirao G Halgekar Institute of Dental Science and Research Centre, Belgaum will be done and depending on inclusion and exclusion criteria 30 males and 30 females subjects, in an age group of 18-25 years will be selected. Written informed consent shall be taken from the subjects prior to the examination.
7.2 Methods of collection of data:
Total 60 subjects will be selected consisting of equal number of males and females, in an age group of 18-25 years. Maxillary casts will be prepared of all subjects after taking irreversible hydrocolloid impressions. Crown length (CL) will be measured from gingival zenith to the incisal edge, parallel to long axis of tooth. Crown width (CW) will be measured at the junction of the middle and incisal third of facial surface of tooth. Length of the contact surface (CS) will be determined from most apical to the most incisal point of contact surface area as seen on facial view. All measurements will be taken with a vernier caliper having resolution of 0.02mm.
Gingival thickness will be measured labially on the attached gingiva, midway between the mucogingival junction and free gingival margin using Biometric A-Scan an ultrasound device (Biomedix Optotechnik Pvt. Ltd., Bangalore). Thickness ≥1mm will be consider as a thick biotype and thickness < 1mm as thin biotype.11
The data collected will be subjected to a statistical analysis using 'Karl Pearson’s correlation coefficient' and 'simple linear regression analysis' to show if any relation exist between gingival biotype and CW/CL and CS/CL.
The subjects enrolling in the study will have:
1) Healthy gingiva with probing depth less than or equal to 3 mm
2) Gingival index score of less than or equal to 1
Maratha Mandal’s Nathajirao.G.Halgekar Institute of Dental Sciences and Research Centre, Belgaum
11.5) Head of the Department
Dr. Aarati Nayak
Professor and Head,
Department of Periodontics,
Maratha Mandal’s Nathajirao.G.Halgekar Institute of Dental Sciences and Research Centre, Belgaum
12.1) Remarks of the Principal
DEPARTMENT OF PERIODONTOLOGY
MARATHA MANDAL’s NATHAJIRAO G.HALGEKAR INSTITUTE OF DENTAL SCIENCES AND RESEARCH CENTRE,BELGAUM
INFORMED CONSENT FORM
This Informed Consent Form is for the subjects visiting out-patient department of Maratha Mandal's Nathajirao G. Halgekar Institute of Dental Science and Research Centre, in age limit 18-25 years and who are willing to participate in the research project entitled ' An evaluation of the relationship of gingival biotype and crown morphology of maxillary incisors.'
Name of Principal Investigator: Dr. Pankil K. Shah
Name of Organization: MARATHA MANDAL’S N.G.H. INSTITUE OF DENTAL SCIENCES AND RESEARCH CENTRE,
This Informed Consent Form has two parts:
Information Sheet (to share information about the study with you)
Certificate of Consent (for signatures if you agree to take part)
You will be given a copy of the full Informed Consent Form
PART I: Information Sheet
I, Dr. Pankil k. Shah, am doing my Post Graduation in Periodontology. I am doing a research on ' An evaluation of the relationship of gingival biotype and crown morphology of maxillary incisors.' I am going to give you information and invite you to be part of this research. You do not have to decide today whether or not you will participate in the research. Before you decide, you can talk to anyone you feel comfortable with about the research. There may be some words that you do not understand. Please ask me to stop as we go through the information and I will take time to explain. If you have any questions later, feel free to ask me anytime.
Purpose of the research
The thickness of gums is very important in various dental treatment modalities. It helps the dentist to plan the treatment and to determine various treatment options available for the patients. The reason I am doing this study is to determine relationship between thickness of the gums and the teeth morphologic characteristics. This will help the dentists to plan the treatment, to determine the treatment outcome and various other treatment options available for the patients.
Type of Research Intervention
This research will involve case history recording, examination of oral cavity, recording an impression of upper jaw and measuring the thickness of gums of upper front four teeth with an ultrasound device (Biometric A-scan device).
I wish to include individuals in the age group of 18-25 years with healthy gums. Individuals with any history of trauma to the tooth, orthodontic treatment; individuals who are medically compromised or systemically ill, having cardiac pacemakers, consuming medications affecting periodontal tissue, pregnant, lactating, smokers; individuals having mal-aligned teeth, caries or restorations or crowns, attritions or abrasions or erosions, gingival recessions; are not included in this study.
Your participation in this research is entirely voluntary. It is your choice whether to participate or not. Whether you choose to participate or not, all the services you receive in this institute will continue and nothing will change. You may change your mind later and stop participating even if you agreed earlier.
Procedures and Protocol
After screening examination is done and if you fulfill the selection criteria you will be invited to participate in the research. If you are willing to participate in the research, a case history will be recorded, examination of oral cavity would be done, an impression of your upper jaw will be recorded and thickness of your gums of the upper front four teeth would be measured using an ultrasound device (Biometric A-scan device).
The procedure could take one or two visits of a very short duration.
This investigation entails only an examination, hence by participating in this research, there is no known and anticipated side effects.
By participating in this research, there is no risk of any kind to your health.
There may not be any benefits for you but your participation is likely to help us find the answer to the research question.
You will not be charged for any procedures involved in this study. You will not be given any monetary compensation either.
I assure you the personal information collected from you will be kept confidential. Information about you that will be collected during the research will be put away and no-one but the researchers will be able to see it. Any information about you ,will have a number on it instead of your name. Only the researchers will know about your number.
Sharing the results
The findings of this study will be shared broadly through publications and conferences, scientific conventions. However confidential personal information will not be shared.
Right to refuse or withdraw
You do not have to take part in this research if you don’t wish to do so. You may also stop participating in the research at any time you choose. It is your choice and all your rights will still be respected. Choosing to participate or not will not affect your future treatment at the Centre here in any way. You will still have all the benefits that would otherwise be available at this Centre.
If you have any questions you may ask now or later. If you wish to ask questions later, you may contact the following:
Dr. Pankil K. Shah Contact No. 09925066144
This proposal has been reviewed and approved by ethical committee of the Maratha Mandal’s N.G.H. Institute of Dental Sciences and Research Centre. This is a committee whose task is to make sure that research participants are protected from harm.
PART II: Certificate of Consent
Certificate of Consent
I have been asked to give consent to participate in this study which will involve oral cavity screening, recording of upper jaw impression and measuring the thickness of the gums. I have read the information sheet. I have had the opportunity to ask questions about it and any questions that I have asked have been answered to my satisfaction. I consent voluntarily to participate in this study.
Name of Participant__________________
Signature of Participant___________________
Date ___________________________ (Day/month/year )
I have witnessed the accurate reading of the consent form to the potential participant, and the individual has had the opportunity to ask questions. I confirm that the individual has given consent freely.
Name of witness_____________________ AND Thumb print of participant
Signature of witness ______________________
Statement by the researcher/person taking consent
I have accurately read out the information sheet to the potential participant, and to the best of my ability made sure that the participant understands that the following will be done:
1. Detailed case history of the participant will be recorded.
2. Maxillary impression would be recorded.
3. Gingival biotype would be measured with an ultrasound device.
I confirm that the participant was given an opportunity to ask questions about the study, and all the questions asked by the participant have been answered correctly and to the best of my ability. I confirm that the individual has not been coerced into giving consent, and the consent has been given freely and voluntarily.
A copy of this ICF has been provided to the participant.
Name of Researcher/person taking the consent________________________
Signature of Researcher /person taking the consent__________________________