The success rate of mini-screws for incisors intrusion and patient age, gender, and insertion angle in the maxilla using CBCT and implant-guided surgery. A split-mouth, randomized control trail.

BACKGROUND AND OBJECTIVES: The intrusion of anterior teeth is a routine procedure in orthodontics, which has been performed efficiently with the help of mini-screws in the anterior region, especially the upper maxilla. This study aimed to investigate the effect of insertion angle and sociodemographic features on the success rate of mini-screws at the anterior maxillary region. MATERIALS AND METHODS: Twenty-nine patients (18 Females and 11 Males) aged 18-40 years old were involved in the current study. A split-mouth design was carried out in which recruited patients needed bilateral anterior screws at the labial bone in the region of the incisor for the intrusion of upper anterior incisor teeth as part of their orthodontic treatment with a fixed appliance (upper right side received 90-degree insertion angle mini-screw and 45° for left side) using a surgical guide fabricated from patients CBCT and intraoral scans. The mini-screws were inserted at the attached gingiva bilaterally to achieve intrusion of upper anterior teeth with a power chain ligated from the main archwire to the anterior min-implants. The patient was recalled monthly for orthodontic appliance activation and screw assessment for 6 months. The intrusion force was 15 g on each side. RESULTS: The results of the study showed that screw stability was higher in the male group than the female group at the 6th monthly follow-up visit with a statistically significant difference between both genders (P = .044). Concerning insertion angle, results showed a statistically significant difference between 45° and 90° as an insertion angle with a P-value <.01 in most of the follow-up months. CONCLUSION: This study found that male patients with mini-screws inserted at 90° showed greater screw stability over time.

Evaluation of the enamel nano-topography influenced by different techniques of interproximal reduction: An atomic force microscopic study.

INTRODUCTION: Interproximal enamel reduction is a part of the orthodontic treatment as a method of space generation in addition to other vast indications. Some studies found that different techniques might impose changes to the enamel surface that alter its topography, which in turn might influence its integrity and susceptibility to caries. Polishing, however, after this procedure is thought to be helpful to reduce these adverse effects. AIM: To evaluate the nano-topography of the enamel surfaces after interproximal reduction (IPR) and determine its influence on enamel surface roughness and examine the need for polishing to minimise these influences, when combined with topical fluoride application. METHODS: A total of 60 proximal surfaces of 40 extracted maxillary premolars (10 premolars left unprepared as the control group) were reduced with different stripping instruments (discs, burs and manual strip system). The surface roughness of enamel was analysed with an atomic force microscope to determine the results quantitatively as well as qualitatively on the nanoscopic scale. One of each proximal surface was followed by polishing and fluoride varnish after the reduction. RESULTS: The results showed that surface roughness was increased in all groups without polishing. The greatest mean roughness was recorded for the disc group (212 ±125.7), followed by the bur group (172 ±93.1) and manual strips (153.8±106.7). The difference between the groups, however, was not significant for both mean roughness (P = 0.656) and height (P = 0.737). The parameters were decreased after polishing in all groups but the difference between methods was not significant for both parameters (P = 0.946 and P = 0.849); however, the mean height was reduced to nearly half the reading in the bur and manual strip method. The disc group only showed a statistically significant decrease in surface roughness with polishing (P < 0.05). All other results were not significant. CONCLUSION: All methods of interproximal reduction do not influence enamel surface nanotopography significantly with and without polishing. Polishing resulted in significant reduction of surface roughness only in the disc group.

The Effect of Submucosal Injection of Plasma-Rich Platelets on Blood Inflammatory Markers for Patients with Bimaxillary Protrusion Undergoing Orthodontic Treatment.

OBJECTIVES: The present study aims to reveal the systemic effects of submucosal injection of plasma-rich platelets (PRP) on blood inflammatory markers which was used in an attempt to reduce the retraction time of the upper canine following extraction of upper maxillary premolars for patients with bimaxillary protrusion. HYPOTHESIS: No change on comparing the values of blood inflammatory markers before and after submucosal injection of PRP. METHODS: Eighteen female patients with bimaxillary protusion were selected from patients seeking orthodontic treatment from the College of Dentistry/University of Sulaimai, whose maxillary and mandibular first premolars were decided to be extracted after proper diagnosis. Thirty-three blood markers (twenty hematological and thirteen biochemical markers) were estimated before orthodontic bracketing, 24 hours and 7 days following submucosal injection of PRP (5 cc) to reveal the systematic effect of PRP on blood inflammatory markers that were used in an attempt to reduce the retraction time of the upper canine following extraction of upper maxillary premolars for patients with bimaxillary protrusion. RESULTS: The results indicate nonsignificant differences in the values of all blood markers except for gamma GT (GGT), PDWa, serum albumin, serum total protein, and total calcium. Gamma level significantly increased for both test intervals. On the other hand, there was a significant drop in the value of PDWa while for alkaline phosphatase, there was a drop within the first 24 hr of PRP injection while after 7 days the value was significantly increased. On the other hand, there was a drop in the level of serum albumin, while there was an increase in the serum total protein and total calcium. CONCLUSION: Submucosal injection of PRP could lead to systematic alteration of blood parameters including ALK phosphatase, gamma GT, serum albumin, and serum total protein, which may be related to liver function in addition to increase in the level of PDWa and serum calcium. We present evidence that PRP contains and may trigger systemic effect. Thus, further investigation is recommended to follow up the patient for a longer period of time and on a larger sample. This trial is registered with U1111-1221-8829 by Sri Lanka Clinical Trial Registry, SLCTR/2018/040, and No. 64 on 6th August 2018 at the local clinical studies database, College of Dentistry.