THESIS – SYNOPSIS
DEPARTMENT OF CONSERVATIVE DENTISTRY AND
ENDODONTICS
A. B. SHETTY MEMORIAL INSTITUTE OF DENTAL SCIENCES,
DERALAKATTE, MANGALORE.
Rajiv Gandhi University of Health Sciences, Karnataka,
Bangalore.
ANNEXURE II
PROFORMA FOR REGISTRATION OF SUBJECTS FOR DISSERTATION
1. /Name of the Candidate and
Address(in block letters) /
DR. MUSTAFA S BOHRA
POST GRADUATE STUDENT,
DEPARTMENT OF CONSERVATIVE DENTISTRY AND ENDODONTICS,A. B. SHETTY MEMORIAL INSTITUTE OF DENTAL SCIENCES, DERALAKATTE, MANGALORE – 575 018.
2. / Name of the Institution / A. B. SHETTY MEMORIAL INSTITUTE OF DENTAL SCIENCES, DERALAKATTE, MANGALORE – 575 018.
3. / Course of study and subject / MASTER OF DENTAL SURGERY (M.D.S) CONSERVATIVE DENTISTRY AND ENDODONTICS.
4. / Date of admission to course / MAY – 2008
5. / Title of the Topic:
‘‘RIMINERALIZATION OF ENAMEL SUBSURFACE LESION WITH FLUORIDE, CASEIN PHOSPHOPEPTIDE-AMORPHUS CALCIUM PHOSPHATE (CPP–ACP), CPP-ACP WITH FLUORIDE : AN ENERGY DISPERSIVE X-RAY ANALYSIS’’
6.
/ Brief resume of the intended work :
6.1 Need for the study:
The tooth enamel is a microcrystalline porous structure that allows the access of ions into its deeper layers. The presence of an electrically charged hydration layer around enamel crystals is known to be responsible for the capacity of enamel to remineralise non-cavitated lesion with no surgical intervention.1
Changing patterns of dental caries are not only attributed to preventive approaches but also to early interceptive strategies employed, which includes early detection and remineralization of incipient lesions. This is made possible by the use of various remineralizing systems.1
Over the last few decades, fluoride in various form has been proven to reduce caries in both primary and permanent dentitions. In recent years Casein Phosphopeptide Amorphus Calcium Phosphate (CPP-ACP) nano-complexes have also been demonstrated to have anticariogenic and remineralization properties. The combination of CPP-ACP and Fluoride is the most recent one with promising results.
With the advent of all the systems, it is important to quantitatively evaluate the amount of remineralization by different system using non invasive techniques. And find out which system better restores mineral content of original tooth.
Therefore the need of the study is to evaluate remineralizing potential of fluoride, CPP-ACP and CPP-ACP with fluoride.
6.2 Review of Literature:
· This paper compares the experimental techniques utilized to assess the de- or re- mineralization of enamel or dentin in intra oral studies and techniques suitable for direct or indirect mineral quantification. The various measuring techniques considered are micro radiography, iodine absorptiometry, microhardness tests, polarized light, light scattering, iodide permeability and wet chemical analysis.2
· A study was done to examine the effect of CPP –calcium phosphate concentration on remineralization of subsurface lesions. Other solutions were used to examine the effect of increasing pH, which decreased the concentrations free calcium and phosphate ions and increased the relative level of CPP-bound ACP. The remineralizing capacity was greater for the solutions with higher levels of CPP- stabilized free-calcium and phosphate ions. The CPP, by stabilizing calcium phosphate in solution, maintain high concentration gradient of calcium and phosphate ions and ion pairs into the subsurface lesions and thus effect high rates of enamel remineralization.3
· A study was done to evaluate the effect of CPP-ACP paste on demineralization by observing the treated tooth surface using an FE-SEM. The SEM observation revealed different morphological features brought about by the various storage conditions. Demineralization of the enamel and dentin surface was more pronounced with longer test period in the control and negative control specimens. On the other hand, enamel and dentin specimens treated with CPP-ACP paste revealed slight changes in their morphological features. It could be considered that CPP-ACP paste might prevent demineralization of tooth structure.4
· A study was carried out to determine in vitro effect of fluoride on (1) the demineralization of sound human enamel and (2) the progression of artificial caries-like lesions, under relevant oral conditions. Results showed that effect of fluoride on enamel demineralization depends on caries status of enamel surface. Significantly higher concentration of fluoride were required to prevent further demineralization of artificial caries-like lesions than sound enamel.5
· A study was done to determine the ability of CPP-ACP to increase the incorporation of fluoride into plaque and to promote enamel remineralization in-situ. The result showed combination of CPP-ACP is synergistic which is attributable to formation of CPP – stabilized amorphous calcium fluoride phosphate, resulting in increase incorporation of fluoride ions into plaque, together with increased concentrations of bioavailable calcium and phosphate ions.6
· A study was done to investigate the efficacy of CPP-ACP containing paste on remineralization of enamel lesions and to compare its efficacy to that of fluoride-containing toothpaste. The results showed that CPP-ACP decreases lesion depth irrespective of whether or not it was used as a toothpaste or topical coating and CPP-ACP showed higher remineralizing potential when used in combination with fluoridated toothpaste than when used alone.7
· A study was done to determine the effect of ion composition of CPP-ACP and CPP-ACFP solutions on enamel subsurface lesion remineralization in vitro. CPP- bound and free calcium, phosphate and fluoride ion concentration in the solution were determined after ultrafiltration. The ion activities of free ion species present were calculated using an iterative computational program. The mineral deposited in the subsurface lesion was analyzed using transverse micro-radiography and electron microprobe. The result showed that CPP stabilize high concentration of calcium, phosphate and fluoride ions at all pH values. The CPP-ACFP solutions produced greater remineralization than CPP-ACP solutions at pH 5.5 and below. The activity gradient of neutral ion pair CaHPO4 into the lesion was significantly correlated with remineralization and together with HF were identified as important species for diffusion.8
· A Study was done to evaluate the remineralization of incipient enamel lesion by topical application of Casein Phosphopeptide-Amorphus Calcium Phosphate using laser fluorescence and scanning electron microscope. The results of this study showed that laser fluorescent readings of test samples after remineralization were highly significant. A significant number of test samples observed under SEM showed high scores of remineralization.1
· A Study was done to evaluate whether the topical fluoride application (acidulated phosphate fluoride, APF) at high concentration has an additional effect on the control of enamel lesions compared to fluoride dentifrice (FD; low concentration). The frequency of APF treatment on the arrestment of caries lesion and the amount of fluoride deposited on the enamel after application of high and low fluoride concentration was also evaluated. The result showed that change in surface brightness, texture and surface roughness were not detected. Only when topical application was more than three times, surface micro-hardness and fluoride content was increased.9
· A study was done to test the hypothesis that acidic solution undersaturated with respect to enamel and supersaturated with respect to fluorapatite can enhance enamel remineralization by reducing preferential remineralization of the outer lesion and promoting mineral ion penetration. For surface–softened lesion, the extent of remineralization was similar for both solution, although preferential remineralization of the outer lesion was observed with neutral lesion. For subsurface lesions, preferential remineralization of the outer lesion was not observed with either solution. However, the extent of subsurface lesion remineralization by the acidic solution was significantly greater than that observed with the neutral solution.10
6.3 Objectives of the study:
· To quantitatively evaluate and compare the remineralization potential of three remineralizing systems; fluoride, CPP-ACP and CPP-ACP with fluoride, under Scanning Electron Microscopy with EDAX (Energy dispersive X ray analysis) attachment.
7.1 Materials and Methods :
Source of data:
Freshly extracted human molars will be collected from the Dept. of Oral and
Maxillofacial Surgery, A.B. Shetty Memorial Institute of Dental Sciences, Deralakatte,
Mangalore.
7.2 Method of collection of data (including sampling procedure, if any)
Selection of Teeth:
Freshly extracted human molars will be collected, surfaced and stored as per Occupational
Safety and Health Administration (OSHA) regulations.
Exclusion criteria:
Teeth with visible and detectable caries, hypoplastic lesions, stains, white spot lesions,
cracks and erosion are excluded from the study.
Methodology:
· 50 enamel specimens will be prepared from the buccal or lingual surfaces of teeth using a low speed handpiece with diamond disc under water cooling. Each slab will be shaped into a rectangular form (4 x 4 x 2 mm).
· Mineral content of 10 sound enamel specimens will be measured using SEM-EDAX.
· Remaining 40 specimen will be placed in demineralizing solution, containing 2.2mM CaCl2, 2.2mM KH2PO4, 0.05M acetic acid with pH adjusted to 4.4,3 incubated at 37o C for 96 hrs, to produce artificial carries like lesion.
· Mineral content (wt %) of 10 demineralized specimens will be measured using SEM-EDAX
· Specimens will be divided into 3 groups randomly (each group 10 teeth) –
Ø GROUP I – Specimens will be subjected to remineralization using 900 ppm fluoride with NaF
Ø GROUP II – specimens will subjected to remineralization using CCP-ACP
Ø GROUP III – Specimens will be subjected to remineralization using CCP-ACP + Fl
· Each group will be treated with respective remineralizing solutions, followed by incubation in artificial saliva at 37o C, for a period of 28 days.
· Mineral content (wt %) of each remineralized specimen will be measured using SEM -EDAX.
· Results will be compared and statistically analyzed.
7.3 Does the study require any investigations or interventions to be conducted on patients or other humans or animals?
No, this is an in vitro study which does not require any investigations or interventions to
be conducted on patients or other humans or animals.
7.4 Has the ethical clearance been obtained from your institution in case of 7.3?
Not applicable, however a copy of ethical clearance has been enclosed
List of References:
1. Deepika.Pai, Sham S Bhatt, Abhay Taranath, Sharan Sargod, Vinita Pai M. Use of Laser Fluorescence and Scanning Electron Microscope to Evaluate Remineralization of Incipient Enamel Lesions Reminerlized by Topical application of Casein Phosphopeptide Amorphus Calcium Phosphate (CPP-ACP) Containing cream. J Clin Pediatr Dent 2008,32(3):201-206
2. J.Arends and J.J.ten Bosch. Demineralization and remineralization Evaluation Techniques. J Dent Res 1992,71 (special issue),924-928
3. E.C. Reynolds Remineralization of Enamel Subsurface Lesions by Casein Phosphopeptide-stabilized Calcium Phosphate Solutions J Dent Res 1997,76(9): 1587-1595, September
4. Maki Oshiro, Kanako Yamaguchi, Toshiki Takamizawa, Hirohiko Inage, Takayuki watanabe, Atsushi Irokawa, Susumu Ando and Masashi Miyazaki. Effect of CPP-ACP paste on tooth mineralization an FE-SEM study. J Oral Sc,2007,(49),2, 115-120
5. Hajime Yamazaki a,1, Amy Litman b, Henry C. Margolis. Effect of fluoride on artificial caries lesion progression and repair in human enamel: Regulation of mineral deposition
and dissolution under in vivo-like conditions. Arch of oral bio,2007,52,110–120
6. E.C.Reynolds, F.Cai, N.J.Cochrane, P.Shen, G.D.Walker, M.V.Morgan and C.Reynolds. Fluoride and Casein Phosphopeptide - Amorphus Calcium Phosphate. J Dent Res 87(4):344-348,2008
7. VLN Kumar, A Itthagarun, NM King. The effect of casein phosphopeptide-amorphous calcium phosphate on remineralization of artificial caries-like lesions: an in vitro study. Australian Dental Journal 2008; 53: 34–40
8. N.J. Cochrane S. Saranathan F. Cai K.J. Cross E.C. Reynolds. Enamel Subsurface Lesion Remineralisation with Casein Phosphopeptide Stabilised Solutions of Calcium, Phosphate and Fluoride. Caries Res 2008;42:88–97
9. J.J. Jardim, M.A. Pagot, M. Maltz. Artificial enamel dental caries treated with different topical fluoride regimes: An in situ study. J of Dent 2008,(36),396-401
10. H.Yamazaki and H.C.Margolis. Enhanced enamel Remineralization under Acidic Conditions in vitro. J Dent Res 2008,87,(6),569-574
11. Dr Mithra N Hegde, Dr Shishir Shetty, Dr Deepak Pardal. Remineralization of enamel sub-surface lesion using Casein Phosphopeptide Amorphus Calcium Phosphate (CPP-ACP). J Cons Dent 2007,(1),10
12. S.A Mazzaoui, M.F.Burrow, M.JTyas, S.G.Dashper, D.Eakins and E.C.Reynolds. Incorporation of Casein Phosphopeptide-Amorphus Calcium Phosphate into a Glass-ionomer Cement. J Dent Res 2003,82,(1), 914-918
13. R.J.M.Lynch, U.Mony, J.M.ten Cate. The effect of Fluoride at Plaque Fluid Concentrations on Enamel De- and Remineralization at Low pH. Caries Res 2006,40,522-529
14. Amir Azarpazhooh, Hardy Limeback. Clinical Efficacy of Casein derivatives. JADA
2008, july, Vol.139
9. /
Signature of candidate
10. / Remarks of the guide11. / Name & Designation of :
(in block letters)
11.1 Guide / (DR.) SHISHIR SHETTY
READER,
DEPARTMENT OF CONSERVATIVE DENTISTRY AND ENDODONTICS.
11.2 Signature
11.3 Co-Guide (if any)
11.4 Signature
11.5 Head of Department /
PROF. (DR.) MITHRA N. HEGDE
PROFESSOR AND HEAD
DEPARTMENT OF CONSERVATIVE DENTISTRY AND ENDODONTICS.11.6 Signature
12. / 12.1 Remarks of the Principal / Dean
12.2 Signature
PROF. (DR.)B. RAJENDRA PRASAD
STUDY DESIGN