Use of an intraoral scanner to evaluate orthodontic treatment for dental malocclusion in a dog.

OBJECTIVE: In human dental practice, intraoral scanners (IOSs) are increasingly used to evaluate the oral cavity. However, there have been no reports concerning evaluation of the canine oral cavity using IOSs in veterinary dentistry. In this case, optical impressions obtained with an IOS were used for 3-D evaluation of the orthodontic treatment outcome. Additionally, few reports have addressed the optimal orthodontic force for canine teeth. Therefore, this case explored whether sufficient tooth movement into the extraction site could be achieved with a lighter orthodontic force than previously reported. ANIMAL: An 8-month-old spayed female dog. CLINICAL PRESENTATION, PROGRESSION, AND PROCEDURES: A retained right maxillary third deciduous incisor (503) caused distoversion of the right maxillary third permanent incisor (103), leading to dental malocclusion that involved contact between 103 and the right mandibular canine teeth. TREATMENT AND OUTCOME: All retained deciduous teeth were extracted. Mesial tipping movement of 103 into the extraction site of 503 was achieved with light orthodontic force using an elastomeric chain. An IOS was used to construct 3-D optical impression data from oral stone models taken before and after treatment, and tooth movement was evaluated. The results showed that 103 had sufficient tipping movement and no anchorage loss; comfortable occlusion was achieved. In addition to crown length extension, labioversion and mesioversion of maxillary incisors (other than 103) were observed. CLINICAL RELEVANCE: Detailed intraoral evaluation with optical impressions was beneficial in the orthodontic treatment of a dog. Light orthodontic force may be sufficient for movement into the extraction site.

Effect of ovariectomy-induced osteoporosis on the amount of orthodontic tooth movement: a systematic review of animal studies.

BACKGROUND: Understanding the impact of osteopenia and osteoporosis on orthodontic tooth movement could be of benefit to the orthodontist, but research in humans presents practical and ethical problems. The ovariectomized animal model could provide useful information on osteoporosis. OBJECTIVE: To compare the amount of tooth movement during or after the application of orthodontic forces between ovariectomized animals and control or sham-operated subjects. SEARCH METHODS: Unrestricted searches in seven databases and manual searching of the reference lists in relevant studies were performed up to February 2021 (PubMed, Central, Cochrane Database of Systematic Reviews, Scopus, Web of Science, Arab World Research Source, ProQuest Dissertations, and Theses Global). SELECTION CRITERIA: We searched for studies quantitatively comparing the amount of tooth movement during or after the application of orthodontic forces between ovariectomized animals and control or sham-operated subjects. DATA COLLECTION AND ANALYSIS: Following study retrieval and selection, relevant data were extracted, and the risk of bias was assessed using the SYRCLE's Risk of Bias Tool. Exploratory synthesis and meta-regression were carried out using the random effects model. RESULTS: Thirteen studies were finally selected and no specific concerns regarding bias were identified. During the active period, ovariectomy was associated with a statistically significant acceleratory effect on the rate of orthodontic tooth movement compared to non-treated rats (3 weeks; 4 studies, 0.15 mm more movement in the ovariectomized rats; 95 per cent confidence interval: 0.10-0.19; P = 0.000). Exploratory meta-regression showed that this difference could increase over time. Following force discontinuation, no statistically significant differences were observed [3 weeks; 1 study (median ± SE), Ovariectomy group: 0.30 ± 0.04 mm; Sham operation group: 0.18 ± 0.03; P = 0.1558]. CONCLUSIONS: Ovariectomy-induced osteoporosis may affect the rate of orthodontic tooth movement. Although animal studies should be approached with caution regarding their translational potential, the safe practice would suggest that one should consider potential implications. REGISTRATION: PROSPERO (CRD42018118003).

Experimental tooth movement temporally changes neural excitation and topographical map in rat somatosensory cortex.

During orthodontic treatment, binding teeth, may change the topographically organized representation of teeth in the cerebral cortex. To test the hypothesis that experimental tooth movement (ETM) changes the somatotopy of an individual tooth arrangement in the somatosensory cortex, we examined the spatiotemporal features of cortical excitatory propagation in response to mechanical stimulation of the maxillary incisor or molar using optical imaging in late adolescent rats without or with ETM. The ETM models consisted of 1d, 3d, and 7d ETM in which a closed-coil spring was ligated between the maxillary first molar and incisors. In controls, incisor and molar mechanical stimulation evoked excitation in the rostral and dorsocaudal regions of the primary somatosensory cortex (S1), respectively. In addition, the secondary somatosensory cortex and insular oral region (S2/IOR) were also activated. Incisor stimulation-induced excitatory regions in S1 of 3d and 7d ETM shifted without changing the maximum excitatory area or peak amplitude; the incisor stimulation-responding region moved toward the dorsocaudal region, which responded to molar stimulation in the control. This shift in excitatory region was not observed in 1d ETM. One day after removal of the coil spring that was attached for 6 days, the excitatory region shift in S1 was recovered to the control region. On the other hand, 1d ETM exhibited facilitation of the excitatory area and peak amplitude upon molar stimulation, and the facilitation of excitatory propagation disappeared in 3d and 7d ETM. These results may explain the clinical finding that abnormal sensation temporally occurs during orthodontic treatment.

Treatment of Bignathic Malocclusions With Multistage Active Force Orthodontic Movements in a Cat.

Abstract Untreated malocclusions may lead to negative oral health sequelae including, but not limited to, pain, dental trauma, periodontal disease, and endodontic disease. Thus, orthodontic treatments of malocclusion in companion animals are often pursued for reasons other than cosmesis. Treatment may provide a pain-free, functional occlusion with the opportunity for the best possible long-term oral health. This report describes the multistage orthodontic treatment of a bignathic malocclusion in a cat, highlighting the complexities and complications that may arise with orthodontic movement of multiple teeth.

Staged orthodontic movement of mesiolinguoversion of the mandibular canine tooth in a dog.

A 10 mo old Sapsaree dog presented for evaluation and treatment of malocclusion causing palatal trauma. A class III malocclusion with mesiolinguoversion of the 404 and enamel hypoplasia was diagnosed based on oral examination. It was decided to attempt orthodontic correction of the mesiolinguoverted tooth using an elastic chain and inclined bite plane technique with crown restoration of the enamel hypoplasia teeth. One year after the orthodontic correction and composite removal, the mesiolinguoverted right mandibular canine tooth was moved to an acceptable location within the dental arch and the locally discolored right maxillary canine tooth was vital.

Thermoplastic inclined plane aligner for correction of bilateral mandibular canine tooth distoclusion in a cat.

Mandibular brachygnathia was the etiology for moderate mandibular distoclusion and bilateral palatal canine cusp penetrations in a kitten. The course of treatment included deciduous canine tooth exodontia, tooth extensions, and ultimately, aligners that incorporated inclined planes fabricated from a thermoplastic sheet that was "indirectly" vacuum thermoformed over a dental model. The thin, flexible aligners fit over the rostral maxillary teeth and palate, and were retained by a snug fit on the slightly divergent maxillary canine teeth. Advantages over "directly" applied composite inclined planes include: serial gradations of angulations for more gradual tooth movement, elimination of dental trauma from composite adhesions and removals, owner-removable and cleanable appliances, and a single anesthetic event required for dental impressions. Five progressively angled aligners were used sequentially over a 3-month period to achieve atraumatic "clinical" neutroclusion of the rostral dentition.

Time-lapse observation of rat periodontal ligament during function and tooth movement, using microcomputed tomography.

The aim of this study was to observe the time-lapse changes in the rat periodontal ligament (PDL) during function and tooth movement. Under Nembutal anaesthesia, time-lapse changes in the thickness of the PDL of the first molars were investigated in five 12-week-old adolescent rats with microcomputed tomography. Three-dimensional (3D) images were reconstructed from the data. Histological observation was also performed, using undecalcified frozen sections of the maxillary first molar area. The PDL appeared as a radiolucent furrow on the 3D images. A slight change in the thickness of the PDL was observed 1 hour after initiation of orthodontic force loading, which became significant after 6 hours, with the appearance of pressure-tension zones during the tooth movement. These changes were more significant 3 days after orthodontic loading. Histological observation of the lingual cervical PDL (pressure zone) in nine 12- to 13-week-old rats demonstrated that the periodontal space had become narrow and the cellular elements appeared to be densely packed in the narrowed PDL 6 hours after orthodontic loading. Degeneration of tissues appeared 3 days after loading. Observation of the buccal cervical PDL (tension zone) demonstrated that the PDL was extended 6 hours after orthodontic force loading, and the extension continued for up to 3 days. Alkaline phosphatase activity was distributed in the PDL, except for the degenerating tissues in the pressure zone 3 days after loading. The results suggest that the periodontal reaction was initiated within 6 hours after orthodontic force loading, which was related to the structural changes of the PDL. The changes probably induced an early response in individual cells of the PDL.

Use of a synthetic bone substitute to retard molariform tooth drift after maxillary tooth loss in ponies.

OBJECTIVE: To evaluate the effect of alveolar bone substitute on post-extraction drift of maxillary cheek teeth in ponies. STUDY DESIGN: In vivo longitudinal experimental study. ANIMALS: Five ponies (5-7 years) with a healthy dentition. METHODS: Both maxillary 4th premolar teeth (Triadan 08) were surgically removed. One alveolus was filled with a biocompatible non-resorbable bone substitute (Bioplant 24), whereas the other healed by second intention. A polyvinylsiloxane plug and spring wire isolated the bone substitute from the oral environment. Pathologic changes to dentition and adjacent soft tissue were recorded. Tooth drift was calculated after 1 and 2 years. RESULTS: At 1 month, bone substitute material was incorporated into healthy tissue. Tooth drift was observed but differed significantly between control and treated sides at 2 years (P<.01). For both techniques, tooth drift differed significantly between years 1 and 2 (P<.001). Total drift in control arcades for year 1 was 10.69+/-2.12 mm and for year 2 was 9.08+/-0.87 mm, whereas for bone substitute arcades it was 9.90+/-1.60 mm for year 1 and 5.60+/-1.78 mm for year 2. CONCLUSIONS: Partial tooth replacement therapy after maxillary P4 extraction provided good healing in the immediate post-surgical phase. Alveolar filling with bone substitute material significantly slowed post-extraction tooth drift but did not stop it completely. Clinical Relevance- Important changes occur in equine dentition after maxillary cheek teeth removal. Further longer term observations are needed to fully validate study findings.

Fundamentals of small animal orthodontics.

The basic principles and concepts that govern the discipline of orthodontics are explored. The movement of teeth is mediated primarily through the periodontal ligament. When the periodontal ligament is stretched, bone apposition occurs. Conversely, in areas of compression, bone resorption occurs. The subject tooth moves in the direction of the force. The orthodontist must be cognizant of the prevailing ethical guidelines and the functional needs of the patient.

Surgical exposure and orthodontic extrusion of an impacted canine tooth in a cat: a case report.

A 7 month-old, male domestic shorthaired cat was referred because of facial swelling, an operculated cystic oral mass, and impaction of the associated maxillary left canine tooth. Surgical exposure and realignment failed to result in eruption. Surgical reexposure and orthodontic extrusion resulted in a functional alignment of the tooth within the dental arch. Follow up evaluations over the 5 ensuing years indicated persistence of the facial deformation, no evidence of ameloblastic biotransformation, and a healthy tooth.

Management of lingually displaced mandibular canine teeth in five bull terrier dogs.

Lingually displaced mandibular canine teeth (304, 404) were treated by applying inclined planes in five bull terrier dogs aged 10-19 months. The inclined planes produced interrupted tipping forces and were left in place for 3 weeks. The orthodontic movement technique successfully resolved the malocclusions. In two cases the treatment had to be repeated, perhaps because the animals were 10 and 12 months old and the device was removed too early. Canine teeth occlusion was normal in all five dogs when last examined 3 months following completion of treatment.

Efeito da prostaglandina E1 e da indometacina na movimentaçäo ortodôntica em cäes: estudo clínico e histológico / Clinical and histologic observations on prostaglandin and indometacin effects on orthodontic movement in dog

Os efeitos da administraçäo local de prostaglandina e da indometacina sobre a movimentaçäo de dentes de cäes, foram examinados e possíveis alteraçöes no tecido periodontal, estudados. Nove cäes foram submetidos a extraçäo dos incisivos mediais superiores e após a cicatrizaçäo, instalado um aparelho ortodôntico com força contínua de 250 gramas para traçäo mesial dos incisivos intermédios. Os animais, divididos em 03 grupos, receberam injeçöes de prostaglandina (grupo I); indometacina (grupo II) e soro fisiológico (grupo III). Nos três grupos estudados houve movimentaçäo dos incisivos intermédios, mas os animais que receberam injeçäo de prostaglandina, apresentaram maior movimentaçäo dos incisivos para a mesial, do que os animais dos grupos que receberam soro fisiológico e indometacina. Histologicamente, os animais que receberam prostaglandina, apresentaram aumento do número de osteoclastos, com aumento das áreas de reabsorçäo e de vasos sanguíneos, enquanto que no grupo onde os animais receberam injeçöes de indometacina e soro fisiológico, o número de osteoclastos e as áreas de reabsorçäo, foram menores

Orthodontics for the dog. Treatment methods.

This article considers the prevention of orthodontic problems, occlusal adjustments, simple tooth movements, rotational techniques, tipping problems, adjustment of crown height, descriptions of common orthodontic appliances, and problems associated with therapy.

Orthodontics for the dog. Bite evaluation, basic concepts, and equipment.

Evaluation of canine occlusion (an occlusal evaluation table is included), growth patterns of the head, basic concepts of orthodontics such as how teeth move, length of treatment, and limits to movements, and equipment and materials are considered in this article.