Permanent Tooth Agenesis and Associated Dental Anomalies among Orthodontically Treated Children

(1) Background: Tooth agenesis is one of the most common developmental dental anomalies often affecting the maxillary incisors area and premolar regions. (2) Purpose: The aim of this study was to assess the prevalence and distribution of permanent tooth agenesis and the associated dental abnormalities among orthodontically treated children. (3) Materials and Methods: This study was carried out utilizing 3000 pretreatment records of children who underwent orthodontic treatment, 1780 (59%) females and 1220 (41%) males, aged 10-25 years (mean age 15 years). Tooth agenesis and other dental anomalies were surveyed using their panoramic radiographs, according to gender, pattern, and location. The level of statistical significance was set at p < 0.05 using t-test or Chi-Square tests. (4) Results: The total number of missing teeth, excluding third molars, was 518 (17%) found in 326 (11%) children. The majority were the maxillary lateral incisors, which was 176 teeth (34%) (p < 0.05). Of them, 111 (63%) were in females, and 65 (37%) were in males. The second most common missing tooth was mandibular second premolars, which was 137 teeth (26%), followed by missing 73 (14%) maxillary second premolars. Impacted teeth had the highest associated dental anomaly prevalence (14.3%), while transposition showed the lowest anomaly prevalence (0.5%). (5) Conclusions: A prevalence of 11% for tooth agenesis was detected in this study. More teeth were missing in the maxilla compare with the mandible. A significant association was found between missing maxillary lateral incisors and missing premolars (p < 0.05). Associated dental anomalies included an increased number of peg-shaped maxillary lateral incisors, palatally displaced and impacted maxillary canines, ectopic teeth, and infra-occluded (submerged) primary second molars.

Agenesis of Permanent Canines in Orthodontic Patients: Prevalence, Location, Treatment Options and Outcomes

Purpose: Tooth agenesis is one of the most common anomalies of the human dentition, found most often in the maxillary anterior region and in the mandibular and maxillary premolar regions. Little information is available on the prevalence and distribution of permanent canine agenesis. The purpose of this retrospective study was to evaluate the prevalence and distribution of permanent canine agenesis in orthodontic patients and describe treatment options and outcomes. Methods: The records of 3,000 consecutively treated patients in the Department of Orthodontics, Tel Aviv University, Tel Aviv, Israel were reviewed. The pre-treatment facial and intraoral clinical photographs as well as panoramic and periapical radiographs were used to detect permanent canine agenesis in both dental arches. The data were recorded according to sex, age, number of missing canines, and their location. Results: Twenty-three patients (0.76 percent), nine males (39 percent) and 14 females (61 percent) had 38 congenitally missing canines. Of these, 22 (58 percent) were missing in the maxilla and 16 (42 percent) were missing in the mandible. Conclusions: The overall prevalence of missing permanent canines in our population was 0.76 percent. The female-to-male prevalence ratio was approximately three to two and more canines were missing in the maxilla than in the mandible.

Three cases of renal relapse after allogeneic hematopoietic stem cell transplantation for childhood acute lymphoblastic leukemia

Isolated renal relapse after allogeneic hematopoietic stem cell transplantation (alloHSCT) in children with acute lymphoblastic leukemia (ALL) is a rare condition. Generally, in ALL, the sites most frequently affected by extramedullary relapse are the central nervous system (CNS) and the testicles. Here we report on three young boys with relapsed B-precursor ALL, who underwent alloHSCT from HLA-identical siblings and suffered a histopathologically proven isolated unilateral renal relapse (two patients) or a combined renal and testicular relapse (one patient) 6, 10 and 12 months post alloHSCT. In all patients at the time of relapse bone marrow showed complete remission with complete donor hematopoiesis. They all received total body irradiation with partial shielding of the kidneys as part of their conditioning therapy, such that renal shielding could be an explanation for the observed accumulation of renal relapses. Moreover, during the past few years so called immune privilege has been postulated for frequent relapse sites such as the CNS, the testicles and the anterior chamber of the eye. Impaired accessability of these organs by cytotoxic T-cells (CTLs) with a reduced graft-versus-leukemia (GvL) effect after alloHSCT is based on a number of different molecular and cellular mechanisms. Similar mechanisms have been shown to be effective in the tubulointerstitial space of the kidney, rendering the kidney a potentially immune privileged site. Due to these observations we advocate sufficient treatment of the kidneys during conditioning therapy.