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 Ameloblastoma is an odontogenic tumor with diverse clinical behavior and histomorphologic presentations. Basal cell ameloblastoma are extremely rare variants of ameloblastoma. Keratocystic odontogenic tumor (KCOT) is a distinct form of odontogenic cyst that is considered a benign cystic neoplasm and not a cyst. Co-occurrence of these odontogenic tumors has been rarely reported.This paper reports a 34-year old female patient with a unilocular radiolucency around the crown of a partially erupted third molar that was detected accidentally on a routine radiographic examination. She underwent excisional biopsy with a clinical diagnosis of dentigerous cyst. Histopathologic examination revealed a cystic lesion with criteria of OKC and islands and nests reminiscent of basal cell ameloblastoma and acanthomatous ameloblastoma in the stroma. Follow-up showed no recurrence of lesion to date. Due to the rarity of the lesion, the diagnosis was challenging but altogether we made a diagnosis of keratoameloblastoma with basaloid features.

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Background and purpose: In orthodontic brackets, unlike restorative materials or porcelain, the shear bond strength of the adhesives used is important because the oblique forces from food or objects or the tension of the adhesive food affect the brackets. This study aimed at measuring and comparing shear bond strength and adhesive remnant index of light cure composite, no mix (self-cure) composite, and no bond composite (GC Orthoconnect).
Materials and methods: A total of 27 non-carious and sound human premolar teeth were used. The samples were divided into three groups, including light cure composite, self-cure composite, and no bond composite (GC Orthoconnect). After bonding and thermocycling process, the metal brackets (American Orthodontics) were then debonded using universal testing machine. Adhesive remnant index (ARI) score was assessed.
Results: The highest and lowest SBS mean values were seen in self-cure group (18.0402±5.71665) and light cure group (7.7890±3.98995), respectively. There were significant differences in SBS values between all groups except between the no bond group and the self-cure group (P= 0.18, P>0.05). The highest ARI scores were 0 in the self-cure group and 3 in the no bond group and the light cure group.
Conclusion: The no bond composite provided acceptable overall shear bond strength and compared to light cure composite showed higher shear bond strength and lower bond failure.
 

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Background and purpose: Transverse problems in the maxilla (high arched- narrow hard plates) can cause respiratory disorders. Palatal expansion can be helpful in this way. The present study aimed at evaluating the effect of bone borne expansion and tooth borne palatal expansion on airway volume.
Materials and methods: A review study was performed by search in Google Scholar, Scopus, PubMed, Embase, and Cochrane using the following keywords: maxillary expansion, palatal expansion, miniscrew-assisted palatal expansion, tooth borne, bone borne, rapid palatal expansion, airway dimension, and Cone beam computed tomography. The search was limited to articles published in January 2011-April 2021.
Results: In the initial search, 343 articles were found. After reviewing the titles and abstracts only 20 papers were found that studied the effect of bone and tooth borne palatal expansion on airway dimensions and met the inclusion criteria. The studies indicated that both bone expansion and tooth borne palatal expansion could considerably increase airway volumes. However, only bone borne palatal expansion enabled more predictable and greater skeletal expansion and less teeth response.
Conclusion: Both bone and tooth borne palatal expansion are efficient in increasing the airway volume. Further randomized clinical trials with large sample size and matched control groups, longer follow-up periods and measuring respiration index such as apnea-hypopnea index are suggested.

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 Background and purpose: Skeletal anchorage is a new aid for the correction of moderate anterior open bite. This study aimed at treating moderate anterior open bite using posterior intrusion via mini implants. In addition, a review of studies carried out on open bite correction using absolute anchorage was performed.
Materials and methods: The following keywords were used: open bite, camouflage, extraction, surgery, bone-anchor intrusion, posterior intrusion, mini screw, mini plate, and absolute anchorage. A review of articles was performed in PubMed, Embase, Google Scholar, and Cochrane. The time span of article search was from January 2011 to April 2021. In the case presented in this study, an anterior open bite was corrected with mini implants.
Results: Twelve studies were selected from 42 articles that met the initial eligibility criteria.  In most studies, the reduction in mandibular plane angle (SN-GoGn and FMA) was less than 2^◦ following counterclockwise rotation. But, in some studies the changes ranged between 2.3 and 3.9^◦. In all studies following mandibular autorotation, facial convexity decreased, chin contour improved, and lower anterior face height decreased. Our patient also showed a decrease of 2° in the mandibular plane angle and a decrease of 1°in facial convexity.
Conclusion: According to this study, intrusion of posterior teeth with the aid of moderate skeletal anchorage is a non-invasive camouflage treatment. Also, in the patient studied here it corrected overbite, improved facial appearance, and reduced the need for surgery.