Evaluating Laser and Piezocision vs. Piezocision Alone on Root Resorption and Gingival Health During Tooth Retraction

Damascus University66 enrolled

Overview

This trial aims to determine whether using a special laser (low-level laser therapy, or LLLT) in combination with a minor surgical procedure (piezocision) can safely accelerate orthodontic treatment. We are looking at its effect on two main safety issues: root shortening (root resorption) and gum health. We will compare three groups of patients who have their front teeth pulled back: one group receives the surgery and the laser, one receives the surgery alone, and one receives standard braces. We will measure root length on X-rays and check gums at the start, before the retraction phase, and after all the space is closed.

Class II, Division 1 malocclusion is a common condition often treated by extracting upper premolars and retraction of the front teeth (en-masse retraction). This phase can take 9-12 months, increasing the risk of complications like poor oral hygiene, gum inflammation, and external apical root resorption (EARR). To address this, methods to accelerate tooth movement have been developed, including surgical (piezocision) and non-surgical (LLLT) techniques. While these methods aim to reduce treatment time, their combined effects on safety outcomes, such as EARR and periodontal health, are unclear. This three-arm randomized controlled trial evaluates the effects of en-masse retraction assisted by piezocision combined with LLLT (FC+LLLT), compared to piezocision alone (FC) and conventional treatment (CONT). Sixty-six patients were randomly assigned to the three groups. The piezocision procedure involved 18 minimal incisions and cortical bone perforations using a piezosurgery tip. The FC+LLLT group received adjunctive Ga-Al-As diode laser (808 nm, 1.1 W, 4 J/point) at multiple sessions. En-masse retraction was performed with 250g force using Ni-Ti coil springs from mini-screws. EARR was measured on standardized panoramic radiographs at T0 (pre-treatment), T1 (pre-retraction), and T2 (post-retraction) using a crown-length correction method. Periodontal health (Gingival Index, Papillary Bleeding Index, Dental Plaque Index, and Gingival Recession) was assessed at the same time points. The study aims to determine if these acceleration techniques increase the risk of these iatrogenic complications.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

Interventions

Flapless Corticotomy (Piezocision)PROCEDURE

Performed 4 days before retraction. Eighteen minimal intrasulcular incisions and cortical bone perforations (3mm depth) using a piezosurgery microsaw tip.

Level Laser Therapy (LLLT)PROCEDURE

Ga-Al-As diode laser (808 nm, 1.1 W, 4 J/point, 15 sec/point) applied to 32 points per session. Administered on days 0, 3, 7, 14, and then bi-weekly for a total of four sessions post-initiation, starting six weeks post-corticotomy.

Traditional treatmentPROCEDURE

Patients in this group will be traditionally treated without being subjected to corticotomy or LLLT.

Eligibility

Sex: ALLMin age: 17 YearsMax age: 28 Years

Medical Language ↔ Plain English

Inclusion Criteria: 1. Healthy patients aged 17-28 years. 2. Diagnosed with a Class II division 1 malocclusion, indicated for extraction of the upper first premolars, with an overjet of 4-10 mm and a normal or increased facial height assessed clinically and cephalometrically using three angles (MM= 23ᵒ-33ᵒ, Jarabak Ratio ≤ 64%, and Y-axis angle= 66ᵒ-75ᵒ) 3. A skeletal Class II relationship, confirmed by a cephalometric ANB angle between 4° and 7° 4. An overbite of 0%-33% 5. Good oral hygiene, defined by a probing depth of ≤3 mm and no radiographic evidence of alveolar bone loss 6. Absence or a mild level of crowding 7. A full complement of teeth, excluding third molars. Exclusion Criteria: 1. A history of previous orthodontic treatment 2. Any systemic disease or medication known to interfere with orthodontic tooth movement. 3. Congenitally missing or extracted teeth in the maxilla (except third molars) 4. Poor oral hygiene, 5. Active periodontal disease (probing depth ≥4 mm, radiographic bone loss, gingival index \>1, plaque index \>1) 6. Moderate to severe maxillary crowding (Little's Irregularity Index ≥4).

Outcomes

Primary Outcomes

Change in external apical root resorption

The root length will be measured for each root of six upper anterior teeth. The method originally described by Linge and Linge will be used. The amount of root resorption (in millimeters) will be calculated using the following equation: Root Resorption = Root Length (T0) - (Root Length (T1) × Correction Factor). The Correction Factor will be calculated by dividing the crown Length (T0) to the crown Length (T1).

Time frame: (T1) one day before treatment commencement, (T2) at the end of the levelling stage (expected to occur within 3 - 4 months), (T3) one day after the end of retraction (expected to occur within 6 months).

Change in the Gingival Index

Assessment will be performed using a gingival probe according to the Silness and Loe method: 0\. Normal gingiva. 1. Mild inflammation: slight color change, slight edema. No bleeding on probing. 2. Moderate inflammation: redness, edema, and glazing. Bleeding on probing. 3. Severe inflammation: marked redness and edema, ulceration, and tendency to spontaneous bleeding.

Change in the Dental Plaque Index

Assessment will be performed using a gingival probe according to the Silness and Loe method. 0\. No plaque. 1. A film of plaque adhering to the free gingival margin and adjacent area of the tooth. The plaque may be seen in situ only after a disclosing solution is applied or after the probe is used on the tooth surface. 2. Moderate accumulation of soft deposits within the gingival pocket, or on the tooth and gingival margin, which can be seen with the naked eye. 3. Abundance of soft matter within the gingival pocket and/or the tooth and the gingival margin.

Change in the Bleeding Index

The Bleeding index will be used to assess the status of periodontal tissues and the amount of congestion in the gingival margins around the anterior teeth. According to Muhlemann, an assessment will be performed using a gingival probe. 0. No bleeding. 1. A single discrete bleeding point appears. 2. Several isolated bleeding points or a single fine line of blood appear. 3. The interdental triangle fills with blood shortly after probing. 4. Profuse bleeding occurs after probing; blood flows immediately into the marginal sulcus.

Change in Gingival Width

This will be measured in millimeters from the cement-enamel junction to the gingival margin level around the six anterior teeth

Secondary Outcomes

Change in Pulp Vitality

This will be assessed using a cold test with -50° ethyl chloride spray. The patient's pain response will be recorded to confirm pulp vitality. There are two answers: (1) Yes, or (2) No.