Effects of diazepam on orthodontic tooth movement and alveolar bone cAMP levels in cats

Development of a tooth movement model of root resorption during intrusive orthodontic treatment

There is a high risk of external apical root resorption (EARR) following the application of intrusive orthodontic forces to the apical root. However, there is a lack of suitable animal models to study this phenomenon in depth. This study compared the usability of three different types of loops, namely, vertical helical loop, box loop, and L loop, for preparing a rat model of orthodontic tooth movement with invasive forces. Results showed a significant downward movement in the first molar of the rat after L loop placement for 14 days. Three-dimensional reconstructed images showed root resorption and length shortening on the apical root and decreased bone volume and trabecular thickness in the alveolar bone under compression. Histological staining revealed odontoclasts on the root resorption fossa. This study showed that orthodontic tooth movement using the L loop provides an effective experimental animal model of EARR.

Dose-related effects of extracorporeal shock waves on orthodontic tooth movement in rabbits

The purpose of this animal study is to investigate the quantitative effects of extracorporeal shock waves applied at two different impulses and with two different applicators on orthodontic tooth movement. Thirty-five New Zealand rabbits were randomly divided into five groups (n = 7): the four experimental extracorporeal shock wave groups-focused/500 impulses, focused/1000 impulses, unfocused/500 impulses, and unfocused/1000 impulses-and the control group. Orthodontic tooth movement was achieved by application of reciprocal force between two maxillary incisors. In the experimental groups, animals received 500 or 1000 impulses of extracorporeal shock waves at 0.19 mJ/mm² with focused or unfocused applicators depending on the group to which they belonged. These experiments were conducted on days 0, 7, and 14. Orthodontic tooth movement was measured with 0.01 mm accuracy at one-week intervals. On days 7 and 21, the bone-specific alkaline phosphatase levels were measured from blood samples. After 21 days, the animals were sacrificed and the area between the two maxillary incisors was stereologically examined. Orthodontic tooth movement in the focused/500 impulses and focused/1000 impulses groups was significantly increased compared to the control group. A significant difference in bone-specific alkaline phosphatase levels between the unfocused/500 impulses and control groups was found at 21st day. Stereological analysis showed that there were significant increases of the formation of new bone, connective tissue, and vessels in the experimental groups. The application of extracorporeal shock waves, especially with a focused applicator, could accelerate orthodontic tooth movement.

Systematic review of biological therapy to accelerate orthodontic tooth movement in animals: Translational approach

OBJECTIVES

To systematically review and evaluate what is known regarding contemporary biological therapy capable of accelerating orthodontic tooth movement (OTM) in animal model.

MATERIALS AND METHODS

MedLine, Scopus, Web of Science and OpenGrey were searched without restrictions until June 2019. Following study retrieval and selection, relevant data was extracted using a standardized table. Risk of bias (RoB) assessment was performed using the Systematic Review Centre for Laboratory Animal Experimentation (SYRCLE) tool.

RESULTS

Fifty-one animal studies were included. Two biological therapies were identified as capable of accelerating the OTM: chemical methods (49 studies) and gene therapy (2 studies). The main substances that increased the OTM rate were cytokines (13 studies), followed by growth factors (6 studies) and hormones (5 studies). Most studies were assessed to be at unclear or high RoB. The application protocols, measurement and reporting of outcomes varied widely and methodologies were not adequately reported.

CONCLUSIONS

Although biological therapies to accelerate OTM have been widely tested and effective in preclinical studies, the validity of the evidence is flawed to support translational of these results. There is a need for well-designed experimental studies to translate these methods for clinical field.

Medication and orthodontic tooth movement

As any pharmaceutical substance may influence the events associated with orthodontic tooth movement, it is of importance for the clinician to be able to recognize any prospective patient's history and patterns of medicinal consumption. This review presents the effects of various commonly prescribed medications on the rate of orthodontic tooth movement. The article concludes that it remains, to a degree, unclear which types of medication may have a clinically significant effect in everyday clinical scenarios. However, since both prescription and over-the-counter medication use have recently increased significantly among all age groups, good practice suggests that it is important to identify patients consuming medications and consider the possible implications in orthodontic therapy.

Does common prescription medication affect the rate of orthodontic tooth movement? A systematic review

Background

As the taking of any medication may theoretically affect the complex pathways responsible for periodontal tissue homeostasis and the events leading to orthodontic tooth movement, it is considered important for the orthodontist to be able to identify prospective patients' history and patterns of pharmaceutical consumption.

Objective

To systematically investigate and appraise the quality of the available evidence regarding the effect of commonly prescribed medications on the rate of orthodontic tooth movement.

Search methods

Search without restrictions in eight databases and hand searching until June 2017.

Selection criteria

Controlled studies investigating the effect of commonly prescribed medications with emphasis on the rate of orthodontic tooth movement.

Data collection and analysis

Following study retrieval and selection, relevant data was extracted and the risk of bias was assessed using the SYRCLE's Risk of Bias Tool.

Results

Twenty-seven animal studies, involving various pharmacologic and orthodontic interventions, were finally identified. Most studies were assessed to be at unclear or high risk of bias. The rate of orthodontic tooth movement was shown to increase after the administration of diazepam, Vitamin C and pantoprazole, while simvastatin, atorvastatin, calcium compounds, strontium ranelate, propranolol, losartan, famotidine, cetirizine, and metformin decreased the rate of orthodontic tooth movement. No interference with the rate of orthodontic tooth movement was reported for phenytoin, phenobarbital and zinc compounds, whereas, inconsistent or conflicting effects were noted after the administration of L-thyroxine, lithium compounds, fluoxetine and insulin. The quality of the available evidence was considered at best as low.

Conclusions

Commonly prescribed medications may exhibit variable effects on the rate of orthodontic tooth movement. Although the quality of evidence was considered at best as low, raising reservations about the strength of the relevant recommendations, the clinician should be capable of identifying patients taking medications and should take into consideration the possible implications related to the proposed treatment.

Registration

PROSPERO (CRD42015029130).

A influência de medicamentos na movimentação ortodôntica: uma análise crítica da literatura

Neste trabalho analisou-se criteriosamente a literatura pertinente sobre a influência de medicamentos na movimentação dentária induzida, avaliando os métodos experimentais para correlacioná-los com a aplicabilidade e extrapolação para a clínica ortodôntica. Devido aos trabalhos experimentais serem feitos em animais, que têm um tempo de vida curto, as doses dos medicamentos são elevadas e os períodos de administração muito longos. Portanto, não se pode afirmar sobre qualquer alteração na movimentação dentária induzida causada por algum tipo de medicamento que o paciente faça uso durante o tratamento ortodôntico.

Detection of apoptosis during orthodontic tooth movement in rats

Experimental evidence suggests that cellular changes and tissue turnover occurs in the periapical tissue during tooth movement. The possible role of apoptosis in tooth movement has never been investigated. The purpose of this study was to show whether apoptosis plays any role in orthodontic tooth movement. A sample of 21 adult male Sprague-Dawley rats was divided into 4 groups. Orthodontic appliances were attached to the rats for various times-to group I (n = 6) for 3 days, to group II (n = 6) for 1 week, and to group III (n = 6) for 2 weeks. Rats in group IV (n = 3) had appliances but no force and served as the control group. At the end of the observation period, the animals were killed and tissue blocks of involved teeth were processed and prepared for TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling) reaction. TUNEL-positive cells from selected areas on each slide were counted and compared by means of an analysis of variance. Group I demonstrated a significantly higher (P <.05) number of positive cells. This suggests that the maximum apoptosis occurs approximately 3 days after the application of the appliance.

Effect of a resorbable bone graft material on orthodontic tooth movement through surgical defects in the cat mandible

beta-Tricalcium phosphate ceramic, a resorbable synthetic bone material, was implanted into surgically created alveolar defects mesial to the mandibular first premolars of 12 adult male cats. Similar defects on the contralateral side were allowed to heal naturally. Six weeks later, nickel-titanium coiled springs were ligated between the mandibular canine and first premolar on both sides and activated to deliver 100 g of force. The distance between the canine and first premolar was measured with dial calipers at 0, 3, 6, and 9 weeks after appliance placement. Regression analysis of amount of tooth movement between the two teeth showed no significant difference between grafted and control sides. This suggests that placement of a resorbable synthetic bone material may have useful applications in situations where loss of alveolar width following extractions may compromise orthodontic tooth movement.