Comparison of Proximal Contacts and Contours in Class II Composite Restoration With Pre-cured Composite Inserts Versus Contact Making Instrument Technique. A Randomized Control Clinical Trial.

Study design : randomized control clinical trial with three intervention arms

Study setting : operative department , foundation university college of dentistry Islamabad Pakistan.

Sample size : the sample size was calculated using the NCSS PASS software. A total od 180 patients will be tested in the study divided in three groups of 60 patients each. Consent will be taken from pateints on a standardized form approved by the ethics review committe in the operatory where the initial assessment will be done.

Procedure:

1. number of operaters will be restricted two, with similar level of experience in order to minimize operater variation
2. the investigator and co investigator will calibrate each other on the sequence of the procedure and assessment to enhance standardization of procedure
3. local anaesthesia will be given to patients using lidocaine 2% solution available for dental use in 1.8 ml carpule
4. rubber dam will used for isolation and moisture control in the working field.
5. the tooth to be restored will be seperated from the adjacent tooth using wooden wedges.this will allow seperation of teeth.

6. cavity preparation will be done using a high speed handpiece(W&H) with a round bur(prima) (no1/6 or 1/4). After initial penetration through enamel the carious lesion will be excavated using a a carbide bur in a slow speed handpiece.

   after caries removal any unsupported enamel at the gingival floor will be removed using a gingival margin trimmer.

   the cavity shape will be finalized using a pear shaped bur(243).

7. the width of the final cavity will be measured using a perio probe from the buccal or labial cavo surface margin. Only cavities with less than 1/2 the width of the distance or less from the buccal or lingual cusp tip will be included in the study.
8. sectional metal matrix (unimatrix by TDV Brazil,1/4" by 0.0015,1/4" by.002,height and thickness of matrix) will be applied after removing the previously placed wooden wedges. The wedges will be reintroduced after sectional matrix application.
9. the cavity will be etched using 37% phosphoric acid etchant(30 seconds enamel and 15 seconds dentine) followed by rinsing for 30 seconds with the triple syringe. the cavity will be gently air dried while keep a dried cotton pellet in the cavity to absorb excess moisure for 30 to 45 seconds.Prime and Bond NT (Dentsply) adhesive will be applied to the cavity followed by curing for 20 seconds with an led based curing light (O-light,DTE wavelength of 400nm visible blue light). The cavities in all intervention arms will be restored with neo spectre NT composite(dentsply). (the detail of each intervention arm is given under their respective headings)
10. after the cavities are filled the matrix band and the wedges will be removed.the cavity will be finished using diamond burs and composite finishing spirals(azdent). occlusal adjustment will be done where needed using articulating paper.
11. the final restoration will be polished using diamond polishing paste(ultradent) and goat hair brushes (ultradent)

Assessment

1. assessment will be done by passing waxed dental floss between the filling and adjacent tooth by a single independent assessor blinded to the treatment allocation.
2. outcome will be assessed using the contact tightness and contour component of the modified USPHS rating scale
3. data collection will be done at the end of the treatment using a printed porforma for recording the study variables.

Data analysis

1. will be done using spss 26

2. for continouse variables like age and cavity wifth and depth , mean and standard deviations will be computed.

   comparison of these variable will be done by one way anova test

3. for categorical variables like gender, type of tooth,location of cavity,contact tightness and contour(outcome variables) frequencies in percentages will be reported. these variables will be compared using kruskal-wallis test at 0.05 level of significance