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Fig.1.Patient’sinitial fullface Fig.5.Fullfaceclosed mouth Fig. 6. Full face closed mouthwithincreaseof 5mminVDO Fig.2.Upperanterior teethshowing centrelineshift Fig.7.Upperdiagnosticwax-up Fig.12.Upper toothpreps Fig.10.Upperteethaftercrownlengthen- ing Fig.15.Finalupperanteriorcrowns Fig.3.Lowerwornanterior teeth Fig.8.Lowerdiagnosticwax-up Fig. 13. Prep guide when prepping lower teeth Fig. 11. Prep guide when prepping upper teeth Fig.16.Finallowercrowns Fig.4.Presentingsmilewithcentre lineshift Fig. 9. Poor width/length ratio of the up- per teeth Fig.14.Lower toothpreps Fig.19.Finalfullfacesmile showing increase in VDO andyoungerappearance Fig.17.Upperrestoredarch–occlusal view Fig.20.Initialpresentingsmile Fig.18.Finalsmilecloseup Fig.21.Edge-to-edgeocclusioninICP Dental Tribune Middle East & Africa Edition | 5/2016 18 restorative AdvancedRestorativeTechniquesandtheFull MouthReconstruction.VerticalDimension AndChangesDuringRestorativeTreatment.Part5 ByProf.PaulA.Tipton,UK A highly respected specialist in Pros- thodontics,Paulhaspublishedmany scientific articles in the dental press and is an expert lecturer in his field with Tipton Training Academies in Manchester,Leeds,LondonandDub- lin. AftergaininghisMastersDegree inConservativeDentistryin1989,he wasawardedtheDiplomainGeneral Dental Practice by the Royal College of Surgeons four years later and re- ceived Specialist status in Prostho- dontics in 1999 from the GDC. An ex-professional cricketer with Lan- cashire County Cricket Club, he is currently the President of the British Academy of Restorative Dentistry (www.bard.org.uk). He is one of the UK’s most successful dental teachers in the fields of Restorative, Cosmetic and Implant Dentistry over the last 20 years with more than 2000 den- tists completing a yearlong certifi- cate courses from one of the Tipton Training Academies (www.tipton- training.co.uk). Introduction Changes in vertical dimension are often required for either gaining re- storative space during restorative procedures or for improving facial aesthetics. Occlusal splints are used tofirstverifythattheincreaseinver- tical dimension can be tolerated and this is easily accomplished in most cases as long as this increase is done around RAP or Centre Relation so thatthecondylesareintheirmostre- laxed, bone braced and reproducible position. Increases and decreases in vertical dimension will be discussed showing positive changes in facial aestheticsastreatmentiscompleted. IncreasingVDO There is some debate among profes- sionals as to what constitutes the need to open VDO (vertical dimen- sion of occlusion) in the restora- tion of anterior teeth or partial or full mouth reconstruction. In most cases, clinicians look to alter verti- cal dimension for one or all of the following reasons: to gain space for the restoration of the teeth; to im- prove aesthetics; to correct occlusal relationships. Understanding what determines the VDO and what the effectsofalteringit haveonthetem- poromandibular joint (TMJ), muscle comfort, bite force, speech, and long- term occlusal stability are prerequi- sites to restoring the worn dentition. Spear clearly outlines the principles of VDO and concludes that “patients can function at many acceptable vertical dimensions, provided the condyles are functioning from cen- tric relation and the joint complex is healthy.” He states that “vertical is a highly adaptable position, and there is no single correct vertical di- mension.” Hefurtherconcludesthat the best vertical dimension is the one that satisfies the patient’s aes- thetic desires and the practitioner’s functional goals with the most con- servative approach. Article no. 3 in the series dealt with the diagnostic approach to increasing VDO. Mohin- dra showed that increasing UDO re- sultedinayoungerlookingpatient. Space When starting from retruded axis position, opening of the anterior teeth by 3 mm will yield a posterior separation of approximately 1 mm and stretch the masseter muscle length approximately 1 mm. If the condyles are not in retruded axis po- sitions and are subsequently seated to a more superior position, every millimeter of vertical seating will re- duce the masseter muscle length by 1 mm, thereby eliminating the need for a true opening of vertical dimen- sion. CaseStudy1 Mrs S (Fig 1) was referred to me by her General Dental Practitioner for a full mouth reconstruction because of the poor aesthetics of her upper crowns (Fig 2) and the wear taking place on her lower anterior teeth (Fig 3) and because she wanted an im- provementofhersmile(Fig4). As part of the initial diagnostics, an assessment was made of her vertical facial height by using an intra-oral face and wax jaw registration as de- scribed in article no. 3 (Figs 5 and 6) followed by a diagnostic wax-up at the increased vertical dimension (Figs7and8). Her anterior teeth showed severe wear in the lower and poor width/ length ratio of her upper crowns (Fig 9) together with a centre line shift of approximately2mm. Crownlength- ening procedures were done (Fig 10) followed by tooth preparations (Figs 11-14)andplacementofprototypesin sectionsasperthepreviousarticle. The stages in full mouth reconstruc- tion were followed as in article no. 4 of the series and the final end result can be seen in Figs 15-19, showing a facial improvement, and a younger lookingpatient. ReductionofVDO Conversely, although not as pre- dictable a procedure, reduction or shortening of vertical dimension is both possible and often advisable. It cases where there may be an overall anterior open bite, a simple poste- rior occlusal adjustment (reduction in vertical dimension) will result in anterior teeth meeting with the con- dyles in retruded axis position. This then allows for the development of a mutually protected occlusion and anterior guidance on the anterior teeth. The following case study will show how occlusal adjustment can improvepatientcomfort. A reduction in vertical dimension can also have a positive effect in facial aesthetics in taking a long, thin face and making it look more in proportion. However, a word of warning. Whilst increases in verti- cal dimension can be first tried out without any tooth destruction with anocclusalsplint,areductioncannot be tried out prior to tooth prepara- tion and so is not reversible. A great deal of experience is required before takingonacasesuchasthis. CaseStudy2 This lady was referred to me because of her failing upper anterior com- posite veneers, TMJ dysfunction and pooraesthetics(Fig20). Initialexam- ination revealed a near edge-to-edge occlusion (Fig 21) with a vertical and horizontal slide from RCP into ICP. UponmanipulationtoRCPtherewas an anterior open bite present. The goal of treatment was to equilibrate the patient and at the same time reduce her VDO so that better ante- riorcontactsweregainedandthento restore to a new ICP around her RAP withbetteranteriorguidance. Initialcastsweretakenandplacedon the semi-adjustable articulator (Fig 22). These casts had been pin-dexed sothattheposteriorquadrantscould be removed (Fig 23). Once reviewed the VDO was reduced by approxi- mately 3 mm showing true anterior contactsafteraplannedposterioroc- clusal equilibration (Fig 24). Further adjustment was then done on the casts so that the anterior teeth con- tacted in a more even manner (Figs 25-27), further reducing VDO by 2 mm(Figs28-30). Full diagnostic procedures were then performed including diagnos- tic wax-ups to this new reduced VDO (Figs 31, 32) and the patient was prepped for upper dentine bonded crowns (Fig 33) and upper and lower posterior porcelain fused to metal crowns. Note the patient’s lower anterior teeth were not restored but only whitened. Silver dies (Fig 34) were used by the technician for fab- rication of the final dentine bonded ÿPage 19