The goal of this clinical trial is to check the effects of lip bumper appliance contribution to driftodontics after designated tooth extractions that are already part of orthodontic treatment plan. The main questions it aims to answer are:

• Is there a significant difference in rate of incisor alignment in lip bumper group?
• Does the lip bumper have any adverse effects on oral hygiene? Researchers will compare the effects of appliance vs no appliance.

Participants will have:

• Appliance cemented in mouth after extractions in interventional group and no appliance in control group
• Three monthly follow up for checkup and impressions

A randomized clinical trial will be conducted, after seeking approval from the Ethical Review Committee of the institution. Patients will be included in the study after taking their consent through an informed consent form, records and finalization of their treatment plans for orthodontic treatment based on inclusion and exclusion criteria. Participants under 18 years of age will consent verbally while their parents or guardian will sign the consent form. A clause for consent of participants under 18 years of age has been included in the informed consent form both in English and Urdu versions. The inclusion of a control group with the same extraction pattern as in lip bumper group will minimize the confounding effect of driftodontics in lip bumper group. Random allocation of patients in lip bumper and control group will be done by distribution of sealed envelope to participants in orthodontic OPD, the sequence of which is generated by clinical trial randomization tool. The envelope will contain either of the two titles as ''lip bumper group'' or ''control group''. The participant will be asked to choose one envelop without prior knowledge of the title inside. The choice of selection of envelope is entirely at participant's discretion, thus ensuring a randomized selection process. This approach guarantees that the participant's choices are independent and free from any selection bias.

Bands will be placed for lower first molars, this will be followed by impression taking of the lower arch for fabrication of lip bumper for the experimental group, while in the control group the bands will be cemented with glass ionomer cement. The lip bumper will be fabricated from 0.045 inch stainless steel round wire covered with a layer of acrylic. The acrylic will extend from canine to canine. The lip bumper will be located between the lower lip and lower anterior teeth with a 2 mm of distance between them and arm inserted into the tube of molar band on the lower 1st molar. It will be set 4-5 mm away from the buccal segments. The top of the shield will be positioned two-thirds from the incisal edge of mandibular incisors. The specifications will be made parallel to the specifications used by Davidovitch et al. Impressions will be taken at the start of treatment T0 and at 1 month intervals T1, T2, T3 for model analysis. Lower incisor crowding will be measured by Little's irregularity index while the gingival health will be recorded as gingival index, plaque index and bleeding on probing and scored as per the criteria mentioned below. For the experimental group one side extraction will be done a week before and the other side on the day of lip bumper insertion. The control group will get their extractions only, both groups will be recalled monthly for impression taking of lower arch, bonding of lower arch will be done after 3 months in both groups, once the data collection is complete. Oral hygiene instructions will be given to both control and experimental group and it will be reinforced on each monthly visit. A single calibrated examiner, the principal investigator, will be placing the bands, lip bumper, giving OH instructions as well as taking all the readings clinically as well as on the models.

Inclusion Criteria:

• A treatment plan involving bilateral extractions of maxillary and mandibular first premolars
• Patients with class 1 and upto quarter cusp class 2 molar relationship
• Moderate to severe incisor irregularity of 4-9 mm as assessed by little's irregularity index
• Presence of all first molars

Exclusion Criteria:

• Developmental, medical or genetic problems
• Patients using bisphosponates
• Spacing in dentition
• Carious lesion in lower first molars which cannot be restored
• Patient with active periodontal disease
• Previous orthodontic treatment