Orthodontic treatment is more complicated when both soft and hard tissues must be considered because an impacted maxillary canine has important effects on function and esthetics. Compared with extraction of impacted maxillary canines, exposure followed by orthodontic traction can improve esthetics and better protect the patient's teeth and alveolar bone. Therefore, in order to achieve desirable tooth movement with minimal unexpected complications, a precise diagnosis is indispensable to establish an effective and efficient force system. In this report, we describe the case of a 31-year-old patient who had a labio-palatal horizontally impacted maxillary left canine with a severe occlusal alveolar bone defect and a missing maxillary left first premolar. Herein, with the aid of three-dimensional imaging, sequential traction was performed with a three-directional force device that finally achieved acceptable occlusion by bringing the horizontally impacted maxillary left canine into alignment. The maxillary left canine had normal gingival contours and was surrounded by a substantial amount of regenerated alveolar bone. The 1-year follow-up stability assessment demonstrated that the esthetic and functional outcomes were successful.

AIM:To compare the efficacy and safety of early combination therapy with ranibizumab and dexamethasone intravitreal implants versus ranibizumab monotherapy for the treatment of macular edema secondary to retinal vein occlusion(RVO-ME).METHODS: A retrospective cohort study was conducted on a total of 62 cases(64 eyes)of patients who were first diagnosed with RVO-ME at the Eye Centre of the Affiliated Hospital of Shandong Second Medical University between February 2022 and February 2023. The subjects were divided into two groups according to the different treatment regimens: 32 cases(34 eyes)in the monotherapy group received only ranibizumab [3+pro re nata(PRN)regimen], and 30 cases(30 eyes)in the combination therapy group were injected with ranibizumab once first, followed by dexamethasone intravitreal implant 3 wk later(1+DEX regimen). The best corrected visual acuity(BCVA), central retina thickness(CRT), foveal avascular zone(FAZ)area, macular vascular density(MVD)at the level of the deep vascular complex(DVC)of the retina, the incidence of ocular adverse effects, the number of drug injections, and the total cost between the two groups were compared before and after treatment.RESULTS: At 3 wk, 3 and 6 mo, and at the final follow-up of the two groups of patients, the improvement in BCVA, CRT, and MVD in the DVC layer was significantly better than that before treatment(all P<0.05); there were differences in the comparisons of BCVA and CRT between the two groups at 6 mo and the final follow-up(all P<0.05), and the increase in the number of letters of BCVA was the most pronounced in the combination therapy group at 6 mo of treatment. Statistical significant difference was observed in the comparison of MVD in the DVC layer between the two groups at 3 and 6 mo after treatment and at the final follow-up(all P<0.05). However, no significant change in FAZ area was evident before and after treatment in both groups(P>0.05). The combination therapy group exhibited a reduced number of injections and total cost in comparison to the monotherapy group. The combination therapy group exhibited a slightly higher incidence of high intraocular pressure and cataract progression compared to the monotherapy group, with no statistical significant difference(all P>0.05). Furthermore, no serious adverse events were observed in either group following treatment.CONCLUSION:Compared with ranibizumab alone, ranibizumab combined with dexamethasone intravitreal implant significantly improved vision, reduced macular edema, and lowered the frequency of injections and total treatment cost in patients with RVO-ME. CRT and MVD in the DVC layer are reliable prognostic indicators for patients with RVO-ME.