Microbiological Evaluation of Single Versus Multiple Visits Regeneration Using MALDI-TOF Mass Spectrometry

Study Overview
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Brief Summary
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Aim of the study is to assess canal disinfection using matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) in single visit and multiple visit regeneration protocols, and to assess clinical and radiographic outcomes of single visit and multiple visit regeneration protocols.

Detailed Description
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Thirty patients with necrotic immature permanent teeth showing periapical lesions will be randomly divided in two groups: group (1) single visit regeneration and group (2) multiple visits regeneration protocol, in which calcium hydroxide will be applied for one week or more according to resolution of signs and symptoms. Dentin debris collected on a file will be taken as microbiologic sample to be cultured and examined by MALDI-TOF MS. This will be performed after the access cavity preparation and after irrigation in both groups, these samples will be labelled A and B, respectively. In group (2) there will be a third sample labeled C which will be taken after the removal of the intra canal calcium hydroxide.

Official Title
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Microbiological Evaluation of Single Versus Multiple Visits Regeneration Using MALDI-TOF Mass Spectrometry (A Randomized Controlled Clinical Trial)

Conditions
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Pulp Necroses, Tooth, Nonvital

Intervention / Treatment
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* Biological: Single-visit regeneration protocol
* Biological: Multiple-visits regeneration protocol


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Immature permanent upper anterior teeth. Necrotic teeth confirmed by sensibility test. Teeth with periapical lesions confirmed by periapical radiograph using paralleling device. Exclusion Criteria: Teeth with orthodontic wires or brackets. Patient with history of allergy to any medication. Patient with history of bleeding disorders. Patient with medical illness or taking medications.

Ages Eligible for Study
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Minimum Age: 8 Years
Maximum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Single-visit regeneration protocol<br> | Biological: Single-visit regeneration protocol<br>* In a single visit, access opening, minimal instrumentation and irrigation will be done. After irrigation and drying, the apical tissue will be irritated to evoke bleeding in the canal, using a precurved K-file 2mm past the apical foramen, with the goal of having the entire canal filled with blood to the level of the cemento-enamel junction. The bleeding will be stopped at a level that allows for 3-4 mm of restorative material. Three millimeters of Biodentine will then be placed directly over the blood clot of each tooth. A 3-4 mm layer of glass ionomer is flowed gently over the capping material. Each access cavity will be restored using composite resin.<br>|
| Active Comparator: Multiple-visits regeneration protocol<br> | Biological: Multiple-visits regeneration protocol<br>* In the first visit, access opening, minimal instrumentation and irrigation will be done. The root canal will be then dried and filled with calcium hydroxide paste. The tooth will be sealed with an intermediate restorative material (IRM), and the patient will be dismissed for 1-4weeks. In the second appointment, response to initial treatment will be assessed and the steps will be repeated if symptoms are persistent. If there are no symptoms, evoking bleeding to the level of the cemento-enamel junction will be done followed by Biodentine application over the blood clot with final glass ionomer and composite restorations.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Microbiological assessment | The presence or absence of reduction in types of micro-organisms in root canals | 24 hours | 
| Tooth vitality | Tooth vitality will be assessed by sensibility testing using thermal stimulation, binary (yes or no). | up to 12 months | 
| Tooth mobility | 4. Mobility will be recorded according to Grace & Smales Mobility Index Grade 0: No apparent mobility Grade 1: Perceptible mobility <1mm in buccolingual direction Grade 2: 1mm< but <2mm Grade 3: 2mm< or depressibility in the socket | up to 12 months | 
| Healing of periapical lesions | Periapical index score (PAI) will be used for identification of apical periodontitis on both periapical radiography and Cone-beam computed tomographic (CBCT). It is a 6-point (0 -5) scoring system with 2 additional variables, expansion of cortical bone and destruction of cortical bone.The PAI will be determined by the largest extension of the lesion on periapical radiography and CBCT scans in 3 dimensions: axial, sagittal, and coronal. Score 0 Intact periapical bone structures. Score 1 Diameter of periapical radiolucency 0.5-1 mm. Score 2 Diameter of periapical radiolucency 1-2 mm. Score 3 Diameter of periapical radiolucency 2-4 mm. Score 4 Diameter of periapical radiolucency 4-8 mm. Score 5 Diameter of periapical radiolucency 8 mm. Score (n)# E: Expansion of periapical cortical bone. Score (n)# D: Destruction of periapical cortical bone. | up to 12 months | 
| Root lengthening | The root length will be measured as a straight line from the CEJ to the radiographic apex of the tooth. This will be measured on both periapical radiography and Cone-beam computed tomographic (CBCT) in millimeters. | up to 12 months | 
| Root thickening | The dentinal wall thickness for both the preoperative and recall images will be measured at the level of the apical one third of the preoperative root canal length measured from the CEJ. The root canal width and the pulp space will be measured at this level, and the remaining dentin thickness will be calculated by subtracting the pulp space from the root canal width. | up to 12 months |