Tooth eruption is a series of complicated physiological processes occurring once the crown is formed completely, as well as when the tooth moves toward the occasion plane. As such, the tooth moves through the alveolar bone and the oral mucosa until it finally reaches its functional position. Most studies indicate that the process of tooth eruption involves the alveolar bone, dental follicles, osteoclasts, osteoblasts, and multiple cytokines. Dental follicles regulate both resorption and formation of the alveolar bone, which is required for tooth eruption. Furthermore, root formation with periodontal ligament facilitates continuous tooth eruption. However, the exact mechanism underlying tooth eruption remains unclear. Hence, this review describes the recent research progress on the cellular and molecular mechanisms of tooth eruption.
Dental Sac ; Humans ; Osteoblasts ; Osteoclasts ; Periodontal Ligament ; Tooth ; Tooth Eruption ; physiology ; Tooth Root

OBJECTIVEThis study  aims  to  assess  the  remineralization effect of casein phosphopeptide (CPP)-amorphous calcium phosphate (ACP) on enamel demineralization by  performing  system review of  randomized  controlled  trials (RCT)  involving  the  treatment of enamel demineralization with  CPP-ACP.

METHODSThe  study  was  developed  based  on  the 
Cochrane handbook  for  systematic  reviews of  interventions (Version 5.1.0) and included  the  following: search  strategy, selection  criteria, data  extraction, and  risk  of  bias  assessment. We  searched electronic  databases  such  as  PubMed, Embase, Cochrane Library, CNKI, Wanfang and VIP up  to  September  2016. RCT of  treating  enamel demineralization with  CPP-ACP were  included. Data  extraction  and  domain-based  risk  of  bias  assessment  were independently  performed  by  two  reviewers.

RESULTSTwelve  RCTs  were  included.  Because of the difference of experimental design and evaluation standards, the quantitative analysis can not be carried out.

CONCLUSIONSThere is no strong evidence that CPP-ACP is superior to conventional fluoride formulations in enamel remineralization. However, due  to the limitations of sample size, follow-up time and study design,  more high quality and large-sample RCT are needed to  further  verify  the evidence.

The properties of adhesives and light-cured resin composites are closely related to the repair of dental defects. Therefore, improving the properties of adhesives and resins composite to increase the success rate of filling has been the focus of research in the field of prosthodontics in recent years. Current studies have confirmed that temperature can change the properties of adhesives and light-cured resin composites, affecting their repair effect. A proper storage temperature ensures the good performance of materials: the self-etching adhesive system should be refrigerated, and the light-cured resin composite should be refrigerated or stored at room temperature according to its composition, proportion and other properties; however, the appropriate storage temperature for the etch-and-rinse adhesive system is not clear. The appropriate application temperature could improve the fluidity, monomer conversion, bonding strength, compressive strength and other properties of the materials to improve the quality of filling restoration. However, there is a wide variety of adhesives and resin composites, and the effect of temperature on each material is different. Thus, it is still necessary to explore the temperature range for material storage, precooling and preheating. Few studies have been performed in vivo, and the clinical restorative effects of adhesives and resin composites stored and used at different temperatures need to be further studied.

OBJECTIVETo investigate the outcome of skeletal Class Ⅲ patients treated with Fränkel function regulator type Ⅲ (FR Ⅲ)in the early mixed and late mixed dentition.

METHODSThe samples consisted of 45 mild and moderate skeletal Class Ⅲ patients(26 males, 19 females; meanage, [7.9±1.3] years) treated with FR Ⅲ. According to Hellman's dental developmental stages, these samples were divided into early-treated group(n=24) and late-treated group(n=21). Lateral cephalograms were taken at the beginning and the end of treatment. Twenty-one measurements on hard and soft tissue were included.

RESULTSAfter treatment, SNA, ANB, NA-Apo, Wits, U1-SN, U1-NA, Overjet, UL-EP were significantly increased (1.0±1.9)°, (1.2±1.6)°, (2.6±4.2)°, (1.8±2.7) mm, (4.2±7.6)°, (2.6±7.5)°, (3.6±2.3) mm and (0.8±2.2) mm(P<0.05). OP-SN and IMPA were significantly decreased (1.5±3.7)°and (1.4±4.2)°(P<0.05). There were significant differences in SNA, ANB, UL-EP, IMPA, L1-NB between early-treated group and late-treated group(P<0.05).

CONCLUSIONSFR Ⅲ was suitable for the treatment of mild and moderate skeletal Class Ⅲ patients. The result was better in the early-treated patients than in late-treated ones.

Cephalometry ; Child ; Dentition, Mixed ; Female ; Humans ; Male ; Malocclusion, Angle Class III ; therapy ; Orthodontic Appliances, Functional ; Overbite ; etiology ; Time-to-Treatment ; Treatment Outcome