pedo lec 14.pdf

Lec 14 Dr. Rawaa B. Fadhel B.D.S M.Sc. Types of space maintainers Pedodontics Types of space maintainer 1- removable space maintainer  They are space maintainers that can be removed and inserted into the oral cavity by the patient.  It can be functional or non functional and are bilateral most of...

Lec 14 Dr. Rawaa B. Fadhel B.D.S M.Sc. Types of space maintainers Pedodontics Types of space maintainer 1- removable space maintainer  They are space maintainers that can be removed and inserted into the oral cavity by the patient.  It can be functional or non functional and are bilateral most of the time Types of removable space maintainers    A- acrylic partial denture B- complete denture; given when there is loss of all teeth as in rampant caries or ectodermal dysplasias C- removable distal shoe space maintainer; act as acrylic immediate partial denture with distal shoe extension into the alveolus. It is used when fixed distal shoe cannot be placed due to many missing teeth 2- fixed space maintainer  They can be unilateral or bilateral, functional or nonfunctional, active or passive space maintainer the are designed to be cemented on to the tooth and cannot be removed by the patient Types of fixed space maintainer  1- band and loop, crown and loop space maintainer  2-passive lingual arch space maintainer  3- Transpalatal bar space maintainer  4- Nance palatal arch space maintainer  5- Distal shoe space maintainer Band and loop space maintainer  They are unilateral, fixed, nonfunctional and passive space maintainer Indications: 1- used when single tooth is missing in posterior segment 2- it can be given in bilateral posterior tooth loss, before the eruption of permanent anterior incisors in the mandible, where two band and loop space maintainer can be given instead of passive lingual arch space maintainer Contraindications of band and loop  high caries activity  marked space loss  more than one adjoining teeth missing Disadvantages of band and loop space maintainer      nonfunctional Doesn‟t prevent continued supereruption of opposing tooth Caries check is difficult Oral hygiene maintenance is difficult The loop may slip from the position and impinge on gingiva occlusal rests given to the loop that rest on the occlusal surface of the mesial abutment tooth prevents this disadvantage Technique A stainless steel band is fitted on the tooth  Impression of dentition and band, the band is removed from the tooth and seated in the impression  In the stone model of impression, a piece of 0.036- inch steel wire is used to prepare the loop and soldered to the band  Band and loop appliance is cemented intraorally  The stainless steal crown and loop maintainer is a modification of band and loop, it may be used: 1- if posterior abutment tooth has extensive caries and requires crown 2- if abutment tooth has had vital pulp therapy, in which case it is desirable to protect with full coverage technique  The steel crown should be prepared  Before cementation, compound impression is made  The crown removed from tooth and seated in the impression  The stone model is prepared from impression  A piece of 0.036 inch steal wire is used to prepare the loop Passive lingual arch appliance  It is a bilateral, fixed, non functional, passive space maintainer for mandibular arch  Indicated when there is bilateral loss of molars after the eruption of permanent incisors in the lower arch  The right and left first permanent molar are banded in lower segment  A U shaped arch wire extend from lingual surface of molar bands to lingual surface of anterior teeth above the cingulum  It prevents the mesial movement of posterior teeth and collapse of anterior segment Nance palatal arch space maintainer  It is bilateral, fixed, passive and nonfunctional space maintainer for the maxillary arch  The first permanent molars are banded  The arched wire extends from the palatal surface of one molar band to the other, anteriorly it extends up to the rugae area and is embedded in an acrylic bottom that firmly placed on rugae provide good anchorage  Indicated when there is bilateral missing deciduous molars in upper arch  It can be made active by incorprating “U” loop to the wire. Opening the loop causes distalization of first permanent molar  The acrylic button may irritate the soft tissue and this appliance may not be suitable for patients allergic to acrylic Transpalatal bar space maintainer  Indicated for maxillary teeth when one side of the arch is intact and several primary teeth are missing in the other side.  In this case, the rigid attachment to the intact side usually provide enough stability for space maintainer  however, when primary molars have been lost bilaterally, both permanent molars tip mesially with transplalatal bar , nance appliance is preferred in this situation Distal shoe space maintainer  It is unilateral, fixed, non functional and passive space maintainer. It is an intra-alveolar appliance, in which a portion of appliance is extending into alveolus Indications of distal shoe :  When there is premature loss of second deciduous molar before eruption of first permanent molar  When there is one tooth is lost on one quadrant as the strength of appliance is limited. So, when both the first and second deciduous molars are missing in the same quadrant, removable distal shoe is preferred Contraindications of distal shoe      inadequate abutments due to multiple loss of teeth Poor oral hygiene Missing permanent first molar Lack of patient and parent cooperation Presence of medical conditions such as blood dyscrasias, congenital cardiac defect predisposing to subacute bacterial endocarditis, history of rheumatic fever, diabetes, general debilitation Premature loss of deciduous teeth Loss of primary incisors  The main concern is based on esthetic, speech and function 1- loss of mandibular primary incisors:   Early loss of lower primary incisors is generally due to ectopic eruption of permanent incisors in reflecting excessive incisor liability. The loss of lower incisors in other circumstances, such as trauma, advanced caries or extraction of neonatal tooth, may result in anterior space loss if it occur before primary canine stabilization is realized 2- loss of maxillary primary incisors Don‟t generally result in decrease upper upper intercanine dimensions if the incisor loss occurs after primary canine have erupted into occlusion at approximately 2 years of age The major consequence of early loss of maxillary primary incisors is: 1- delayed eruption timing of permanent successors as reparative bone and dense connective tissue cover the site 2- unattractive appearance 3- potential development of deleterious habits (e.g., tonguethrust swallow, forward resting posture of the tongue) 4- improper pronunciation of fricative sounds such as „‟s‟‟ and „‟f‟‟ may be of concern following premature loss of primary incisors management A- removable appliance:  An anterior appliance incorporating artificial primary teeth may be considered to satisfy aesthetic and functional needs, acrylic partial denture have been successful in replacement of single and multiple maxillary primary incisors B- fixed appliance  A fixed option may be considered using primary incisors denture teeth secured from a rigid stainless steel wire (0.036- or 0.040-inch) extended to bands or stainless steel crowns on the primary molars, a so called „‟hollywood‟‟ bridge Premature loss of primary canine 1- mandibular primary canine  Most often due to ectopic eruption permanent lateral incisors, early loss of primary mandibular canine is a significant indicator of a tooth size arch discrepancy The consequence of early loss of lower primary canine are: A- unilateral loss of lower primary canine: This is frequently followed by:  shift in midline toward side of loss  Lingual collapse incisor segment  Possibly deepening of bite B- if ectopic eruption involves bilateral loss of both lower primary canines, this is followed by:  pronounced lingual inclination and distal drifting of permanent incisors  Deepening of overbite  Increased overjet 2- maxillary primary canine  The ectopic loss of maxillary primary canine occur less frequently than does mandibular loss, when it occur, ectopic loss of maxillary primary canine typically reflect a very distal eruptive displacement of permanent lateral incisors and not necessarily a significant tooth mass problem, 2- maxillary primary canine the following may occur:  resultant crowding and blockage of permanent canine because it erupt too late in normal transition  Early loss of maxillary primary canine is an indicator of early orthodontic treatment with an understanding that the child is a definite candidate for comprehensive orthodontic intervention Management A- If one primary canine is lost during incisor eruption, it may be desirable to extract the contralateral primary canine to maintain symmetry Crowding problems requiring such intervention strongly indicate a significant arch length deficiency that will become grossly evident permanent canine and premolar eruption B- lingual holding arch may be used with spur attachments to control incisor positioning and prevent encroachment on permanent canine eruption positions when primary canines are lost prematurely