The goal of this study is to learn about the temperature rise inside the living part of a tooth (the pulp) during different ways of removing a small amount of enamel (the hard outer layer of the tooth), a procedure called Interproximal Enamel Reduction (IPR).

The goal of this study is to learn about the temperature rise inside the living part of a tooth (the pulp) during different ways of removing a small amount of enamel (the hard outer layer of the tooth), a procedure called Interproximal Enamel Reduction (IPR).

The main question it aims to answer is:

Which IPR technique causes the highest temperature rise in the live tooth pulp?

This study is important because, until now, no research has measured these temperature changes in the live pulp of teeth inside a person's mouth (in vivo) that includes both premolars and front teeth (incisors). The original studies only used premolars, and the results might be different for front teeth due to the difference in enamel thickness.

Researchers will use 20 premolar teeth and 20 incisors that will be scheduled for extraction as part of orthodontic treatment. The teeth will be divided into two groups based on the IPR method used:

Group 1: IPR using a high-speed air-driven drill (airotor) and bur. Group 2: IPR using an orthodontic IPR kit (an oscillating system).

Participants will:

Receive local anesthesia to numb the tooth. Have the baseline temperature of the pulp recorded using temperature sensor on either side of the teeth.

Have the temperature changes in the pulp recorded using temperature sensor while IPR is performed on the sides of the tooth.

Have the tooth extracted afterward (as part of original orthodontic plan)

The key findings may provide information of the IPR method that cause a temperature rise high enough to harm the pulp. A rise beyond 5.5∘C may cause pulp damage.

Study Objectives The primary goal of this investigation is to evaluate the in vivo (inside the body) temperature rise within the dental pulp (the living tissue inside the tooth) when different techniques of Interproximal Enamel Reduction (IPR) are performed.

The core aims are:

1. To measure and compare the magnitude of pulp temperature increase across two common IPR methods.
2. To determine if any of the evaluated techniques have the potential to raise the pulp temperature above a critical threshold (5.5 degrees C), which is historically associated with irreversible pulp damage.
3. To identify which IPR technique carries the highest possibility of thermal injury.

Rationale and Significance Previous studies that looked at this issue were performed ex vivo (on extracted, non-living teeth). This study is crucial because it measures temperature changes in live, intact teeth under actual clinical conditions, providing a more reliable assessment of risk.

A key difference in this research, compared to other literature, is the inclusion of both incisors (front teeth) and premolars. Since the enamel thickness on incisors is generally less than on premolars, there is a possibility that the heat generated during IPR may transfer more readily to the pulp in the anterior teeth, potentially leading to a greater temperature rise and a higher risk of adverse thermal effects. This study aims to clarify this potential risk.

Study Design and Methods This is a randomized clinical trial, an in vivo study involving participants undergoing orthodontic treatment where tooth extraction is required.

Participant Population The study will involve participants for whom the extraction of specific teeth (premolars and incisors) has been clinically advised as part of their orthodontic treatment plan. These teeth will be used for the IPR procedures just before they are extracted.

Procedure Groups (Interventions)

The teeth will be randomly assigned to one of the following two IPR technique groups, with the potential for each to generate a different amount of frictional heat:

1. High-Speed Air-Driven Drill (Airotor and Bur): This method involves high rotational speed (potentially over 300,000 RPM) and thus has the highest possibility of causing the greatest temperature elevation due to intense friction.
2. Orthodontic IPR Kit (Oscillating System): This technique operates at a much lower speed (around 5,000 RPM) and is expected to result in a moderate temperature increase, presenting a moderate possibility of thermal effect compared to the high-speed drill.

Measurement Prior to the IPR procedure, local anesthesia will be administered. A sensitive thermocouple directly on the surface of tooth to meausre baseline temperature of the pulp.

The chosen IPR procedure will be performed. The temperature changes in the pulp will be monitored at two time points and recorded during the IPR process.

The data gathered will be used to compare the techniques and determine the relative possibility of thermal damage posed by each method, particularly within the incisors, which are uniquely included in this research.

Inclusion Criteria:

• Participants 12 to 25 years of age.
• Participants undergoing orthodontic treatment requiring extraction of the teeth being studied (Incisors or Premolars).
• Selected tooth must be intact (no decay, large fillings, or fractures).
• Tooth must test vital (alive and healthy) prior to the procedure.
• Tooth must have healthy surrounding gum tissue.

Exclusion Criteria:

• Teeth that are non-vital (dead), have root canal treatment, or signs of irreversible pulpitis.
• Teeth with existing large or deep restorations (fillings) or crowns/veneers.
• Teeth that have undergone any previous IPR or stripping procedure.
• Teeth with significant developmental enamel defects (e.g., severe hypoplasia or fluorosis).
• Participants with severe systemic diseases (e.g., uncontrolled diabetes) affecting dental health.
• Participants taking medications that affect pulp sensation or vascular response (e.g., long-term anti-inflammatories).
• Participants who are pregnant or breastfeeding.

Conditions for Sharing:

Request Process: Requests must be made formally to the Principal Investigator (or corresponding author) of the study.

Purpose: Requests must include a detailed research proposal outlining the scientific rationale for using the data.

Anonymization: All shared data will be fully anonymized to protect participant confidentiality and meet the requirements set forth by the institutional ethics review board.

Timing: Data will be made available following the publication of the main study results.

Data Use Agreement: Researchers accessing the data will be required to sign a formal data use agreement to ensure the data is used only for the approved purpose and is not shared further.