Z U F J D P T ! ! BALKAN JOURNAL OF STOMATOLOGY M ISSN 1107 - 1141 B JD H MP UP TUPNB Tooth Eruption: Topical and Systemic Factors that Influence the Process SUMMARY Vasiliki Boka, Anastasios K. Markopoulos, Several topical and systemic factors have been reported to influence Athanassios K. Poulopoulos the eruption of teeth. Some of the local lesions include eruption cysts, erup- Aristotle University, School of Dentistry tion sequestra, fibrous developmental malformations and dentigerous cysts. Department of Oral Medicine & The systemic factors include Down’s syndrome, cleidocranial dysostosis, Maxillofacial Pathology Thessaloniki, Greece hypothyroidism, hypopituitarism and achondroplastic dwarfism. All these lesions and factors generally influence the eruption of the primary, as well as the permanent dentition. The purpose of this review article is to present up-to-date aspects of these conditions. Keywords: Eruption cysts; Dentigerous Cysts; Down’s Syndrome; Cleidocranial REVIEW PAPER (RP) Dysostosis; Hypothyroidism; Hypopituitarism; Dwarfism, achondroplastic Balk J Stom, 2009; 13:11-14 Introduction erupting tooth. They are considered soft tissue analogues of the dentigerous cysts. Lately, eruption cysts are Numerous studies have been performed to understand described as a possible adverse effect of cyclosporine-A the process of tooth eruption better. The most common (CyA) administration during tooth eruption4. general symptoms during tooth eruption include anxiety There is a gender predilection; the male to female (15%), diarrhea (13%), a combination of the two (8%), ratio is 2:15,6. They usually appear in the region of fever1 and increased salivation2. Apart from general the molars7. Eruption cysts clinically appear as soft symptoms that end up to normal eruption of the teeth, translucent swelling in the gingival mucosa. Their colour several local and systemic factors have been reported varies between deep blue and azure7. to influence the eruption of teeth. The exact nature of Surface trauma may result in a considerable amount of the factors responsible for tooth eruption is not fully blood in the cystic fluid. Such lesions are sometimes referred understood. It is believed that these factors influence the as eruption haematomas. Their basic clinical characteristics matrix formation and the calcification process. are swelling, fluctuation and deep blue colour6. Pain may The most important local conditions that influence appear only if the cyst is traumatized7. Histologically, they tooth eruption are: eruption cysts, eruption sequestra, are characterized by non-keratinized, squamous epithelium fibrous developmental malformations and dentigerous lining in the cystic wall7. Differential diagnosis includes cysts. Systemic factors include Down’s syndrome, haematoma, amalgam tattoo, cysts and haemangioma8,9. cleidocranial dysostosis, hypothyroidism, hypopituitarism The treatment of the eruption cysts is surgical and and achondroplastic dwarfism. includes the excision of tissues over the crowns of the The purpose of this review article is to present the responsible teeth. In most cases, even this treatment is current aspects of these conditions. not necessary, because the cysts rupture and never appear again3. Eruption Cysts Eruption Sequestrum Eruption cysts occur within the mucosa overlying a tooth that is about to erupt3. They develop as a result of The eruption sequestrum usually appears during the separation of the dental follicle from around a crown of an eruption of the first permanent molars. Intraorally, the 12 V. Boka et al. Balk J Stom, Vol 13, 2009 lesions presents as a small hard tissue fragment, white in Inflammatory Dentigerous Cysts colour, and with bone-like hardness on the occlusal surface of the mandibular second molar that was erupting10. Inflammatory dentigerous cysts are the most common Histopathologically, the fragments consist of necrotized type of developmental odontogenic cysts and mostly they cortical bone11. Studies involving X-ray micro-analyzer are found in the mixed dentition24. They are usually single revealed that the percentages of calcium and phosphorous and they are located in the posterior mandible25. They (by weight) were 78.41% and 21.59%, respectively, with are associated with the roots of non-vital deciduous teeth a calcium to phosphorous ratio of 3.63, which was higher and the crown of their unerupted permanent successors26. than that seen in normal osseous tissue11. Generally, the The cysts are not painful except in the case of secondary sequestra have little clinical significance as they can appear infection, or unless their size has created a pathological and disappear. However, they may retain plaque in close fracture24. association with the newly erupting tooth12. The retained There are 2 leading theories about the formation 24 eruption sequestrum may lead to pericoronitis or pit and of dentigerous cysts . The first begins with fluid fissure caries13. In dental practice the presence of multiple accumulation between the reduced enamel epithelium developmental dental anomalies expressing simultaneous and the crown of the tooth. The other theory begins with defects in different stages of tooth development should a breakdown of the stellate reticulum, which forms a fluid between the inner and outer enamel epithelium. raise suspicion of possible manifestation of an underlying Radiographically, the tooth may be displaced: it is systemic abnormality, such as Ehlers-Danlos syndrome14. not surprising to see teeth displaced to the condylar neck, Treatment is not always necessary. Surgical removal the nasal floor or high in the maxillary sinus approaching is usually chosen only if it is usually traumatized or the orbit24. Histologically, they are composed of a thin annoys the patient2. connective tissue wall lining the lumen. The epithelium is usually parakeratinized or orthokeratinized. Rete peg formation is usually absent and an inflammatory cell infiltration of the connective tissue is common. In about Fibrous Developmental 50% of cases, dentigerous cysts can cause resorption of Malformation the adjacent unerupted teeth. Treatment of choice is the extraction of the infected In most cases, fibrous developmental malformation deciduous tooth and continuous drainage of the cyst27. manifests as enlargement of the gingiva, often correlated Simultaneous with the eruption of the permanent with the eruption of deciduous or permanent teeth15. tooth, ossification of the bony defect can take place28. Gingival fibromatosis may be familial or idiopathic. The reparatory process is completed in 1-2 years26. The familial variations may occur as isolated finding Marsupialization is less ideal; it runs the risk of allowing an 24,29 or in association with hereditary syndromes, such as ameloblastoma in situ . This treatment is indicated only Zimmermann-Laband syndrome, Rutherford syndrome or in 2 situations: (1) if it will allow a tooth to spontaneously multiple hamartomas. erupt or to be orthodontically guided into a functional Tagaki et al16 described 6 categories of fibrous position in the arch; or (2) if the surgeon identifies a developmental malformation; (1) isolated familial gingival realistic risk of damaging developing teeth or neurovascular bundles during the enucleation24. fibromatosis; (2) isolated idiopathic gingival fibromatosis; (3) gingival fibromatosis associated with hypertrichosis; (4) gingival fibromatosis associated with hypertrichosis and mental retardation, or epilepsy, or both; (5) gingival Down’s Syndrome fibromatosis associated with mental retardation, or epilepsy, or both; (6) gingival fibromatosis associated with Down’s syndrome (trisomy 21) is one of the hereditary syndromes. congenital pathologic conditions in which delayed eruption In most cases the enlargement begins before the age of the teeth is frequently observed. Various studies in of 20. The gingiva is firm, normal in colour and covered children with Down’s syndrome have shown that delayed 17-21 by a smooth surface . Histopathologically, fibrous tooth eruption is common, but sporadic30,31. The eruption developmental malformations consist of poorly cellular, usually follows an abnormal sequence and some of the richly collagenous fibrous connective tissue underneath deciduous teeth may be retained until the age of 15 years. a normal or acanthotic epithelium. Mild peri-vascular The eruption abnormalities are associated with retardation chronic inflammation and small foci of dystrophic in the growth of maxilla and mandible. A reduction of the calcification may be observed22. anterior skull base and protrusion of lower incisors is often Treatment is required only if the lesion annoys the observed, which is related to a tendency to anterior cross- patient. Surgical removal is the treatment of choice23. bite and, to a lesser extent, to diminished overbite32. Balk J Stom, Vol 13, 2009 Factors that Influence Tooth Eruption 13 Cleidocranial Dysplasia often results in hypopituitarism. The dental findings of the syndrome include delayed eruption of the teeth. Cleidocranial dysplasia is a hereditary disorder Hutchinson-Gilford disease or progery is caused by characterized by abnormal clavicles, delayed fusion of anterior pituitary lobe malfunction. Delayed eruption of the bones in the skull, extra teeth and short stature. Other the teeth is also included in the clinical findings of this bones, such as the ribs, pelvis and bones of the hands and disease. feet may also be affected. Most patients with cleidocranial dysplasia do not