ObjectivesTo determine the optimal sites of mini‐implant placement in the palatal alveolar cortical bone by using cone beam computed tomography (CBCT).Subjects and MethodsCone beam computed tomography records of 60 patients were divided into two groups of equal sizes, based on age and sex. The images were analysed using Planmeca Romexis Software (Version 4.1.2). The measurements were made in axial sections of the maxilla and mandible, at 2, 4 and 6 mm from the CEJ. The optimal sites were defined in terms of (a) Palatal or lingual alveolar cortical bone thickness and (b) Mesiodistal palatal or lingual inter‐radicular width.ResultsThe optimal site for mini‐implant insertion, anteriorly, was the canine‐lateral incisor embrasure in both the jaws. Posteriorly, the inter‐molar embrasure in the mandible and the molar‐premolar embrasure in the maxilla were optimal sites. Females demonstrated significantly lesser bone widths in all areas of the maxilla (P < .05) but greater bone thickness in the mandibular regions, as compared to males. The adolescent age group demonstrated a significantly lesser bone thickness but greater mesiodistal widths than the adult population in both the jaws (P < .05).ConclusionThe optimal sites for mini‐implant insertion were the anterior canine‐lateral incisor and posterior buccal inter‐radicular embrasures, in both the jaws. Significant differences existed between age and gender groups, which need to be kept in mind while choosing the locations for placing mini‐implants.

No abstract

BACKGROUND  To compare and correlate the maxillary sinus dimensions and basal bone height among various facial patterns using CBCT for advanced diagnosis and treatment planning in Orthodontics. METHODS 66 CBCT images within age group of 18-30 years were divided into horizontal (Group 1), average (Group 2) and vertical (Group 3) facial growth patterns. Maxillary sinus dimensions were compared and correlated in all three groups. The sinus height and basal bone height were recorded at 3 locations-between 1st premolar and 2nd premolar (PM1-PM2), between 2nd premolar and 1st Molar (PM2-M1) and between 1st and 2nd molar (M1-M2). RESULTS Overall reduction in sinus height and significantly reduced sinus volume was seen in Group-1. Longest maxillary sinus height in M1-M2 region and shortest in PM1-PM2 region was seen in Group-3. The basal bone height in PM1-PM2 region was significantly longer in Group-3 than in Group-1(p<.05).Shortest basal bone height in M1-M2 region was seen in Group-3. A significant negative correlation was seen between the maxillary sinus height and the basal bone height in Group-1 and Group-3(p<.05). CONCLUSION There is a correlation between the maxillary sinus height and basal bone height with that of facial pattern which needs to be considered during orthodontic treatment planning and while carrying out facial growth modification procedures in younger patients.

Aim: The study aimed to evaluate the shear bond strength (SBS) of metal brackets and adhesive properties of bonded irradiated and non-irradiated teeth. Methods: Sixty-six extracted premolar samples were randomly divided into three groups—(a) Control group consisting of 22 non-irradiated, non-aged teeth (Group 1), (b) 22 non-irradiated, aged samples (Group 2) and (c) 22 irradiated, aged samples (Group 3). Irradiation was done using gamma irradiation with a fractionated dose of 60 Gy for 5 consecutive days per week over 6 weeks. Metal brackets were bonded on all samples with light cure adhesive and subjected to SBS test using universal testing machine. The samples were assessed under the scanning electron microscope to check for the adhesive remnant index (ARI) and tag depth. Results: There was a statistically significant decrease in the mean SBS of the irradiated samples compared to the non-irradiated teeth. The non-irradiated, aged samples showed a majority of ARI scoring 1 and 2. Whereas, the irradiated samples showed ARI scoring 2 and 3. Approximately, 77·3% of the non-irradiated samples showed no adhesive present on the tooth surface, and 27·2% of the irradiated samples had more than 50% adhesive present on the enamel surface. Conclusion: There is a statistically significant decrease in SBS of irradiated enamel compared to that of non-irradiated teeth. However, the SBS observed in the three groups was well above the ideal SBS for orthodontic bonding, that is, 5·6–6·8 MPa. The adhesive remnant was found on all samples of the irradiated group. Deeper adhesive resin tags were found in the irradiated group in the resin–enamel interface.

A BSTRACT Aim: The aim of this study was to assess the changes in maxillary and mandibular third molar inclinations in individuals with class II div 1 malocclusion, before and after orthodontic treatment with extraction of all four first premolars. Materials and Methods: This retrospective study consisted of the pretreatment and posttreatment records of 30 patients that were obtained from the archives of the department of orthodontics and dentofacial orthopedics in A B Shetty Memorial Institute of Dental Sciences. The maxillary third molar’s relation to the palatal plane and the mandibular third molar’s relation to the mandibular plane were measured. The paired t test was used to calculate pre- and posttreatment changes. A value of P < 0.05 was considered to be statistically significant. Results: The maxillary third molars showed a mean correction of 6.15° ( P < 0.001) and the mandibular third molars showed a mean correction of 5.10° ( P < 0.001). Conclusion: Maxillary third molars showed more uprighting when compared to the mandibular third molars and that both maxillary and mandibular third molars showed an improvement in their angulations to their respective planes after extraction of the first premolars. However, the results of the study cannot be analyzed to state if the third molars do become fully functional.