Root resorption caused by impacted permanent teeth. Case report

A case of severe external root resorption in several teeth caused by unerupted permanent teeth is presented along with the initial surgical treatment.     

Root development of rat tooth germs implanted in the tooth socket and in the subcutaneous tissue

Objective: This study was designed to investigate root development of a rat tooth germ implanted in a tooth socket or in a subcutaneous region. Materials and methods: Tooth germs of the upper left first molars in 2‐week‐old rats were extracted and implanted in the original tooth socket or in the subcutaneous region of the back. The upper right first molar was used as a control. The rats were fixed in weeks 1, 2, 4, 8 and 12. The root development was examined quantitatively with X‐ray radiographic morphometry. The cellular activity of producing matrix proteins was assessed using in situ hybridization for type I collagen. Results: Root development was observed in the implanted teeth in the tooth socket as also in the control teeth. In contrast, roots hardly developed in subcutaneously implanted teeth. Histology showed that periodontal ligaments were arranged around roots of implanted teeth in the tooth socket as around control teeth, but few periodontal ligaments were identified in the subcutaneous implantation. Dentin and cementum formed in both the implanted teeth as also in the control teeth and odontoblasts, cementoblasts and cementocytes expressed type I collagen. Conclusion: Tooth sockets may possess specific environments that allow root development of a tooth germ.     

Unerupted first permanent molar. Case report

A case of an unerupted first permanent molar in a nine-year-old child is described and the aetiology is discussed. Surgical intervention was selected as the treatment of choice and resulted in a satisfactory outcome.     

Treatment of traumatic injuries to an anterior tooth. Case report

A procedure is described in which a multi-disciplinary approach to restoration of a subgingivally-fractured anterior tooth is performed.     

Effects of antiresorptive medications on tooth root formation and tooth eruption in paediatric patients

Tooth eruption is a pivotal milestone for children's growth and development. This process involves with the formation of the tooth root, the periodontal ligament (PDL) and the alveolar bone, as the tooth crown penetrates the bone and gingiva to enter the oral cavity. This review aims to outline current knowledge of the adverse dental effects of antiresorptive medications. Recently, paediatric indications for antiresorptive medications, such as bisphosphonates (BPs), have emerged, and these agents are increasingly used in children and adolescents to cure pathological bone resorption associated with bone diseases and cancers. Since tooth eruption is accompanied by osteoclastic bone resorption, it is expected that the administration of antiresorptive medications during this period affects tooth development. Indeed, several articles studying human patient cohorts and animal models report the dental defects associated with the use of these antiresorptive medications. This review shows the summary of the possible factors related to tooth eruption and introduces the future research direction to understand the mechanisms underlying the dental defects caused by antiresorptive medications.     

Root fracture in immature tooth: report of a case

Abstract –  Root fracture injuries affect 0.5–7% of permanent teeth. Although this type of injury is rarely seen in teeth with immature root formation, the prognosis is generally good depending on the site of the fracture. A case report of horizontal root fracture in maxillary central incisor of an 8-year and 3-month-old girl and its treatment was presented.     

Root form and canal anatomy of maxillary first premolars in a southern Chinese population

Abstract Racial differences in dental crown morphology have long been recognized, but the frequency of genetically determined variations in root form and canal anatomy has not been established. Features of root and root canal morphology that occur at particularly high frequency in Mongoloid populations have not been systematically documented, and the implications that such features may have upon clinical endodontics have not been fully reported. In this study 100 maxillary first premolars extracted from Hong Kong Chinese patients were examined visually and radiographically. For each tooth, the number of roots, root canals, and apical foramina were noted. Sixty per cent of the maxillary first premolars examined were found to be single-rooted, but only 13% were found to have a single canal. The high frequency of single-rooted teeth with two canals suggests that the single-rooted condition represents a fusion, occurring in the relatively recent past, of two original roots.     

Re-attachment of original tooth fragment to a fractured crown. Case report

A procedure is described in which the fractured portion of a traumatized tooth was re-attached to the crown using the acid-etch composite resin technique. The restoration had functioned successfully when reviewed six months later. The benefits of the procedure are discussed.     

Class II division 1 malocclusion treated with extraction of upper first premolars: Case report

This report describes the treatment of a 13.7-year-old girl with a severe maxillary protrusion. She indicated Class II molar and canine relationship and showed 7-mm overjet, 0-mm overbite, and slight lower midline deviation with an unstable mandibular position. Treatment was started using a splint to stabilize the position of the mandible, followed by extractions of maxillary first premolars and fixed appliances to reduce lip protrusion. Molars were finished in a Class II relationship with canine guidance, and ideal overjet and overbite relationships were established. Also the final result was esthetically well balanced. The treatment results were stable 6 years after debonding.     

Multiple bilateral dens in dente involving all the premolars. Case report

Dens in dente, also known as dens invaginatus, dilated composite odontoma or deep foramen caecum, is a developmental malformation which usually affects maxillary incisor teeth, particularly lateral incisors. It may occur, however, in teeth anywhere within the jaws but other locations are comparatively rare. It can occur within both the crown and the root, although crown invaginations are more common. In this paper a case of multiple bilateral dens in dente involving maxillary and mandibular premolars is presented.     

Incomplete tooth fracture following root-canal treatment: a case report

AIM: To demonstrate the need for proper restoration of root-filled teeth. SUMMARY: Tooth fracture can be a sequel to root-canal treatment. It is associated with the removal of excessive amounts of the tooth substance during the instrumentation phase, the use of unnecessary force during obturation, or inadequate planning of the design of the eventual coronal restoration to include appropriate cuspal protection. Rarely, a fracture may be present in a tooth before treatment commences, but remains undetected. A case describing incomplete vertical tooth fracture of a root-filled mandibular first molar is presented.     

Supernumerary tooth in the maxillary sinus: Case report

The ectopic development of teeth has been reported in many locations including the nasal cavity, maxillary sinus and the chin. Ectopic teeth may be permanent, deciduous or supernumerary. A case is presented in which a supernumerary tooth erupted into the maxillary sinus of an 11 year old boy.     

Supernumerary tooth in the maxillary sinus: Case report

The ectopic development of teeth has been reported in many locations including the nasal cavity, maxillary sinus and the chin. Ectopic teeth may be permanent, deciduous or supernumerary. A case is presented in which a supernumerary tooth erupted into the maxillary sinus of an 11 year old boy.     

浅谈牙拔除术后抗菌药物的使用

牙拔除术是口腔颌面外科门诊最常见的手术。总体来看,其并发症的发生率较低,但由于患者群体基数庞大,因此出现并发症的患者群数量也相对较大,其中以术后局部感染最为常见,危害最大。抗菌药物的使用,是否能够降低局部感染的发生率;抗菌药物广泛使用的利弊,一直存在争议。本文仅对拔牙后是否使用抗菌药物以及抗菌药物使用的时机等问题进行初步探讨。     

乳牙根管系统的形态研究

目的 探讨乳牙根管形态的规律.方法 将一组完整的离体乳牙行透明标本制作后,再应用体视显微镜观察并记录其根管形态及其分类.结果 乳前牙除1颗为单双混合根管外,92%的牙体为单根单管型;上颌乳磨牙的根管形态均为三根管型,下颌乳磨牙的根管形态均为四根管型,并且根管侧枝和管间吻合常见.结论 乳前牙根管形态相对简单,而乳磨牙的...     

Histometric study of root resorption on human premolars following experimental replantation

Abstract – A histometric method was applied for evaluation of root resorption in 57 experimentally replanted teeth and 22 controls. Representative axiobuccolingual sections were selected for measurement of resorptions at a magnification of × 40. The frequency of root resorption in the control teeth was low. In replanted teeth marked resorptive activity elicited by the trauma appeared after 2 wk. The extent of active resorptions increased until the third postoperative week. On an average 14% of the root periphery was affected at this stage. After the sixth postoperative week progressive cement deposition took place in the resorption lacunae. Incidental ankylosis of the periodontal membrane also occurred from this observation time but there was no increase among the long-term groups.     

Surgical management of drooling. Case report

Drooling occurs when excessive quantities of saliva dribble from the opened mouth. This distressing condition affects many mentally handicapped patients who are unable to effectively clear their normal salivary flow by swallowing. Any method employed for the control of drooling must still allow a sufficient volume of flow for mastication, deglutition and oral hygiene. Surgery is generally indicated for marked or severe cases of drooling and Wilkie's operation involving redirection of the parotid flow into the oropharynx is the most commonly performed surgical procedure. This operation may be combined with bilateral removal of the submandibular salivary glands if the problem is severe.     

Compound composite odontome associated with impacted canine. Case report

A case of compound composite odontome is reported. The classification and aetiology of odontomes is briefly discussed.     

Dynamics of bone tissue formation in tooth extraction sites. An experimental study in dogs

OBJECTIVES: The aim of the present experiment was to study events involved in the healing of marginal, central and apical compartments of an extraction socket, from the formation of a blood clot, to bone tissue formation and remodeling of the newly formed hard tissue. MATERIAL AND METHODS: Nine mongrel dogs were used for the experiment. The fourth mandibular premolars were selected for study and were divided into one mesial and one distal portion. The distal root was removed and the socket with surrounding soft and mineralized tissue was denoted "experimental unit". The dogs were killed 1, 3, 7, 14, 30, 60, 90, 120 and 180 days after the root extractions. Biopsies including the experimental units were demineralized in EDTA, dehydrated in ethanol and embedded in paraffin. Serial sections 7 microm thick were cut in a mesio-distal plane. From each biopsy, three sections representing the central part of the socket were selected for histological examination. Morphometric measurements were performed to determine the volume occupied by different types of tissues in the marginal, central and apical compartments of the extraction socket at different intervals. RESULTS: During the first 3 days of healing, a blood clot was found to occupy most of the extraction site. After seven days this clot was in part replaced with a provisional matrix (PCT). On day 14, the tissue of the socket was comprised of PM and woven bone. On day 30, mineralized bone occupied 88% of the socket volume. This tissue had decreased to 15% on day 180. The portion occupied by bone marrow (BM) in the day 60 specimens was about 75%, but had increased to 85% on day 180. CONCLUSION: The healing of an extraction socket involved a series of events including the formation of a coagulum that was replaced by (i) a provisional connective tissue matrix, (ii) woven bone, and (iii) lamellar bone and BM. During the healing process a hard tissue bridge--cortical bone--formed, which "closed" the socket.