###### Abstract  
(1) Background: Skeletally anchored appliances for maxillary expansion are a less invasive alternative to surgery and are increasingly often selected as a method of treatment. The purpose of this study was to retrospectively evaluate the efficacy of maxillary expansion using distractors supported by temporary orthodontic implants (TOIs) in patients of differing sex and age. (2) Methods: The study group consisted of patients treated with distractors anchored to TOIs between July 2019 and June 2022. The group was divided into adolescent and the adult patients. Effectiveness was evaluated one and two weeks after installation of the distractors and the results were analyzed statistically. (3) Results: In total, 39 patients were treated, of which 21 were women and 18 men, ranging in age from 11 to 42. A group of 8 girls and 9 boys younger than 18 years were included. The presence of diastema at the first follow-up visit was observed in all girls and in 8 of the boys, as well as in 7 women and in none of the men. At the second visit, no diastema was found in one woman, but was noted in 3 men (\(p\) = 0.007). At the completion of distraction, diastema was observed in all the girls and in 12 women, as well as in 8 out of 9 boys and in 3 men (\(p\) = 0.015). (4) Conclusions: The effectiveness of the distraction procedure in adolescents is positive, regardless of sex. However, in adults, the procedure has limited effectiveness in males.  
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membrane (e.g., Haas-type expanders); these are especially effective in children prior to the peak of skeletal growth, when the palatal suture is not very sinuous [4; 8]. These methods can result in side-effects such as dentoalveolar tipping, root resorption, and gingival recession [9], generally among patients closer to eighteen years of age [2; 10; 11]. In patients over eighteen, treatment with these devices is ineffective and can have more serious side effects. To avoid these and to allow expansion, temporary implants have begun to be used as bone-borne anchorages. This method allows palatal expansion in patients over eighteen and helps to avoid surgically assisted palatal expansion (SARPE), which is an alternative method of treatment that requires general anesthesia; the healing process after this procedure is definitely longer and associated with more discomfort. Similarly, the removal of the distractor sometimes requires general anesthesia and is carried out in a hospital setting [2; 12; 13; 14].  
Skeletally anchored appliances for rapid maxillary expansion are a less invasive alternative to surgery. Their use is associated with surgery under local anesthesia and is performed in an outpatient setting in the dentist's office. This approach is used increasingly often as a means of expanding the maxillary dental arch when its narrowing has resulted in unilateral or bilateral crossbite. One advantage of this treatment method, the prevention of sleep apnea, is often highlighted [5; 15; 16]. However, the effectiveness is not always predictable: greater predictability and certainty of success is found in younger patients, as confirmed by numerous papers [15; 17; 18]. For example, maxillary expanders (especially hybrid Hyrax appliances) prevents mesialization of the molars until the premolars erupt [19]. Research has pointed to inconsistent results for treatment success, especially among adults [20; 21]. However, no one has unequivocally noted differences in the success of maxillary distraction in male and female patients. For this reason, we decided to investigate further.  
The purpose of this study was to retrospectively evaluate the efficacy of the maxillary expansion procedure using distractors supported by temporary orthodontic implants, in patients of different sex and ages.